Voyager Therapeutics Inc

(Former name, former address and former fiscal year, if changed since last report)

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Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

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Item 8.01. Other Events

ALS Program Update

On February 11, 2025, Voyager Therapeutics, Inc. (the “Company”)announced that it has decided to assess alternate payloads related to its superoxide dismutase 1 silencing gene therapy program for amyotrophic lateral sclerosis (the “SOD1 ALS Program”). Emerging three-month non-human primate (NHP) data suggest that an alternate payload would be necessary to achieve the Company’s desired product profile for the SOD1 ALS Program. No changes are planned to the novel capsid component of VY9323, previously the Company’s lead development candidate for the SOD1 ALS Program. Due to this decision, the Company no longer anticipates filing an investigational new drug (“IND”) application or a Canadian clinical trial application for VY9323 in mid-2025. The Company’s decision regarding the SOD1 ALS Program does not impact the Company’s other gene therapy programs; the Company continues to expect IND filings in 2025 from Neurocrine Biosciences, Inc. (“Neurocrine”) for the glucocerebrosidase 1 gene therapy program for Parkinson’s disease and other GBA1-mediated diseases, as well as the gene therapy program for Friedreich’s ataxia, pursuant to collaborations between the Company and Neurocrine. The Company also continues to expect to file an IND in 2026 for VY1706, the lead development candidate for its tau silencing gene therapy program, which has achieved desired activity levels and been well-tolerated in preclinical studies comparable to those conducted for VY9323.

Cash Runway

Based upon the Company’s current long-range operating plan, the Company estimates that its existing cash and cash equivalents and marketable securities, together with amounts expected to be received as reimbursement for development costs under its collaborations with Neurocrine and Novartis Pharma AG, and interest income, will enable the Company to fund its planned operating expenses and capital expenditure requirements into mid-2027. The Company has based these estimates on assumptions that may prove to be wrong, and the Company could use its available capital resources sooner than it currently expects.