3.        Acquisitions

Sangamo Asset Acquisition

On August 25, 2026, the Company entered into an Asset Purchase Agreement with Sangamo (the “Sangamo Purchase Agreement”) to acquire from Sangamo, subject to the terms and conditions set forth in the Sangamo Purchase Agreement, all of Sangamo’s right, title and interest in and to the assets primarily related to ST-920, a one-time administered AAV gene therapy product candidate for Fabry disease, which Sangamo had been developing and investigating in clinical trials (the “Sangamo Asset Acquisition”).

Upon the closing of the Sangamo Asset Acquisition on September 17, 2026 and pursuant to the Sangamo Purchase Agreement, the Company paid upfront cash consideration of $111.0 million and may become obligated to make up to an additional $100.0 million in contingent milestone payments upon the achievement of specified regulatory approval milestones.

As ST-920 was the only asset acquired and no liabilities were assumed, the Company determined that all of the fair value was concentrated in ST-920 and accounted for the transaction as an asset acquisition under ASC 805-50. As ST-920 is an in-process research and development asset, the Company concluded that it did not have any alternative future use, and accordingly, the upfront cash consideration of $111.0 million was recorded to acquired in-process research and development within operating expenses on the Company’s statement of operations during the three and nine months ended September 30, 2026. The contingent milestone payments were not included in the initial cost of the acquired assets and

will be capitalized and amortized over their expected useful lives when the related contingencies are resolved and the amounts become payable.