Vaxart is rebounding from a difficult spring with early phase 2 data of its norovirus vaccine showing consistent immune responses and no serious side effects due to the shot.
The drip of new trial results released Thursday expanded on previous results, finding that the biotech’s oral candidate elicited immune responses at two different dose levels without any serious vaccine-related side effects. The immunogenicity spurred by the two doses far outperformed the placebo, although the company has yet to assess the vaccine’s actual efficacy. Vaxart found that the rate of adverse events was similar to placebo at both dose levels.
Vaccinated patients had higher antibody levels against the GII.4 strain of the virus than G1.1, the former of which the Centers for Disease Control and Prevention says has accounted for the majority of norovirus outbreaks since 2002. The company expects to have time point and mucosal data available in the second half of the year. But the more consequential test of the vaccine is in the company’s ongoing challenge trial, which completed recruitment last month.
The future clinical development plans remain daunting and costly. The company said in a release this is the seventh completed trial for the vaccine and that, in addition to the challenge trial, it will need to complete phase 2b and phase 3 trials. The objective of the phase 2b study is to expand on a selected dose and fortify safety data, the company explained, with the hopes of having an end-of-phase-2 meeting with the FDA in 2024.
Vaxart did not explicitly outline timing or plans for a phase 3 trial. A spokesperson for the company did not immediately respond to a request for comment on whether the company planned to pay for that trial by itself or seek a partner.
In March, the company shed 27% of its workforce after pivoting out of COVID-19 vaccine development to focus on norovirus. But the company’s cash reserves are rapidly declining, down $25.1 million in the first quarter of the year, the same as the first quarter of 2022. Vaxart reported having $71.8 million on hand at the end of March. Shares for the company were relatively stagnant in light of the new data, which remain in the Nasdaq delisting danger zone, at $0.70 per share.