The Perfect Enemy | Scoop: COVID vaccine pill maker posts positive Phase 2 results
July 10, 2025
Scoop: COVID vaccine pill maker posts positive Phase 2 results
Scoop: COVID vaccine pill maker posts positive Phase 2 results

San Francisco-based biotech Vaxart, an underdog in the COVID response that’s developing a vaccine that would be delivered in a pill, is reporting promising Phase 2 clinical trial data today, the company told Axios exclusively.

Why it matters: The two-dose vaccine candidate was “safe and well-tolerated” and produced immune responses against the wild strain of the virus, as well as subsequent strains including Omicron, officials said.

  • It also showed what’s called a mucosal antibody response which can provide an added layer of protection and help reduce viral transmission, they said.
  • “We believe that the positive findings for multiple immunologic responses may ultimately translate to enhanced protection against infection with, and/or transmission of, SARS-CoV-2,” said Sean Tucker, Vaxart’s founder and chief scientific officer.

Be smart: As the first part of a Phase 2 study, this is still a relatively small study. It was based on 66 people.

  • But it’s an important milestone as the first time an oral COVID vaccine has concluded a Phase 2 trial, they said.
  • They say the pill could be ultimately “groundbreaking” for the global delivery of COVID vaccines and help get ahead of new COVID variants.

By the numbers: The trial measured for immunogenicity, neutralizing antibodies, and mucosal responses, in addition to safety.

  • They found COVID-19-specific serum neutralizing antibodies increased between 1.2- and 2-fold, with higher increases for higher vaccine doses.
  • Among 18-to-55-year-old subjects previously vaccinated with mRNA vaccines, they found COVID-19-specific antibody levels in the blood increased 1.6-fold.
  • About half of the participants, as well as half of the subjects that previously received an mRNA vaccine, had at least a 1.5-fold increase in mucosal antibodies.

Yes, but: The response by immune cells known as T cells was not as strong as they previously observed with their other COVID-19 vaccine candidate. 

What to watch: The company is working on new Omicron-based vaccine candidates to evaluate in preclinical models this year and to advance to clinical trials in the first half of 2023.

  • The company is planning more studies in 2023, including larger trials in the U.S. and internationally.