United Thera drops OvaRex after it fails

USA-based United Therapeutics Corp plans to discontinue the development of OvaRex, its monoclonal antibody for advanced ovarian cancer, after the drug failed to meet the primary endpoint in two pivotal trials.

The identical studies, known as IMPACT I and II, were randomized, double-blind, placebo-controlled trials which sought to confirm data observed in a subset analysis of a prior randomized Phase II study, which suggested the potential of OvaRex to extend the time-to-disease relapse among patients who had completed front-line therapy.

According to the US firm, the studies demonstrated no difference between active arms, standard-of-care followed by OvaRex and control, which consisted of standard-of-care followed by placebo. The company added that the results of both studies were consistent with each other. Based on the preliminary results from the IMPACT trials, United's subsidary, Unither Pharmaceuticals, intends to cease further development of the entire platform of OvaRex antibodies. The firm said it does not yet have a precise estimate of write-down charges, but noted that it has approximately $7.0 million in assets related to this program that are subject to write-down during fourth-quarter 2007.