“Our Phase 2 data confirm the potential of this vaccine to play a role in addressing this ongoing global public health crisis, as we know multiple vaccines will be needed,” Thomas Triomphe, Executive Vice President and Global Head of Sanofi Pasteur, said in a press release.
The Phase 2 study, in which 722 volunteers were given the vaccine candidate, showed a 95% to 100% efficacy rate following a second injection with “acceptable tolerability and with no safety concerns.”
After a single injection, high neutralising antibody levels were generated in participants with evidence of prior infection, which suggests the vaccine could have a strong potential for development as a booster vaccine, the companies said.
A global Phase 3, randomised, double-blind study will be initiated in the coming weeks, and is expected to enroll more than 35,000 adult participants from a broad range of countries.
The companies will also conduct booster studies with various variant formulations to assess the ability of a lower dose of the vaccine to generate a strong booster response regardless of the initial vaccine people have received.
The GSK-Sanofi coronavirus vaccine is not expected to be ready before late 2021, depending on whether the Phase 3 outcomes are positive.