Mixing COVID-19 Vaccine Study Adds Two Other Vaccines

Researchers conducting the Com-Cov clinical study investigating alternating doses of the AstraZeneca and the Pfizer-BioNTech COVID-19 vaccines announced that the program now includes the Moderna and Novavax vaccines.

Study volunteers will receive either the AstraZeneca or Pfizer vaccine, will be randomly allocated to receive either the same vaccine for their second dose or a dose of the COVID-19 vaccines produced by Moderna or Novavax.

The six new ‘arms’ of the Com-Cov trial will each recruit 175 candidates, adding a further 1,050 recruits into this innovative program. 

Led by the University of Oxford, run across nine National Institute for Health Research supported sites by the National Immunisation Schedule Evaluation Consortium, and backed through funding from the Vaccines Taskforce and the Coalition for Epidemic Preparedness Innovations, the additional study will seek to recruit adults aged over 50 who have received their first, or ‘prime’ vaccination in the past 8-12 weeks.

Matthew Snape, Associate Professor in Paediatrics and Vaccinology at the University of Oxford, and Chief Investigator on the trial stated in a press release issued on April 13, 2021, ‘The focus of both this and the original COM-COV study is to explore whether the multiple COVID-19 vaccines that are available can be used more flexibly.”

‘If we can show that these mixed schedules generate an immune response that is as good as the standard schedules, and without a significant increase in the vaccine reactions, this will potentially allow more people to complete their COVID-19 immunization course more rapidly.”

Maryland-based Novavax, Inc. confirmed on April 14th its recombinant protein vaccine candidate, NVX-CoV2373, is one of four COVID-19 vaccines that will be studied to evaluate the potential for combined regimens.

"Novavax' addition to this important study reflects the urgency of finding innovative ways to protect as many people as possible in a dynamic pandemic landscape," commented Filip Dubovsky, M.D., EVP, CMO, Novavax. 

"The potential utility of pooling public health resources, including all available vaccines, could help us get ahead of an evolving virus."

Under the protocol, which is designed as a non-inferiority study, participants will be followed for reactogenicity (safety) and immune responses. 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 regimen before it is made available to the public.

NVX-CoV2373 is being evaluated in two pivotal Phase 3 trials, a trial in the U.K that demonstrated the efficacy of 96.4% against the original virus strain and 89.7% overall, and the PREVENT-19 trial in the U.S. and Mexico that began in December 2020.

NVX-CoV2373 is a protein-based vaccine candidate engineered from the genetic sequence 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 adjuvanted with Novavax' patented saponin-based Matrix-M™ 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 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.

As of April 15, 2021, the NVX-CoV2373 vaccine candidate has not received emergency authorization from either the U.S FDA or the European Medicines Agency.

PrecisionVaccinations publishes research-based news.

Note: updated for clarity.