A COVID-19 vaccine from drugmakers Sanofi and GlaxoSmithKline produced antibody responses on par with those who experienced natural infection, the companies said in early clinical results, paving the way for a late-stage trial in the coming weeks.
The companies said the recombinant DNA vaccine exhibited no safety problems in a randomized, double-blind study involving more than 700 people ages 18 and older in the U.S. and Honduras.
Participants showed robust antibody levels after two doses, with higher levels observed in those ages 18 to 59.
People who were previously infected by the coronavirus produced high levels after a single injection, giving the companies hope that their vaccine could serve as an effective booster.
The drugmakers plan to enroll more than 35,000 adults in multiple countries to test the shots against the original strain and the variant first detected in South Africa.
Several COVID-19 vaccines are circulating now, though scientists say it is good to employ multiple options to bolster supply and have a range of vaccine to grapple with the virus.
Sanofi’s recombinant technology inserts genetic information for the coronavirus directly into insect cells, so they can grow proteins that match features of the virus’s trademark spike and teach the body to attack it.
GlaxoSmithKline is supplying what’s known as an adjuvant, an ingredient that boosts the immune response to the information from the protein vector.
Their platform does not require a deep-freeze cold chain like the messenger-RNA shots from Pfizer-BioNTech and Moderna, which consist of a snippet of genetic code that’s encapsulated in lipids and instructs the body to make impostors of the coronavirus’s spike protein, so the body knows how to fight the real thing.
“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 companies, which received U.S. government funding to support their efforts, said they will test formulations of the vaccine against specific variants to see if it could serve as an effective booster shot — regardless of the initial vaccine someone has received.
The drugmakers hope to seek regulatory approval by the final quarter of this year.