Sanofi and GSK vaccine delayed due to «low immune response» in older patients

Credit: Joel Saget/AFP

The global effort to develop vaccines against Covid-19 suffered one of its first major setbacks on Friday when Sanofi and GlaxoSmithKline announced that their jab would not be ready until late 2021, after preliminary results showed a low immune response in older people.

The vaccine from Sanofi of France and GSK of the UK is based on existing flu-vaccine technology and would face less severe logistical challenges than that created by Pfizer and BioNTech which has been approved in several countries.

It can be stored at standard fridge temperatures of between 2 and 8 degrees Celsius, whereas the Pfizer vaccine must be stored at between -70 and -80 degrees Celsius.

The two companies had received a large number of pre-emptive orders for their jab, including one of 60 million doses from the United Kingdom.

Sanofi and GSK said early test results 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."

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

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

"There is no question of abandoning the vaccine," he told AFP.