Novavax Vaccine Shown to Be 96 Percent Effective Against Original SAR-Cov-2 Virus
Novavax said its COVID-19 vaccine demonstrated 96.4 percent efficacy against mild, moderate and severe forms of the original SARS-CoV-2 strain in the final analysis from its phase 3 UK trial.
The UK trial enrolled more than 15,000 participants ages 18 to 84, significantly including 27 percent of participants over age 65. While the vaccine’s efficacy was 96.4 percent against the original coronavirus strain, it fell to 86.3 percent against variant B.1.1.7, the variant first identified in the UK, making the vaccine’s overall efficacy 89.7 percent, the company said.
Novavax also announced results from a smaller, phase 2b trial conducted in South Africa, where the vaccine demonstrated an efficacy of just 55.4 percent in 2,665 HIV-negative participants, with most enrollees exposed to the coronavirus mutant strain first identified in that country.
But for both trials, NVX-CoV2373 offered 100 percent protection against severe disease, including hospitalization and death. The results are similar to interim data released in January showing the vaccine had high efficacy against the original SARS-CoV-2 virus, but diminished efficacy against the South African variant (DID, Jan. 29).
Novavax is still awaiting results from a U.S./Mexico phase 3 trial begun in December, which finished enrolling 30,000 participants last month (DID, Feb. 23). Primary results are expected by the end of March, according to ClinicalTrials.gov. The U.S. data could be used to support an Emergency Use Authorization (EUA) filing with the FDA, along with the UK trial results, which could also help support authorization filings in Great Britain and the EU.
Novavax plans to file for clearance with the UK’s Medicines and Healthcare products Regulatory Agency first, before seeking an EUA from the FDA, both of which will occur during the second quarter of this year, a company spokesperson told FDAnews.
Novavax’s vaccine is also currently under a rolling review with the European Medicines Agency, and other global regulators, and a submission for authorization will occur when all data are final, also expected in the second quarter, the spokesperson said. ― Jason Scott