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MEDI8897 Receives Fast Track Designation

MEDI8897 Receives Fast Track Designation by the FDA for the Prevention of Respiratory Disease

April 9, 2015

AIMM Therapeutics announced today that its partner Medimmune has received fast track designation from the U.S. Food and Drug Administration (FDA) for the development of MEDI8897. This high-potency, extended half-life monoclonal antibody (mAb) is being investigated for the prevention of lower respiratory tract illness (LRTI) caused by respiratory syncytial virus (RSV) in infants and young children. The FDA’s fast track program is designed to expedite the development and review of drugs that treat serious conditions and fill an unmet medical need.

Recognizing that the currently approved antibody, palivizumab, only protects a small subpopulation of vulnerable infants, AIMM used its proprietary technology to select highly potent antibodies directly from elite responders who developed strong resistance to RSV. Using AIMM’s D25 antibody, Medimmune engineered it to yield MEDI8897 which has an extended half-life capable of covering the entire RSV season. The combination of the high potency of D25 and long half-life promises to increase the number of infants who are protected from LRTI caused by RSV through passive immunization of all infants, term and preterm.

“While the burden and seriousness of RSV disease has kept it a global priority for vaccine development for more than 50 years, it is well recognized that a significant unmet medical need continues to exist for the prevention of RSV in all infants worldwide,” said Steve Projan, PhD, FAAM, Senior Vice President, R&D and Infectious Diseases & Vaccines Innovative Medicines Unit Head, MedImmune. “We are working with a sense of urgency to develop a next-generation RSV mAb that we believe has the potential to benefit hundreds of thousands more infants, both in the U.S. and around the world. If successful, the fast track designation will enable us to more quickly deliver a preventative solution.”

RSV is the most prevalent cause of lower respiratory tract infections among infants and young children, resulting in annual epidemics worldwide. In children younger than one year of age, RSV is the most common cause of bronchiolitis, an inflammation of the small airways in the lung, and pneumonia, an infection of the lungs. Severe RSV disease causes approximately 125,000 hospitalizations and up to 400 infant deaths each year in the United States alone. There is currently no treatment for RSV once it’s contracted, nor is there an approved preventative therapy for healthy populations.

As part of its development program, MedImmune is applying its proprietary technology to increase the half-life of MEDI8897, so that only one dose will be needed for the entire RSV season. In preclinical in vivo and in vitro studies, MEDI8897 exhibited potent antiviral activity against a diverse panel of RSV A and B clinical isolates, demonstrating broad-spectrum antiviral activity against RSV. MEDI8897 is currently being investigated in a Phase 1 study to evaluate the safety, tolerability, and pharmacokinetics of the antibody in healthy adults. Based upon analysis of interim data from this study, a separate Phase 1b/2a study has been initiated to examine MEDI8897 in healthy preterm infants.

About MEDI8897

MEDI8897 is an investigational recombinant human immunoglobulin G1 kappa (IgG1κ) monoclonal antibody (mAb) with an extended half-life that neutralizes RSV by binding the prefusion conformation of the RSV fusion (F) protein expressed on virions and infected cells. MedImmune is pursuing development of MEDI8897 for the passive immunization of all infants entering their first respiratory syncytial virus (RSV) season and children with chronic lung disease (CLD) or congenital heart disease (CHD) entering their first and second RSV season for the prevention of lower respiratory tract illness (LRTI) caused by RSV.