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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM 10-Q

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(Mark One)

​

☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

​

For the quarterly period ended June 30, 2025

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OR

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☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

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For the transition period from to

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Commission File Number: 001-37467

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Astria Therapeutics, Inc.

(Exact Name of Registrant as Specified in Its Charter)

​

Delaware |  | 26-3687168
(State or Other Jurisdiction of Incorporation or Organization) | ​ | (IRS Employer Identification No.)

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22 Boston Wharf Road 10th Floor |  | ​
Boston, Massachusetts | ​ | 02210
(Address of Principal Executive Offices) | ​ | (Zip Code)

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(617) 349-1971

(Registrant’s Telephone Number, Including Area Code)

​

Securities Registered pursuant to Section 12(b) of the Act:

Title of each class |  | Trading Symbol(s) |  | Name of each exchange on which registered
Common Stock, $0.001 par value per share | ​ | ATXS | ​ | The Nasdaq Stock Market LLC

​

Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act:

Large accelerated filer | ☐ | ​ | Accelerated filer | ☐
Non-accelerated filer | ☒ | ​ | Smaller reporting company | ☒
​ | ​ | ​ | Emerging growth company | ☐

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If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

As of July 31, 2025, there were 56,434,894 shares of the registrant’s common stock, par value $0.001 per share, outstanding.

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Table of Contents

TABLE OF CONTENTS

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|  |  | Page
PART I. FINANCIAL INFORMATION | ​ | 5
Item 1. | Financial Statements (unaudited) | ​ | 5
| Condensed Consolidated Balance Sheets as of June 30, 2025 and December 31, 2024 | ​ | 5
| Condensed Consolidated Statements of Operations for the three and six months ended June 30, 2025 and 2024 | ​ | 6
​ | Condensed Consolidated Statements of Comprehensive Loss for the three and six months ended June 30, 2025 and 2024 | ​ | 7
| Condensed Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders’ Equity for the three months ended March 31, 2025 and 2024 and the three months ended June 30, 2025 and 2024 | ​ | 8
| Condensed Consolidated Statements of Cash Flows for the six months ended June 30, 2025 and 2024 | ​ | 10
| Notes to Condensed Consolidated Financial Statements | ​ | 11
Item 2. | Management’s Discussion and Analysis of Financial Condition and Results of Operations | ​ | 21
Item 4. | Controls and Procedures | ​ | 31
PART II. OTHER INFORMATION | ​ | 33
Item 1A. | Risk Factors | ​ | 33
Item 5. | Other Information | ​ | 36
Item 6. | Exhibits | ​ | 37
​ | ​ | ​
SIGNATURES | ​ | 38

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS AND INDUSTRY DATA

This Quarterly Report on Form 10-Q contains forward-looking statements, which reflect our current views with respect to, among other things, our operations and financial performance, strategy, future financial condition and clinical and preclinical development programs. Such forward-looking statements are subject to various risks and uncertainties. Accordingly, there are or will be important factors that could cause actual outcomes or results to differ materially from those indicated in these statements. All statements, other than statements of historical facts, contained in this Quarterly Report on Form 10-Q, including statements regarding our strategy, future operations, future financial position, future revenues, projected costs, prospects, plans and objectives of management, clinical and preclinical development programs, regulatory filings and expected market growth are forward-looking statements. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words.

These forward-looking statements include, among other things, statements about:

| ● | our expectations regarding the potential significance of the results from the Phase 1a clinical trial, ALPHA-STAR Phase 1b/2 clinical trial and ALPHA–SOLAR trial of navenibart;

| ● | our expectations regarding the timing, nature, goals and results of the ALPHA-ORBIT Phase 3 clinical trial of navenibart, including the expected timing of release of topline results from such trial, and that favorable results from such trial and the ORBIT-EXPANSE long-term trial could support registration of navenibart as a potential treatment for hereditary angioedema, or HAE;

| ● | our expectations regarding development and clinical testing of any drug device combination for dosing of navenibart;

| ● | our expectations about the unmet medical need for HAE, the potential differentiating attributes of navenibart as a potential treatment for HAE, along with the potential market impact of such differentiation, the potential of navenibart to be a best-in-class, market-leading and patient-friendly treatment for HAE, and our vision for navenibart to become the first-choice preventative treatment for HAE with administration every three or six months with the goal of normalizing the lives of people living with HAE;

| ● | the HAE treatment landscape, the product profile of existing HAE therapies and HAE therapies under development, and the estimated size and anticipated growth of the global HAE market;

| ● | our expectations to continue to use third-party contract manufacturers to meet our nonclinical, clinical and commercial needs for navenibart, STAR-0310, and any other development candidate and statements regarding having adequate clinical and commercial supply of navenibart, any drug device combination of navenibart and STAR-0310;

| ● | the potential therapeutic benefits and potential attributes of STAR-0310 and our plans to develop STAR-0310 as a treatment for atopic dermatitis, or AD;

| ● | our expectations about the anticipated timing of early proof-of-concept data from the Phase 1a clinical trial of STAR-0310;

| ● | our expectations about the plans and potential design of a STAR-0310 proof-of-concept trial in AD patients;

| ● | the potential commercial opportunity for STAR-0310 in AD and the likelihood that it can effectively compete in AD, assuming it is approved;

| ● | the estimated size and anticipated growth of the AD market and the need for treatments for AD;

| ● | the potential to pursue the development of STAR-0310 in additional indications;

| ● | our goals and visions for the STAR-0310 program;

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| ● | our expectations regarding our ability to expand our pipeline;

| ● | our plans for and the potential costs, benefits and outcomes of our existing license agreement with Kaken Pharmaceutical Co., Ltd., and the potential benefits of any future acquisition, in-license, collaboration or preclinical development activities;

| ● | our manufacturing plans, capabilities and strategy;

| ● | our intellectual property position and strategy;

| ● | our facilities plans and capacity;

| ● | our management and mitigation of cybersecurity risks;

| ● | our estimates regarding our cash runway, expenses, future revenue, capital requirements and needs for additional financing, including additional financing to fund our long-term operations;

| ● | developments relating to our competitors and our industry; and

| ● | the impact of government laws and regulations.

We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements, and you should not place undue reliance on our forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements we make. We have included important factors in the cautionary statements included in the “Risk Factors” section of our Annual Report on Form 10-K for the fiscal year ended December 31, 2024 and any subsequent Quarterly Reports on Form 10-Q, particularly in the sections entitled “Summary of the Material Risks Associated with Our Business” and “Risk Factors” therein, that could cause actual results or events to differ materially from the forward-looking statements that we make. Our forward-looking statements do not reflect the potential impact of any future acquisitions, mergers, dispositions, collaborations, joint ventures or investments that we may make or enter into.

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PART I – FINANCIAL INFORMATION

Item 1. Financial Statements

Astria Therapeutics, Inc.

Condensed Consolidated Balance Sheets

(In thousands, except share and per share data)

(Unaudited)

​

​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | June 30, | ​ | December 31,
​ |  | 2025 |  | 2024
Assets | ​ | ​ | ​ | ​ | ​ | ​
Current assets: | ​ | ​ | ​ | ​ | ​ | ​
Cash and cash equivalents | ​ | $ | 76,319 | ​ | $ | 59,820
Short-term investments | ​ | ​ | 182,859 | ​ | ​ | 268,312
Prepaid expenses and other current assets | ​ |  | 9,408 | ​ |  | 6,511
Total current assets | ​ |  | 268,586 | ​ |  | 334,643
Right-of-use asset | ​ | ​ | 4,546 | ​ | ​ | 5,114
Other assets | ​ | ​ | 8,792 | ​ | ​ | 2,606
Total assets | ​ | $ | 281,924 | ​ | $ | 342,363
Liabilities and stockholders’ equity | ​ | ​ | ​ | ​ | ​ | ​
Current liabilities: | ​ | ​ | ​ | ​ | ​ | ​
Accounts payable | ​ | $ | 738 | ​ | $ | 4,320
Accrued expenses | ​ |  | 15,907 | ​ |  | 13,427
Current portion of operating lease liabilities | ​ | ​ | 1,399 | ​ | ​ | 1,384
Total current liabilities | ​ |  | 18,044 | ​ |  | 19,131
Long-term portion of operating lease liabilities | ​ | ​ | 3,367 | ​ | ​ | 3,969
Total liabilities | ​ | ​ | 21,411 | ​ | ​ | 23,100
Commitments (Note 7) | ​ | ​ | ​ | ​ | ​ | ​
Stockholders’ equity: | ​ | ​ | ​ | ​ | ​ | ​
Preferred stock, $0.001 par value per share, 4,908,620 shares authorized and no shares issued or outstanding | ​ | ​ | — | ​ | ​ | —
Series X redeemable convertible preferred stock, $0.001 par value per share, 91,380 shares authorized; 31,107 shares issued and outstanding as of June 30, 2025 and December 31, 2024, respectively | ​ | ​ | 95,324 | ​ | ​ | 95,324
Common stock, $0.001 par value per share, 150,000,000 shares authorized; 56,434,219 shares issued and outstanding at June 30, 2025 and December 31, 2024, respectively | ​ |  | 57 | ​ |  | 57
Additional paid-in capital | ​ |  | 906,703 | ​ |  | 898,513
Accumulated other comprehensive (loss) gain | ​ | ​ | (16) | ​ | ​ | 163
Accumulated deficit | ​ | ​ | (741,555) | ​ | ​ | (674,794)
Total stockholders’ equity | ​ |  | 260,513 | ​ |  | 319,263
Total liabilities and stockholders’ equity | ​ | $ | 281,924 | ​ | $ | 342,363

​

The accompanying notes are an integral part of these condensed consolidated financial statements.

​

​

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Astria Therapeutics, Inc.

Condensed Consolidated Statements of Operations

(In thousands, except share and per share data)

(Unaudited)

​

​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Three Months Ended June 30, | ​ | Six Months Ended June 30,
​ |  | 2025 |  | 2024 |  | 2025 |  | 2024
Operating expenses: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Research and development | ​ | $ | 25,945 | ​ | $ | 20,709 | ​ | $ | 53,731 | ​ | $ | 36,435
General and administrative | ​ |  | 9,875 | ​ |  | 8,094 | ​ |  | 19,084 | ​ |  | 16,518
Total operating expenses | ​ |  | 35,820 | ​ |  | 28,803 | ​ |  | 72,815 | ​ |  | 52,953
Loss from operations | ​ |  | (35,820) | ​ |  | (28,803) | ​ |  | (72,815) | ​ |  | (52,953)
Other income (expense): | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Interest and investment income | ​ | ​ | 2,889 | ​ | ​ | 4,647 | ​ | ​ | 6,235 | ​ | ​ | 8,888
Other expense, net | ​ | ​ | (121) | ​ | ​ | (16) | ​ | ​ | (181) | ​ | ​ | (35)
Total other income, net | ​ |  | 2,768 | ​ |  | 4,631 | ​ |  | 6,054 | ​ |  | 8,853
Net loss | ​ | ​ | (33,052) | ​ | ​ | (24,172) | ​ | ​ | (66,761) | ​ | ​ | (44,100)
Net loss per share attributable to common shareholders - basic and diluted | ​ | $ | (0.57) | ​ | $ | (0.43) | ​ | $ | (1.15) | ​ | $ | (0.81)
Weighted-average common shares outstanding used in net loss per share - basic and diluted | ​ |  | 58,005,312 | ​ |  | 56,485,962 | ​ |  | 58,005,312 | ​ |  | 54,390,364

​

The accompanying notes are an integral part of these condensed consolidated financial statements.

​

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Astria Therapeutics, Inc.

Condensed Consolidated Statements of Comprehensive Loss

(In thousands)

(Unaudited)

​

​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Three Months Ended June 30, |  | Six Months Ended June 30,
​ |  | 2025 |  | 2024 |  | 2025 |  | 2024
Net loss | ​ | $ | (33,052) | ​ | $ | (24,172) | ​ | $ | (66,761) | ​ | $ | (44,100)
Other comprehensive loss: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Unrealized loss on short-term investments, net of tax of $0 | ​ |  | (76) | ​ |  | (31) | ​ |  | (179) | ​ |  | (45)
Total other comprehensive loss: | ​ |  | (76) | ​ |  | (31) | ​ |  | (179) | ​ |  | (45)
Comprehensive loss | ​ | $ | (33,128) | ​ | $ | (24,203) | ​ | $ | (66,940) | ​ | $ | (44,145)

​

The accompanying notes are an integral part of these condensed consolidated financial statements.

​

​

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Astria Therapeutics, Inc.

Condensed Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders’ Equity

(In thousands, except share data)

​

(Unaudited)

​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Series X | ​ | Series X | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | redeemable | ​ | redeemable | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | Accumulated | ​ | ​ | ​
​ | ​ | convertible | ​ | convertible | ​ | ​ | ​ | ​ | ​ | Additional | ​ | ​ | ​ | ​ | other | ​ | ​ | Total
​ | ​ | preferred stock, | ​ | preferred stock, | ​ | Common stock, | ​ | Common stock, | ​ | paid-in | ​ | Accumulated | ​ | comprehensive | ​ | ​ | stockholders’
​ |  | shares |  | value |  | shares |  | par value |  | capital |  | deficit |  | gain (loss) |  | ​ | equity
Balance at December 31, 2024 | ​ | 31,107 | ​ | $ | 95,324 | ​ | 56,434,219 | ​ | $ | 57 | ​ | $ | 898,513 | ​ | $ | (674,794) | ​ | $ | 163 | ​ | $ | 319,263
Stock-based compensation expense | ​ | — | ​ | ​ | — | ​ | — | ​ | ​ | — | ​ | ​ | 3,839 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 3,839
Unrealized loss on short-term investments | ​ | — | ​ | ​ | — | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | (103) | ​ | ​ | (103)
Net loss | ​ | — | ​ | ​ | — | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | (33,709) | ​ | ​ | — | ​ | ​ | (33,709)
Balance at March 31, 2025 | ​ | 31,107 | ​ | ​ | 95,324 | ​ | 56,434,219 | ​ | ​ | 57 | ​ | ​ | 902,352 | ​ | ​ | (708,503) | ​ | ​ | 60 | ​ | ​ | 289,290
Stock-based compensation expense | ​ | — | ​ | ​ | — | ​ | — | ​ | ​ | — | ​ | ​ | 4,351 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 4,351
Unrealized loss on short-term investments | ​ | — | ​ | ​ | — | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | (76) | ​ | ​ | (76)
Net loss | ​ | — | ​ | ​ | — | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | (33,052) | ​ | ​ | — | ​ | ​ | (33,052)
Balance at June 30, 2025 | ​ | 31,107 | ​ | $ | 95,324 | ​ | 56,434,219 | ​ | $ | 57 | ​ | $ | 906,703 | ​ | $ | (741,555) | ​ | $ | (16) | ​ | $ | 260,513

​

The accompanying notes are an integral part of these condensed consolidated financial statements.

​

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Astria Therapeutics, Inc.

Condensed Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders’ Equity

(In thousands, except share data)

​

(Unaudited)

​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Series X | ​ | Series X | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | redeemable | ​ | redeemable | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | Accumulated | ​ | ​ | ​
​ | ​ | convertible | ​ | convertible | ​ | ​ | ​ | ​ | ​ | Additional | ​ | ​ | ​ | ​ | other | ​ | ​ | Total
​ | ​ | preferred stock, | ​ | preferred stock, | ​ | Common stock, | ​ | Common stock, | ​ | paid-in | ​ | Accumulated | ​ | comprehensive | ​ | ​ | stockholders’
​ |  | shares |  | value |  | shares |  | par value |  | capital |  | deficit |  | loss |  | ​ | equity
Balance at December 31, 2023 | ​ | 31,107 | ​ | $ | 95,324 | ​ | 41,034,797 | ​ | $ | 41 | ​ | $ | 728,285 | ​ | $ | (580,534) | ​ | $ | — | ​ | $ | 243,116
Issuance of common stock pursuant to an underwriting agreement, net of underwriter’s discount and issuance costs | ​ | — | ​ | ​ | — | ​ | 10,340,000 | ​ | ​ | 10 | ​ | ​ | 117,162 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 117,172
Issuance of common stock for at-the-market offerings, net of issuance costs | ​ | — | ​ | ​ | — | ​ | 2,945,806 | ​ | ​ | 3 | ​ | ​ | 19,999 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 20,002
Issuance of common stock upon exercise of options and warrants | ​ | — | ​ | ​ | — | ​ | 582,458 | ​ | ​ | 1 | ​ | ​ | 4,632 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 4,633
Stock-based compensation expense | ​ | — | ​ | ​ | — | ​ | — | ​ | ​ | — | ​ | ​ | 2,754 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 2,754
Unrealized loss on short-term investments | ​ | — | ​ | ​ | — | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | (14) | ​ | ​ | (14)
Net loss | ​ | — | ​ | ​ | — | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | (19,928) | ​ | ​ | — | ​ | ​ | (19,928)
Balance at March 31, 2024 | ​ | 31,107 | ​ | ​ | 95,324 | ​ | 54,903,061 | ​ | ​ | 55 | ​ | ​ | 872,832 | ​ | ​ | (600,462) | ​ | ​ | (14) | ​ | ​ | 367,735
Issuance of common stock upon exercise of options | ​ | — | ​ | ​ | — | ​ | 17,602 | ​ | ​ | — | ​ | ​ | 94 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 94
Stock-based compensation expense | ​ | — | ​ | ​ | — | ​ | — | ​ | ​ | — | ​ | ​ | 3,451 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 3,451
Unrealized loss on short-term investments | ​ | — | ​ | ​ | — | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | (31) | ​ | ​ | (31)
Net loss | ​ | — | ​ | ​ | — | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | (24,172) | ​ | ​ | — | ​ | ​ | (24,172)
Balance at June 30, 2024 | ​ | 31,107 | ​ | $ | 95,324 | ​ | 54,920,663 | ​ | $ | 55 | ​ | $ | 876,377 | ​ | $ | (624,634) | ​ | $ | (45) | ​ | $ | 347,077

​

The accompanying notes are an integral part of these condensed consolidated financial statements.

​

​

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Astria Therapeutics, Inc.

Condensed Consolidated Statements of Cash Flows

(In thousands)

(Unaudited)

​

​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Six Months Ended June 30,
​ |  | 2025 |  | 2024
Operating activities | ​ | ​ | ​ | ​ | ​ | ​
Net loss | ​ | $ | (66,761) | ​ | $ | (44,100)
Reconciliation of net loss to net cash used in operating activities: | ​ | ​ | ​ | ​ | ​ | ​
Stock-based compensation expense | ​ | ​ | 8,190 | ​ | ​ | 6,205
Right-of-use asset - operating lease | ​ | ​ | 568 | ​ | ​ | 401
Amortization (accretion) of premium (discount) on investment securities | ​ | ​ | (1,891) | ​ | ​ | (2,507)
Other non-cash items | ​ | ​ | 88 | ​ | ​ | 31
Changes in assets and liabilities: | ​ | ​ | ​ | ​ | ​ | ​
Prepaid expenses and other assets | ​ |  | (8,581) | ​ |  | 476
Operating lease liabilities | ​ | ​ | (587) | ​ | ​ | (293)
Accounts payable | ​ |  | (3,582) | ​ |  | 828
Accrued expenses | ​ |  | 2,480 | ​ |  | 3,074
Net cash used in operating activities | ​ |  | (70,076) | ​ |  | (35,885)
Investing activities | ​ | ​ | ​ | ​ | ​ | ​
Purchases of short-term investments | ​ | ​ | (1,339,835) | ​ | ​ | (2,437,029)
Sales and maturities of short-term investments | ​ | ​ | 1,427,000 | ​ | ​ | 2,243,000
Purchases of property and equipment | ​ | ​ | (590) | ​ | ​ | (305)
Net cash provided by (used in) investing activities | ​ |  | 86,575 | ​ |  | (194,334)
Financing activities | ​ | ​ | ​ | ​ | ​ | ​
Proceeds from public offering, net of underwriting discounts and issuance costs | ​ | ​ | — | ​ | ​ | 117,172
Proceeds from at-the-market offering, net of issuance costs | ​ | ​ | — | ​ | ​ | 20,002
Proceeds from exercise of stock options and warrants | ​ | ​ | — | ​ | ​ | 4,727
Net cash provided by financing activities | ​ | ​ | — | ​ | ​ | 141,901
Net increase (decrease) in cash, cash equivalents and restricted cash | ​ | ​ | 16,499 | ​ | ​ | (88,318)
Cash, cash equivalents and restricted cash, beginning of period | ​ |  | 59,820 | ​ |  | 175,693
Cash, cash equivalents and restricted cash, end of period | ​ | $ | 76,319 | ​ | $ | 87,375
Supplemental disclosure of non-cash transactions: | ​ | ​ | ​ | ​ | ​ | ​
Operating lease right-of-use assets obtained in exchange for operating lease liabilities | ​ | $ | — | ​ | $ | 5,753
Purchases of property and equipment in accounts payable and accrued liabilities | ​ | $ | — | ​ | $ | 199

​

The accompanying notes are an integral part of these condensed consolidated financial statements.

​

​

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Astria Therapeutics, Inc.

Notes to Condensed Consolidated Financial Statements

(Unaudited)

1. | Nature of Business

The Company

Astria Therapeutics, Inc. (the “Company”), is a biopharmaceutical company focused on the discovery, development and commercialization of novel therapeutics for allergic and immunologic diseases. The Company’s lead product candidate is navenibart, a potential best-in-class monoclonal antibody inhibitor of plasma kallikrein in clinical development for the treatment of hereditary angioedema (“HAE”), a rare, debilitating and potentially life-threatening disease. The Company’s second product candidate is STAR-0310, a monoclonal antibody OX40 antagonist that is in clinical development for the treatment of atopic dermatitis (“AD”), an immune disorder associated with loss of skin barrier function and itching. The Company was incorporated in the State of Delaware on June 26, 2008.

Liquidity

In June 2021, the Company entered into an Open Market Sale AgreementSM with Jefferies LLC (“Jefferies”), pursuant to which the Company could issue and sell shares of common stock under an at-the-market offering program (the “2021 ATM Program”), which was completed in the first quarter of 2024. In March 2024, the Company entered into a new Open Market Sale AgreementSM with Jefferies, pursuant to which the Company is able to issue and sell up to $150.0 million of shares of common stock under an at-the-market offering program (the “2024 ATM Program” and collectively with the 2021 ATM Program, the “ATM Programs”). The Company pays Jefferies commissions of up to 3% of the gross proceeds from any common stock sold through the ATM Programs. There was no activity in the 2024 ATM Program during the six months ended June 30, 2025 and 2024. During the six months ended June 30, 2024, the Company sold an aggregate of 2,945,806 shares of common stock under the 2021 ATM Program for gross proceeds of $20.6 million and net proceeds of $20.0 million.

As of June 30, 2025, the Company had an accumulated deficit of $741.6 million and had available cash, cash equivalents and short-term investments of $259.2 million. The Company estimates its existing cash, cash equivalents, and short-term investments are sufficient to sustain operations for at least twelve months from the issuance of these unaudited condensed consolidated financial statements.

The Company has not generated any product revenues and has financed its operations primarily through public offerings and private placements of its equity securities. There can be no assurance that the Company will be able to obtain additional debt, equity, or other financing or generate product revenue or revenues from collaborative partners, on terms acceptable to the Company, on a timely basis or at all. The failure of the Company to obtain sufficient funds on acceptable terms when needed could have a material adverse effect on the Company’s business, results of operations, and financial condition.

The Company is subject to a number of risks similar to other life science companies, including, but not limited to, successful discovery and development of its drug candidates, raising additional capital, development by its competitors of new technological innovations, protection of proprietary technology and regulatory approval and market acceptance of the Company’s products. The Company has been primarily involved with research and development activities and has incurred operating losses and negative cash flows from operations since its inception. The Company anticipates that it will continue to incur significant operating losses for the next several years as it continues to develop its product candidates.

​

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2. | Summary of Significant Accounting Policies

Basis of Presentation and Principles of Consolidation

The Company’s significant accounting policies are described in Note 2, “Summary of Significant Accounting Policies” in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2024 (the “2024 Annual Report on Form 10-K”), and there were no changes to such policies during the three and six months ended June 30, 2025 that had a material impact on the Company’s results of operations or financial position.

The accompanying financial statements and the related disclosures are unaudited and have been prepared in accordance with United States generally accepted accounting principles (“U.S. GAAP”). Additionally, certain information and footnote disclosures normally included in the Company’s annual financial statements have been condensed or omitted from this report. Accordingly, these unaudited condensed consolidated financial statements should be read in conjunction with the financial statements as of and for the year ended December 31, 2024 and the notes thereto included in the 2024 Annual Report on Form 10-K.

The unaudited condensed consolidated financial statements have been prepared on the same basis as the audited financial statements. In the opinion of the Company’s management, the accompanying unaudited condensed consolidated financial statements contain all adjustments, including those adjustments that are of a normal and recurring nature, which are necessary to fairly present the Company’s results for the interim periods presented. The results for the three and six months ended June 30, 2025 are not necessarily indicative of the results for the year ending December 31, 2025 or for any future period.

The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries, Astria Securities Corporation and Quellis Biosciences, LLC, successor in interest to Quellis Biosciences, Inc. All intercompany balances and transactions have been eliminated in consolidation.

Use of Estimates

The preparation of the Company’s unaudited condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the unaudited condensed consolidated financial statements and accompanying notes. Estimates are periodically reviewed considering changes in circumstances, facts and historical experience. Actual results could differ from such estimates.

The Company utilizes certain estimates to record expenses relating to research and development contracts and the valuation of stock-based awards. The contract estimates, which are primarily related to the length of service of each contract and the amount of service provided as of each measurement date, are determined by the Company based on input from internal project management, as well as from service providers.

Net Loss Per Share

Basic net loss per share attributable to common stockholders is calculated by dividing net loss attributable to common stockholders by the weighted average shares outstanding during the period, without consideration for common stock equivalents. The Company has included pre-funded warrants to purchase 1,571,093 shares of common stock at an exercise price of $0.001 per share in its computation of weighted average shares outstanding during the period. Diluted net loss per share attributable to common stockholders is calculated by adjusting weighted average shares outstanding for the dilutive effect of common stock equivalents outstanding for the period, determined using the treasury-stock method. For purposes of the Company’s dilutive net loss per share attributable to common stockholders calculation, stock options and warrants to purchase the Company’s common stock were considered to be common stock equivalents but were excluded from the calculation of diluted net loss per share attributable to common stockholders, as their effect would be anti-dilutive; therefore, basic and diluted net loss per share attributable to common stockholders were the same for all periods presented.

