ROCKVILLE, Md., Oct. 8, 2012 (GLOBE NEWSWIRE) -- Novavax, Inc. (Nasdaq:NVAX) today announced that enrollment has begun in a Phase 2 dose-ranging clinical trial of its respiratory syncytial virus (RSV) vaccine candidate in women of childbearing age. The study is being conducted in collaboration with PATH, an international nonprofit organization that transforms global health through innovation, which is providing approximately $2 million in funding to support the trial. This randomized, blinded, placebo-controlled Phase 2 study will evaluate the immunogenicity and safety of two dose levels of Novavax's RSV-F protein nanoparticle vaccine with and without aluminum phosphate as an adjuvant. The study will enroll 330 women of childbearing age who will receive either one or two intramuscular injections at each dose level of vaccine or placebo at days 0 and 28. Safety and immunogenicity will be evaluated over six and four month periods, respectively. "In addition to evaluating the safety and immunogenicity of our RSV vaccine candidate in an important patient population, this study will be crucial for both the determination of the optimal dosing regimen for future studies and the potential adjuvant effect of aluminum phosphate, an adjuvant used in U.S. licensed products," said Gregory Glenn M.D., Senior Vice President and Chief Medical Officer of Novavax. "Previous clinical and preclinical findings have suggested that immunization with our nanoparticle vaccine produces functional neutralizing antibodies to multiple sites on the F protein. We expect to report top-line results from this trial, through Day 56 observations, in the first quarter of 2013." About RSV and Maternal Immunization RSV is the most common cause of childhood respiratory infection globally, with a disease burden of 64 million cases and approximately 160,000 deaths annually. Severe RSV disease necessitates 3.4 million hospital admissions per year and disproportionately affects infants below six (6) months of age. A severe episode of RSV bronchiolitis can lead to recurrent bouts of reactive airway disease/asthma for many years after the initial event. It is a highly contagious virus that occurs as a predictable epidemic from late autumn through early spring in the U.S. and other northern hemisphere regions and can have more than two annual peaks in tropical climates. RSV disease burden in low-resource countries is significant, and available data indicate that the virus is responsible for a high proportion of childhood acute lower respiratory infection in these settings, particularly in the first few months of life. Currently, there is no approved RSV prophylactic vaccine available. Maternal immunization is a widely practiced strategy for protecting infants in a variety of diseases, such as neonatal tetanus and is currently recommended by the Center for Disease Control's Advisory Committee on Immunization Practices for battling infant pertussis. Maternal immunization can lead to heightened antibodies in infants and thereby protects them against the targeted disease, and thus may be a key strategy to protect young infants from RSV illness.