Following the announcement that Novavax has agreed a $167m deal to acquire Praha Vaccines to aid its manufacturing capabilities for its Phase I COVID-19 vaccine candidate;

Reynald Castañeda, Pharma Writer for the Investigative News team at GlobalData, offers his view:

“Novavax may be at a disadvantage compared to Clover Biopharmaceuticals, which also has a protein COVID-19 vaccine in development. There are at least 60 protein subunit vaccines being explored between the discovery and Phase I stage, according to the GlobalData Pharma Intelligence Center, including Novavax’s NVX‑CoV2373 and Clover’s S-Trimer, which are both protein subunit vaccines. IMV also has such a vaccine ready to enter clinical trials.

“Despite the market reactions to these three companies’ announcements, it is still premature to predict a clear frontrunner among the three vaccines due to information gaps such as how the spike protein antigen is constructed and reproduction platforms to be used for manufacturing.

“On Monday 25 May, Novavax’s stock jumped as high as 17% during trading hours on announcing it had enrolled the first participants in its Phase I/II trial. IMV’s stock rose 20% on 21 May after announcing plans to move DPX-COVID-19 into clinical development. Dynavax Technologies, which is supplying the adjuvant for Clover’s candidate, was up 14% on 24 March upon its collaboration announcement. Considering Clover will use Dynavax’s adjuvant, which is already FDA-approved, it could potentially have the upper hand versus Novavax and IMV. Interviewed experts explained that Novavax’s adjuvant type may have limitations and IMV is not coupling its vaccine with an adjuvant.

“In fact, IMV’s vaccine drew the least expert enthusiasm. Novavax has the leg up – as NVX‑CoV2373 uses a recombinant spike protein antigen compared to Clover’s native-like vaccine; i.e., resembling the native SARS-CoV-2 spike protein. IMV’s vaccine does not feature the entire spike protein but instead includes 23 SARS-CoV-2 peptide epitopes, and peptides by themselves are not immunogenic, experts explained.

“Yet, experts also said that IMV may have an advantage in terms of manufacturing, since its vaccine only features viral peptides. While Novavax hasn’t announced its production process, Clover’s vaccine may be at a disadvantage, as its spike protein antigen is produced via a mammalian cell-culture based expression system, which is an expensive process. Novavax’s announcement today noted that the acquired facility would provide annual capacity of over one billion doses of antigen in 2021 for NVX‑CoV2373.

“The vaccine development story, though, has many twists and turns. Prior reporting focused on one of the perceived frontrunners – Moderna’s mRNA vaccine mRNA-1273 – noted that while it has a number of pros, there are also many long-term success obstacles ahead. Its future Phase II immunogenicity data may not forecast Phase III protection results, and a field trial for approval is likely to require around 25,000 volunteers. A human challenge trial could be considered for quick protection data, but such a trial design also has its own operational and ethical conundrums.

“Novavax’s Australia-based Phase I will recruit about 130 patients, and preliminary immunogenicity and safety data is expected in July. Clover’s Phase I will also be based in Australia but has not yet been scheduled, while IMV’s Phase I is slated to start in the summer. Moderna’s Phase II is expected to start imminently.”