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The following common stock equivalents, including Series X Preferred Stock shown as common stock equivalents, were excluded from the calculation of diluted net loss per share for the periods indicated because including them would have had an anti-dilutive effect:

​

​ | ​ | ​ | ​ | ​
​ | ​ | Three and Six Months Ended June 30,
​ |  | 2025 |  | 2024
Stock options | ​ | 11,225,811 | ​ | 6,234,537
Common stock warrants |  | 6,796,280 | ​ | 6,796,280
Series X Preferred Stock |  | 5,184,591 | ​ | 5,184,591
​ | ​ | 23,206,682 | ​ | 18,215,408

​

Segment Information

Operating segments are identified as components of an enterprise for which separate discrete financial information is available for evaluation by the chief operating decision maker (“CODM”) in making decisions on how to allocate resources and assess performance. The CODM is the Company’s Chief Executive Officer. The Company views its operations and manages its business in one operating segment, focused on the discovery, development and commercialization of novel therapeutics for allergic and immunologic diseases. The Company operates in one geographic segment. Segment information is further described in Note 11, “Segment Reporting”.

Cash, Cash Equivalents and Restricted Cash

Cash, cash equivalents and restricted cash presented in the accompanying condensed consolidated balance sheets and condensed consolidated statements of cash flows are reconciled as follows (in thousands):

​

​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | June 30,
​ |  | 2025 |  | 2024
Cash and cash equivalents | ​ | $ | 76,319 | ​ | $ | 87,212
Restricted cash | ​ | ​ | — | ​ | ​ | 163
Total | ​ | $ | 76,319 | ​ | $ | 87,375

​

Preferred Stock Discount

In February 2021, the Company issued Series X Preferred Stock in a private placement transaction. The Company determined this transaction resulted in the recognition of a beneficial conversion feature, which was valued based on the difference between the price of the shares of common stock on the date of commitment and the conversion price on the closing date, resulting in a total value of $19.6 million. Additionally, the Company incurred total issuance costs of $5.7 million related to the private placement. Both of these features were recorded as a discount on Series X Preferred Stock recognized at the close of the transaction. These features are analogous to preferred dividends and are recorded as a non-cash return to holders of Series X Preferred Stock through additional paid-in capital. The discount related to the beneficial conversion feature is recognized through the earliest possible date of conversion, which occurred upon the stockholder approval of the conversion in June 2021. The issuance costs are recognized as a dividend at the time of conversion to common shares. As of June 30, 2025, $24.4 million of the above amounts were accounted for as a non-cash dividend related to shares of Series X Preferred Stock, and $0.9 million remained to be recognized upon future conversion.

Recently Enacted Tax Legislation

The One Big Beautiful Bill Act (“OBBBA”) was enacted in the United States on July 4, 2025. The OBBBA legislation provides for the permanent extension of certain expiring provisions of the Tax Cuts and Jobs Act, revisions to the international tax framework and the of favorable tax treatment for certain business provisions. The legislation has multiple effective dates, with certain provisions effective in 2025 and others implemented in future periods. The Company is currently evaluating the legislation’s impact on its consolidated financial statements.

Recent Accounting Pronouncements - Adopted

From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (“FASB”) or other standard setting bodies and adopted by the Company as of the specified effective date.

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In December 2023, the FASB issued Accounting Standards Update 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures (“ASU 2023-09”). This guidance is intended to enhance the transparency and decision-usefulness of income tax disclosures. The amendments in ASU 2023-09 address investor requests for enhanced income tax information primarily through changes to disclosure regarding rate reconciliation and income taxes paid both in the United States and in foreign jurisdictions. ASU 2023-09 is effective for fiscal years beginning after December 15, 2024 on a prospective basis, with the option to apply the standard retrospectively. Early adoption is permitted. ASU 2023-09 applies to disclosure requirements only, and the Company will provide required annual disclosures as part of the Company’s Annual Report on Form 10-K for the fiscal year ending December 31, 2025. The Company is currently evaluating this guidance to determine the impact it may have on its consolidated financial statement disclosures.

Recent Accounting Pronouncements – Not Yet Adopted

In November 2024, the FASB issued Accounting Standards Update 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses (“ASU 2024-03”). The amendments in ASU 2024-03 require public entities to disclose in a tabular format, on an annual and interim basis, the amounts of inventory purchases, employee compensation, depreciation and intangible asset amortization included in each income statement line item that contains those expenses. In January 2025, the FASB issued Accounting Standards Update 2025-01, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40) (“ASU 2025-01”). ASU 2025-01 amends the effective date of ASU 2024-03 to clarify that all public business entities are required to adopt the guidance in annual reporting periods beginning after December 15, 2026, and interim periods within annual reporting periods beginning after December 15, 2027. Early adoption of ASU 2024-03 is permitted. The Company is currently evaluating this guidance to determine the impact it may have on its consolidated financial statement disclosures.

​

3.Fair Value Measurements

The carrying amounts reflected in the unaudited condensed consolidated balance sheets for cash, prepaid expenses and other current assets, accounts payable and accrued expenses approximate their fair values due to the short-term nature of these assets and liabilities. Items measured at fair value on a recurring basis include cash equivalents and short-term investments as of June 30, 2025 and December 31, 2024.

​

The following tables present information about the Company’s financial assets and liabilities that have been measured at fair value and indicate the fair value hierarchy of the valuation inputs utilized to determine such fair value (in thousands):

​

​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | As of June 30, 2025
​ | ​ | Quoted Prices | ​ | Significant | ​ | Significant | ​ | ​
​ | ​ | in Active | ​ | Observable | ​ | Unobservable | ​ | ​
​ | ​ | Markets | ​ | Inputs | ​ | Inputs | ​ | ​
​ |  | (Level 1) |  | (Level 2) |  | (Level 3) |  | Total
Assets: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Cash and cash equivalents: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Money market funds | ​ | $ | 35,772 | ​ | $ | — | ​ | $ | — | ​ | $ | 35,772
Reverse repurchase agreements | ​ | ​ | — | ​ | ​ | 8,000 | ​ | ​ | — | ​ | ​ | 8,000
Short-term investments: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Reverse repurchase agreements | ​ | ​ | — | ​ | ​ | 68,000 | ​ | ​ | — | ​ | ​ | 68,000
Treasury notes | ​ | ​ | 64,685 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 64,685
Treasury bills | ​ | ​ | 41,984 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 41,984
Corporate debt securities | ​ | ​ | 8,190 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 8,190
Total | ​ | $ | 150,631 | ​ | $ | 76,000 | ​ | $ | — | ​ | $ | 226,631

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​

​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | As of December 31, 2024
​ | ​ | Quoted Prices | ​ | Significant | ​ | Significant | ​ | ​
​ | ​ | in Active | ​ | Observable | ​ | Unobservable | ​ | ​
​ | ​ | Markets | ​ | Inputs | ​ | Inputs | ​ | ​
​ |  | (Level 1) |  | (Level 2) |  | (Level 3) |  | Total
Assets: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Cash and cash equivalents: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Money market funds | ​ | $ | 30,610 | ​ | $ | — | ​ | $ | — | ​ | $ | 30,610
Short-term investments: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Treasury notes | ​ | ​ | 129,197 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 129,197
Reverse repurchase agreements | ​ | ​ | — | ​ | ​ | 100,000 | ​ | ​ | — | ​ | ​ | 100,000
Treasury bills | ​ | ​ | 39,115 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 39,115
Total | ​ | $ | 198,922 | ​ | $ | 100,000 | ​ | $ | — | ​ | $ | 298,922

​

There were no changes to the valuation methods used or transfers between Level 1, Level 2, and Level 3 during the three and six months ended June 30, 2025 and 2024.

​

​

4.Short-Term Investments

The following tables summarize short-term investments (in thousands):

​

​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | ​ | ​ |  | Gross Unrealized |  | Gross Unrealized |  | ​ | ​
​ | ​ | Amortized Cost | ​ | Gains | ​ | Losses | ​ | Fair Value
June 30, 2025 | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Reverse repurchase agreements | ​ | $ | 68,000 | ​ | $ | — | ​ | $ | — | ​ | $ | 68,000
Treasury notes | ​ | ​ | 64,690 | ​ | ​ | 7 | ​ | ​ | (12) | ​ | ​ | 64,685
Treasury bills | ​ | ​ | 41,994 | ​ | ​ | 1 | ​ | ​ | (11) | ​ | ​ | 41,984
Corporate debt securities | ​ | ​ | 8,191 | ​ | ​ | — | ​ | ​ | (1) | ​ | ​ | 8,190
Total | ​ | $ | 182,875 | ​ | $ | 8 | ​ | $ | (24) | ​ | $ | 182,859

​

​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Gross Unrealized | ​ | Gross Unrealized | ​ | ​ | ​
​ |  | Amortized Cost |  | Gains |  | Losses |  | Fair Value
December 31, 2024 | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Treasury notes | ​ | $ | 129,064 | ​ | $ | 136 | ​ | $ | (3) | ​ | $ | 129,197
Reverse repurchase agreements | ​ | ​ | 100,000 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 100,000
Treasury bills | ​ | ​ | 39,085 | ​ | ​ | 31 | ​ | ​ | (1) | ​ | ​ | 39,115
Total | ​ | $ | 268,149 | ​ | $ | 167 | ​ | $ | (4) | ​ | $ | 268,312

​

The contractual maturities of all short-term investments held at June 30, 2025 and December 31, 2024 were one year or less. There were twenty-three short-term investments in an unrealized loss position with an aggregate value of $79.9 million as of June 30, 2025 and two short-term investments in an unrealized loss position at December 31, 2024 with an aggregate value of $9.8 million. There were no short-term investments in an other than temporary unrealized loss position as of June 30, 2025 and December 31, 2024.

The Company is required to determine whether a decline in the fair value below the amortized cost basis of short-term investments is due to credit-related factors. At each reporting date, the Company performs an evaluation of impairment to determine if any unrealized losses are the result of credit losses. Impairment is assessed at the individual security level. Factors considered in determining whether a loss resulted from a credit loss or other factors include the Company’s intent and ability to hold the investment until the recovery of its amortized cost basis, the extent to which the fair value is less than the amortized cost basis, the length of time and extent to which fair value has been less than the cost basis, the financial condition of the issuer, any historical failure of the issuer to make scheduled interest or principal payments, any changes to the rating of the security by a rating agency, any adverse legal or regulatory events affecting the issuer or issuer’s industry, and any significant deterioration in economic conditions.

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Unrealized losses on short-term investments presented in the previous table have not been recognized in the condensed consolidated statements of operations because the securities are high credit quality, investment grade securities that the Company does not intend to sell and will not be required to sell prior to their anticipated recovery, and the decline in fair value is attributable to factors other than credit losses. Based on its evaluation, the Company determined it does not have any credit losses related to its short-term investments as of June 30, 2025 and December 31, 2024.

Gross realized gains and losses on the sales of short-term investments are included in other income, net. Unrealized holding gains or losses for the period that have been included in accumulated other comprehensive income, as well as gains and losses reclassified out of accumulated other comprehensive income into other income, net, were not material to the Company’s condensed consolidated statements of operations. The cost of investments sold or the amount reclassified out of the accumulated other comprehensive income into other income, net is based on the specific identification method for purposes of recording realized gains and losses. All proceeds during the three and six months ended June 30, 2025 and 2024 related to maturities of underlying investments. The gains on proceeds from maturities of short-term investments were not material to the Company’s condensed consolidated statements of operations for the three and six months ended June 30, 2025 and 2024.

​

5.Accrued Expenses

Accrued expenses consisted of the following (in thousands):
​

​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | June 30, | ​ | December 31,
​ |  | 2025 |  | 2024
Accrued contracted costs | ​ | $ | 10,507 | ​ | $ | 6,187
Accrued compensation | ​ | ​ | 3,309 | ​ | ​ | 5,084
Accrued professional fees | ​ | ​ | 1,937 | ​ | ​ | 1,963
Accrued other | ​ | ​ | 154 | ​ | ​ | 193
Total | ​ | $ | 15,907 | ​ | $ | 13,427

​

6.Leases

In January 2024, the Company entered into a sublease agreement (the “Sublease”) with Duck Creek Technologies LLC to occupy 30,110 square feet of office space in Boston, Massachusetts to replace its existing office space. The Sublease commenced on June 1, 2024 and will end on November 30, 2028 (or on such earlier date as the term may cease or expire as set forth in the Sublease). The Company concluded that the Sublease was an operating lease and recognized a lease liability and right-of-use (“ROU”) asset of approximately $5.8 million at the inception of the Sublease. The lease liability represents the present value of the remaining lease payments, discounted using the Company’s estimated incremental borrowing rate of 7.49%. The ROU asset represents the lease liability adjusted for any prepaid and accrued rent payments. The Sublease is secured by a security deposit of $0.4 million. As of June 30, 2025, the remaining lease term of the Sublease was 3.4 years.

As of June 30, 2025, minimum lease payments under the Company’s operating leases are summarized as follows (in thousands):

​ | ​ | ​ | ​
Year Ending December 31, |  | Amount
2025 | ​ | ​ | 663
2026 | ​ | ​ | 1,608
2027 | ​ | ​ | 1,640
2028 | ​ | ​ | 1,531
Total lease payments | ​ | $ | 5,442
Less: imputed interest | ​ | ​ | (676)
Total operating lease liabilities | ​ | $ | 4,766

​

Rent expense was $0.4 million and $0.8 million for the three and six months ended June 30, 2025, respectively, and $0.3 million and $0.4 million for the three and six months ended June 30, 2024, respectively. Lease payments were $0.4 million and $0.8 million for the three and six months ended June 30, 2025, respectively, and $0.3 million and $0.4 million for the three and six months ended June 30, 2024, respectively.

