License and Collaboration Arrangements	9 Months Ended
Sep. 30, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
License and Collaboration Arrangements	4. License and Collaboration Arrangements Out-License Agreements Zai Lab Entasis entered into a license and collaboration agreement with Zai Lab (Shanghai) Co., Ltd. (“Zai Lab”) (Nasdaq: ZLAB), pursuant to which Zai Lab licensed exclusive rights to durlobactam and SUL-DUR, in the Asia-Pacific region (“the Zai Agreement”). Under the terms of the Zai Agreement, Zai Lab shall fund most of the registrational clinical trial costs in China for SUL-DUR, with the exception of Phase 3 patient drug supply of licensed products. Zai Lab shall conduct development activities and plan and obtain regulatory approval in a specified number of countries in the Asia-Pacific region beyond China after receipt of regulatory approval of a licensed product in China. Zai Lab is also solely responsible for commercializing licensed products in the Asia-Pacific region and shall commercialize licensed products for which it has obtained regulatory approval. We are obligated to supply Zai Lab with the licensed products for clinical development and for commercial use for a certain period unless Zai Lab notifies otherwise. Zai Lab may take over manufacturing responsibilities for its own commercialization activities within a specified time period following the effective date of the Zai Agreement. We are eligible to receive up to an aggregate of $91.0 million in research and development support payments and development, regulatory and sales milestone payments related to SUL-DUR, imipenem and other combinations with the licensed products. Zai Lab shall pay us a tiered royalty equal to from a high-single digit to low-double digit percentage based on annual net sales of licensed products in the territory, subject to specified reductions for the market entry of competing products, loss of patent coverage of licensed products and for payments owed to third parties for additional rights necessary to commercialize licensed products in the territory. Payments received for research support and reimbursable clinical trial costs are recorded as a reduction to research and development expense during the period in which the qualifying expenses are incurred. Such amounts recorded for the three and nine months ended September 30, 2025 and 2024 were not material. SUL-DUR was approved by China’s National Medical Products Administration in May 2024 and was launched by Zai Lab in mainland China in January 2025. Royalties under this arrangement based on the product sales were $0.4 million and $1.5 million for the three and nine months ended September 30, 2025, respectively. We recognized $8.0 million in license revenue for the nine months ended September 30, 2024 under this agreement as a result of the achievement of a regulatory milestone. In April 2024, we entered into an amendment to the Zai Agreement (the “Amended Zai Agreement”), pursuant to which Zai Lab shall share costs associated with certain new manufacturing and technology transfer activities for XACDURO® (the “Services”), which were not contemplated under the Zai Agreement and are crucial for regulatory approval in the Asia-Pacific region. Under the Amended Zai Agreement, we recognized $0.4 million and $1.0 million in license revenue for the three and nine months ended September 30, 2025, respectively, and $0.8 million and $7.3 million for the three and nine months ended September 30, 2024, respectively. As of September 30, 2025 and December 31, 2024, outstanding amounts under this amendment of $1.4 million and $1.6 million, respectively, were included in “Accounts receivable” in our unaudited condensed consolidated balance sheets. We entered into an interim supply agreement with Zai Lab in June 2024, which was amended in February 2025 and August 2025, under which Zai Lab shall purchase XACDURO® inventory (the “Supplied Inventory”) for their commercial use. We recognized $14.9 million and $17.4 million in net product sales for the cost of the Supplied Inventory for the three and nine months ended September 30, 2025, respectively. We recognized $5.5 million in net product sales for the cost of the Supplied Inventory for the three and nine months ended September 30, 2024. Amounts outstanding under this agreement of $7.4 million and $0.6 million are included in “Accounts receivable” in our unaudited condensed consolidated balance sheets as of September 30, 2025 and December 31, 2024, respectively. We have recorded deferred revenue of $10.4 million as of September 30, 2025 and other accrued liabilities of $5.3 million as of December 31, 2024 under this agreement. The amount as of December 31, 2024 was recorded as other accrued liabilities pending finalization of the February and August 2025 amendments mentioned above. We also entered into a manufacturing stage transfer agreement with Zai Lab in June 2024, which was amended in September 2024 (the “Zai Manufacturing Stage Transfer Agreement”). Pursuant to this agreement, Entasis shall provide assistance to Zai Lab for building out Zai Lab's manufacturing site for XACDURO® and be compensated for Entasis' services and associated costs. We recognized license revenue under this agreement of $0.1 million and $1.0 million for the three and nine months ended September 30, 2025, respectively, and $3.4 million for the three and nine months ended September 30, 2024. GARDP Entasis entered into a collaboration agreement with the Global Antibiotic Research and Development Partnership (“GARDP”) for the development, manufacture and commercialization of the product candidate zoliflodacin in certain countries (“the GARDP Collaboration Agreement”). Under the terms of the GARDP Collaboration Agreement, GARDP shall use commercially reasonable endeavors to perform and fully fund the Phase 3 registrational