The investigational COVID-19 vaccine uses the same recombinant protein-based technology as one of Sanofi’s seasonal flu vaccines, along with GSK’s established pandemic adjuvant technology.
The drug companies had hoped to have regulatory approval for their jab in the first half of this year, but interim results from a Phase 1/2 study, released in December 2020, had shown an “insufficient” response in the over-50s, the age group deemed at higher risk for contracting the severe form of the virus.
The interim results from the phase 2 trial on the vaccine, published today, on the contrary, showed a “strong neutralizing antibody response” in all adult age groups, and raised no safety concerns, triggering a move to next stage, phase 3.
The companies also noted a high immune response after a single dose of the shot in patients with prior infection, indicating, they said, strong booster potential for the jab.
“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, especially as variants continue to emerge and the need for effective and booster vaccines, which can be stored at normal temperatures, increases,” said Thomas Triomphe, executive vice president and global head of Sanofi Pasteur.
The Phase 3 study on the vaccine is expected to start in the coming weeks. That trial is set to enroll more than 35,000 adult participants from a broad range of countries and will assess the efficacy of two vaccine formulations against variants that first emerged in Wuhan (D614) and South Africa (B.1.351).