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7.Commitments

License and Research Agreements

In October 2023, the Company entered into a license agreement (the “Ichnos License Agreement”) with Ichnos Sciences SA and Ichnos Sciences Inc. (collectively, “Ichnos”) pursuant to which Ichnos granted to the Company an exclusive (even as to Ichnos and its affiliates), worldwide, and sublicensable right and license to certain patent rights and related know-how to develop, manufacture, and commercialize Ichnos’ proprietary OX40 portfolio. The OX40 portfolio includes Ichnos’ proprietary OX40 antagonist monoclonal antibody, with the generic name telazorlimab as well as Ichnos’ proprietary affinity matured next generation OX40 antagonist monoclonal antibody referred to by the Company as STAR-0310 (collectively, the “Licensed Compounds”). The Company agreed to use commercially reasonable efforts to develop, obtain regulatory approval for, and commercialize at least one product that contains or comprises a Licensed Compound (a “Licensed Product”) in the United States, France, Germany, Italy, Spain, the United Kingdom and Japan.

Under the terms of the Ichnos License Agreement, the Company paid Ichnos a one-time upfront license fee of $15.0 million in October 2023. The Company is obligated to pay Ichnos up to $305.0 million in milestone payments, consisting of up to $20.0 million upon the achievement of certain development milestones, up to $70.0 million upon the achievement of certain regulatory milestones and up to $215.0 million upon the achievement of certain commercial milestones, in each case in up to three indications with respect to the first applicable Licensed Product to achieve such milestone events. The specified clinical milestones related to the Phase 1a clinical trial of STAR-0310 were met and the Company paid the related $2.0 million of milestone payments during the three months ended March 31, 2025. There were no milestones met under the Ichnos License Agreement during the three months ended June 30, 2025 or during the three and six months ended June 30, 2024. The Company is also obligated to pay Ichnos tiered royalties ranging from a mid-single-digit percentage to a low-double-digit percentage on aggregate annual net sales of all Licensed Products. The Company is obligated to pay royalties on a Licensed Product-by-Licensed Product and country-by-country basis until the latest of: (i) the expiration of the last valid claim covering the composition of matter of such Licensed Product in such country; (ii) the expiration of the last regulatory exclusivity with respect to such Licensed Product in such country; and (iii) twelve years following the first commercial sale of such Licensed Product in such country. The royalty rate is subject to reduction on a Licensed Product-by-Licensed Product and country-by-country basis under certain circumstances.

The Company is also party to a research services agreement covering navenibart under which the Company is obligated to pay up to $2.7 million upon the achievement of certain clinical milestones, up to $5.9 million upon the achievement of certain regulatory milestones and up to $7.0 million upon the achievement of certain commercial milestones. The specified clinical milestones related to the ALPHA-ORBIT Phase 3 clinical trial of navenibart were met during the three months ended March 31, 2025 and the Company paid the related $2.2 million of milestone payments in April 2025. There were no milestones met under the research services agreement during the three months ended June 30, 2025 or during the three and six months ended June 30, 2024.

​

8.Stockholders’ Equity

Preferred Stock

Under the Company’s restated certificate of incorporation, as amended, the Company has 5,000,000 shares of preferred stock authorized for issuance, with a $0.001 par value per share. Preferred stock may be issued from time to time in one or more series, each series to have such terms as stated or expressed in the resolutions providing for the issue of such series adopted by the board of directors of the Company. Preferred stock which may be redeemed, purchased or acquired by the Company may be reissued except as otherwise provided by law. As of June 30, 2025, the Company had 31,107 shares of Series X Preferred Stock outstanding. Each share of Series X Preferred Stock is convertible into 166.67 shares of common stock and therefore the number of shares of underlying common stock issuable upon conversion of the Series X Preferred Stock is 5,184,591.

Common Stock

As of June 30, 2025, the Company had 150,000,000 shares of common stock authorized for issuance, $0.001 par value per share, with 56,434,219 shares issued and outstanding. The voting, dividend and liquidation rights of holders of common stock are subject to and qualified by the rights, powers and preferences of the holders of any outstanding preferred stock.

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Outstanding Warrants

The following table presents information about warrants that were issued and outstanding at June 30, 2025:

​

​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Year Issued |  | Equity Instrument |  | Warrants Outstanding |  | Exercise Price |  | Date of Expiration
2023 (1) |  | Common Stock | ​ | 6,796,280 | ​ | $ | 8.03 |  | 10/16/2028
Total |  | ​ | ​ | 6,796,280 | ​ |  | ​ |  | ​
Weighted average exercise price | ​ | ​ | ​ | ​ | ​ | $ | 8.03 |  | ​
Weighted average life in years | ​ | ​ | ​ | ​ | ​ |  |  |  | 3.30

(1)1,571,093 pre-funded warrants were issued in 2023 with an exercise price of $0.001 per share and are exercisable until all pre-funded warrants are exercised in full. 1,571,093 pre-funded warrants were outstanding as of June 30, 2025 and are not included in the table above.

​

9.Reserved for Future Issuance

The Company has reserved for future issuance the following shares of common stock:

​

​ | ​ | ​ | ​ | ​
​ |  | June 30, | ​ | December 31,
​ |  | 2025 |  | 2024
Options outstanding to purchase common stock |  | 11,225,811 | ​ | 6,850,889
Reserved under the 2015 Second Amended and Restated Stock Incentive Plan and the 2022 Inducement Stock Incentive Plan |  | 9,973,775 | ​ | 8,849,170
Warrants for the purchase of common stock | ​ | 8,367,373 | ​ | 8,367,373
Series X Preferred Stock | ​ | 5,184,591 | ​ | 5,184,591
Reserved under the employee stock purchase plan |  | 55,216 | ​ | 49,139
Total |  | 34,806,766 | ​ | 29,301,162

​

​

10.Stock-Based Compensation

Stock Option Activity

A summary of the Company’s stock option activity and related information follows:

​

​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | ​ | Weighted | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | ​ | Average | ​ | ​ | ​
​ | ​ | ​ | ​ | Weighted- | ​ | Remaining | ​ | Aggregate
​ | ​ | ​ | ​ | Average | ​ | Contractual | ​ | Intrinsic Value
​ |  | Shares |  | Exercise Price |  | Term (years) |  | (in thousands)
Outstanding at December 31, 2024 |  | 6,850,889 | ​ | $ | 13.75 |  | 8.31 | ​ | $ | 2,946
Granted |  | 4,450,300 | ​ | $ | 6.53 | ​ | ​ | ​ | ​ | ​
Cancelled or forfeited |  | (74,905) | ​ | $ | 9.97 | ​ | ​ | ​ | ​ | ​
Expired | ​ | (473) | ​ | $ | 682.65 | ​ | ​ | ​ | ​ | ​
Outstanding at June 30, 2025 | ​ | 11,225,811 | ​ | $ | 10.89 | ​ | 8.56 | ​ | $ | 447
Vested and exercisable at June 30, 2025 | ​ | 3,570,804 | ​ | $ | 14.39 | ​ | 7.22 | ​ | $ | 302
Vested and expected to vest at June 30, 2025 |  | 11,225,811 | ​ | $ | 10.89 | ​ | 8.56 | ​ | $ | 447

​

There were no options exercised during the three and six months ended June 30, 2025. The intrinsic value of stock options exercised during the three and six months ended June 30, 2024 was $0.1 million and $0.2 million, respectively. The total grant date fair value of stock options vested for the three and six months ended June 30, 2025 was $3.9 million and $12.2 million, respectively. The total grant date fair value of stock options vested for the three and six months ended June 30, 2024 was $2.5 million and $5.6 million, respectively. The weighted-average grant date fair value per share of options granted for the three and six months ended June 30, 2025 was $3.75 and $4.56, respectively. The weighted-average grant date fair value per share of options granted for the three and six months ended June 30, 2024 was $6.64 and $9.95, respectively.

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As of June 30, 2025, the total unrecognized compensation expense related to unvested stock option awards was $44.8 million. The Company expects to recognize that cost over a weighted-average period of approximately 2.8 years.

Stock-Based Compensation Expense

During the three and six months ended June 30, 2025 and 2024, the Company recorded stock-based compensation expense for employee and non-employee stock options and restricted stock, which was allocated as follows in the statements of operations (in thousands):

​

​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Three Months Ended June 30, | ​ | Six Months Ended June 30,
​ |  | 2025 |  | 2024 |  | 2025 |  | 2024
General and administrative | ​ | $ | 2,729 | ​ | $ | 2,531 | ​ | $ | 5,266 | ​ | $ | 4,581
Research and development | ​ | ​ | 1,622 | ​ | ​ | 920 | ​ |  | 2,924 | ​ |  | 1,624
Total | ​ | $ | 4,351 | ​ | $ | 3,451 | ​ | $ | 8,190 | ​ | $ | 6,205

​

No related tax benefits were recognized during the three and six months ended June 30, 2025 and 2024.

​

11.Segment Reporting

The Company operates and manages its business as one reportable segment and one operating segment focused on the discovery, development and commercialization of novel therapeutics for allergic and immunologic diseases. The CODM assesses performance for the segment and decides how to allocate resources based on consolidated net loss, which is also reported on the condensed consolidated statements of operations and condensed consolidated statements of comprehensive loss.

The measure of segment assets reviewed by the CODM is consolidated total assets, which is reported on the condensed consolidated balance sheets. All material long-lived assets are located in the United States. Long-lived assets consist of property and equipment, net, and operating lease right-of-use assets.

The CODM uses consolidated net loss to evaluate the Company’s spend and to monitor budget versus actual results. The monitoring of budgeted versus actual results is used in assessing performance of the segment and in establishing resource allocation across the organization.

Factors used in determining the reportable segment include the nature of the Company’s operating activities, the organizational and reporting structure and the type of information reviewed by the CODM to allocate resources and evaluate financial performance. The accounting policies of the segment are the same as those described in Note 2, “Summary of Significant Accounting Policies”.

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The following table presents reportable segment profit and loss, including significant expense categories, attributable to the Company’s reportable segment for the periods presented:

​

​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Three Months Ended June 30, |  | Six Months Ended June 30,
​ |  | 2025 |  | 2024 |  | 2025 |  | 2024
Expenses(1): | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Research and development: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Navenibart | ​ | $ | 11,082 | ​ | $ | 7,935 | ​ | $ | 22,911 | ​ | $ | 15,071
STAR-0310 | ​ |  | 5,738 | ​ |  | 5,710 | ​ |  | 13,174 | ​ |  | 8,685
Employee expenses | ​ |  | 4,647 | ​ |  | 3,195 | ​ |  | 9,297 | ​ |  | 6,632
General and administrative: | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​
Program support(2) | ​ |  | 373 | ​ |  | 9 | ​ |  | 344 | ​ |  | 206
Employee expenses | ​ |  | 3,330 | ​ |  | 2,736 | ​ |  | 6,854 | ​ |  | 5,598
Stock-based compensation expense | ​ |  | 4,351 | ​ |  | 3,451 | ​ |  | 8,190 | ​ |  | 6,205
Consulting and professional services expenses | ​ |  | 4,274 | ​ |  | 4,459 | ​ |  | 8,278 | ​ |  | 7,828
Other segment expenses(3) | ​ |  | 2,025 | ​ |  | 1,308 | ​ |  | 3,767 | ​ |  | 2,728
Other income, net(4) | ​ |  | (2,768) | ​ |  | (4,631) | ​ |  | (6,054) | ​ |  | (8,853)
Segment net loss | ​ | $ | 33,052 | ​ | $ | 24,172 | ​ | $ | 66,761 | ​ | $ | 44,100

(1)The significant expense categories and amounts align with segment level information that is regularly provided to the CODM.
(2)General and administrative program support expense includes pre-commercial costs incurred in support of navenibart and STAR-0310, and patient advocacy costs incurred in support of navenibart and STAR-0310.
(3)Other segment expenses include: costs incurred in support of overall research and development activities and non-specific programs, facilities expense, office expense, insurance expense and depreciation and amortization.
(4)Other income, net, consists primarily of interest income on investments, as further described in Note 4, “Short-Term Investments”. For the three and six months ended June 30, 2025, the Company recognized interest income of $2.9 million and $6.2 million, respectively. For the three and six months ended June 30, 2024, the Company recognized interest income of $4.6 million and $8.9 million, respectively.

​

12.Subsequent Events

On August 6, 2025, the Company entered into a license agreement (the “Kaken License Agreement”) with Kaken Pharmaceutical, Co., Ltd. (“Kaken”), pursuant to which the Company granted an exclusive license under certain patent rights and know-how controlled by the Company for Kaken to develop, package, and commercialize navenibart, a long-acting investigational monoclonal antibody inhibitor of plasma kallikrein (the “Navenibart Licensed Product”), for the prevention of HAE attacks in humans (the “Field”), in Japan.

Under the terms of the Kaken License Agreement, the Company will receive an upfront payment of $16.0 million, with a potential for an additional $16.0 million in total commercialization and sales milestones. In addition to these payments, on a Navenibart Licensed Product-by-Navenibart Licensed Product basis, the Company is eligible for tiered royalties, with the royalty rate as a percentage of net sales from the mid-teens to 30%. Kaken’s royalty payment obligations commence on the first commercial sale of each Navenibart Licensed Product in Japan and continue until the latest of (i) the expiration of the last to expire valid claim of specified Company patents rights covering such Navenibart Licensed Product in Japan, (ii) the expiration of the last to expire regulatory exclusivity with respect to such Navenibart Licensed Product in Japan, and (iii) ten (10) years following the first commercial sale of such Navenibart Licensed Product in Japan (each such term with respect to a Navenibart Licensed Product, the “Royalty Term”). Pursuant to the terms of the Kaken License Agreement, Kaken will also provide support for the Company’s ALPHA-ORBIT Phase 3 trial in Japan, be responsible for regulatory submissions in Japan, and reimburse the Company for a portion of the costs of the navenibart Phase 3 program. Kaken is obligated to use commercially reasonable efforts to obtain regulatory approval and reimbursement approval for, and commercialize, at least one Navenibart Licensed Product in the Field in Japan.

