UW Vaccine & Treatment Evaluation Unit

December 20, 2021

Novavax Letter to PREVENT-19 Trial Participants

December 2021


To participants in our PREVENT-19 clinical trial:

We remain sincerely grateful for your participation in the PREVENT-19 clinical trial and your significant contribution to medical research addressing COVID-19. We are writing to provide an update on Novavax’ COVID-19 vaccine program. Foremost is the exciting news that the Novavax COVID-19 vaccine demonstrated high level efficacy in our PREVENT-19 Phase 3 trial in the U.S. and Mexico (90% protection overall against COVID-19 illness and 100% against moderate-to-severe disease during the first 3 months in the trial).

Regulatory filing. Based on results from the PREVENT-19 trial and others,Novavax submissions for emergency use authorization have been approved or are under review in multiple countries around the world and will be submitted soon in the United States. The Novavax COVID-19 vaccine is also under review with the World Health Organization for Emergency Use Listing (EUL). As the first protein-based option filed with a major regulatory agency based on clinical data, we are pleased with the prospect of offering this much-needed vaccine to the public.

Proof of vaccination. The CDC developed a modified proof of vaccination card that verifies that participants in PREVENT-19 who received two doses of vaccine in the trial are considered fully vaccinated. You should have received this card from your study staff. In response to entities in the U.S. not recognizing this card as proof of vaccination, we advocated further and are very pleased that the CDC posted the following statement on their website: “If a participant in a U.S.-based clinical trial has been documented to have received the full series of an “active” (not placebo) COVID-19 vaccine candidate, and vaccine efficacy has been independently confirmed (e.g., by a data safety monitoring board), the participant can be considered fully vaccinated 2 weeks after they completed the vaccine series. Currently, the Novavax COVID-19 vaccine meets these criteria.” This statement can be found at the following link: Interim Clinical Considerations for Use of COVID-19 Vaccines | CDC in the section entitled, “People who received COVID-19 vaccine as part of a clinical trial”.

Booster doses. The possibility that booster doses would be needed for COVID-19 vaccines has always been a consideration, and Novavax has been carefully evaluating the durability of immunity among trial participants in collaboration with the Data Safety Monitoring Board and public health authorities. On November 29, 2021, the CDC strengthened its booster recommendation in the US to include that everyone 18 years of age or older should get a booster shot at least six months after their initial COVID-19 vaccine series. As a clinical trial participant who qualifies as being “fully vaccinated,” you are included in the CDC recommendation, as described at the link provided above. You may choose an authorized booster outside of this trial, or the Novavax booster as part of this clinical trial, when available. We are pleased to inform that a booster vaccination with the Novavax COVID-19 vaccine will be offered to eligible participants on the PREVENT-19 clinical trial, with roll-out expected in December 2021 or January 2022.

A press release describing current data on the Novavax COVID-19 vaccine, including information about antibodies against the delta variant can be found at: https://ir.novavax.com/2021-08-05-Novavax-Reports-Second-Quarter-2021-Financial-Results-and-Operational-Highlights. Information regarding the Novavax COVID-19 vaccine and the omicron variant is being developed and will be shared when available.

Again, we sincerely thank you for your commitment to the trial, and for contributing to data that will allow this vaccine to have a public health impact globally.

Kind regards,

The Novavax PREVENT-19 Team

The CoVPN Co-Chairs