Novavax, Inc. (Nasdaq: NVAX), a biotechnology company dedicated to developing and commercializing next-generation vaccines for serious infectious diseases, today announced that NVX-CoV2373, its protein-based COVID-19 vaccine, is included in two trials now underway to evaluate its vaccine's safety, immunogenicity, and reactogenicity as a booster amidst the ongoing COVID-19 pandemic. Both studies have initiated participant enrollment and will help to extend knowledge of how a range of vaccines, including Novavax' COVID-19 vaccine, can be used as boosters following primary immunization.

"Additional COVID-19 booster studies are important to support vaccine choice for individuals, healthcare providers, and public health authorities," said Filip Dubovsky, M.D., Chief Medical Officer, Novavax. "Our COVID-19 vaccine has already been recommended by multiple national policy bodies for both primary vaccination and booster settings in individuals 18 years of age and older. We look forward to adding to this body of evidence to support the expanded use of our protein-based vaccine."

Novavax is participating in an ongoing Phase 1/2 trial sponsored by the National Institute of Allergy and Infectious Diseases (NIAID) to assess homologous and heterologous boosting regimens in participants who received a primary series of a COVID-19 vaccine which has received full approval or Emergency Use Authorization (EUA) from the U.S. Food and Drug Administration (FDA). Participants will be given a third dose (> 12 weeks later) of either NVX-CoV2373 or one of the three COVID-19 vaccines that have already received EUA or full authorization from the FDA. The study is enrolling approximately 1,130 healthy individuals aged 18 years or older, about 180 of whom will receive NVX-CoV2373 as a heterologous booster. The trial is being conducted at approximately 10 clinical research sites and its primary objectives are to evaluate safety, reactogenicity, and immunogenicity of delayed heterologous or homologous vaccine doses after EUA dosed vaccines. Participants will be followed for 12 months, with topline results expected later this year and full results expected in 2023.

Novavax' COVID-19 vaccine is also being evaluated in an observer-blinded Phase 3 study in the United Arab Emirates (UAE) to assess homologous versus heterologous boosting of participants who have already been immunized with Sinopharm's COVID-19 vaccine. The safety and immunogenicity of a single booster dose of Novavax' COVID-19 vaccine in adults previously vaccinated with Sinopharm's COVID-19 vaccine will be evaluated. The study is enrolling approximately 1,000 participants aged 18 years or older at two centers in Abu Dhabi with the goal of providing data to support boosting with NVX-CoV2373 in the large number of individuals who have been vaccinated with inactivated vaccines globally. Participants will be followed for six months, with full results expected during the fourth quarter of 2022. The Ministry of Health and Prevention approved NVX-CoV2373 for emergency use in the UAE in December.

For more information about the NIAID-sponsored study, read here on clinicaltrials.gov. For more information about the study in the UAE, read here on clinicaltrials.gov. NVX-CoV2373 has not yet been authorized for use by the FDA, nor has it received heterologous or homologous booster approval in all the countries where it's been authorized.

• NVX-CoV2373 is contraindicated in persons who have a hypersensitivity to the active substance, or to any of the excipients.
• Events of anaphylaxis have been reported with administration of COVID-19 vaccines. Appropriate medical treatment and supervision should be available in case of an anaphylactic reaction following the administration of the vaccine. Close observation for at least 15 minutes is recommended and a second dose of the vaccine should not be given to those who have experienced anaphylaxis to the first dose of NVX-CoV2373.
• Anxiety-related reactions, including vasovagal reactions (syncope), hyperventilation, or stress‐related reactions may occur in association with vaccination as a psychogenic response to the needle injection. It is important that precautions are in place to avoid injury from fainting.
• Vaccination should be postponed in individuals suffering from an acute severe febrile illness or acute infection. The presence of a minor infection and/or low-grade fever should not delay vaccination.
• NVX-CoV2373 should be given with caution in individuals receiving anticoagulant therapy or those with thrombocytopenia or any coagulation disorder (such as haemophilia) because bleeding or bruising may occur following an intramuscular administration in these individuals.
• The efficacy of NVX-CoV2373 may be lower in immunosuppressed individuals.
• Administration of NVX-CoV2373 in pregnancy should only be considered when the potential benefits outweigh any potential risks for the mother and foetus.
• The effects with NVX-CoV2373 may temporarily affect the ability to drive or use machines.
• Individuals may not be fully protected until 7 days after their second dose. As with all vaccines, vaccination with NVX-CoV2373 may not protect all vaccine recipients.
• The most common adverse reactions observed during clinical studies were headache, nausea or vomiting, myalgia, arthralgia, injection site tenderness/pain, fatigue, and malaise.