Candidates: Five vaccines based on proprietary VAAST™ Platform
Type: Oral recombinant vaccines administered by room temperature-stable tablet
Status: Vaxart said June 26 that its oral COVID-19 vaccine candidate had joined the handful of experimental vaccines being studied as part of President Donald Trump’s commitment to delivering 300 million vaccine doses protecting against SARS-CoV-2 by January 2021—while the company gears up to manufacture as many as 1 billion doses a year.
The South San Francisco, CA, vaccine developer said Friday that its room temperature stable tablet vaccine had been selected for a non-human primate (NHP) challenge study organized and funded by Operation Warp Speed. The study is designed to demonstrate the efficacy of Vaxart’s COVID-19 vaccine candidate, which is based on the company’s proprietary Vector-Adjuvant-Antigen Standardized Technology (VAAST™) Platform.
“We are very pleased to be one of the few companies selected by Operation Warp Speed, and that ours is the only oral vaccine being evaluated,” Vaxart CEO Andrei Floroiu said in a statement.
Floroiu was appointed CEO effective June 14, in part to accelerate development of the COVID-19 vaccine candidate; he retains the seat on Vaxart’s board he has held since April.
Vaxart announced its inclusion in Operation Warp speed a day after disclosing plans to ramp up manufacturing of its COVID-19 vaccine to 1 billion or more doses a year, through a Mamorandum of Understanding the company has signed with Attwill Medical Solutions Sterilflow (AMS). The agreement—whose value was not disclosed— affirmed the companies’ intent to establish AMS as a resource for lyophilization development and large scale manufacturing including tableting and enteric coating for Vaxart’s oral COVID-19 vaccine, Vaxart said.
AMS agreed to assign dedicated resources and equipment for scale-up and commercial production of the vaccine, based on finalizing a formal agreement.
In May, Vaxart said its oral vaccine candidate for COVID-19 will be manufactured by Kindred Biosciences, which agreed to provide manufacturing services from its biological development and cGMP manufacturing facility in Burlingame, CA. There, KindredBio will produce the candidate vaccine bulk drug substance under GMP, and provide it to Vaxart to be formulated into a vaccine tablet to be taken orally. KindredBio agreed to manufacture the vaccine for clinical trials beginning in the second half of 2020.
On April 30, Vaxart said it obtained positive preclinical results for its COVID-19 vaccine candidates, with “several” of the candidates generating immune responses in all tested animals after a single dose. “These preclinical results confirm that all constructs are immunogenic as measured by IgG antibodies in serum, and we observed a robust boosting effect after the second dose,” Vaxart Chief Scientific Officer Sean Tucker, PhD, stated.
Tucker said Vaxart will use the data to select a lead candidate for manufacturing: “We remain on track to start a first phase 1 study in the second half of this year.”
Earlier in April, Vaxart reported positive preclinical results for its five COVID-19 vaccine candidates, saying that several of them generated immune responses in all tested animals after a single dose. Additional data will determine which of the candidates Vaxart advances into clinical trials, Chief Scientific Officer Sean Tucker, PhD, stated, adding: “We are particularly interested in vaccine candidates that can generate mucosal immune responses in addition to serum antibody responses.”
In March, Vaxart disclosed it had produced five COVID-19 vaccine candidates for testing in preclinical models. Each vaccine construct is based on a different coronavirus antigen combination, Vaxart said, adding that it expects to advance the best performing vaccine to manufacturing for clinical trials.
Vaxart has agreed to use the “molecule-to-market” contract development and manufacturing (CDMO) services of Emergent BioSolutions in preparation for cGMP production of a vaccine. Provided Vaxart elects to proceed with cGMP manufacturing, Emergent is expected to produce bulk cGMP vaccine for use in a Phase I study that Vaxart said could be launched in the second half of 2020. Vaxart also said it was prioritizing development of the COVID-19 vaccine by putting several vaccine programs on hold, including its therapeutic HPV vaccine program and a norovirus vaccine program for which the company completed a successful Phase I study, and was actively seeking a development partner.
Emergent has said it will provide development services out of its Gaithersburg, MD location and manufacture drug substance at its Bayview facility in Baltimore, designated a Center for Innovation in Advanced Development and Manufacturing (CIADM) by the U.S. Department of Health and Human Services.
Vaxart disclosed plans in January to generate vaccine candidates based on the published genome of SARS-CoV-2, and evaluate them in preclinical models based on their ability to generate both mucosal and systemic immune responses. The company cited a study published in The Lancet Infectious Diseases, showing that the Vaxart oral H1 influenza tablet vaccine primarily protected against infection based on mucosal immunity, compared with the injectable flu vaccine that protected primarily through systemic immunity.
COVID-19: 200 Candidates and Counting
To navigate through the >200 potential therapeutic and vaccine options for COVID-19, GEN has grouped the candidates into four broad categories based on their developmental and (where applicable) clinical progress:
● FRONT RUNNER – the most promising therapeutics/vaccines based on clinical progress, favorable data or both.
● DEFINITELY MAYBE – earlier phases with promising partners, or more advanced candidates in development that have generated uneven data
● KEEPING AN EYE ON… – interesting technology, attracting notable partners, or both, but preliminary data.
● TOO SOON TO TELL – longshots pending additional experimental and/or clinical data.
GEN has also tagged the most common treatment types: