Vaxart Announces Last Subject Dosed in Phase 2 Trial of its Bivalent Norovirus Candidate, and All Subjects Challenged in Phase 2 Challenge Study of Monovalent Norovirus Candidate

No Vaccine Related Serious Adverse Events (SAEs) reported to date

On track to report topline data from two Phase 2 norovirus vaccine studies over the next 3 months

SOUTH SAN FRANCISCO, Calif., June 06, 2023 (GLOBE NEWSWIRE) -- Vaxart, Inc. (Nasdaq: VXRT) today announced that the last subject has completed dosing in the Phase 2 clinical trial of its oral pill bivalent norovirus vaccine candidate. In addition, all patients have been challenged in its challenge study of its G.1.1 monovalent vaccine candidate. No vaccine related SAEs have been reported to date in either trial, consistent with the safety profile observed in all our norovirus trials.

“We look forward to announcing key topline data of both Phase 2 trials for our norovirus candidates in the coming months as we continue to make timely progress in these studies," said Dr. James F. Cummings, Vaxart’s Chief Medical Officer. “Both trials now are fully enrolled, and all subjects have been dosed and no vaccine-related SAEs reported in either study. Data from these Phase 2 trials will inform the next steps for our clinical development strategy for these potentially promising vaccine candidates.”

Vaxart continues to expect to report topline data from the ongoing Phase 2 dose-ranging study (NCT05626803) of its bivalent norovirus vaccine candidate in mid-2023. The primary endpoints are safety and immunogenicity, with the objective of determining dose levels for Phase 3 development.

The Company also expects to report topline data from the ongoing Phase 2 challenge study (NCT05212168) of Vaxart’s G1.1 monovalent norovirus vaccine candidate during Q3 2023. Primary endpoints include safety and reduction in acute gastroenteritis (AGE) caused by norovirus infection, while additional endpoints include reduction in AGE severity, reduction in shedding, and immunogenicity, with the objective of determining efficacy against norovirus G1.1-induced AGE.

Norovirus is the leading cause of acute viral gastroenteritis in all age groups in the U.S. However, there are no approved vaccines for noroviruses. In the U.S. alone, the annual disease burden from norovirus is $10.5 billion, as on average norovirus causes 19 to 21 million cases of AGE, infects 15% of all children under the age of 5, and leads to 465,000 emergency department visits, 109,000 hospitalizations, and 900 deaths.