Unless earlier terminated, the Kaken License Agreement will expire on the expiration of the last-to-expire Royalty Term. The Kaken License Agreement may be terminated by either party for the other party’s uncured material breach, insolvency or bankruptcy. Additionally, Kaken may terminate the Kaken License Agreement upon 30 days’ notice for a material safety issue, or at its convenience with 90 days’ notice.

​

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Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations

You should read the following discussion and analysis of our financial condition and results of operations together with our unaudited condensed consolidated financial statements and the related notes and other financial information included elsewhere in this Quarterly Report on Form 10-Q and the audited consolidated financial statements and notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2024, or the 2024 Annual Report on Form 10-K. Some of the information contained in this discussion and analysis or set forth elsewhere in this Quarterly Report on Form 10-Q, including information with respect to our plans and strategy for our business, includes forward-looking statements that involve risks and uncertainties. You should review the sections entitled “Risk Factors” and “Summary of the Material Risks Associated with Our Business” in the 2024 Annual Report on Form 10-K and any subsequent reports on Form 10-Q for a discussion of important factors that could cause actual results to differ materially from the results described in or implied by the forward-looking statements contained in the following discussion and analysis. This section provides additional information regarding our business, current developments, results of operations, cash flows, financial condition, contractual commitments and critical accounting policies and estimates that require significant judgement and have the most potential impact on our unaudited condensed consolidated financial statements. This discussion and analysis is intended to better allow investors to view our Company from management’s perspective.

Overview

We are a biopharmaceutical company focused on the discovery, development and commercialization of novel therapeutics for allergic and immunologic diseases. Our focus is to develop first-choice therapies that improve the health and outcomes of patients with allergic and immunologic diseases. Our lead product candidate is navenibart, a potential best-in-class monoclonal antibody inhibitor of plasma kallikrein in clinical development for the treatment of hereditary angioedema, or HAE, a rare, debilitating and potentially life-threatening disease. We believe that navenibart has the potential to be the market-leading and most patient-friendly chronic treatment option for HAE, based on proof-of-concept data in HAE patients and the existing HAE treatment landscape. Our second product candidate is STAR-0310, a monoclonal antibody OX40 antagonist that is in clinical development for the treatment of atopic dermatitis, or AD, an immune disorder associated with loss of skin barrier function and itching. We believe that with both of these programs, we are advancing a pipeline of products with meaningfully differentiated profiles based on validated mechanisms.

Navenibart

The treatment options for patients with HAE have improved in recent years, however, there is remaining unmet medical need and the global market for HAE therapy is strong and growing. The goal for navenibart is to develop a best-in-class monoclonal antibody inhibitor of plasma kallikrein able to provide long-acting, effective attack prevention for HAE. Our vision for navenibart is to lead the HAE market and become the first-choice preventative treatment for HAE with administration every three and six months with the goal of normalizing the lives of people living with HAE. Targeted plasma kallikrein inhibition can prevent HAE attacks by suppressing the pathway that generates bradykinin and causes excessive swelling. Navenibart is currently in clinical development and the U.S. Food and Drug Administration, or FDA, has granted Fast Track and Orphan Drug designations to navenibart for the treatment of HAE. The European Commission has granted Orphan Medicinal Product Designation to navenibart for the treatment of HAE.

In February 2025, we initiated a Phase 3 trial of navenibart called ALPHA-ORBIT. This global, randomized, double-blind, placebo-controlled trial is evaluating the efficacy and safety of navenibart over a 6-month treatment period in up to 135 adults and 10 adolescents (open-label), with Type 1 or Type 2 HAE. Adult patients will be randomized to receive one of three navenibart dose arms: 1) an initial 600 mg dose followed by 300 mg every 3 months (Q3M), 2) 600 mg every six months (Q6M), 3) 600 mg Q3M, or placebo; adolescents will receive an initial 600 mg dose followed by 300 mg Q3M. The dose arms support the potential to provide patient-centered dosing flexibility to people with HAE. The primary endpoint is time-normalized monthly HAE attacks at 6 months, and a key secondary endpoint includes the proportion of participants who are attack-free at 6 months. After 6 months, patients may be eligible to enter ORBIT-EXPANSE, a long-term trial, in which all patients will be treated with navenibart (open-label) and which will include a patient-centered flexible dosing period. The navenibart Phase 3 program will consist of the ALPHA-ORBIT Phase 3 trial and ORBIT-EXPANSE, which are designed to support registration globally. Top-line results from the ALPHA-ORBIT trial are anticipated in early 2027. In addition, to ease the administration of navenibart, we are developing both autoinjector and pre-filled syringe drug device combinations.

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In February 2023, we initiated a Phase 1b/2 trial of navenibart called ALPHA-STAR, or Astria Long-acting Prophylaxis for Hereditary Angioedema: STAR-0215. This global, multi-center, open-label, single and multiple dose proof-of-concept clinical trial in people with HAE evaluated safety, tolerability, HAE attack rate reduction, pharmacokinetics, or PK, pharmacodynamics, and quality of life in patients three and six months after subcutaneous navenibart administration. We reported initial proof-of-concept data in HAE patients in March 2024. Target enrollment of 16 patients was achieved with all doses administered, and we reported final results from ALPHA-STAR target enrollment in December 2024, which were as follows:

Cohort 1 evaluated a single 450 mg dose (n=4). The results for the cohort measured over 6 months were averages of:

| ● | a 91% reduction in monthly attack rate;

| ● | a 96% reduction in moderate and severe attacks; and

| ● | a 94% reduction in acute rescue medication use; with

| ● | 50% of patients being attack-free through 3 months of follow-up, and 25% being attack-free through 6 months of follow-up.

Cohort 2 evaluated a 600 mg dose followed by a 300 mg dose three months later, on Day 84 (n=6). The results for the cohort measured over 6 months were averages of:

| ● | a 95% reduction in monthly attack rate;

| ● | a 95% reduction in moderate and severe attacks; and

| ● | a 94% reduction in acute rescue medication use; with

| ● | 67% of patients being attack-free.

Cohort 3 received a 600 mg dose followed by a 600 mg dose one month later, on Day 28 (n=6). The results for the cohort measured over 6 months were averages of:

| ● | a 92% reduction in monthly attack rate;

| ● | a 96% reduction in moderate and severe attacks; and

| ● | a 91% reduction in acute rescue medication use; with

| ● | 67% of patients being attack-free.

Navenibart was generally well-tolerated with no serious treatment-emergent adverse events, or TEAEs, and no discontinuations. There were four non-severe and quickly resolved treatment-related TEAEs: one case of dizziness, one transient injection site reaction (rash), one case of injection site erythema and one case of injection site pruritus. There were no injection site reactions of pain.

Enrollment in ALPHA-STAR was expanded and a total of 29 patients were enrolled in the trial in order to accelerate the collection of data to support potential regulatory filings and future approvals.

ALPHA-SOLAR, a long-term open-label trial assessing the long-term safety and efficacy of navenibart, is ongoing. All of the 29 patients from ALPHA-STAR elected to enroll in ALPHA-SOLAR. Participants are being assigned to receive navenibart in one of two dosing regimens: either 300mg Q3M or 600mg Q6M. We reported positive initial safety and efficacy results from the 16 target enrollment patients from ALPHA-SOLAR at the European Academy of Allergy and Clinical Immunology (EAACI) conference in June 2025. The initial results demonstrated robust overall reduction in the monthly attack rate, further support navenibart’s favorable safety and tolerability profile, and potential Q3M and Q6M dosing regimens.

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Initial results from ALPHA-SOLAR:

​

​ |  |  |
​ | Mean/Median Reduction in Monthly Attack Rate | Mean/Median Reduction in Moderate and Severe Monthly Attack Rate | Mean/Median Reduction in Monthly Rate of Attacks Requiring Rescue Medication
Overall ​ (n=16, 10.1 mean/9.1 median months of follow-up) | 92%/97% | 95%/100% | 92%/98%
Arm A ​ 600 mg/300 mg Q3M ​ (n=10, 11.3 mean/9.3 median months of follow-up | 95%/99% | 96%/100% | 95%/98%
Arm B ​ 600 mg/600 mg at Day 28, 600 mg Q6M ​ (n=6, 8 mean/7.4 median months of follow up) | 86%/90% | 90%/94% | 87%/95%

​

All results presented in the table above are compared to baseline from ALPHA-STAR.

In the ALPHA-SOLAR trial, navenibart demonstrated overall attack-freedom of 50% over 6 months, which is the longest period of follow-up for all 16 patients to date. All 16 patients remain in the ALPHA-SOLAR trial. Navenibart was well-tolerated with no severe or serious treatment-emergent adverse events and no discontinuations. One participant experienced two treatment-related, mild injection site reactions that resolved without treatment. There were no injection site reactions of pain.

In both ALPHA-STAR and ALPHA-SOLAR, the safety profile of navenibart in patients with HAE was favorable through more than 17 months (mean/median) of cumulative follow-up since the initiation of navenibart in ALPHA-STAR.

On August 6, 2025, we entered into a license agreement (the “Kaken License Agreement”) with Kaken Pharmaceutical, Co., Ltd. (“Kaken”), pursuant to which we granted an exclusive license under certain patent rights and know-how controlled by us for Kaken to develop, package, and commercialize navenibart for the prevention of HAE attacks in humans in Japan. Under the terms of the Kaken License Agreement, we will receive an upfront payment of $16.0 million, with a potential for an additional $16.0 million in total commercialization and sales milestones. In addition to these payments, we are eligible for tiered royalties, with the royalty rate as a percentage of net sales from the mid-teens to 30%. Pursuant to the terms of the Kaken License Agreement, Kaken will also provide support for our ALPHA-ORBIT Phase 3 trial in Japan, be responsible for regulatory submissions in Japan, and reimburse us for a portion of the costs of the navenibart Phase 3 program.

STAR-0310

We believe that OX40 inhibition has the potential to treat AD and other diseases. The current treatment options in AD are insufficient to address the needs of many patients, and standard of care treatments include steroids and topical medications which can treat symptoms but do not address the underlying disease. Our goal for STAR-0310 is to reduce disease activity, relapse rate, and treatment burden for patients with moderate-to-severe AD. STAR-0310 was engineered with YTE half-life extension technology to enable infrequent dosing. As a potential long-acting OX40 inhibitor, STAR-0310 aims to address the need for a safe, effective, and infrequently administered AD treatment.

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In January 2025, we announced the initiation of our Phase 1a trial of STAR-0310 in healthy subjects. The Phase 1a randomized, double-blind, placebo-controlled single ascending dose trial is evaluating the safety, tolerability, PK, and immunogenicity of STAR-0310 in approximately 40 healthy adult participants. We anticipate early proof-of-concept results from the trial in the third quarter of 2025.

In June 2025 we shared data on STAR-0310’s differentiated profile at the EAACI conference, which support STAR-0310 as a potential best-in-class OX40 antagonist, with a unique allosteric inhibition mechanism, enhanced disruption of OX40/OX40L signaling compared to other agents, and pure antagonistic activity without agonism. These findings, along with previously reported low antibody-dependent cellular cytotoxicity activity and robust cytokine suppression, highlight STAR-0310’s differentiated profile and its potential to achieve deeper inhibition of T cell responses.

Based on results from the Phase 1a clinical trial, we will determine next steps for the STAR-0310 program, which could include a proof-of-concept clinical trial of STAR-0310 in patients with AD. The goals of the proof-of-concept trial would be to demonstrate initial efficacy in AD as well as show differentiation in safety and tolerability and the potential for a reduced treatment burden as a result of extended half-life as compared to existing therapies.

Financial Overview

Our business is almost entirely dependent on the success of navenibart and STAR-0310. Navenibart is in clinical development and has only produced results in Phase 1a and Phase 1b/2 clinical testing and in preclinical and nonclinical settings. STAR-0310 entered into early clinical development in January 2025. Our net losses were $66.8 million and $44.1 million for the six months ended June 30, 2025 and 2024, respectively. As of June 30, 2025, we had an accumulated deficit of $741.6 million. We have not generated any product revenues and have financed our operations primarily through public offerings and private placements of our equity securities and have devoted substantially all of our financial resources and efforts to research and development, including preclinical studies and clinical development programs.

As of June 30, 2025, we had $259.2 million in cash, cash equivalents and short-term investments, which, together with the Kaken upfront payment and expected reimbursement of a portion of our Phase 3 program costs, we expect will enable us to fund our operating expenses and capital expenditure requirements into 2028. Our current operating plan includes (i) for navenibart, support for all program activities through completion of our ALPHA-ORBIT Phase 3 trial, including activities related to the planned ORBIT-EXPANSE long-term trial and Phase 3 development and testing of drug device combinations, and (ii) for STAR-0310, the completion of the ongoing Phase 1a clinical trial of healthy subjects. We have based this estimate on assumptions that may prove to be wrong, and we could use our available capital resources sooner than we currently expect. Advancing the development and commercialization of navenibart, any drug device combination for navenibart, STAR-0310 or any future product candidates will require a significant amount of capital, and our existing cash, cash equivalents and short-term investments, including the Kaken upfront payment and the expected reimbursement by Kaken of a portion of our Phase 3 program costs, will not be sufficient to enable us to fund the completion of development of any of our product candidates, including navenibart, any drug device combination for navenibart, STAR-0310 or any future product candidate. We will need to obtain substantial additional funding to complete the development and commercialization of navenibart, any drug device combination for navenibart, STAR-0310 or any future product candidates and support our continuing operations, future clinical trials and expansion of our pipeline. Furthermore, our operating plan may change as a result of many factors currently unknown to us, and we may need to seek additional financing to fund our long-term operations sooner than planned. See the section titled “Liquidity and Capital Resources” below for additional information.

