Sanofi and Glaxosmithkline have announced a delay in their vaccine programme after it showed an insufficient immune response in trial results.
The firms said they planned to launch another study of the experimental drug next year, with plans to produce a more effective vaccine by the end of 2021.
Sanofi said the interim results of its Phase 1/2 study showed “an immune response comparable to patients who recovered from Covid-19 in adults aged 18 to 49 years, but a low immune response in older adults”. It said this was likely due to an insufficient concentration of the antigen.
The firm said it would launch a phase 2B study in February 2021 after a challenge study in non-human primates performed with an improved antigen formulation demonstrated better effects.
“We care greatly about public health which is why we are disappointed by the delay announced today, but all our decisions are and will always be driven by science and data,” Thomas Triomphe, executive VP at Sanofi said.
The Sanofi/GSK vaccine uses the same technology as one of Sanofi’s seasonal flu vaccines which is combined with a booster made by GSK.
It is a disappointing development for the firms after a number of new vaccines have been approved.
In the last week the Pfizer and Biontech vaccine has been approved and started to be rolled out in the UK. And the US regulator is now considering the same vaccine for approval.
Astrazeneca and Moderna have also reported late stage data shows the efficacy of their jabs.
Sanofi and GSK are ready to produce up to 1bn doses of their vaccine next year and have secured a number of deals including with the EU, US, Canada and the UK.
“It is… clear that multiple vaccines will be needed to contain the pandemic,” Roger Connor, president of GSK Vaccines said.