AstraZeneca’s MedImmune subsidiary has filed for approval in the USA for motavizumab, the follow-up to its blockbuster respiratory infection drug Synagis.

The company has submitted a Biologics License Application to the US Food & Drug Administration for motavizumab, a monoclonal antibody. The file is based on data from more than 6,000 high-risk paediatric patients suffering from serious disease caused by respiratory syncytial virus (RSV).

MedImmune derived motavizumab from Synagis (palivizumab), another RSV-specific MAb already recommended for children at high-risk of developing serious RSV disease. If approved, the firm will market the drug through its own sales force in the USA and through a partnership with Abbott Laboratories elsewhere.

Each year, up to an estimated 125,000 infants in the USA are hospitalised with severe RSV infections, said MedImmune which notes that RSV causes up to 1.7 million physician office visits and more than 230,000 hospital outpatient emergency room visits per year. The filing is one of three that AstraZeneca intends to submit this year.

At a recent investors meeting, MedImmune outlined a number of asthma projects it has in Phase I and II which are studying MAbs that target the interleukin-5, IL-9 and IL-13 receptors. The unit also described numerous oncology trials that are underway, including those for IPI-504 (retaspimycin), which is partnered with Infinity Pharmaceuticals.