The European Commission has concluded exploratory talks with a clutch of vaccine manufacturers in recent weeks. Sanofi and GlaxoSmithKline reached that stage weeks ago, setting the Commission up to source up to 300 million doses of their adjuvanted recombinant protein-based vaccine. Talks with Johnson & Johnson over the supply of up to 400 million doses of its viral vector-based vaccine have also advanced beyond the exploratory stage.
As such, while the Commission has only finalized one agreement — a purchase of up to 400 million doses of AstraZeneca’s AZD1222 — the talks give it the makings of deals that would secure enough vaccines to administer a two-dose regimen to everyone in the European Union.
Despite that, the EU is still striving to source more vaccines. The latest news is that the Commission has completed exploratory talks with CureVac about buying an initial 225 million doses of its mRNA vaccine. The Commission is also seeking an option to buy an additional 180 million doses.
If the Commission closes all of the deals that have passed the stage of exploratory talks, it will have the means to buy more than 1.5 billion vaccine doses.
That is more than the EU, a region containing fewer than 500 million people, will need to vaccinate all of its citizens. However, the EU will only have access to 1.5 billion doses if all four of the vaccines covered by the deals demonstrate their safety and efficacy in phase 3 trials and win approval.
The history of phase 3 vaccine development shows it is plausible, perhaps probable, that one or more of the late-stage clinical trials will fail. The CureVac agreement could provide the EU with some insurance against that prospect.
While all the vaccines covered by the Commission’s deals target the coronavirus’ spike protein, they use different ways of triggering an immune response against the virus. AstraZeneca and J&J are using viral vectors, while Sanofi and GSK are deploying recombinant protein technology.
CureVac, in contrast, is delivering mRNA to trigger the production of a coronavirus protein by human cells. The immune system should recognize the protein as foreign, causing a reaction that equips the body to recognize and eliminate the coronavirus in the event the person is infected.
Moderna Therapeutics and the BioNTech-Pfizer collaboration are using the same basic approach, but the Commission is yet to advance talks with those organizations. CureVac is the first developer of a mRNA vaccine against COVID-19 to conclude exploratory talks with the Commission.
CureVac is well behind the other mRNA vaccine developers. While those vaccines could come to market this year, CureVac only expects to enter phase 2b/3 in the fourth quarter, suggesting it will be 2021 before its candidate wins approval.
