Another Pipeline Setback For MerckThis morning Merck & Co. (MRK) announced disappointing top-line results of its 2,033-patients phase III PROTECT study of rolofylline (MK-7418), under development for acute heart failure. The candidate failed to meet both the primary (improve symptoms of acute heart failure) and secondary (reduce the risk of death or cardiovascular or renal re-hospitalization 60 days after treatment and reduce the incidence of persistent kidney impairment) endpoints.Acute heart failure is the leading cause of hospitalizations of patients over 65, is associated with a high rate of mortality and currently has few treatment options. Rolofylline showed encouraging efficacy including improvement of shortness of breath and effectiveness in preserving renal function compared to placebo in a phase III dose ranging study. This data was presented at the 2008 American College of Cardiology meeting.We had expected Merck to file for FDA approval of ...