CIPROSTENE PHASE III REANALYSIS SHOWS 42% REDUCTION IN RESTENOSIS

CIPROSTENE PHASE III REANALYSIS SHOWS 42% REDUCTION IN RESTENOSIS following balloon angioplasty. The reanalysis of the study results of the Upjohn drug was presented by Albert Raizner, MD, Baylor College of Medicine, at the American College of Cardiology annual meeting March 17. The original analysis of the study, reported in 1988, found only a trend in restenosis reduction in ciprostene-treated patients over placebo. The reanalysis found that six months after patients had undergone percutaneous transluminal coronary angioplasty (PTCA), the average minimal lumen diameter of patients had decreased by .33 mm in the ciprostene group compared to .57 mm in the placebo group, a statistically significant difference of 42%. In the study, 311 patients were randomized to a 15-minute intracoronary infusion of ciprostene (40 nanograms/minute to 120 ng/min.) or placebo prior to PTCA. After angioplasty, patients received an intravenous infusion of ciprostene or placebo for 48 hours. Approximately 70% of the patients had quantitative coronary angiographs conducted post-PTCA and at six-months follow-up. Ciprostene therapy also reduced repeat angioplasty, coronary bypass surgery and myocardial infarction by 40%-50% in the U.S. study, Raizner reported. A European Phase III trial in 331 patients confirms the U.S. results with ciprostene, he said. When the data in the U.S. and European trials were combined, ciprostene was associated with a 33% reduction in total clinical adverse events. Repeat angioplasties were decreased by 28%, coronary artery bypass grafts (CABGs) by 47%, and myocardial infarctions by 53%. In addition, there was a reduction in deaths in the ciprostene patient group. Raizner explained that the reanalysis was conducted because the previous analysis of the Phase III trial was based on visual interpretation of angiographic data, by which only percentage of stenosis can be assessed, rather than quantitative analysis of the angiograms. At a press briefing during the ACC meeting, Raizner said Upjohn "shelved" ciprostene after learning of the marginal results following the original analysis of the study. Upjohn says it has no plans to resume development of ciprostene but that it would consider it as an outlicensing candidate.