News & Media
New Data from Novavax Phase 3 Prepare™ Trial of ResVax™ Presented at 2019 IDSOG Annual Meeting
Aug 12, 2019
Data demonstrate significant vaccine efficacy against infant pneumonia through the first year of life

GAITHERSBURG, Md., August 12, 2019 – Novavax, Inc. (NASDAQ: NVAX), a late stage biotechnology company developing next-generation vaccines for serious infectious diseases, today announced the presentation of new data from the company’s Prepare™ trial, a global Phase 3 clinical trial of ResVax™, an aluminum adjuvanted respiratory syncytial virus (RSV) fusion (F) protein recombinant nanoparticle vaccine. Geeta K. Swamy, M.D., Associate Professor of Obstetrics and Gynecology and Vice Dean and Associate Vice Provost for Scientific Integrity at Duke University, made the presentation at the 2019 IDSOG Annual Meeting held in Big Sky, Montana. 

Dr. Swamy’s presentation included new observations based on the recently completed analyses of the 1-year safety data, including a 56.9% (95% CI 34.5, 71.7%) reduction in the incidence of serious adverse events (SAEs) diagnosed as pneumonia, with confirmation by chest x-ray, that extended through the first year of life. A similar efficacy of approximately 50% (95% CI 31.3, 62.7%) was found for all SAEs with a clinical diagnosis of pneumonia, also extending over a year. When x-ray-confirmed pneumonia SAEs associated with detection of RSV were considered, efficacy was 72.9% (95% CI. 45.7, 86.5%) through 180 days of life, the last time point at which active detection of RSV was carried out.

“Ongoing analysis of the Prepare trial data is teaching us more about how and where the vaccine was most efficacious in reducing RSV infections and its most severe complications,” said Louis F. Fries III, M.D., Chief Medical Officer of Novavax. “Based on the incidence rate for clinical pneumonia SAEs in placebo subjects in the Prepare trial and the vaccine’s efficacy in reducing this rate, ResVax could have a public health impact, in terms of vaccine-preventable disease incidence or number of women needed to vaccinate to prevent one case of infant pneumonia, that is similar or in excess of pneumococcal conjugate vaccines for similar outcomes. Such insights are valuable as we explore potential regulatory and clinical development paths forward to deliver an effective vaccine to address a serious global unmet need.”

Please click here to view a PDF of Dr. Swamy’s presentation along with other scientific presentations.

About ResVax™ and the Prepare Trial

ResVax is an RSV fusion (F) protein recombinant nanoparticle vaccine with aluminum phosphate as an adjuvant. It is being developed to protect infants from RSV disease via maternal immunization, which may offer the best method of protection from RSV disease in infants through the first months of life. In February 2019, Novavax announced top-line data from Prepare™, a global Phase 3 clinical trial in 4,636 pregnant women, at least 3,000 of whom have received the vaccine, and their infants. Prepare is supported by an $89.1 million grant from the Bill & Melinda Gates Foundation (BMGF).

About Novavax

Novavax, Inc. (NASDAQ: NVAX), is a late-stage biotechnology company that drives improved health globally through the discovery, development, and commercialization of innovative vaccines to prevent serious infectious diseases. ResVax™, its RSV vaccine for infants via maternal immunization, is the only vaccine in a Phase 3 clinical program and is designed to prevent severe lower respiratory tract infection which is the second leading cause of death in children under one year of age worldwide. Novavax is also advancing NanoFlu™, its quadrivalent influenza nanoparticle vaccine, to address key factors that can lead to the poor effectiveness of currently approved flu vaccines. Novavax is a leading innovator of recombinant vaccines; its proprietary recombinant technology platform combines the power and speed of genetic engineering to efficiently produce a new class of highly immunogenic nanoparticles addressing urgent global health needs.

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Novavax, Inc.
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