Novavax on Monday announced the start of the Phase 3 trial of its Covid-19 vaccine in the United States and Mexico. It is the fifth company to launch a large-scale trial of a coronavirus vaccine in the United States.

The trial for the vaccine candidate, known as NVX-CoV2373, will evaluate safety, efficacy and immune response in up to 30,000 people age 18 and older. It builds on Phase 1/2 studies that demonstrated that the vaccine provoked an immune response and appeared to be safe. The trial is examining whether the vaccine prevents Covid-19 symptoms, as well as moderate or severe Covid-19 symptoms. All participants will be followed for 24 months following their second injection.

Two-thirds of participants will be assigned to randomly receive two injections of vaccine administered 21 days apart, the remaining one-third will receive a placebo. The trials sites are in locations that currently have high transmission rates "to accelerate the accumulation of positive cases that could show efficacy," the release says.

Novavax says it aims for at least 25% of the study population to be age 65 or older, at least 15% to be Black, at least 10 to 20% Latinx and 1-2% American Indian.

"With the COVID-19 pandemic raging around the globe, this trial is a critical step in building the global portfolio of safe and effective vaccines to protect the world's population," Stanley C. Erck, president and chief executive officer of Novavax, said in a news release. The trial is being funded with up to $1.6 billion from Operation Warp Speed.

Novavax is also currently conducting a Phase 3 clinical study in the United Kingdom, a Phase 2b trial in South Africa and a Phase 1/2 continuation in the US and Australia, data from which are expected as soon as early first quarter 2021.

Two vaccines, from Pfizer/BioNTech and Moderna, have received emergency use authorization from the US Food and Drug Administration. Both began Phase 3 trials in the US in July and enrolled over 30,000 participants. Both are two dose vaccines and have been shown to have 95% and 94.1% efficacy respectively.

AstraZeneca began the Phase 3 US trial of its coronavirus vaccine in September. Johnson & Johnson, which is testing a single-dose vaccines, expects efficacy results from its Phase 3 trial by January or February.

Story Source: https://edition.cnn.com/2020/12/28/health/novavax-covid-vaccine-trial-phase-3/index.html