Complementary difficulties

The failure of TP10 from Avant Immunotherapeutics Inc. to meet its primary endpoint in a Phase II trial of patients undergoing cardiac surgery is the second such setback for a compound targeting complement in a cardiovascular indication. Just over a year ago, Alexion Pharmaceuticals Inc.'s Pexelizumab missed its primary endpoint in a Phase IIb trial. But both companies believe that complement remains a good target for cardiovascular and other indications.

In AVAN's 564-patient trial of TP10, the soluble form of complement receptor 1 (sCR1) did not meet the combined primary endpoint of a decrease in mortality, incidence of myocardial infarction (MI), prolonged intubation and prolonged cardiac support...