trial, including the manufacture and supply of the product candidate containing zoliflodacin, in uncomplicated gonorrhea. We recorded $0.8 million in reimbursements from GARDP under this agreement as a reduction to research and development expense during the three and nine months ended September 30, 2025. The reimbursable amounts from GARDP for the three and nine months ended September 30, 2024 were not material. In addition, under the GARDP Collaboration Agreement, GARDP was granted a worldwide, fully paid, exclusive and royalty-free license, with the right to sublicense, to use our zoliflodacin technology in connection with GARDP’s development, manufacture and commercialization of zoliflodacin in low-income and specified middle-income countries. We retained commercial rights in all other countries worldwide, including the major markets in North America, Europe and Asia-Pacific. We also retained the right to use and grant licenses to our zoliflodacin technology to perform our obligations under the GARDP Collaboration Agreement and for any purpose other than gonorrhea or community-acquired indications. If we believe that the results of the Phase 3 registrational trial of zoliflodacin would be supportive of an application for marketing approval, we are obligated to use our best efforts to file an application for marketing approval with the FDA within six months of the completion of the trial and to use commercially reasonable endeavors to file an application for marketing approval with the European Medicines Agency (“EMA”). Each party is responsible for using commercially reasonable efforts to obtain marketing authorizations for the product candidate in their respective territories. An application for marketing approval has been filed with the FDA in 2025. PAION Pharma GmbH Pursuant to the PAION AG and PAION Deutschland GmbH (together and individually “PAION”) License, La Jolla granted PAION an exclusive license to commercialize GIAPREZA® and XERAVA® in the European Economic Area, the United Kingdom and Switzerland (collectively, the “PAION Territory”). PAION is currently a subsidiary of the Humanwell Healthcare Group. We are entitled to receive potential commercial milestone payments of up to $109.5 million and double-digit tiered royalty payments. Royalties payable in a given jurisdiction under the PAION License are subject to reduction on account of generic competition and after patent expiration in that jurisdiction. Pursuant to the PAION License, PAION will be solely responsible for the future development and commercialization of GIAPREZA® and XERAVA® in the PAION Territory. PAION is required to use commercially reasonable efforts to commercialize GIAPREZA® and XERAVA® in the PAION Territory. Royalty revenue recognized under this agreement for the three and nine months ended September 30, 2025 were $0.7 million and $1.8 million, respectively. Royalty revenue recognized under this agreement for the three and nine months ended September 30, 2024 was not material. La Jolla also entered into the PAION commercial supply agreement (the “PAION Supply Agreement”) whereby La Jolla supplies PAION a minimum quantity of GIAPREZA® and XERAVA® until the earlier of July 13, 2027, or until a new supply agreement is executed. During the term of the supply agreement, we are reimbursed for direct and certain indirect manufacturing costs at cost. We recognized $1.3 million and $2.7 million in cost reimbursements for the three and nine months ended September 30, 2025, respectively. Cost reimbursements recognized under this agreement for the three and nine months ended September 30, 2024 were not material. Everest Medicines Limited Pursuant to the Everest Medicines Limited (“Everest”) License, La Jolla granted Everest an exclusive license to develop and commercialize XERAVA® for the treatment of complicated intra-abdominal infections (“cIAI”) and other indications in mainland China, Taiwan, Hong Kong, Macau, South Korea, Singapore, the Malaysian Federation, the Kingdom of Thailand, the Republic of Indonesia, the Socialist Republic of Vietnam and the Republic of the Philippines (collectively, the “Everest Territory”). We are eligible to receive sales milestone payments of up to an aggregate of $20.0 million under this agreement. We are also entitled to receive tiered royalties from Everest at percentages in the low double digits on sales, if any, in the Everest Territory of products containing eravacycline. Royalties are payable with respect to each jurisdiction in the Everest Territory until the latest to occur of: (i) the last-to-expire of specified patent rights in such jurisdiction in the Everest Territory; (ii) expiration of marketing or regulatory exclusivity in such jurisdiction in the Everest Territory; or (iii) 10 years after the first commercial sale of a product in such jurisdiction in the Everest Territory. Royalty revenue from Everest recognized for the three months ended September 30, 2025 was immaterial. We recognized $2.0 million in royalty revenue from Everest for the nine months ended September 30, 2025. Royalty revenue recognized for the three and nine months ended September 30, 2024 was $0.6 million and $2.3 million, respectively. La Jolla also entered into the Everest commercial supply agreement (the “Everest Supply Agreement”) whereby La Jolla will supply Everest a minimum quantity of XERAVA® and will transfer to Everest certain XERAVA®-related manufacturing know-how. Under the Everest Supply Agreement, we are reimbursed for direct and certain indirect manufacturing costs at 110% of cost. Revenue recognized under the Everest Supply Agreement for the three and nine months ended September 30, 2025 was not material and $1.8 million, respectively. Revenue recognized under the Everest Supply Agreement for the three and nine months ended September 30, 2024 was $0.9 million and $2.6 