14. Income taxes

The provision for incomes taxes is as follows:

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A reconciliation of the expected income tax provision computed using the federal statutory income tax rate at the Company’s effective tax rate is as follows:

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(1) State taxes in Massachusetts comprise the majority of the tax effect in this category.

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The Company has historically incurred net operating losses (“NOLs”). As of December 31, 2025, the Company had federal and state net operating loss carryforwards of $249.4 million and $236.4 million, respectively. The year-over-year increase in NOLs is primarily driven by provisions of the “One Big Beautiful Bill Act” which the Company availed itself of as discussed further below. The state NOLs will expire beginning in 2041 while the federal NOLs do not expire. As of December 31, 2025, the Company had federal and state research and development tax credit carryforwards of $29.2 million and $18.0 million, respectively, which expire beginning in 2030. As of December 31, 2025, the Company has $0.2 million of state investment credits, which expire beginning in 2026.

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The significant components of the Company’s deferred tax assets and (liabilities) are as follows:

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Management has evaluated the positive and negative evidence bearing upon the realizability of the Company’s deferred tax assets, which principally comprise NOL carryforwards, tax credit carryforwards, and capitalized research expenses. Management has determined that it is more likely than not that the Company will not recognize the benefits of its federal and state deferred tax assets, and as a result, a valuation allowance of $145.4 million and $105.9 million has been established at December 31, 2025 and 2024, respectively. The valuation allowance increased by $39.6 million for the year ended December 31, 2025. The primary reason for the difference between the income tax provision recorded by the Company and the amount of income tax provision at statutory income tax rates was the change in the valuation allowance.

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As of December 31, 2025 and 2024, the Company had no unrecognized tax benefits.

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Cash paid for income taxes, net of refunds consists of the following:

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Sections 382 and 383 of the U.S. Internal Revenue Code (“IRC”) impose substantial restrictions on the utilization of net operating losses and other tax attributes in the event of a cumulative “ownership change”. In general, a company would undergo an ownership change if its “5-percent shareholders” (determined under Section 382) increased their collective ownership of the company’s stock by more than 50% over a rolling three-year period. Accordingly, if the Company generates taxable income in the future, changes in stock ownership, including equity offerings and share repurchase programs, as well as other changes that may be outside its control, could potentially result in material limitations on the Company’s ability to use its net operating loss and research tax credit carryforwards. Similar rules may apply under state tax laws. The Company has completed an analysis of IRC Section 382 through December 31, 2023, and the amounts reflected in the tax footnote are net of any limitations on the net operating losses and credits as a result

of this analysis. The Company may have experienced ownership changes in the past, and it may experience ownership changes in the future, some of which are outside of its control. This could limit the amount of net operating losses and research tax credits that the Company can utilize annually to offset future taxable income or tax liabilities. Subsequent statutory or regulatory changes in respect to the utilization of net operating losses and research tax credits for federal or state purposes, such as suspensions or limitations on the use of net operating losses and research tax credits carried forward, or other unforeseen reasons, may result in the Company’s existing net operating losses and research tax credits expiring or otherwise being unavailable to offset future income tax liabilities.

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Interest and penalty charges, if any, related to unrecognized tax benefits would be classified as income tax expense in the accompanying statements of operations. As of December 31, 2025, and 2024, the Company has no accrued interest related to uncertain tax positions. Since the Company is in a loss carryforward position, it is generally subject to examination by the U.S. federal, state, and local income tax authorities for all tax years in which a loss carryforward is available.

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On July 4, 2025, President Donald Trump signed the “One Big Beautiful Bill Act” into law, which is considered the enactment date under U.S. GAAP. Key corporate tax provisions include the restoration of 100% bonus depreciation, immediate expensing for domestic research and experimental expenditures, changes to Section 163(j) interest limitations, updates to GILTI and FDII rules, amendments to energy credits, and expanded Section 162(m) aggregation requirements. In accordance with ASC 740, the Company recognized the effects of the new tax law in the period that includes the enactment date.