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Novavax’s fridge-friendly vaccine impresses

Novavax has unveiled results from a large clinical trial showing that its vaccine is 90.4% effective in preventing symptomatic COVID-19 and 100% protective against moderate and severe disease. Results from the phase 3 PREVENT-19 trial with 30,000 participants across the United States and Mexico had been eagerly awaited for the vaccine’s presumed advantages over existing jabs. Unlike the approved Pfizer, Moderna and Oxford/AstraZeneca vaccines, NVX-CoV2373 is a protein-based vaccine that relies on a well-established, traditional approach and is expected to have a benign safety profile. It can also be stored in refrigerators, a practical advantage that could boost distribution to low- and middle-income countries. The Novavax vaccine also appears to protect against escape by variants. The trial data were collected between January and April 2021, when the Alpha (B.1.1.7) variant, first identified in the United Kingdom, became the main strain circulating in the United States. The vaccine proved to be 93% effective in preventing symptomatic disease caused by variants of concern circulating during that period. Against symptomatic disease caused by the Beta mutation, an earlier study conducted in South Africa revealed a lower 51% efficacy among HIV-negative participants. It is unknown whether it can protect against the Delta variant, first identified in India, as that was unlikely to be circulating during the study period. NVX-CoV2373 is a MatrixM-adjuvanted recombinant nanoparticle vaccine engineered from the spike protein genetic sequence of the original SARS-CoV-2 strain. Phase 3 results were announced in a company press release and have yet to be published in a peer-reviewed journal. At the same time, another highly anticipated COVID-19 shot, CureVac’s mRNA vaccine CVnCov, failed to meet preset success criteria, delivering only 47% efficacy against symptomatic disease in a phase 2/3 trial, according to an interim analysis released by the company. CureVac says there were at least 13 variants circulating in the study population during the analysis, which may have reduced the vaccine’s efficacy. The German biotech still plans to file for European approval.

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Novavax’s fridge-friendly vaccine impresses. Nat Biotechnol 39, 784 (2021).

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