The stop order came on Aug. 5, the same day Health Secretary Robert F. Kennedy Jr. terminated 22 mRNA vaccine projects under the Biomedical Advanced Research and Development Authority, though Vaxart’s candidate is protein-based.
The Department of Health and Human Services has slapped vaccine manufacturer Vaxart with another stop order for its next-generation oral COVID-19 vaccine, which the California-based company was developing with support from the federal government.
According to an SEC document on Aug. 5, Vaxart was told to stop screening and enrolling patients into a Phase IIb trial for VXA-CoV2-3.3, an investigational pill designed to elicit broad protection against variants of the SARS-CoV-2 virus. Vaxart can “continue efforts associated with the per protocol follow-up for the 10,000-person cohort, to the extent already dosed,” as per the regulatory filing. The biotech has so far enrolled around half of its target participants.
HHS did not give Vaxart a reason for the order, only indicating that it will release a “follow-up notice with further details,” according to the SEC document. Vaxart is working on the mid-stage trial with funding from the Biomedical Advanced Research and Development Authority (BARDA), which gave the biotech an award of up to $460 million.
VXA-CoV2-3.3 is an orally available S-protein COVID-19 vaccine that, according to the biotech’s website, is designed to elicit durable immunity against the virus. Preclinical data additionally showed that the immunizing pill can also lower airborne transmission by minimizing viral shedding.
In its mid-stage study, Vaxart aims to compare VXA-CoV2-3.3 with Pfizer and BioNTech’s mRNA-based vaccine Comirnaty across more than 10,000 patients. The company started dosing in May and expects the trial to wrap up in November 2026. The program has had a rough couple of months, however, with HHS in February issuing a similar stop order to review its initial findings. The freeze was lifted in April.
Beyond Vaxart, Health Secretary Robert F. Kennedy Jr. has enacted many other policy changes that are in line with his well-documented history of vaccine criticism. Most recently, Kennedy canceled some $500 million—corresponding to 22 projects—in BARDA contracts for mRNA vaccines. Incidentally, this move came on Aug. 5, the same day the new stop work order for Vaxart’s protein-based vaccine was handed out.
Kennedy in late July also said that he would “fix” the U.S. Vaccine Injury Compensation Program, claiming that the system has “devolved into a morass of inefficiency, favoritism, and outright corruption.” It is unclear what exact changes he is considering. In May, Kennedy also removed routine COVID-19 vaccination from the CDC’s guidelines for healthy children and healthy pregnant women—a move that a coalition of medical societies blasted in July as a “baseless and uninformed policy decision.”