Revenue

As of June 30, 2025, we have not generated any revenue from product sales.

Research and Development Expenses

Research and development expenses consist primarily of costs incurred for our research activities, including our drug discovery efforts, and the development of our product candidates and drug device combination candidates, which include:

| ● | employee-related expenses, including salaries, benefits and stock-based compensation expense;

| ● | expenses incurred under agreements with third parties, including contract research organizations, or CROs, that conduct clinical trials and research and development and preclinical activities on our behalf;

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| ● | the cost of consultants;

| ● | the cost of lab supplies and acquiring, developing and manufacturing study and clinical trial materials; and

| ● | facilities and other expenses, which include direct and allocated expenses for rent and maintenance of facilities, insurance and other supplies.

Research and development costs are expensed as incurred. Nonrefundable advance payments for goods or services to be received in the future for use in research and development activities are deferred and capitalized. The capitalized amounts are expensed as the related goods are delivered or the services are performed.

We typically use our employee, consultant and infrastructure resources across our development programs. We track outsourced development costs by product candidate or development program, but we do not allocate personnel costs, other internal costs or external consultant costs to specific product candidates or development programs. We record our research and development expenses net of any research and development tax incentives we are entitled to receive from government authorities.

The following table summarizes our research and development expenses by program (in thousands):

​

​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Six Months Ended June 30,
​ |  | 2025 |  | 2024
Navenibart | ​ | $ | 22,911 | ​ | $ | 15,071
STAR-0310 | ​ | ​ | 13,174 | ​ | ​ | 8,685
Other programs | ​ | ​ | 854 | ​ | ​ | 497
Costs not directly allocated to programs: | ​ |  | ​ | ​ |  | ​
Employee expenses including cash compensation, benefits and stock-based compensation | ​ |  | 12,221 | ​ |  | 8,256
Consultants and professional expenses | ​ |  | 3,777 | ​ |  | 3,201
Facilities | ​ | ​ | 446 | ​ | ​ | 288
Other | ​ |  | 348 | ​ |  | 437
Total costs not directly allocated to programs | ​ |  | 16,792 | ​ |  | 12,182
Total research and development expenses | ​ | $ | 53,731 | ​ | $ | 36,435

​

We expect to incur significant research and development expenses in the year ending December 31, 2025, and in future periods in connection with the clinical trials and other activities related to the development of navenibart and one or more drug device combinations for navenibart, in addition to expenses related to clinical trials and other activities related to the development of STAR-0310. Because of this, we expect that our research and development expenses over the next several quarters will be higher than the prior year periods. Development of navenibart, drug device combinations for navenibart, STAR-0310 and any future product candidates is highly uncertain, and we cannot reasonably estimate at this time the nature, timing and costs of the efforts that would be necessary to complete the development of any such product candidates. We are also unable to predict when, if ever, material net cash inflows would commence from navenibart, STAR-0310 or any other future product candidates. This is due to the fact that we would need to raise substantial additional capital to fund the completion of the clinical development of any such product candidates and the numerous risks and uncertainties associated with developing and commercializing product candidates, including the uncertainties of:

| ● | establishing an appropriate safety profile with Investigational New Drug Application enabling toxicology studies;

| ● | successful design of, enrollment in, and completion of clinical trials;

| ● | feedback from the FDA and foreign regulatory authorities on planned trial designs, preclinical studies and manufacturing capabilities and plans;

| ● | changes in the FDA and foreign regulatory approval processes or perspectives that may delay or prevent the approval of new products;

| ● | receipt of marketing approvals from applicable regulatory authorities;

| ● | establishing commercial manufacturing capabilities or making arrangements with third-party manufacturers;

| ● | obtaining and maintaining patent and trade secret protection and regulatory exclusivity;

| ● | launching commercial sales, if we are able to obtain marketing approval, whether alone or in collaboration with others, and our ability to compete successfully with other products; and

| ● | maintaining a continued acceptable safety profile following approval.

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A change in the outcome of any of these variables with respect to the development of navenibart, any drug device combination for navenibart, STAR-0310 or any future product candidate would significantly change the costs and timing associated with the development of that product candidate.

For additional information, see the section titled “Research and Development Expenses” under the heading “Results of Operations” below.

General and Administrative Expenses

General and administrative expenses consist primarily of salaries and other related costs, including stock-based compensation, for personnel in executive, finance, accounting, information technology, new product planning, business development, legal and human resources functions. Other significant costs include facility costs not otherwise included in research and development expenses, legal fees relating to patent and corporate matters, and fees for accounting and consulting services.

We anticipate that our general and administrative expenses will increase from their current levels as we continue to grow our company, develop navenibart, drug device combination for navenibart and STAR-0310, and potentially expand our pipeline to include other product candidates.

Other Income (Expense)

Other income (expense) consists of interest and investment income earned on our cash, cash equivalents and short-term investments, net of accretion income and amortization expense on short-term investments, and gains and losses related to foreign currency fluctuations.

Critical Accounting Estimates

This discussion and analysis of our financial condition and results of operations is based on our financial statements, which we have prepared in accordance with United States generally accepted accounting principles. We believe that several accounting policies are important to understanding our historical and future performance. We refer to these policies as critical because these specific areas generally require us to make judgments and estimates about matters that are uncertain at the time we make the estimate, and different estimates—which also would have been reasonable—could have been used. On an ongoing basis, we evaluate our estimates and judgments. We base our estimates on historical experience and other market-specific or other relevant assumptions that we believe to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions.

During the six months ended June 30, 2025, there were no material changes to our critical accounting policies as reported in our 2024 Annual Report on Form 10-K.

Results of Operations

Comparison of the Three Months Ended June 30, 2025 and 2024

The following table summarizes our results of operations for the three months ended June 30, 2025 and 2024, together with the period-to-period change in those items (in thousands):

​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Three Months Ended June 30, | ​ | Period-to-
​ |  | 2025 |  | 2024 |  | Period Change
Operating expenses: |  | ​ |  |  | ​ |  |  | ​ |
Research and development | ​ | $ | 25,945 | ​ | $ | 20,709 | ​ | $ | 5,236
General and administrative | ​ | ​ | 9,875 | ​ | ​ | 8,094 | ​ | ​ | 1,781
Total operating expenses | ​ |  | 35,820 | ​ |  | 28,803 | ​ |  | 7,017
Loss from operations | ​ |  | (35,820) | ​ |  | (28,803) | ​ |  | (7,017)
Other income, net | ​ |  | 2,768 | ​ |  | 4,631 | ​ |  | (1,863)
Net loss | ​ | $ | (33,052) | ​ | $ | (24,172) | ​ | $ | (8,880)

​

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Research and Development Expenses

Research and development expenses increased by $5.2 million to $25.9 million for the three months ended June 30, 2025 from $20.7 million for the three months ended June 30, 2024, an increase of 25%. The increase in research and development expenses was attributable to:

| ● | a $3.1 million increase in navenibart expenses related to the support of ALPHA-ORBIT;

| ● | a $2.2 million increase in employee expenses, partially due to a $0.7 million increase in stock-based compensation expenses and company growth to support the advancement of our programs; and

| ● | a $0.3 million increase in expenses for other programs; offset by

| ● | a $0.4 million decrease in consulting and professional services expenses.

General and Administrative Expenses

General and administrative expenses increased by $1.8 million to $9.9 million for the three months ended June 30, 2025 from $8.1 million for the three months ended June 30, 2024, an increase of 22%. The increase in general and administrative expenses was attributable to a $1.0 million increase in employee expenses, primarily due to an increase in stock-based compensation expenses and company growth to support the advancement of our programs, a $0.5 million increase in professional services expenses, and a $0.3 million increase in general office, facilities, and other expenses.

Other Income, Net

Other income, net decreased by $1.8 million to $2.8 million for the three months ended June 30, 2025 from $4.6 million for the three months ended June 30, 2024, a decrease of 40%. The decrease was attributable to a decrease in interest-earning assets and lower yields on our interest-earning assets during the three months ended June 30, 2025.

Comparison of the Six Months Ended June 30, 2025 and 2024

The following table summarizes our results of operations for the six months ended June 30, 2025 and 2024, together with the period-to-period change in those items (in thousands):

​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Six Months Ended June 30, | ​ | Period-to-
​ |  | 2025 |  | 2024 |  | Period Change
Operating expenses: |  | ​ |  |  | ​ |  |  | ​ |
Research and development | ​ | $ | 53,731 | ​ | $ | 36,435 | ​ | $ | 17,296
General and administrative | ​ |  | 19,084 | ​ |  | 16,518 | ​ |  | 2,566
Total operating expenses | ​ |  | 72,815 | ​ |  | 52,953 | ​ |  | 19,862
Loss from operations | ​ |  | (72,815) | ​ |  | (52,953) | ​ |  | (19,862)
Other income, net | ​ |  | 6,054 | ​ |  | 8,853 | ​ |  | (2,799)
Net loss | ​ | $ | (66,761) | ​ | $ | (44,100) | ​ | $ | (22,661)

​

Research and Development Expenses

Research and development expenses increased by $17.3 million to $53.7 million for the six months ended June 30, 2025 from $36.4 million for the six months ended June 30, 2024, an increase of 47%. The increase in research and development expenses was attributable to:

| ● | a $7.8 million increase in navenibart expenses, partially due to a $2.2 million milestone payment obligation that was met as the result of the initiation of the ALPHA-ORBIT Phase 3 clinical trial, in addition to expenses related to the support of ALPHA-ORBIT;

| ● | a $4.5 million increase in STAR-0310 expenses, partially due to a $2.0 million milestone payment obligation that was met as the result of the initiation of the Phase 1a clinical trial of STAR-0310, in addition to external research and development expenses and clinical trial costs related to the STAR-0310 Phase 1a trial;

| ● | a $4.0 million increase in employee expenses, partially due to a $1.3 million increase in stock-based compensation expenses and company growth to support the advancement of our programs;

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| ● | a $0.7 million increase in consulting, professional services, and facilities expenses; and

| ● | a $0.3 million increase in expenses for other programs.

General and Administrative Expenses

General and administrative expenses increased by $2.6 million to $19.1 million for the six months ended June 30, 2025 from $16.5 million for the six months ended June 30, 2024, an increase of 16%. The increase in general and administrative expenses was attributable to a $2.2 million increase in employee expenses, primarily due to an increase in stock-based compensation expenses and company growth to support the advancement of our programs, in addition to a $0.5 million increase in general office and facilities expenses, partially offset by a $0.1 million decrease in professional services expenses.

Other Income, Net

Other income, net decreased by $2.8 million to $6.1 million for the six months ended June 30, 2025 from $8.9 million for the six months ended June 30, 2024, a decrease of 32%. The decrease was attributable to a decrease in interest-earning assets and lower yields on our interest-earning assets during the six months ended June 30, 2025.

Liquidity and Capital Resources

From our inception through June 30, 2025, we raised an aggregate of $839.2 million through equity financings including private placements of preferred stock before we became a public company, our private placement of preferred stock in February 2021 and registered offerings of our common stock, including our at-the-market offering programs.

As of June 30, 2025, we had $259.2 million in cash, cash equivalents and short-term investments, which, together with the Kaken upfront payment and expected reimbursement of a portion of our Phase 3 program costs, we expect will enable us to fund our operating expenses and capital expenditure requirements into 2028. Our current operating plan includes (i) for navenibart, support for all program activities through completion of our ALPHA-ORBIT Phase 3 trial, including activities related to the planned ORBIT-EXPANSE long-term trial and Phase 3 development and testing of drug device combinations, and (ii) for STAR-0310, the completion of the ongoing Phase 1a clinical trial of healthy subjects. We have based this estimate on assumptions that may prove to be wrong, and we could use our available capital resources sooner than we currently expect. Furthermore, our operating plan may change as a result of many factors currently unknown to us, and we may need to seek additional financing to fund our long-term operations sooner than planned.

Advancing the development and commercialization of navenibart, any drug device combination for navenibart, STAR-0310 or any future product candidates will require a significant amount of capital, and our existing cash, cash equivalents and short-term investments, including the Kaken upfront payment and the expected reimbursement of a portion of our Phase 3 program costs, will not be sufficient to enable us to fund the completion of development of any of our product candidates, including navenibart, any drug device combination for navenibart, STAR-0310 or any future product candidate. In addition, navenibart, STAR-0310 or any future product candidates, if approved, may not achieve commercial success. Our commercial revenues, if any, will be derived from sales of product candidates that we do not expect to be commercially available for years, if at all. Accordingly, we will need to obtain substantial additional funding to complete the development and commercialization of navenibart, any drug device combination for navenibart, STAR-0310 or any future product candidates and support our continuing operations, future clinical trials and expansion of our pipeline. Adequate additional financing may not be available to us on acceptable terms, or at all. The terms of any financing may adversely affect the holdings or the rights of our stockholders. General economic conditions, both inside and outside the United States, including heightened inflation, the global trade environment, capital market instability and volatility, interest rate and currency rate fluctuations and economic slowdown or recession as well as pandemics, epidemics and geopolitical events, including civil or political unrest (such as the Ukraine-Russian war and the conflict in the Middle East), may have a significant impact on the availability of funding sources and the terms on which any funding may be available. In addition, market instability and volatility, high levels of inflation and interest rate fluctuations may increase our cost of financing or restrict our access to potential sources of future liquidity. If we fail to raise capital as, and when, needed, we may be unable to continue our operations at planned levels and be forced to modify our business strategies and reduce or terminate our operations. Although we will continue to pursue these plans, there is no assurance that we will be successful in obtaining sufficient funding on terms acceptable to us to fund continuing operations when needed or at all.

