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(Alliance News) -Â GlaxoSmithKline PLC and Sanofi SA on Thursday said they have started enrollment in a phase three study of their Covid-19 vaccine candidate.
The global study will recruit more than 35,000 volunteers from several countries, including the US, Asia, Africa and Latin America.
The primary endpoint is the prevention of symptomatic Covid-19 in "SARS-CoV-2 naive adults", with secondary endpoints of preventing severe and asymptomatic infection. The phase three study follows interim phase two results which showed that the adjuvanted recombinant Covid-19 vaccine candidate achieved high rates of neutralising antibody responses in all adult age groups, with 95% to 100% seroconversion rates.
In a two-stage approach, the phase three study will at first investigate the efficacy of a vaccine formulation targeting the original D.614 virus before then evaluating a second formulation targeting the B.1.351, or South Africa, variant.
"Recent scientific evidence shows that antibodies created against the B.1.351 variant may provide broad cross-protection against other more transmissible variants," noted UK-headquartered GSK and Paris-based Sanofi.
Further, the global spread of the phase three trial will allow for evaluation of the vaccine candidate against a variety of circulating variants.
The two added: "Following encouraging interim results from the recent phase 2 study, the companies will also begin clinical studies in the coming weeks to assess the ability of the adjuvanted recombinant-protein Covid-19 vaccine candidate to generate a strong booster response regardless of initial vaccine platform received."
By Lucy Heming;Â lucyheming@alliancenews.com
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