In February, Sanofi signed on with the US emergency preparedness agency Biomedical Advanced Research and Development Authority (BARDA) to develop a recombinant protein-based technology that was used to produce its Flublok influenza vaccine as a possible vaccine for Covid-19. This also uses GSK's AS03 adjuvant.

The latest deal, part of the Trump administration’s Operation Warp Speed effort to have a Covid vaccine available before the US national elections on Nov. 3, adds $2.1 billion to the $256 billion Sanofi is already receiving from the US government for vaccine development.

Part of the cash injection that Sanofi has earmarked for clinical trials and manufacturing scale-up, as well as delivery of an initial 100 million doses, will go to GSK. Longer term, the US has an option for the supply of an additional 500 million doses. Sanofi said this will result in a “significant increase” in capacity.

The grant awarded to Sanofi and GSK is the largest given to date under Operation Warp Speed, exceeding the recent $1.6 billion it pledged to US drugmaker Novavax for its adjuvanted nanoparticle vaccine candidate.

Sanofi said it expects to have a phase 1/2 study ready to start in September, followed by a phase 3 up to the end of 2020. If the results are positive, the two European drugmakers can apply to the US Food and Drug Administration (FDA) for approval in the first half of 2021.

In parallel, Sanofi and GSK are scaling up manufacturing of the antigen and adjuvant to produce up to 1 billion doses per year globally and stress that they are “committed to making the vaccine available globally.” Separately, the French partner is also developing a messenger RNA (mRNA) vaccine candidate in partnership with Translate Bio.

Although the mRNA technology being used by Moderna as well as Germany’s BioNTech, which has a development pact with US pharma giant Pfizer, is being touted as the cheapest and fastest path toward getting a vaccine on the market, this route has never been traveled commercially. This is why so Warp Speed’s management – headed by a former GSK executive – may be hedging its bets, analysts said.

Supply deal with UK may be worth £500 million

A day before announcing the latest US vaccine deal, Sanofi and GlaxoSmithKline said they had signed a provisional agreement with the UK to supply at least 60 million doses of the recombinant protein candidate, subject to a final contract. Financial terms were not disclosed but earlier reports hinted that it could be worth £500 million.

Through the agreement with the two drugmakers, Kate Bingham, chair of the UK government’s vaccines taskforce, said, the Sanofi-GSK vaccine will be another type of vaccine to the three different types the UK has already secured.  “This diversity of vaccine types is important because we do not yet know which, if any, of the different types of vaccine will prove to generate a safe and protective response to Covid-19,” she added

Meanwhile, Sanofi and GSK have said that ongoing discussions with the European Commission about supply of the recombinant protein-based vaccine are at an advanced stage. The doses would be manufactured in European countries including France, Belgium, Germany and Italy. Days earlier, the Reuters news agency suggested that these talks had stalled due to differences over pricing and liability.