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At-the-Market Offerings

In June 2021, we entered into an Open Market Sale AgreementSM with Jefferies LLC, or Jefferies, pursuant to which we could issue and sell shares of common stock under an at-the-market offering program, or the 2021 ATM Program, which was completed in the first quarter of 2024. In March 2024, we entered into a new Open Market Sale AgreementSM with Jefferies, pursuant to which we are able to issue and sell up to $150.0 million of shares of common stock under an at-the-market offering program, which we refer to as the 2024 ATM Program, and, collectively with the 2021 ATM Program, as the ATM Programs. We pay Jefferies commissions of up to 3% of the gross proceeds from any common stock sold through the ATM Programs. There was no activity in the 2024 ATM Program during the six months ended June 30, 2025 and 2024. During the six months ended June 30, 2024, we sold an aggregate of 2,945,806 shares of common stock under the 2021 ATM Program for gross proceeds of $20.6 million and net proceeds of $20.0 million.

Cash Flows

Comparison of the Six Months Ended June 30, 2025 and 2024

The following table provides information regarding our cash flows for the six months ended June 30, 2025 and 2024 (in thousands):

​

​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Six Months Ended June 30,
​ |  | 2025 |  | 2024
Net cash used in operating activities | ​ | $ | (70,076) | ​ | $ | (35,885)
Net cash provided by (used in) investing activities | ​ |  | 86,575 | ​ |  | (194,334)
Net cash provided by financing activities | ​ |  | — | ​ |  | 141,901
Net increase (decrease) in cash, cash equivalents and restricted cash | ​ | $ | 16,499 | ​ | $ | (88,318)

​

Net Cash Used in Operating Activities

Net cash used in operating activities was $70.1 million for the six months ended June 30, 2025 and consisted primarily of a net loss of $66.8 million in addition to a $10.3 million net increase in net assets, partially offset by $7.0 million of total net non-cash items. The net increase in net assets consisted of an increase in prepaid expenses and other assets of $8.6 million, a decrease in accounts payable of $3.6 million, and a decrease in operating lease liability of $0.6 million partially offset by an increase in accrued expenses of $2.5 million. Total net non-cash items consisted primarily of stock-based compensation expense of $8.2 million, a decrease to our right-of-use asset of $0.6 million, and depreciation of $0.1 million partially offset by accretion of the discount/premium on investment securities of $1.9 million.

Net cash used in operating activities was $35.9 million for the six months ended June 30, 2024 and consisted primarily of a net loss of $44.1 million adjusted for stock-based compensation expense of $6.2 million, partially offset by accretion of the discount/premium on investment securities of $2.5 million, and a decrease in net assets of $4.1 million, which resulted primarily from an increase in accrued expenses of $3.1 million, an decrease in prepaid expenses and other assets of $0.5 million, an increase in accounts payable of $0.8 million, and a net increase in operating lease liability of $0.3 million.

Net Cash Provided by (Used in) Investing Activities

Net cash provided by investing activities was $86.6 million for the six months ended June 30, 2025 and consisted of sales and maturities of short-term investments of $1.4 billion, partially offset by purchases of short-term investments of $1.3 billion as the proceeds from maturities from short-term investments were reinvested, and purchases of property and equipment of $0.6 million.

Net cash used in investing activities was $194.3 million for the six months ended June 30, 2024 and consisted primarily of purchases of short-term investments of $2.4 billion, partially offset by sales and maturities of short-term investments of $2.2 billion as the proceeds from maturities from short-term investments were reinvested.

Net Cash Provided by Financing Activities

There was no cash provided by financing activities for the six months ended June 30, 2025.

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Net cash provided by financing activities was $141.9 million for the six months ended June 30, 2024, which was attributable to net proceeds of $117.2 million from an underwritten offering of 10,340,000 shares of our common stock in February 2024, net proceeds of $20.0 million from the 2021 ATM Program and proceeds from exercises of stock options and warrants of $4.7 million.

Funding Requirements

Our primary uses of capital are for clinical costs, manufacturing costs for clinical materials, third-party preclinical and clinical research and development services, compensation and related expenses, legal and other regulatory expenses, and general overhead.

As of June 30, 2025, we had an accumulated deficit of $741.6 million. We have been primarily involved with research and development activities and have incurred operating losses and negative cash flows from operations since our inception.

Based on our current operating plan, we expect that our existing cash, cash equivalents and short-term investments, together with the Kaken upfront payment and expected reimbursement of a portion of our Phase 3 program costs, will enable us to fund our operating expenses and capital expenditure requirements into 2028. Our current operating plan includes (i) for navenibart, support for all program activities through completion of our ALPHA-ORBIT Phase 3 trial, including activities related to the planned ORBIT-EXPANSE long-term trial and Phase 3 development and testing of drug device combinations, and (ii) for STAR-0310, the completion of the ongoing Phase 1a clinical trial of healthy subjects. Our estimate as to how long we expect our cash, cash equivalents and short-term investments to be able to fund our operations is based on assumptions that may prove to be wrong, and we could use our available capital resources sooner than we currently expect. Because of the numerous risks and uncertainties associated with research, development and commercialization of biotechnology products, we are unable to estimate the exact amount of our operating capital requirements. Further, changing circumstances, some of which may be beyond our control, could cause us to consume capital significantly faster than we currently anticipate, and we may need to seek additional funds sooner than planned. Our future funding requirements will depend on many factors, including:

| ● | the progress, timing, costs and results of clinical trials of, and research and preclinical development efforts for navenibart, any drug device combination for navenibart, STAR-0310, and any future product candidates, including potential future clinical trials;

| ● | our ability to enter into and the terms and timing of any collaborations, licensing or other arrangements that we may establish;

| ● | the number and characteristics of future product candidates that we pursue and their development requirements;

| ● | the outcome, timing and costs of seeking regulatory approvals;

| ● | the costs of commercialization activities for any of our product candidates that receive marketing approval to the extent such costs are not the responsibility of any future collaborators, including the costs and timing of establishing product sales, marketing, market access, distribution, supply chain and manufacturing capabilities, and scaling up the manufacturing of drug substance and drug product to clinical and commercial scale and developing a drug device combination, if applicable, securing all raw materials necessary to conduct such scale-up and successfully completing all other activities related thereto;

| ● | if we obtain marketing approval of any of our product candidates, revenue, if any, received from commercial sales of our product candidates;

| ● | if we obtain marketing approval of any of our product candidates, our ability to successfully compete against other approved products that are approved or used as treatments for the indications for which our products are approved, including with respect to navenibart in HAE and STAR-0310 in AD;

| ● | our headcount growth and associated costs;

| ● | the amount and timing of future milestone and royalty payments potentially payable to Ichnos pursuant to the Ichnos License Agreement covering STAR-0310 and our research services agreement related to navenibart;

| ● | the costs of preparing, filing and prosecuting patent applications, maintaining and protecting our intellectual property rights and defending against intellectual property related claims; and

| ● | the costs of operating as a public company.

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Identifying potential product candidates and conducting preclinical testing and clinical trials is a time-consuming, expensive and uncertain process that takes years to complete, and we may never generate the necessary data or results required to obtain marketing approval and achieve product sales. In addition, navenibart, including any drug device combination for navenibart, STAR-0310 or any future product candidates, if approved, may not achieve commercial success. Our commercial revenues, if any, will be derived from sales of medicines that we do not expect to be commercially available for years, if at all. Accordingly, we will need to continue to rely on additional financing to achieve our business objectives. Adequate additional financing may not be available to us on acceptable terms, or at all.

Until such time, if ever, as we can generate substantial product revenues, we expect to finance our cash needs through a combination of equity offerings, debt financings, collaborations, strategic alliances and licensing arrangements. We do not have any committed external source of funds. To the extent that we raise additional capital through the sale of equity or convertible debt securities, our stockholders’ ownership interests will be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect our stockholders’ rights. Debt financing, if available, would result in periodic payment obligations and may involve agreements that include restrictive covenants that limit our ability to take specific actions, such as incurring debt, making capital expenditures or declaring dividends, that could adversely impact our ability to conduct our business.

If we raise funds through collaborations, strategic alliances or licensing arrangements with third parties, we may have to relinquish valuable rights to our technologies, future revenue streams, research programs or product candidates or to grant licenses on terms that may not be favorable to us. If we are unable to raise additional funds when needed, we may be required to delay, limit, reduce or terminate our product development or future commercialization efforts or grant rights to develop and market product candidates that we would otherwise prefer to develop and market ourselves.

Material Cash Requirements from Known Contractual Obligations

As of June 30, 2025, our material contractual obligations consisted of our sublease which commenced on June 1, 2024, pursuant to which we are required to make monthly payments of $0.1 million, effective September 1, 2024 until its expiration on November 30, 2028, in addition to payment obligations of $2.2 million for specified certain clinical milestones related to the ALPHA-ORBIT Phase 3 clinical trial of navenibart met during the three months ended March 31, 2025 and paid in April 2025. For information related to our future commitments relating to our sublease, research agreements and license agreements, see Note 6, “Leases” and Note 7, “Commitments”, of our condensed consolidated financial statements.

We enter into agreements in the normal course of business with CROs for clinical trials, with third-party manufacturers for clinical supplies and with vendors for preclinical research studies and other services and products for operating purposes. The contracts are cancelable at any time by us, generally upon 30 to 90 days’ prior written notice to the counterparty, and we believe that our non-cancelable obligations under these agreements are not material.

Our license agreement with Ichnos, which covers STAR-0310, includes potential milestone payments, tiered royalties and other obligations that are dependent upon the development of products using the intellectual property licensed under the agreement and contingent upon the achievement of development or regulatory approval milestones, as well as commercial milestones. We are also party to a research services agreement, which covers navenibart, that includes potential milestone payments contingent upon the achievement of regulatory or commercial milestones. The potential obligations in our license agreement and research service agreement are contingent upon future events and the timing and likelihood of such potential obligations are not known with certainty. For further information regarding these agreements, see Note 7, “Commitments”, of our condensed consolidated financial statements and Note 1, “Nature of Business” in our 2024 Annual Report on Form 10-K.

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Item 4. Controls and Procedures

Management’s Evaluation of our Disclosure Controls and Procedures

We maintain disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, or the Exchange Act) that are designed to ensure that information required to be disclosed in the reports that we file or submit under the Exchange Act is (1) recorded, processed, summarized, and reported within the time periods specified in the U.S. Securities and Exchange Commission’s rules and forms and (2) accumulated and communicated to our management, including our principal executive officer and principal financial officer, as appropriate, to allow timely decisions regarding required disclosure.

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As of June 30, 2025, our management, with the participation of our principal executive officer and principal financial officer, evaluated the effectiveness of our disclosure controls and procedures as of the end of the period covered by this Quarterly Report on Form 10-Q. Our management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives, and management necessarily applies its judgment in evaluating the cost-benefit relationship of possible controls and procedures. Our principal executive officer and principal financial officer have concluded based upon the evaluation described above that, as of June 30, 2025, our disclosure controls and procedures were effective at the reasonable assurance level.

Changes in Internal Control over Financial Reporting

There were no changes in our internal control over financial reporting that occurred during the period covered by this Quarterly Report on Form 10-Q that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

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PART II – OTHER INFORMATION

Item 1A. Risk Factors

The risk factors under Part I, Item 1A, “Risk Factors” in our Annual Report on Form 10-K for the fiscal year ended December 31, 2024 are hereby supplemented with the following additional risk factors:

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Our license agreement with Kaken Pharmaceutical Co., Ltd., and any future collaborations, may not lead to the successful development or regulatory approval of product candidates or commercialization of products. Collaborators may have competing priorities, conflicting incentives, or different views than us on key decisions, including appropriate program spending, that may hamper or delay our development and commercialization efforts or increase our costs. We may not realize the benefits of our collaborations or our business may be adversely affected if any of our collaborators fails to perform its obligations or terminates our collaboration.

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Our drug development programs and the potential commercialization of our product candidates will require substantial additional cash to fund expenses. We have collaborated and may in the future decide to collaborate with pharmaceutical and biotechnology companies for the development and potential commercialization of our product candidates in some or all markets. For example, we have entered into a license agreement with Kaken Pharmaceutical, Co., Ltd., or Kaken, pursuant to which we granted Kaken an exclusive license to develop, package, and commercialize navenibart for the prevention HAE attacks in humans in Japan. Pursuant to the terms of the License Agreement, Kaken will provide support for our ALPHA-ORBIT Phase 3 trial in Japan, be responsible for regulatory submissions in Japan, and reimburse the Company for a portion of the costs of the navenibart Phase 3 program. Kaken is obligated to use commercially reasonable efforts to obtain regulatory approval and reimbursement approval for, and commercialize, at least one licensed product in the license field in Japan.

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Our existing license agreement with Kaken and future collaborations, if any, may not lead to the successful development and commercialization of any products. Our collaborators face both the same challenges and hurdles that we would face in the development and commercialization of product candidates if we were engaged in the activities solely ourselves, as well as additional challenges related to operating under a collaboration. Collaboration agreements may not lead to development or commercialization of product candidates in the most efficient manner or at all.

