Vaccine Info

ResVax RSV Vaccine

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Last reviewed
June 11, 2022

ResVax RSV Vaccine Description for 2022

ResVax™ is an aluminum adjuvanted RSV fusion (F) protein recombinant nanoparticle vaccine for infants via maternal immunization.

Novavax developed its nanoparticle-based RSV vaccine for older adults and went through a large phase 2b clinical trial. However, in a large phase 3 trial, it was found ineffective. In light of the fact that the trial failed to meet its primary endpoints, the U.S. FDA and European Medicines Agency recommended conducting an additional Phase 3 clinical trial to confirm efficacy. As a result, Novavax is currently unblinding its next phase 3 trial in pregnant women. To accelerate RSV vaccine development, developers adopted the fail-fast approach.

The Bill & Melinda Gates Foundation (BMGF) has supported the Prepare trial for ResVax through a grant of up to $89.1 million; BMGF continues to financially support our efforts to conduct certain follow-up analyses of the Phase 3 data.

ResVax RSV Vaccine Indication

ResVax is indicated to prevent severe RSV disease, protecting infants as early as birth and during the first months of life when they are most at risk for hospitalization. RSV is the most common cause of lower respiratory tract infections and the leading viral cause of severe lower respiratory tract disease in infants and young children worldwide.

ResVax is administered to the maternal participant as an intramuscular (IM) Injection of RSV F Vaccine at 28-36 weeks Estimated Gestational Age (EGA).

ResVax RSV Vaccine News For 2015 - 2022

March 14, 2022 - A peer-reviewed article concluded: In a double-blind, randomized, placebo-controlled trial, administering an RSV vaccine to pregnant mothers reduced antimicrobial prescribing among their infants by 12.9% over the first three months of life.

July 21, 2021 - ResVax missed its primary efficacy endpoint in the pivotal PREPARE study. While it hit key secondary endpoints, the EMA and FDA have requested an additional confirmatory efficacy study before considering approval. The elderly segment offers the most commercial potential because of the large population size, high coverage rates that can be achieved, and the likely requirement for repeat seasonal vaccination. ResVax also failed to meet its primary efficacy endpoint in this subgroup in the RESOLVE study,

August 12, 2019 - Novavax presented new data from Novavax Phase 3 Prepare Trial of ResVax Presented at 2019 IDSOG Annual Meeting.

June 10, 2019 - Novavax Provides Updates on the Global Pathways to Licensure for ResVax™

February 28, 2019 - Novavax Announces Topline Results from Phase 3 PrepareTM Trial of ResVax™ for Prevention of RSV Disease in Infants via Maternal Immunization.

April 2015 - RSV F Nanoparticle Vaccine: Biological Rationale, Summary of the Clinical Data and Path Forward.

ResVax RSV Vaccine Clinical Trials

ResVax RSV vaccine has completed four clinical trials to date.

Data from our Prepare trial, initiated in December 2015, was announced in February 2019. The Prepare trial was conducted to determine whether ResVax reduced the incidence of medically significant RSV-positive LRTI in infants through a minimum of the first 90 days of life and up through the first six months of life. While these data did not meet the trial’s primary efficacy endpoint, it did demonstrate efficacy against a secondary endpoint by reducing RSV LRTI hospitalizations in treated infants. ResVax is thus the first RSV vaccine to show efficacy in a Phase 3 clinical trial and, in addition, to show important effects against a variety of prespecified exploratory endpoints and post hoc analyses. This included an approximately 60% reduction in RSV-related severe hypoxemia and an about 74% reduction in RSV-related, radiographically confirmed pneumonia through Day 90. As in previous clinical trials, ResVax also showed favorable safety and tolerability results.