On Sept. 16, 2021, Novavax announced its participation in a newly expanded Phase 2 clinical trial called Comparing COVID-19 Vaccine Schedule Combinations – Stage 3 (Com-COV3), led by the University of Oxford and funded by the UK Vaccines Taskforce and the National Institute for Health Research. Novavax’s recombinant nanoparticle COVID-19 vaccine candidate, NVX-CoV2373, was one of the three COVID-19 vaccines that were to be studied in adolescents to evaluate the potential for combined regimens that mix vaccines from different manufacturers to achieve immune protection against COVID-19.

Com-COV3 will include at least 360 adolescents 12-16 years of age. Volunteers will receive an authorized vaccine as a first dose and then at least 8 weeks later will receive one of three different vaccines as a second dose. All participants will be randomly allocated at the time of the second dose to receive either a full dose or half dose of the same vaccine given for the first dose, a full dose of the Novavax vaccine or a half dose of a different authorized vaccine. The research will compare the immune system responses from those who receive a heterologous regimen to those who receive a homologous regimen.

Under the protocol, participants will be followed for reactogenicity (safety) and immune responses. Results from the study are expected within a few months. The UK Medicines and Healthcare products Regulatory Agency (MHRA) and Joint Committee on Vaccination and Immunisation (JCVI) will formally assess the safety and efficacy of any new vaccination process before advising whether it is rolled out.

Novavax is also participating in University of Oxford’s Com-COV2 study, in which NVX-CoV2373 is one of four COVID-19 vaccines being studied to evaluate the potential for combined regimens that mix vaccines from different manufacturers to achieve immune protection against COVID-19. Results from Com-COV2 are expected in the coming weeks.

NVX-CoV2373 is a protein-based vaccine candidate engineered from the genetic sequence of the first strain of SARS-CoV-2, the virus that causes COVID-19 disease. NVX-CoV2373 was created using Novavax’ recombinant nanoparticle technology to generate antigen derived from the coronavirus spike (S) protein and is formulated with Novavax’ patented saponin-based Matrix-M™ adjuvant to enhance the immune response and stimulate high levels of neutralizing antibodies. NVX-CoV2373 contains purified protein antigen and can neither replicate, nor can it cause COVID-19. In preclinical studies, NVX-CoV2373 induced antibodies that blocked the binding of spike protein to cellular receptors and provided protection from infection and disease. It was generally well-tolerated and elicited robust antibody response in Phase 1/2 clinical testing.

NVX-CoV2373 is being evaluated in two pivotal Phase 3 trials: a trial in the U.K. that demonstrated efficacy of 96.4% against the original virus strain, 86.3% against the Alpha (B.1.1.7) variant and 89.7% efficacy overall; and the PREVENT-19 trial in the U.S. and Mexico that demonstrated 100% protection against moderate and severe disease and 90.4% efficacy overall. It is also being tested in two ongoing Phase 2 studies that began in August 2020: A Phase 2b trial in South Africa that demonstrated 55% efficacy overall in HIV-negative participants and 48.6% efficacy against a newly emerging escape variant first described in South Africa, and a Phase 1/2 continuation in the U.S. and Australia.

NVX-CoV2373 is stored and stable at 2°- 8°C, allowing the use of existing vaccine supply chain channels for its distribution. It is packaged in a ready-to-use liquid formulation in 10-dose vials.