After their COVID-19 vaccine candidate failed to induce a strong enough immune response in people 50 years and older in the interim results, Sanofi and GlaxoSmithKline Plc have said that the vaccine will only be ready until the end of next year, news agency AFP reported.

In a statement, the companies said that the vaccine's potential availability had been pushed back "from mid-2021 to Q4 2021”.

Their adjuvanted recombinant protein-based COVID-19 vaccine programme is based on technology that Sanofi has used to produce seasonal influenza vaccines and on immunological agents developed by GSK, the AFP report said.

The statement quoted a recent study in non-human primates "performed with an improved antigen formulation demonstrated that the vaccine candidate could protect against lung pathology and lead to rapid viral clearance from the nasal passages and lungs, within 2 to 4 days.”

Thomas Triomphe, Executive Vice President and Head of Sanofi Pasteur said, "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.”

"We have identified the path forward and remain confident and committed to bringing a safe and efficacious COVID-19 vaccine," he said.

A phase two trial is expected to begin in February 2021, followed by a phase 3 study if the results are promising.

The AFP report quoted Roger Connor, President of GSK Vaccines, who said "The results of the study are not as we hoped. Based on previous experience and other collaborations, we are confident that GSK's pandemic adjuvant system, when coupled with a COVID-19 antigen, can elicit a robust immune response."

(With inputs from AFP)