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If we enter into collaborations for the development and commercialization of a product candidate, we will have limited control over the amount and timing of resources that our collaborators will dedicate to the development or commercialization of such product candidates. Our ability to generate revenues from these arrangements will depend on any collaborators’ abilities to successfully perform the functions assigned to them in these arrangements. For example, if navenibart is approved in Japan, and Kaken fails to perform its obligations under or terminates the license agreement, we may seek a different collaboration arrangement with a new commercialization partner, which could cause a disruption in market penetration, if achieved at all, result in us incurring increased expenses and negatively impact our ability to market and sell our product in a target market. The efforts under our license agreement with Kaken may not be successful and we may never receive any milestone payments or royalty payments from Kaken. In addition, any future collaborators may have the right to abandon research or development projects and terminate applicable agreements, including funding obligations, prior to or upon the expiration of the agreed upon terms. Collaborations involving product candidates pose a number of risks, including the following:

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●collaborators have significant discretion in determining the efforts and resources that they will apply to these collaborations;
●collaborators may not perform their obligations as expected;
●collaborators may not pursue development and commercialization of a product candidate or may elect not to continue or renew development or commercialization programs, based on clinical trial results, changes in the market or competitive landscape, changes in the collaborators’ strategic focus or available funding or external factors, such as an acquisition, that divert resources or create competing priorities;
●collaborators may delay clinical trials, provide insufficient funding for a clinical trial program, stop a clinical trial or abandon a product candidate, repeat or conduct new clinical trials or require a new formulation of a product candidate for clinical testing;

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●a collaborator with marketing and distribution rights to one or more products may not commit sufficient resources to the marketing and distribution of such product or products;
●disagreements with collaborators, including disagreements over proprietary rights, contract interpretation or the preferred course of development, might cause delays or termination of the research, development or commercialization of product candidates, might lead to additional responsibilities for us with respect to product candidates, or might result in litigation or arbitration, any of which would be time-consuming and expensive;
●collaborators may not properly maintain or defend our intellectual property rights or may use our proprietary information in such a way as to invite litigation that could jeopardize or invalidate our intellectual property or proprietary information or expose us to potential litigation;
●collaborators may infringe the intellectual property rights of third parties, which may expose us to litigation and potential liability; and
●collaborations may be terminated and, if terminated, may result in negative publicity for our product candidate and the need for additional capital to pursue further development or commercialization of the applicable product candidates.

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If Kaken or any future collaborator of ours is involved in a business combination or a sale or other transaction involving our collaboration, it or the party with which it entered into a business combination, sale or other transaction could decide to delay, diminish or terminate the development or commercialization of any product candidate licensed to it by us.

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In addition, under most collaborations, including our existing license with Kaken, a certain degree of control in decision-making is transferred to or shared with our collaborators, including with respect to pricing and reimbursement decisions. Our collaborators may use their decision-making authority to make decisions that could delay, decrease the potential of, or otherwise adversely impact, development and commercialization of our product candidates, including pricing and reimbursement decisions that may impact the pricing and reimbursement levels of such product candidates in other markets. Similarly, where we share decision-making authority, the need to gain alignment on decisions may slow or impede advancement of our programs and cause us not to be able to meet our timelines or achieve our goals. Our collaborators may independently develop, or develop with a competitor, competitive products or may believe that product candidates being evaluated in the collaboration could be competitive with the collaborator’s own products. In addition, if we depend on collaborators for capabilities and funding for major product development efforts globally or in key territories then our business may be adversely affected if our collaborator fails to perform its obligations under the agreement or the collaboration terminates.

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We may seek to establish additional collaborations and, if we are not able to establish them on commercially reasonable terms, we may have to alter our development and commercialization plans.

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The development and commercialization of product candidates require substantial cash to fund expenses. In addition to our license with Kaken, we may seek one or more additional collaborators for the development and commercialization of navenibart, STAR-0310 or any other future product candidates. Likely collaborators may include large and mid-size pharmaceutical companies, regional and national pharmaceutical companies and biotechnology companies.

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Collaborations are complex and time-consuming to negotiate and document. Further, there have been a significant number of business combinations among large pharmaceutical companies that have resulted in a reduced number of potential future collaborators. In addition, any collaboration agreements that we enter into in the future may contain restrictions on our ability to enter into potential collaborations or to otherwise develop specified compounds or biologics.

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We face significant competition in seeking appropriate collaborators and strategic partners. Whether we reach a definitive agreement for a collaboration or strategic partnership will depend, among other things, upon our assessment of the other party’s resources and expertise, the terms and conditions of the proposed transaction and the proposed party’s evaluation of a number of factors. Those factors may include the potential differentiation of ours or a partner’s product candidate from competing product candidates, design or results of clinical trials, the likelihood of approval by the FDA or comparable foreign regulatory authorities and the regulatory pathway for any such approval, the potential market for the product candidate, the costs and complexities of manufacturing and delivering the product to patients and the potential of competing products. The collaborator or strategic partner may also be considering alternative transaction types and structures that may be more attractive than the one with us.

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We may not be able to negotiate collaborations on a timely basis, on acceptable terms, or at all. If we are unable to do so, we may have to curtail the development of the product candidate for which we are seeking to collaborate, reduce or delay its development program or one or more of our other development programs, delay its potential commercialization or reduce the scope of any sales or marketing activities, or increase our expenditures and undertake development or commercialization activities at our own expense. If we elect to increase our expenditures to fund development or commercialization activities on our own, we may need to obtain additional capital, which may not be available to us on acceptable terms or at all. If we do not have sufficient funds, we may not be able to further develop the product candidate or bring it to market and generate product revenue.

Changes in U.S. trade policy could have a material adverse impact on our business, financial condition and results of operations.

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President Trump’s administration has imposed a series of tariffs on U.S. trading partners. On April 2, 2025, an executive order issued by the administration announced a “baseline” reciprocal tariff of 10% on all U.S. trading partners effective April 5, 2025, and higher individualized reciprocal tariffs on 57 countries (with certain product exemptions for pharmaceutical-related imports, among others). The administration has also imposed a 25% tariff on products of Canada and Mexico that are not covered by the United States-Mexico-Canada Agreement, or USMCA, in addition to an additional 20% tariff on products of China. In response, several countries threatened retaliatory measures including Canada and China who then imposed retaliatory tariffs. Prior to when the country-specific reciprocal tariffs were scheduled to take effect, the U.S. delayed the effective date of such tariffs for all countries except China. The 10% baseline reciprocal tariff on all countries remains in effect, in addition to the tariffs on China (which, at one point, increased to a minimum of 145%, but were 20% as of August 1, 2025) and Canada and Mexico (which were 25% as of August 1, 2025 for goods that are not covered by the USMCA).

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Separately, on April 16, 2025, the U.S. Department of Commerce, or the Commerce Department, announced an investigation under Section 232 of the Trade Expansion Act of 1962 into imports of pharmaceuticals and pharmaceutical ingredients, including finished drug products, medical countermeasures, critical inputs such as active pharmaceutical ingredients, and key starting materials, and derivative products of those items. The investigation will examine the impact of these imports on U.S. national security culminating in a decision by the President whether to take action to remedy any identified threats, including by imposing additional tariffs. The statute provides that the Commerce Department report must be completed within 270 days of initiation and that the President must decide whether to act within 90 days of receiving the report.

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We are assessing the impact of the tariffs on our business and will continue to monitor these developments closely. We cannot yet predict the long-term effect of the recently imposed U.S. tariffs on our business, or the extent to which other countries will impose quotas, duties, tariffs, taxes or other similar restrictions that would impact our business in the future, nor can we predict future trade policy or the terms of any renegotiated trade agreements and their impact on our business, or the results of the Section 232 investigation undertaken by the Commerce Department.

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However, as a clinical stage development company that uses third-party contract manufacturers located outside the U.S., including in China, we do anticipate that the proposed tariffs will result in a marginal increase to our clinical manufacturing costs. The imposition of new tariffs or increases in existing tariffs on goods imported from countries where we or our suppliers operate could result in increased costs for raw materials, components, or finished goods. Additionally, retaliatory tariffs imposed by other countries on U.S. exports could adversely impact our business. Supply chain disruptions and delays as a result of any new tariff policies or trade restrictions, including the inability of our third-party contractors to obtain necessary raw materials for the manufacturing of drug substance or drug product for our product candidates, could also negatively impact our cost of materials and production processes, and potentially delay the development, testing, clinical trials and commercialization of our product candidates. Political tensions as a result of trade policies could reduce trade volume, investment, technological exchange, and other economic activities between major international economies, resulting in a material adverse effect on global economic conditions and the stability of global financial markets, which could in turn have a material adverse impact on our business, financial condition or results of operations. The extent and duration of increased tariffs and the resulting impact on general economic conditions and on our business are uncertain and depend on various factors, such as negotiations between the U.S. and affected countries, the responses of other countries or regions, exemptions or exclusions that may be granted, availability and cost of alternative sources of supply, and demand for our products in affected markets. If we are unable to mitigate these risks, our financial performance and growth prospects could be negatively affected.

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Disruptions at the U.S. Food and Drug Administration, or FDA, and other government agencies from funding cuts, personnel losses, regulatory reform, government shutdowns and other developments could negatively impact our business.

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The FDA plays an important role in the development of our product candidates by providing guidance on our clinical development programs and reviewing our regulatory submissions, including Investigational New Drug Applications, requests for special designations and marketing applications. If these oversight and review activities are disrupted, then correspondingly our ability to develop and secure timely approval of our product candidates could be impacted in a negative manner.

The recent loss of FDA leadership and personnel, and the planned reorganization of the FDA, could lead to disruptions and delays in FDA guidance, and the review and approval of our product candidates. Pursuant to an executive order issued by President Trump, the Secretary of the Department of Health and Human Services, or HHS, which includes the FDA, announced on March 27, 2025, a reorganization and Reduction in Force, or RIF, across HHS and thousands of employees at the FDA were fired in April 2025. Additional budget cuts are anticipated across HHS and FDA for the 2026 federal fiscal year. For example, earlier this year, we were informed by the FDA that they would be delayed in providing guidance (that we subsequently received) to us on certain navenibart Phase 3 trial documentation as a result of limited resources and the FDA team’s extensive workloads. There can be no assurance that additional disruptions or delays would not adversely impact our development timelines.

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Further, while the FDA’s review of marketing applications and other activities for new drugs and biologics is largely funded through the user fee program established under the Prescription Drug User Fee Act, or PDUFA, it remains unclear how the administration’s RIF and budget cuts will impact this program and the ability of the FDA to provide guidance and review our product candidates in a timely manner. For example, while the FDA RIF did not specifically target FDA reviewers, many operations, administrative and policy staff that help support such reviews were affected and those losses could lead to delays in PDUFA reviews and related activities. In addition, while currently unclear, there is a risk that the RIF and budget cutbacks could threaten the integrity of the PDUFA program itself. That is because, for the FDA to obligate user fees collected under PDUFA in the first place, a certain amount of non-user fee appropriations must be spent on the process for the review of applications plus certain other costs during the same fiscal year.

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There is substantial uncertainty as to how regulatory reform measures being implemented by the Trump administration across the government will impact the FDA. For example, since taking office, President Trump has issued a number of executive orders that could have a significant impact on the manner in which the FDA conducts its operations and engages in regulatory and oversight activities. These include E.O. 14192, “Unleashing Prosperity Through Deregulation,” January 31, 2025; E.O. 14212, “Establishing the President’s Make America Healthy Again Commission,” February 13, 2025; and E.O. 14219, “Ensuring Lawful Governance and Implementing the President’s ‘Department of Government Efficiency’ Deregulatory Initiative,” February 21, 2025. In addition, as described below, U.S. government shutdowns have previously impacted the FDA’s activities. Accordingly, if any of the foregoing developments or other developments impact the ability of the FDA to provide us with guidance regarding our clinical development programs or delay the agency’s review and processing of our regulatory submissions, our business would be negatively impacted.

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There is also substantial uncertainty as to how regulatory reform measures being implemented by the administration, and other political developments, such as government shutdowns or work stoppages, would impact other U.S. regulatory agencies, such as the U.S. Securities and Exchange Commission, or SEC, U.S. Patent and Trademark Office, and the Centers for Medicare & Medicaid Services, on which our operations rely. For example, over the last several years, the U.S. government has shut down several times and certain regulatory agencies have had to furlough critical employees and stop critical activities. If a prolonged government shutdown occurs that impacts any of the regulatory agencies upon which our business relies, it could significantly impact our business and, with respect to the SEC, our ability to access the public markets and obtain necessary capital in order to properly capitalize and continue our operations.

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Item 5. Other Information

N o n e of our directors or officers adopted or terminated a Rule 10b5-1 trading arrangement or a non-Rule 10b5-1 trading arrangement (each as defined in Item 408 of Regulation S-K) during the second quarter of 2025.

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Item 6. Exhibits

The exhibits filed as part of this Quarterly Report on Form 10-Q are set forth on the Exhibits Index below:

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Exhibit Number |  | Exhibit
10.1* | ​ | Second Amended and Restated 2015 Stock Incentive Plan, as amended
31.1* |  | Certification of principal executive officer pursuant to Rule 13a-14(a) or Rule 15d-14(a) of the Securities Exchange Act of 1934, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002
31.2* |  | Certification of principal financial officer pursuant to Rule 13a-14(a) or Rule 15d-14(a) of the Securities Exchange Act of 1934, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002
32.1** |  | Certification pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of The Sarbanes-Oxley Act of 2002, by the Registrant’s principal executive officer and principal financial officer
101.INS |  | Inline XBRL Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document
101.SCH |  | Inline XBRL Taxonomy Extension Schema Document
101.CAL |  | Inline XBRL Taxonomy Calculation Linkbase Document
101.DEF |  | Inline XBRL Taxonomy Extension Definition Linkbase Document
101.LAB |  | Inline XBRL Taxonomy Label Linkbase Document
101.PRE | ​ | Inline XBRL Taxonomy Presentation Linkbase Document
104 | ​ | Cover Page Data File (the cover page XBRL tags are embedded within the iXBRL document).

* Filed herewith.

** Furnished herewith.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

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| Astria Therapeutics, Inc.
Date: August 12, 2025 | By: | /s/ NOAH C. CLAUSER
|  | Noah C. Clauser
|  | Chief Financial Officer (Principal Financial Officer)

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