Sanofi and GSK initiate Phase I/II trial of COVID-19 vaccine candidate

The trial will evaluate the safety, tolerability and immunogenicity of the duo’s COVID-19 recombinant protein-based vaccine candidate in 440 healthy US participants.

doctor wearing face mask holding a vial labelled 'COVID-19 Vaccine'

Sanofi and GlaxoSmithKline (GSK) have initiated the Phase I/II clinical trial for their COVID-19 vaccine. The vaccine candidate, developed by the partnership, incorporates the same recombinant protein-based technology as one of Sanofi’s seasonal influenza vaccines and GSK’s pandemic adjuvant technology.

The trial is a randomised, double blind and placebo-controlled trial designed to evaluate the safety, tolerability (reactogenicity) and immunogenicity of the COVID-19 vaccine. It is expected 440 healthy adults will be enrolled in the trial across 11 investigational sites in the US.

Initial results are expected in early December 2020, which the companies hope will support the initiation of a Phase III trial in the same month. If the data are sufficient for licensure application, the enterprises plan to request regulatory approval in the first half of 2021.

In preclinical studies the vaccine candidate showed an acceptable reactogenicity profile and high levels of SARS-CoV-2 neutralising antibodies after two injections, comparable to levels in humans who recovered from the COVID-19 infection. In parallel, the companies are scaling up manufacturing of the antigen and adjuvant with the target of producing up to one billion doses in 2021.

Roger Connor, President of GSK Vaccines said, “Moving this vaccine candidate into clinical development is an important moment in the progress towards addressing the global pandemic we are all facing. This builds on the confidence shown by governments already in the potential of this protein-based adjuvanted vaccine candidate, which utilises established technology from both companies and can be produced at scale by two of the leading vaccine manufacturers globally. We now look forward to the data from the study, and if positive, beginning Phase III [trials] by the end of the year.”

The development of the adjuvanted COVID-19 vaccine candidate is being supported with funding from the US Biomedical Advanced Research and Development Authority (BARDA).

The companies also highlighted that they are committed to making the vaccine available globally. They have already agreed to supply up to 100 million doses of their COVID-19 recombinant protein-based vaccine to the US government, who has a further option to discuss the purchase of up to 500 million doses longer term. They have also agreed to supply up to 60 million doses of the vaccine to the UK government and up to 300 million doses to the European Union.

The partners also intend to supply a significant portion of total worldwide available supply in 2021/2022 to COVAX, the vaccines pillar of the ACT (Access to COVID‐19 Tools)-Accelerator, a global collaboration of leaders of governments, global health organisations, businesses and philanthropies to accelerate development, production and equitable access to COVID-19 tests, treatments and vaccines.