ZymoGenetics commences Phase 2B study of PEG-Interferon lambda in hepatitis C

ZymoGenetics, Inc. (NASDAQ:ZGEN) today announced the initiation of the second part of a Phase 2 clinical trial with PEG-Interferon lambda (IL-29) and ribavirin in treatment-naïve patients with chronic hepatitis C virus (HCV) infection. ZymoGenetics is developing the investigational compound PEG-Interferon lambda in collaboration with Bristol-Myers Squibb Company (NYSE:BMY).

"We've moved forward into part B of our Phase 2 study of PEG-Interferon lambda in hepatitis C," said Eleanor L. Ramos, M.D., Senior Vice President and Chief Medical Officer of ZymoGenetics. "In part B, we expect to generate a substantial body of data to inform the design of Phase 3 studies, which will assess the potential role of PEG-Interferon lambda in addressing the unmet medical need for a safer, more effective treatment for hepatitis C."

The Phase 2 EMERGE study is an international, randomized multi-center clinical trial. The Phase 2a open label portion continues and is exploring a range of four doses. Based on antiviral effects after four weeks of treatment and accumulated safety data, doses were selected for the second part of the study (Phase 2b). A status report with top-line interim results from the Phase 2a clinical trial was disclosed by ZymoGenetics on May 4, 2010. The companies selected the three highest doses of PEG-Interferon lambda for inclusion in Phase 2b, namely 120 mcg, 180 mcg and 240 mcg.

The Phase 2b study will enroll approximately 600 patients with genotypes 1 - 4 chronic HCV infection. The study will assess the safety and antiviral efficacy of the three specified doses of PEG-Interferon lambda compared to PEGASYS^®. Each cohort of approximately 150 patients will include at least 100 genotype 1 patients. Weekly subcutaneous doses of PEG-Interferon lambda or PEGASYS will be administered for 48 weeks in genotype 1 or 4 patients and for 24 weeks in genotype 2 or 3 patients. All patients will also receive daily ribavirin. The primary endpoint of the trial is the proportion of patients who achieve undetectable levels of HCV RNA after 12 weeks of therapy (complete Early Virological Response). Sustained virological response (SVR), defined as undetectable levels of HCV RNA 24 weeks after treatment, will also be assessed.