InterMune Announces Presentation of Clinical Data on Infergen Plus Ribavirin in Difficult to Treat HCV Patients

BOSTON -- InterMune, Inc. announced the presentation of clinical findings from three separate investigator-initiated studies of the use of Infergen® (interferon alfacon-1) in combination with ribavirin for the treatment of Hepatitis C (HCV) patients. The findings were presented at the 55th Annual Meeting of the American Association for the Study of Liver Diseases (AASLD) held in Boston.

These and other studies presented at this conference indicate a consistent pattern of efficacy and safety of Infergen in a number of important HCV clinical settings, stated Dan Welch, CEO and president of InterMune.  These data encourage our clinical research and commercial efforts in Infergen, our first entry into the HCV market.

Comparison of African American and Non African American Patient Sustained Virologic Response for PEG- IFN Alpha 2 + Weight-Based Ribavirin Nonresponders Retreated with IFN Alfacon-1 + Weight-Based Ribavirin

Carroll Leevy II, MD, director of clinical affairs at the New Jersey Medical Liver Center and Sammy Davis Jr. National Liver Center in Newark, New Jersey presented data evaluating the safety and efficacy of using daily Infergen in combination with ribavirin for the treatment of African American and non-African American patients who have failed to respond to pegylated interferon alpha-2 plus ribavirin therapy (PEG-nonresponders). Approximately 3.4 percent of African Americans living in the United States are infected with HCV, and African American patients treated with pegylated interferon alpha-2 plus ribavirin have historically exhibited considerably lower sustained virologic response (SVR) rates than non-African American patients. At time of enrollment, none of the 137 patients, 45 of whom were African American, had shown at least a 2 log drop in viral load following 12 weeks of first-line therapy with pegylated interferon alpha-2 and ribavirin. During the trial, patients were treated with daily Infergen plus ribavirin for 12 weeks and then with three times-per-week (tiw) Infergen plus ribavirin for an additional 36 weeks. A SVR of 27 percent (12/45) was achieved in the African American patient group. The SVR for all 137 patients was 37 percent (51/137). The most common adverse events were flu-like symptoms (fever, malaise, joint pains, and muscle aches) and fatigue. Sixteen percent (22/137) of patients required filgrastim for reductions in absolute neutrophils counts. In this study, African American and non-African American patients treated with Infergen plus ribavirin had a clinically significant rate of SVR.

Retreatment with Consensus Interferon and Ribavirin of HCV Patients with Non-Response or Relapse After Previous Alpha-Interferon Therapy

Wulf O. Boecher, MD, of University Hospital, Mainz, Germany presented results from a study which found that treatment with Infergen plus ribavirin induced SVR rates in a proportion of HCV nonresponders and patients who have relapsed after previous alpha-interferon therapy. The study included 95 patients with detectable HCV RNA after non-response or relapse to previous treatment with alpha-interferon (with or without ribavirin). These patients were assigned to one of two treatment arms to receive study treatment for a 48 week period. Arm 1 received daily Infergen at a steadily decreasing dosage for the first 24 weeks and then received tiw Infergen for the remaining 24 weeks.  Ribavirin was administered from weeks 3 through 48. Arm 2 received tiw Infergen at decreasing dosages plus ribavirin for 48 weeks. Nonresponders from arms 1 and 2 achieved SVR of 29 percent and 27 percent, respectively. Relapse patients treated in arms 1 and 2 achieved SVR of 75 percent and 41 percent, respectively. Therapy was discontinued in 7 percent and 6 percent of patients in arms 1 and 2 due to side effects, and interferon dose reductions were necessary in 26 percent and 6 percent of patients, respectively.

Antiviral Response of HCV Genotype-1 to Consensus Interferon and Ribavirin Compared with Pegylated Interferon and Ribavirin:  A Preliminary Report

Maria Sjogren, MD of the Walter Reed Army Medical Center presented data evaluating tiw Infergen plus ribavirin versus pegylated interferon alpha-2 plus ribavirin in naive patients. Results from a previously reported study by Dr. Sjogren that evaluated tiw Infergen plus ribavirin versus interferon alpha-2b plus ribavirin in 128 naive patients showed SVR of 57 percent for the Infergen treatment arm compared to 40 percent for the interferon alpha-2b arm. In the prospective, randomized clinical trial data presented this week at AASLD, 59 previously untreated patients with chronic genotype-1 HCV infection were administered either tiw Infergen or once a week pegylated interferon alpha-2.  Both groups were given ribavirin. Treatment will be administered for 48 weeks if blood levels of HCV RNA are undetectable at 24 weeks. Otherwise, the drugs will be discontinued. To date, 58 patients have received 24 weeks of therapy and the on-treatment response rate is equivalent in both groups; 52 percent of patients in each group had serum HCV RNA below the limit of detection.  Importantly, more dose modifications had to be made in the pegylated interferon alpha-2 group than in the Infergen group (57 percent vs. 34 percent). Common adverse events in both groups were flu-like symptoms in 100 percent and 89 percent, fatigue in 73 percent and 50 percent, headache in 63 percent and 39 percent, nausea in 27 percent and 24 percent, and mood disorders in 67 percent and 64 percent of the Infergen plus ribavirin and pegylated interferon alpha-2 plus ribavirin groups, respectively. Interim analysis of tiw Infergen plus ribavirin shows a comparable early virologic response to pegylated interferon alpha-2 plus ribavirin in naive patients. This Infergen regimen may prove more attractive in cost-conscious institutional settings.

About Chronic Hepatitis C

According to the Centers for Disease Control an estimated 3.9 million (1.8 percent) Americans have been infected with HCV, of whom 2.7 million are chronically infected. HCV causes an estimated 10,000 to 12,000 deaths annually in the United States and is the leading indication for liver transplant. The prevalence of chronic HCV is increasing. First-line treatment for patients chronically infected with HCV is pegylated interferon alfa-2 plus ribavirin.  Approximately half of all patients treated do not respond. There are approximately 150,000 PEG-nonresponders in the United States and the number is growing by an estimated 50,000 each year.

About Infergen® (interferon alfacon-1)

Infergen is a bio-optimized type 1 interferon alpha indicated for treatment of adult patients with chronic HCV infections with compensated liver disease and is dosed three times-per-week. Infergen is the only interferon alpha with data in the label regarding use in patients following relapse or non-response to certain previous treatments. The most common side effects are flu-like symptoms (i.e., headache, fatigue, fever, myalgia, and rigors).  Physicians and patients can obtain additional prescribing information regarding Infergen, including the products safety profile and the black box warning for all interferon alphas regarding neuropsychiatric, autoimmune, ischemic and infectious disorders, by visiting http://www.infergen.com.

InterMunes Commitment in Hepatology

InterMune is a biopharmaceutical company that is committed to developing and commercializing innovative therapies in hepatology. In addition to the currently marketed product indicated for the treatment of chronic HCV (Infergen®)InterMune has a broad and deep late-stage product portfolio addressing HCV, particularly in patients who are considered nonresponders to previous pegylated interferons plus ribavirin. Leading the hepatology portfolio is the DIRECT trial, an ongoing Phase III study of daily interferon alfacon-1 (Infergen®) plus ribavirin, and an ongoing Phase II trial of daily interferon alfacon-1 plus interferon gamma-1b (Actimmune®) with and without ribavirin. Both of these trials are for the treatment of HCV patients who do not respond to first-line therapy (pegylated interferon-alfa 2a or 2b plus ribavirin). In addition, InterMune has an early stage small molecule program targeted at the HCV protease.

Source: InterMune, Inc.