million, respectively. In-License Agreements Basilea In December 2024, we entered into an exclusive distribution and license agreement with Basilea, under which we were granted exclusive marketing rights to ZEVTERA® in the U.S. The agreement will remain in effect through the expiration of ZEVTERA®’s market exclusivity in the U.S. in 2034 (the “initial term”)and is subject to automatic renewal unless terminated by either party with prior notice. We paid an upfront fee of $4.0 million, which was recognized as an intangible asset and is being amortized over the initial term of the agreement. Under the agreement, we are required to exclusively purchase ZEVTERA® (in pre-packaging and labeling form) from Basilea for the duration of the term. We are also obligated to pay Basilea tiered royalties ranging from the high-teens to mid-twenties, as well as tiered milestone payments based on annual net sales in the U.S. ZEVTERA® was commercially launched in the U.S. in July 2025. Royalty expense incurred on the sales was immaterial during the three and nine months ended September 30, 2025. George Washington University Pursuant to the George Washington University License (the “GW License”), GW exclusively licensed to La Jolla certain intellectual property rights relating to GIAPREZA®, including the exclusive rights to certain issued patents and patent applications covering GIAPREZA®. Under the GW License, we are obligated to use commercially reasonable efforts to develop, commercialize, market and sell GIAPREZA®. We are obligated to pay a 6% royalty on net sales of GIAPREZA® and 15% on payments received from sublicensees. The obligation to pay royalties under the GW License extends through the last-to-expire patent covering GIAPREZA®. Royalty expense incurred under the GW License for the three and nine months ended September 30, 2025 were $1.1 million and $3.3 million, respectively. Royalty expense incurred for the three and nine months ended September 30, 2024 were $1.0 million and $2.5 million, respectively. Harvard University Pursuant to the Harvard University (“Harvard”) License, Harvard exclusively licensed to La Jolla certain intellectual property rights relating to tetracycline-based products, including XERAVA®, including the exclusive rights to certain issued patents and patent applications covering such products. Under the Harvard License, we are obligated to use commercially reasonable efforts to develop, commercialize, market and sell tetracycline-based products, including XERAVA®. For each product covered by the Harvard License, we are obligated to make certain payments for the following: (i) up to approximately $15.1 million upon the achievement of certain clinical development and regulatory milestones; (ii) a 5% royalty on direct U.S. net sales of XERAVA®; (iii) a single-digit tiered royalty on direct ex-U.S. net sales of XERAVA®, starting at a minimum royalty rate of 4.5%, with step-ups to a maximum royalty of 7.5% based on the achievement of annual net product sales thresholds; and (iv) 20% on payments received from sublicensees. The obligation to pay royalties under this agreement extends through the last-to-expire patent covering tetracycline-based products, including XERAVA®. Royalty expense incurred under the Harvard License for the three and nine months ended September 30, 2025 were $0.3 million and $1.0 million, respectively. Royalty expense incurred for the three and nine months ended September 30, 2024 were $0.3 million and $1.5 million, respectively. Business Transfer and Subscription Agreement with AstraZeneca Entasis entered into a Business Transfer and Subscription Agreement with AstraZeneca, AstraZeneca UK Limited and AstraZeneca Pharmaceuticals LP (collectively, “AstraZeneca”) (the “AstraZeneca Agreement”) in 2015, which was amended and restated through 2018, pursuant to which Entasis obtained, among other things, worldwide rights to durlobactam and zoliflodacin. Under the AstraZeneca Agreement, we are obligated to pay AstraZeneca a one-time milestone payment of $5.0 million within three months of achieving a specified cumulative net sales milestone for durlobactam. We are also obligated to pay AstraZeneca a one-time milestone payment of $10.0 million within two years of achieving the first commercial sale of zoliflodacin. Additionally, we are obligated to pay AstraZeneca tiered, single-digit royalties on the annual worldwide net product sales of durlobactam and, the lesser of tiered, single-digit royalties on the worldwide annual net sales of zoliflodacin and a specified share of the royalties we receive from sublicensees of zoliflodacin. Royalties on sales of zoliflodacin do not include sales by GARDP in low-income and specified middle-income countries as discussed above. Our obligation to make these royalty payments expires on a country-by-country basis for each product upon the later of (i) the 10-year anniversary of the first commercial sale of a product in that country or (ii) the expiration date of the last patent right covering the product in that country. The royalty expense in respect of durlobactam arising from our net product sales of XACDURO® for the three and nine months ended September 30, 2025 and 2024 was not material. Massachusetts Institute of Technology In connection with the asset acquisition described in Note 13, “Asset Acquisition”, in September 2025, we entered into a license agreement with Massachusetts Institute of Technology (“MIT”), under which MIT licensed to us certain patent rights relating to a drug delivery device. Under this agreement, we paid an upfront fee of $0.5 million and are obligated to pay a minimal annual maintenance fee. We are also obligated to pay MIT up to $17.5 million in development, regulatory and sales milestone payments, and pay royalties in a low single-digit percentage on future net sales related to the licensed product.

