Clinical trial: the efficacy and safety of oral PF-03491390, a pancaspase inhibitor - a randomized placebo-controlled study in patients with chronic hepatitis C

P>Background Elevated serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) reflect hepatocellular injury in patients with chronic hepatitis C virus (HCV). Increased apoptosis and activated caspases are present in these patients. PF-03491390 inhibits multiple caspases and lowers serum AST and ALT levels in patients with chronic liver diseases. Aim To determine if treatment with an oral pancaspase inhibitor could reduce serum AST and ALT in patients with HCV. Methods Double-blind, randomized, placebo-controlled, parallel-dose study in 204 patients treated with placebo or PF-03491390 (5, 25 or 50 mg) orally twice daily (b.d.) for up to 12 weeks. Serum AST and ALT were monitored weekly. Results Significant reductions in serum AST and ALT were observed within 1 week of initiating PF-03491390 in all treatment groups (P < 0.0001). These reductions in AST and ALT were maintained throughout the 12 week treatment period and returned to baseline levels when PF-03491390 was discontinued. Increasing the dose did not further lower AST or ALT. The most frequently reported adverse events were headache and fatigue. Conclusion PF-03491390 significantly reduced serum AST and ALT levels in patients with chronic HCV, and was well tolerated over 12 weeks.