Pharmaceutical companies Sanofi and GSK have announced that they are pushing back the expected availability date of their Covid-19 vaccine until the end of 2021, due to a low immune response in elderly people.
Issuing a joint statement following their phase 1 and 2 interim results, they said they would need to conduct a phase 2b study with an improved antigen formulation, after their vaccine candidate showed an insufficient response rate in older adults.
Executive Vice President of Sanofi Pasteur Thomas Triomphe explained: “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.”
In July 2020, the US chose to accelerate the development and manufacturing of Sanofi and GSK’s drug. Further work on the drug will take place in February 2021, supported by America’s Operation Warp Speed, with the two companies hoping to include a proposed comparison with an authorized Covid-19 vaccine.
They did not initially provide a specific date by which they hope the vaccine will be available to the public, but stated that it is expected to be in the last quarter of 2021.
The news is the second blow to the fight against Covid-19 in one day, after a promising Australian vaccine candidate was abandoned after trial participants returned false-positive HIV results.
The jab, being developed by CSL and the University of Queensland, had shown effectiveness in making antibodies during phase-one trials, but, due to the flaw and the time it would take to address it, the two sides decided it would not be realistic to continue development.