License and Collaboration Arrangements

9 Months Ended

Sep. 30, 2025

Organization, Consolidation and Presentation of Financial Statements [Abstract]

4. License and Collaboration Arrangements

Out-License Agreements

Zai Lab

Entasis entered into a license and collaboration agreement with Zai Lab (Shanghai) Co., Ltd. (“Zai Lab”) (Nasdaq: ZLAB), pursuant to which Zai Lab licensed exclusive rights to durlobactam and SUL-DUR, in the Asia-Pacific region (“the Zai Agreement”). Under the terms of the Zai Agreement, Zai Lab shall fund most of the registrational clinical trial costs in China for SUL-DUR, with the exception of Phase 3 patient drug supply of licensed products. Zai Lab shall conduct development activities and plan and obtain regulatory approval in a specified number of countries in the Asia-Pacific region beyond China after receipt of regulatory approval of a licensed product in China. Zai Lab is also solely responsible for commercializing licensed products in the Asia-Pacific region and shall commercialize licensed products for which it has obtained regulatory approval. We are obligated to supply Zai Lab with the licensed products for clinical development and for commercial use for a certain period unless Zai Lab notifies otherwise. Zai Lab may take over manufacturing responsibilities for its own commercialization activities within a specified time period following the effective date of the Zai Agreement.

We are eligible to receive up to an aggregate of $91.0 million in research and development support payments and development, regulatory and sales milestone payments related to SUL-DUR, imipenem and other combinations with the licensed products. Zai Lab shall pay us a tiered royalty equal to from a high-single digit to low-double digit percentage based on annual net sales of licensed products in the territory, subject to specified reductions for the market entry of competing products, loss of patent coverage of licensed products and for payments owed to third parties for additional rights necessary to commercialize licensed products in the territory. Payments received for research support and reimbursable clinical trial costs are recorded as a reduction to research and development expense during the period in which the qualifying expenses are incurred. Such amounts recorded for the three and nine months ended September 30, 2025 and 2024 were not material. SUL-DUR was approved by China’s National Medical Products Administration in May 2024 and was launched by Zai Lab in mainland China in January 2025. Royalties under this arrangement based on the product sales were $0.4 million and $1.5 million for the three and nine months ended September 30, 2025, respectively. We recognized $8.0 million in license revenue for the nine months ended September 30, 2024 under this agreement as a result of the achievement of a regulatory milestone.

