June 25, 2012
CytoPharm and Amarillo Biosciences reported results from a phase II trial of interferon-alpha lozenges for the treatment of thrombocytopenia in patients with hepatitis C virus. This randomized, dose-ranging study enrolled 169 patients in viral remission who had just completed at least 24 weeks of treatment with injectable interferon-alpha (IFNa) and Ribavirin. Subjects received oral lozenges containing 500 or 1500 international units (IU) of natural human IFNa or matching placebo for 24 weeks, followed by 24 weeks of untreated observation. At completion of the study, 81% of subjects who received 500IU lozenges normalized their mean platelet count versus only 42% in the placebo group. In the 40% of subjects who had mild liver fibrosis, only 12% of the 500IU arm experienced virological relapse by the end of the study, compared to 32% in the placebo group—a 63% reduction in relapse rate. The drug was well tolerated. Phase III studies are currently underway.