7. Lease obligation

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Operating Leases

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As of December 31, 2025, the Company has a lease for laboratory and office space at 75 Hayden Avenue in Lexington, Massachusetts through January 31, 2031, and a lease for additional office and laboratory space at 64 Sidney Street in Cambridge, Massachusetts (the “Cambridge Facility”) through November 30, 2026.

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In August 2023, the Company entered into a first amendment (the “First Amendment”) to its existing lease for laboratory and office space at 75 Hayden Avenue in Lexington, Massachusetts, pursuant to which the Company agreed to lease approximately 61,307 square feet of additional office and laboratory space. The commencement date for the First Amendment occurred on February 1, 2024. The expected contractual obligation under the First Amendment to the Company’s existing lease is approximately $35.4 million, to be paid over the 7-year term of the lease.

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The Company’s lease agreements require the Company to maintain a cash deposit or irrevocable letter of credit in the aggregate amount of $2.7 million payable to its landlords as security for the performance of its obligations under the leases. These amounts are recorded as restricted cash in the accompanying consolidated balance sheets.

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In June 2024, the Company vacated its leased office and laboratory space in Cambridge, Massachusetts. The Company recorded an impairment charge of $2.8 million to operating expenses during the second quarter of 2024 as a result of the carrying value of the leased office and laboratory space asset group exceeding the undiscounted cash flows projected from a planned sublease of the facility. The impairment charge reduced the carrying value of the leased office and laboratory space asset group by $2.8 million. In August 2024, the Company executed the sublease of the Cambridge Facility (the “Sublease Agreement”). Payments received under the Sublease Agreement are included in other income in the consolidated statements of operations and comprehensive (loss) income.

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Total lease cost for operating leases of approximately $7.5 million, $10.0 million, and $3.6 million was incurred during the years ended December 31, 2025, 2024, and 2023, respectively. This includes $2.8 million in impairment charges recognized during the year ended December 31, 2024. As of December 31, 2025, the weighted average remaining lease term was 3.7 years, and the weighted average incremental borrowing rate used to determine the operating lease liability was 6.5%. As of December 31, 2024, the weighted average remaining lease term was 4.7 years, and the weighted average incremental borrowing rate used to determine the operating lease liability was 6.8%.

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The following table summarizes the operating sublease income generated under the Sublease Agreement for the years ended December 31, 2025, 2024, and 2023:

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Future minimum lease payments due under operating leases are as follows:

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