In April 2024, we entered into an amendment to the Zai Agreement (the “Amended Zai Agreement”), pursuant to which Zai Lab shall share costs associated with certain new manufacturing and technology transfer activities for XACDURO® (the “Services”), which were not contemplated under the Zai Agreement and are crucial for regulatory approval in the Asia-Pacific region. Under the Amended Zai Agreement, we recognized $0.4 million and $1.0 million in license revenue for the three and nine months ended September 30, 2025, respectively, and $0.8 million and $7.3 million for the three and nine months ended September 30, 2024, respectively. As of September 30, 2025 and December 31, 2024, outstanding amounts under this amendment of $1.4 million and $1.6 million, respectively, were included in “Accounts receivable” in our unaudited condensed consolidated balance sheets.

We entered into an interim supply agreement with Zai Lab in June 2024, which was amended in February 2025 and August 2025, under which Zai Lab shall purchase XACDURO® inventory (the “Supplied Inventory”) for their commercial use. We recognized $14.9 million and $17.4 million in net product sales for the cost of the Supplied Inventory for the three and nine months ended September 30, 2025, respectively. We recognized $5.5 million in net product sales for the cost of the Supplied Inventory for the three and nine months ended September 30, 2024. Amounts outstanding under this agreement of $7.4 million and $0.6 million are included in “Accounts receivable” in our unaudited condensed consolidated balance sheets as of September 30, 2025 and December 31, 2024, respectively. We have recorded deferred revenue of $10.4 million as of September 30, 2025 and other accrued liabilities of $5.3 million as of December 31, 2024 under this agreement. The amount as of December 31, 2024 was recorded as other accrued liabilities pending finalization of the February and August 2025 amendments mentioned above.

We also entered into a manufacturing stage transfer agreement with Zai Lab in June 2024, which was amended in September 2024 (the “Zai Manufacturing Stage Transfer Agreement”). Pursuant to this agreement, Entasis shall provide assistance to Zai Lab for building out Zai Lab's manufacturing site for XACDURO® and be compensated for Entasis' services and associated costs. We recognized license revenue under this agreement of $0.1 million and $1.0 million for the three and nine months ended September 30, 2025, respectively, and $3.4 million for the three and nine months ended September 30, 2024.

GARDP

Entasis entered into a collaboration agreement with the Global Antibiotic Research and Development Partnership (“GARDP”) for the development, manufacture and commercialization of the product candidate zoliflodacin in certain countries (“the GARDP Collaboration Agreement”). Under the terms of the GARDP Collaboration Agreement, GARDP shall use commercially reasonable endeavors to perform and fully fund the Phase 3 registrational trial, including the manufacture and supply of the product candidate containing zoliflodacin, in uncomplicated gonorrhea. We recorded $0.8 million in reimbursements from GARDP under this agreement as a reduction to research and development expense during the three and nine months ended September 30, 2025. The reimbursable amounts from GARDP for the three and nine months ended September 30, 2024 were not material.

In addition, under the GARDP Collaboration Agreement, GARDP was granted a worldwide, fully paid, exclusive and royalty-free license, with the right to sublicense, to use our zoliflodacin technology in connection with GARDP’s development, manufacture and commercialization of zoliflodacin in low-income and specified middle-income countries. We retained commercial rights in all other countries worldwide, including the major markets in North America, Europe and Asia-Pacific. We also retained the right to use and grant licenses to our zoliflodacin technology to perform our obligations under the GARDP Collaboration Agreement and for any purpose other than gonorrhea or community-acquired indications. If we believe that the results of the Phase 3 registrational trial of zoliflodacin would be supportive of an application for marketing approval, we are obligated to use our best efforts to file an application for marketing approval with the FDA within six months of the completion of the trial and to use commercially reasonable endeavors to file an application for marketing approval with the European Medicines Agency (“EMA”). Each party is responsible for using commercially reasonable efforts to obtain marketing authorizations for the product candidate in their respective territories. An application for marketing approval has been filed with the FDA in 2025.

