Novavax has announced that it has commenced recruitment of 30,000 subjects for a placebo-controlled trial at 108 U.S. sites.  The Novavax COVID-19 vaccine candidate comprises a suspension of nanoparticles carrying the spike protein of SARS-COV-2.  This protein sub-unit vaccine is similar in principle to the Sanofi Pasteur product that has also received U.S. funding.  The Novavax vaccine incorporates saponin as an adjuvant.  Initial results from a human trial in the U.K. were “promising” although data on efficacy and safety have not been published.

Novavax is far behind both Pfizer and Moderna, both having received FDA approval with approximately 12 million doses released and 2.5 million administered by the end of December 2020. 

Recruitment of up to 30,000 volunteers for the Novavax product will be difficult given that most potential candidates would opt for vaccination with one of the two products available and scheduled for administration during the first quarter of 2021.  Participation in the trial would obviously prevent volunteers from receiving either of the available FDA-approved vaccines. In addition, half of the group that will receive the placebo will be vulnerable and those in the sub-unit vaccine group may remain in a questionable immune status.