The phase-2 trial you cited from Conatus Pharma has the oddest design of any HCV trial I’ve seen, notwithstanding the fact that it’s a second-line trial for first-line null responders.
No patients in the trial receive interferon, and the variable between the two trial arms is not the experimental drug, CTS-1027, as one might, but rather is ribavirin. I.e. one of the two trial arms is CTS-1027 monotherapy for 24 weeks!
That the FDA allowed this trial to be conducted shows an impressive (and somewhat surprising) willingness by the FDA to consider novel ideas in the second-line / null-responder setting. We previously saw an example of such thinking in the FDA’s granting permission for BMY to run an all-oral phase-2 trial in which neither individual drug had previously been tested in phase-2 (#msg-44700187).
›Conatus Pharmaceuticals Initiates Phase II Clinical Trial in Combination With Pegylated Interferon and Ribavirin for the Treatment of Hepatitis C Virus
Thursday January 28, 2010, 4:30 pm EST
SAN DIEGO, Jan. 28 /PRNewswire/ -- Conatus Pharmaceuticals Inc. announced today the initiation of a Phase II clinical trial evaluating CTS-1027 in combination with pegylated interferon (Pegasys®) and ribavirin (Copegus®) in refractory HCV patients. Antiviral activity, safety and tolerability of the triple combination will be assessed after up to 48 weeks of therapy.
"There is a significant unmet medical need in HCV patients who have not responded to pegylated interferon and ribavirin. These patients often progress to cirrhosis, a life-threatening condition. CTS-1027 has the potential to increase the effectiveness of the combination of pegylated interferon and ribavirin in this population," said Dr. Paul J. Pockros, Head, Division of Gastroenterology and Director of the SC Liver Research Consortium and The Scripps Clinic in La Jolla, CA.
CTS-1027 is an oral, small molecule compound that inhibits the activity of key members of a class of protease enzymes, the matrix metalloproteinases or MMPs. CTS-1027's anti-inflammatory and anti-fibrotic effects have been well-established in models of acute hepatitis and liver fibrosis. In addition, CTS-1027 has been shown to reduce and/or block HCV replication in in vitro preclinical models.
This clinical trial is an open-label design testing an optimized dose of CTS-1027 in combination with Pegasys® and Copegus® in HCV-infected patients who were prior null responders to pegylated interferon and ribavirin treatment. Dosing will last for up to 48 weeks. The Company expects approximately 60 patients to be enrolled. The clinical trial will be conducted at up to fifteen medical centers in the U.S. Additional information about the trial can be found at: www.clinicaltrials.gov (Identifier NCT01051921) or www.clinicaltrials.gov/ct2/show/NCT01051921 .
"Our studies suggest that CTS-1027 treatment has the potential to amplify the effectiveness of pegylated interferon and ribavirin therapy. We believe that treating the most refractory patients will give us the best indication as to whether CTS-1027 can enhance the activity of existing therapy," said Steven J. Mento, President and CEO of Conatus. "The field is moving towards combinations of small molecules, and CTS-1027 represents a novel approach that we hope will benefit patients infected with HCV."
Conatus Pharmaceuticals Inc. is a privately-held specialty pharmaceutical company engaged in the development of innovative human therapeutics to treat liver disease. Chronic liver disease affects millions of people worldwide and can be caused by many different conditions or "insults" to the liver including Hepatitis C and other viral infections, obesity, chronic alcohol abuse or autoimmune diseases. Conatus was founded by the executive management team of Idun Pharmaceuticals in July 2005 following the successful sale of Idun to Pfizer. For additional information, please visit www.conatuspharma.com.‹