PAION Pharma GmbH

Pursuant to the PAION AG and PAION Deutschland GmbH (together and individually “PAION”) License, La Jolla granted PAION an exclusive license to commercialize GIAPREZA® and XERAVA® in the European Economic Area, the United Kingdom and Switzerland (collectively, the “PAION Territory”). PAION is currently a subsidiary of the Humanwell Healthcare Group. We are entitled to receive potential commercial milestone payments of up to $109.5 million and double-digit tiered royalty payments. Royalties payable in a given jurisdiction under the PAION License are subject to reduction on account of generic competition and after patent expiration in that jurisdiction. Pursuant to the PAION License, PAION will be solely responsible for the future development and commercialization of GIAPREZA® and XERAVA® in the PAION Territory. PAION is required to use commercially reasonable efforts to commercialize GIAPREZA® and XERAVA® in the PAION Territory. Royalty revenue recognized under this agreement for the three and nine months ended September 30, 2025 were $0.7 million and $1.8 million, respectively. Royalty revenue recognized under this agreement for the three and nine months ended September 30, 2024 was not material.

La Jolla also entered into the PAION commercial supply agreement (the “PAION Supply Agreement”) whereby La Jolla supplies PAION a minimum quantity of GIAPREZA® and XERAVA® until the earlier of July 13, 2027, or until a new supply agreement is executed. During the term of the supply agreement, we are reimbursed for direct and certain indirect manufacturing costs at cost. We recognized $1.3 million and $2.7 million in cost reimbursements for the three and nine months ended September 30, 2025, respectively. Cost reimbursements recognized under this agreement for the three and nine months ended September 30, 2024 were not material.

Everest Medicines Limited

Pursuant to the Everest Medicines Limited (“Everest”) License, La Jolla granted Everest an exclusive license to develop and commercialize XERAVA® for the treatment of complicated intra-abdominal infections (“cIAI”) and other indications in mainland China, Taiwan, Hong Kong, Macau, South Korea, Singapore, the Malaysian Federation, the Kingdom of Thailand, the Republic of Indonesia, the Socialist Republic of Vietnam and the Republic of the Philippines (collectively, the “Everest Territory”). We are eligible to receive sales milestone payments of up to an aggregate of $20.0 million under this agreement.

We are also entitled to receive tiered royalties from Everest at percentages in the low double digits on sales, if any, in the Everest Territory of products containing eravacycline. Royalties are payable with respect to each jurisdiction in the Everest Territory until the latest to occur of: (i) the last-to-expire of specified patent rights in such jurisdiction in the Everest Territory; (ii) expiration of marketing or regulatory exclusivity in such jurisdiction in the Everest Territory; or (iii) 10 years after the first commercial sale of a product in such jurisdiction in the Everest Territory. Royalty revenue from Everest recognized for the three months ended September 30, 2025 was immaterial. We recognized $2.0 million in royalty revenue from Everest for the nine months ended September 30, 2025. Royalty revenue recognized for the three and nine months ended September 30, 2024 was $0.6 million and $2.3 million, respectively.

La Jolla also entered into the Everest commercial supply agreement (the “Everest Supply Agreement”) whereby La Jolla will supply Everest a minimum quantity of XERAVA® and will transfer to Everest certain XERAVA®-related manufacturing know-how. Under the Everest Supply Agreement, we are reimbursed for direct and certain indirect manufacturing costs at 110% of cost. Revenue recognized under the Everest Supply Agreement for the three and nine months ended September 30, 2025 was not material and $1.8 million, respectively. Revenue recognized under the Everest Supply Agreement for the three and nine months ended September 30, 2024 was $0.9 million and $2.6 million, respectively.

In-License Agreements

Basilea

In December 2024, we entered into an exclusive distribution and license agreement with Basilea, under which we were granted exclusive marketing rights to ZEVTERA® in the U.S. The agreement will remain in effect through the expiration of ZEVTERA®’s market exclusivity in the U.S. in 2034 (the “initial term”)and is subject to automatic renewal unless terminated by either party with prior notice. We paid an upfront fee of $4.0 million, which was recognized as an intangible asset and is being amortized over the initial term of the agreement. Under the agreement, we are required to exclusively purchase ZEVTERA® (in pre-packaging and labeling form) from Basilea for the duration of the term. We are also obligated to pay Basilea tiered royalties ranging from the high-teens to mid-twenties, as well as tiered milestone payments based on annual net sales in the U.S. ZEVTERA® was commercially launched in the U.S. in July 2025. Royalty expense incurred on the sales was immaterial during the three and nine months ended September 30, 2025.

