13. INCOME TAXES

The domestic and foreign components of income (loss) before income tax provision (benefit) were as follows:

Year ended December 31,

2025

2024

United States

$

(105,042,346)

$

(40,465,586)

Foreign

 

 

Total

$

(105,042,346)

$

(40,465,586)

The federal and state income tax provision (benefit) is summarized as follows:

Year ended December 31,

2025

2024

Current

  ​ ​ ​

Federal

$

$

State and local

1,600

1,600

Total current tax expense

1,600

1,600

Deferred

Federal

State and local

Total deferred tax expense

Total

Federal

State and local

1,600

1,600

Total tax expense

$

1,600

$

1,600

Deferred income taxes reflect the net tax effects of (a) temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes, and (b) operating losses and tax credit carryforwards.

The tax effects of significant items comprising the Company’s deferred taxes as of December 31 are as follows:

Year ended December 31,

2025

2024

Deferred tax assets:

  ​ ​ ​

Accrued expenses

$

1,061,030

$

722,851

Stock-based compensation

5,236,924

5,088,808

Research and development expense

11,592,478

15,993,708

Lease liabilities

3,052,803

406,366

Net operating losses

54,428,383

32,472,461

Credits

28,848,564

22,314,502

Deferred revenue

2,522,497

3,360,445

CIRM liability

640,236

Total deferred tax assets

107,382,915

80,359,141

Deferred tax liabilities:

Lease right-of-use assets

(2,845,759)

(367,555)

Fixed assets

(1,091,120)

(1,357,352)

Other comprehensive income

(59,521)

(66,036)

Total deferred tax liabilities

(3,996,400)

(1,790,943)

Valuation allowance

(103,386,515)

(78,568,198)

Net deferred taxes

$

$

ASC 740 requires that the tax benefit of net operating losses, temporary differences and credit carryforwards be recorded as an asset to the extent that management assesses that realization is more likely than not. Realization of the future tax benefits is dependent on the Company's ability to generate sufficient taxable income within the carryforward period. Because of the Company's recent history of operating losses, management believes that recognition of the deferred tax assets is currently not likely to be realized and, accordingly, has provided a valuation allowance.

The valuation allowance increased by approximately $24.8 million during 2025 and approximately $12.1 million during 2024.

Net operating losses and tax credit carryforwards as of the December 31, 2025 are as follows:

Amount

Expiration Years

Net operating losses, federal (post December 31, 2017)

$

160,690,929

Do Not Expire

Net operating losses, federal (prior to January 1, 2018)

$

39,383,370

2031

Net operating losses, state

$

177,927,620

2028

Tax credits, federal

$

27,054,520

2027

Tax credits, state

$

2,270,942

Indefinite

The effective tax rate of the Company's provision (benefit) for income taxes differs from the federal statutory rate as follows:

Year ended December 31,

2025

2024

Amount

Rate

Amount

Rate

U.S. federal statutory tax rate

$

(22,058,893)

21.0%

$

(8,497,773)

21.0%

State and local income taxes, net of federal income tax effect (1)

1,264

0.0%

1,264

0.0%

Tax credits

Orphan drug tax credit

(4,778,164)

4.6%

(4,778,164)

11.8%

Research and development tax credit

(399,695)

0.4%

(399,695)

1.0%

Change in valuation allowance

26,851,125

-25.6%

13,042,758

-32.2%

Nondeductible items

Stock-based compensation, including windfalls/shortfalls

314,710

-0.3%

612,474

-1.5%

Other

71,253

-0.1%

20,736

-0.1%

Effective income tax rate

$

1,600

0.0%

$

1,600

0.0%

(1)The majority of taxes in the state and local income taxes category is reported in California.

The cash paid for income taxes (net of refunds) was $1,600 for both 2025 and 2024 and applied only to state of California.

The tax years 2023 through 2025 remain open to examination by the Internal Revenue Service and certain state tax authorities, although net operating loss and tax credit carryforwards generated prior to 2007 may still be adjusted upon examination by the Internal Revenue Service or state tax authorities if they have or will be used in a future period.

Under Section 382 of the Code, the Company’s ability to utilize NOL carryforwards or other tax attributes, such as federal tax credits, in any taxable year may be limited if the Company has experienced an “ownership change.” Generally, a Section 382 ownership change occurs if one or more stockholders or groups of stockholders who owns at least 5% of a corporation’s stock increases its ownership by more than 50 percentage points over its lowest ownership percentage within a specified testing period. Similar rules may apply under state tax laws. We have experienced an ownership change that we believe under Section 382 of the Code will result in limitation in our ability to utilize net operating losses and credits. In addition, the Company may experience future ownership changes as a result of future offerings or other changes in ownership of its stock. As a result, the amount of the NOLs and tax credit carryforward presented in the financial statement could be limited and may expire unutilized. The Company’s net operating loss carryforwards are subject to Internal Revenue Service (“IRS”) examination until they are fully utilized and such tax years are closed.

The Company’s policy is to include interest and penalties related to unrecognized tax benefits in income tax expense. Interest and penalties were insignificant for the years ended December 31, 2025 and 2024.

About Income Taxes Disclosures

The income tax disclosure reveals how much a company actually pays in taxes versus what the statutory rate would predict. Analysts focus on the effective tax rate (ETR) reconciliation, which breaks down every item driving the gap between the 21% federal rate and the company's reported ETR — including R&D credits, foreign rate differentials, and state taxes. Deferred tax assets (DTAs) and their valuation allowances signal management's confidence in future profitability: a rising allowance suggests the company doubts it can use accumulated tax benefits. Uncertain tax benefit (UTB) reserves quantify exposure to IRS challenges on aggressive positions.

Key signals to watch: sudden ETR drops without clear operational reasons, large increases in valuation allowances, growing UTB balances, and significant unremitted foreign earnings. Post-TCJA, pay attention to GILTI and BEAT provisions that affect multinational tax structures. Compare the cash taxes paid (from the cash flow statement) against the income tax provision to gauge earnings quality.