On December 4, 2024, HilleVax, Inc. (the "Company") commenced a workforce reduction of 28 employees, constituting approximately 70% of the Company's workforce, to reduce its operating expenses. The Company's remaining management and employees will continue to explore and evaluate the development of its norovirus vaccine candidates as well as business development-related activities for these vaccine candidates and other strategic alternatives. This workforce reduction is expected to be substantially complete by the end of January 2025.

The Company currently estimates that it will incur charges associated with the workforce reduction of approximately $6.1 million primarily related to employee severance payments, benefits and related termination costs. The Company expects the majority of related charges to be recognized in the fourth quarter of 2024.

The estimates of the charges and expenditures that the Company expects to incur in connection with the workforce reduction, and the timing thereof, are subject to several assumptions and the actual amounts incurred may differ materially from these estimates. In addition, the Company may incur other charges or cash expenditures not currently contemplated due to unanticipated events that may occur, including in connection with the implementation of the workforce reduction.