Three Rivers Announces Positive Results from Phase 3 DIRECT Trial of Once-Daily Infergen with Ribavirin in Hepatitis C Virus Treatment Failures
WARRENDALE, Pa., June 16 /PRNewswire/ -- Three Rivers Pharmaceuticals announced today positive results of the U.S.-based, randomized Daily-Dose Consensus Interferon and Ribavirin: Efficacy of Combined Therapy (DIRECT) clinical trial authored by Bruce R. Bacon, M.D., of Saint Louis University, and colleagues at 44 centers in the United States. The primary endpoint of increased sustained virological response (SVR), was achieved demonstrating that INFERGEN provides a second chance to those HCV patients failing to respond to standard, first-line therapy of pegylated interferon (PEG-IFN) plus ribavirin (RBV). "The retreatment of PEG-IFN/RBV nonresponders with INFERGEN and RBV is safe and efficacious and can be considered a retreatment strategy for patients failing previous therapy with PEG-IFN/RBV, especially in interferon-sensitive patients with lower baseline fibrosis scores," stated Dr. Bruce Bacon the lead Investigator for the study.
Among participants who failed initial treatment with PEG-IFN/RBV, retreatment with INFERGEN in combination with RBV yielded SVR rates as high as 31.6 % in interferon-sensitive patients with low baseline liver fibrosis scores, the researchers reported in the June 2009 issue of Hepatology. Overall intent to treat analysis was 6.9% among the 9 mcg/day group and 10.7% in the 15 mcg/day group.
Defining viral response at Weeks 12 and 24 with INFERGEN and RBV in patients who were prior non-responders to PEG-IFN/RBV therapy can help predict SVR rates in this difficult-to-treat group of patients. All patients attaining SVR demonstrated > 2-log drop at Week 12 of INFERGEN/RBV therapy. Of significant note for these patients was the analysis regarding viral response at 12 weeks. In the DIRECT trial, 81.3% and 63.6% of patients achieving viral negativity at Week 12 went on to have an SVR in the 9 mcg and 15 mcg arms, respectively. In addition, slow responders achieved SVR rates of 11.7% and 35.4% in the 9 mcg and 15 mcg arms. Regardless of treatment dose used, attaining viral negativity at Week 12 or at Week 24 while on therapy with INFERGEN and RBV leads to a high sustained virological response rate.
"These results represent a significant step forward for HCV patients who deserve a second chance at a potential cure for this chronic viral infection" stated Donald Kerrish, President and CEO of Three Rivers Pharmaceuticals.
Approximately 50% of patients with chronic hepatitis C fail to respond to their initial course of PEG-IFN/RBV therapy. No standard has yet emerged for second-line therapy, since simply repeating the same treatment, in well controlled trials, has yielded low response rates around 2-6%.
The DIRECT trial was a phase 3, randomized, open-label, multicenter, U.S.-based trial conducted to investigate the efficacy, tolerability, and safety of daily INFERGEN at dosages of 9 and 15 mcg/day administered with daily weight-based RBV. The study tested 2 dosages of INFERGEN in 487 documented non-responders, of which 80% did not achieve a 2-log drop on prior pegylated-interferon plus ribavirin therapy. The best SVR rates were seen in:
-- Patients achieving the greatest reduction in baseline viral load with
peg-IFN/RBV therapy, especially in patients demonstrating > 1-log drop
with initial therapy
-- Patients with fibrosis scores of F0 to F3 at baseline demonstrated
SVRs of 7.8% in the 9 mcg arm and 13.1% in the 15 mcg arm
-- Patients maintaining full dose of INFERGEN/RBV therapy had SVRs of 7%
and 17% for the 9 mcg and 15 mcg arms respectively
-- Patients demonstrating partial response (>2-log drop) with previous
treatment and low fibrosis scores F0-F3 had SVRs of 10.7% and 31.6%
for the 9 mcg and 15 mcg arms
Patients with cirrhosis were less likely to benefit from retreatment with INFERGEN and RBV unless they displayed previous interferon sensitivity of at least 1-log drop in viral levels on prior therapy.
About Consensus Interferon (INFERGEN(R))
Consensus Interferon or INFERGEN(R) is a unique, bio-optimized, selective and highly potent type 1 interferon alpha. INFERGEN is indicated for the treatment of chronic HCV infection in patients 18 years of age or older with compensated liver disease who have anti-HCV serum antibodies and /or the presence of HCV RNA. INFERGEN is currently FDA approved for TIW monotherapy dosing in naive and previous treatment failure patients.
Important Safety Information
Physicians and patients can obtain additional prescribing information regarding INFERGEN, including the product's safety profile and the box warning for all interferon alphas regarding neuropsychiatric, autoimmune, ischemic and infectious disorders, by visiting www.infergen.com.
About Hepatitis C
Hepatitis means inflammation of the liver. Hepatitis C is a liver disease that results from infection with the hepatitis C virus. It can range in severity from a mild illness lasting a few weeks to a serious, lifelong illness. Hepatitis C can be either "acute" or "chronic." Acute hepatitis C virus infection is a short-term illness that occurs within the first 6 months after someone is exposed to the hepatitis C virus. For most people, acute infection leads to chronic infection. Chronic hepatitis C is a serious disease than can result in long-term health problems, or even death. There is no vaccine for hepatitis C.
About Three Rivers Pharmaceuticals
Three Rivers Pharmaceuticals is a privately held company headquartered in Warrendale, Pennsylvania that focuses on specialized therapies including hepatitis C therapies. More information about the company can be found at www.3riverspharma.com.
Source: Three Rivers Pharmaceuticals, LLC
CONTACT: Paul Fagan of Three Rivers Pharmaceuticals, +1-724-778-6007,
Web Site: http://www.3riverspharma.com
Posted: June 2009