George Washington University

Pursuant to the George Washington University License (the “GW License”), GW exclusively licensed to La Jolla certain intellectual property rights relating to GIAPREZA®, including the exclusive rights to certain issued patents and patent applications covering GIAPREZA®. Under the GW License, we are obligated to use commercially reasonable efforts to develop, commercialize, market and sell GIAPREZA®. We are obligated to pay a 6% royalty on net sales of GIAPREZA® and 15% on payments received from sublicensees. The obligation to pay royalties under the GW License extends through the last-to-expire patent covering GIAPREZA®. Royalty expense incurred under the GW License for the three and nine months ended September 30, 2025 were $1.1 million and $3.3 million, respectively. Royalty expense incurred for the three and nine months ended September 30, 2024 were $1.0 million and $2.5 million, respectively.

Harvard University

Pursuant to the Harvard University (“Harvard”) License, Harvard exclusively licensed to La Jolla certain intellectual property rights relating to tetracycline-based products, including XERAVA®, including the exclusive rights to certain issued patents and patent applications covering such products. Under the Harvard License, we are obligated to use commercially reasonable efforts to develop, commercialize, market and sell tetracycline-based products, including XERAVA®. For each product covered by the Harvard License, we are obligated to make certain payments for the following: (i) up to approximately $15.1 million upon the achievement of certain clinical development and regulatory milestones; (ii) a 5% royalty on direct U.S. net sales of XERAVA®; (iii) a single-digit tiered royalty on direct ex-U.S. net sales of XERAVA®, starting at a minimum royalty rate of 4.5%, with step-ups to a maximum royalty of 7.5% based on the achievement of annual net product sales thresholds; and (iv) 20% on payments received from sublicensees. The obligation to pay royalties under this agreement extends through the last-to-expire patent covering tetracycline-based products, including XERAVA®. Royalty expense incurred under the Harvard License for the three and nine months ended September 30, 2025 were $0.3 million and $1.0 million, respectively. Royalty expense incurred for the three and nine months ended September 30, 2024 were $0.3 million and $1.5 million, respectively.

Business Transfer and Subscription Agreement with AstraZeneca

Entasis entered into a Business Transfer and Subscription Agreement with AstraZeneca, AstraZeneca UK Limited and AstraZeneca Pharmaceuticals LP (collectively, “AstraZeneca”) (the “AstraZeneca Agreement”) in 2015, which was amended and restated through 2018, pursuant to which Entasis obtained, among other things, worldwide rights to durlobactam and zoliflodacin. Under the AstraZeneca Agreement, we are obligated to pay AstraZeneca a one-time milestone payment of $5.0 million within three months of achieving a specified cumulative net sales milestone for durlobactam. We are also obligated to pay AstraZeneca a one-time milestone payment of $10.0 million within two years of achieving the first commercial sale of zoliflodacin. Additionally, we are obligated to pay AstraZeneca tiered, single-digit royalties on the annual worldwide net product sales of durlobactam and, the lesser of tiered, single-digit royalties on the worldwide annual net sales of zoliflodacin and a specified share of the royalties we receive from sublicensees of zoliflodacin. Royalties on sales of zoliflodacin do not include sales by GARDP in low-income and specified middle-income countries as discussed above. Our obligation to make these royalty payments expires on a country-by-country basis for each product upon the later of (i) the 10-year anniversary of the first commercial sale of a product in that country or (ii) the expiration date of the last patent right covering the product in that country.

The royalty expense in respect of durlobactam arising from our net product sales of XACDURO® for the three and nine months ended September 30, 2025 and 2024 was not material.

Massachusetts Institute of Technology

In connection with the asset acquisition described in Note 13, “Asset Acquisition”, in September 2025, we entered into a license agreement with Massachusetts Institute of Technology (“MIT”), under which MIT licensed to us certain patent rights relating to a drug delivery device. Under this agreement, we paid an upfront fee of $0.5 million and are obligated to pay a minimal annual maintenance fee. We are also obligated to pay MIT up to $17.5 million in development, regulatory and sales milestone payments, and pay royalties in a low single-digit percentage on future net sales related to the licensed product.