The study is a randomized, double-blind, and placebo-controlled trial designed to evaluate the safety, tolerability, and immunogenicity of the candidate. A total of 440 healthy adults are being enrolled in the trial across 11 sites in the U.S.

The companies anticipate results as early as December, which will support the initiation of a phase III trial expected to begin in December as well. With sufficient data, the companies plan to request regulatory approval in the first half of 2021.

Preclinical data showed that the vaccine candidate produced high levels of neutralizing antibodies after two injections of the adjuvanted recombinant vaccine that was comparable to levels in humans who recovered from COVID-19. Plans to publish the preclinical results are in the works for later in the year.

Sanofi is leading the clinical development and registration of the COVID-19 vaccine. In parallel, both companies are scaling up manufacturing of the antigen and adjuvant with the goal of producing one billion doses in 2021.

The development of the vaccine candidate is being supported through funding and collaboration with the Biomedical Advanced Research and Development Authority, a U.S. federal agency.