XML 49 R31.htm IDEA: XBRL DOCUMENT
v3.24.0.1

Income Taxes (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2023
Income Taxes |
Schedule of reconciliation of the income tax benefit at the federal statutory tax rate to effective income tax rate | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | As of |
​ | ​ | December 31, |
​ |  | 2023 |  | 2022 |  | 2021 |
Statutory tax rate |  | 21.00 | % | 21.00 | % | 21.00 | %
State tax, net of federal benefit |  | 10.24 | ​ | 9.83 | ​ | 7.45 | ​
Research and development credit |  | 0.65 | ​ | 0.78 | ​ | 2.94 | ​
Orphan drug credit |  | 3.37 | ​ | 2.15 | ​ | 7.58 | ​
Stock compensation |  | (1.37) | ​ | (0.29) | ​ | (1.05) | ​
Other |  | (0.48) | ​ | (0.04) | ​ | (0.47) | ​
Rate changes | ​ | (6.52) | ​ | — | ​ | ​ | ​
Change in valuation allowance |  | (27.10) | ​ | (33.44) | ​ | (37.45) | ​
Effective tax rate |  | (0.21) | % | — | % | — | %
Schedule of principal components of deferred tax assets | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | As of
​ | ​ | December 31,
​ |  | 2023 |  | 2022
Deferred tax assets: |  | ​ |  |  | ​ |
Net operating loss carryforwards | ​ | $ | 153,685 | ​ | $ | 135,470
Research and development credits | ​ |  | 16,139 | ​ |  | 14,380
Orphan drug credit | ​ |  | 25,484 | ​ |  | 19,281
Capitalized license fee | ​ |  | 2,311 | ​ |  | 2,776
Stock-based compensation | ​ | ​ | 13,159 | ​ | ​ | 11,074
Section 174 Costs | ​ | ​ | 50,688 | ​ | ​ | 29,663
Deferred revenue | ​ | ​ | 350 | ​ | ​ | 438
Accrued Expenses & Other | ​ |  | 5,680 | ​ |  | 4,536
Total deferred tax assets | ​ |  | 267,496 | ​ |  | 217,618
Valuation allowance | ​ | ​ | (267,158) | ​ | ​ | (217,257)
Net deferred tax assets | ​ | ​ | 338 | ​ | ​ | 361
Deferred tax liabilities: | ​ | ​ | ​ | ​ | ​ | ​
Operating lease right-of-use asset and other | ​ | ​ | (338) | ​ | ​ | (361)
Total deferred tax liabilities | ​ | $ | (338) | ​ | $ | (361)

X
- References No definition available. + Details
Name: | us-gaap_IncomeTaxDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the components of net deferred tax asset or liability recognized in an entity's statement of financial position, including the following: the total of all deferred tax liabilities, the total of all deferred tax assets, the total valuation allowance recognized for deferred tax assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Paragraph 2 -Section 50 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482685/740-10-50-2 + Details
Name: | us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the reconciliation using percentage or dollar amounts of the reported amount of income tax expense attributable to continuing operations for the year to the amount of income tax expense that would result from applying domestic federal statutory tax rates to pretax income from continuing operations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Paragraph 12 -Section 50 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482685/740-10-50-12 + Details
Name: | us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration