InterMune Announces Interim Data Showing High Early Virologic Response To Infergen in Peg-Interferon Non-Responders With Chronic Hepatitis C
Monday May 19, 5:51 pm ET
24-week Data Supports Potential Antiviral Efficacy, Tolerability In Difficult-to-Treat Patients
ORLANDO, Fla. and BRISBANE, Calif., May 19 /PRNewswire-FirstCall/ -- InterMune, Inc. (Nasdaq: ITMN - News) announced today that interim 24-week data showing high early virologic response rates in a clinical trial of daily dosing and induction dosing regimens of Infergen® (interferon alfacon-1) in chronic hepatitis C patients non-responsive to pegylated interferon and ribavirin combination therapy (non-responders) were presented at the Digestive Disease Week (DDW) 2003 conference in Orlando, Florida.
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Researchers reported the interim data showed that more than half (52%) of the non-responders subsequently responded to treatment, which included 27 micrograms daily interferon alfacon-1 monotherapy for 4 weeks, followed by 20 weeks of daily combination therapy with lower doses of interferon alfacon-1 plus ribavirin. The patients in the trial will continue on combination therapy for an additional 24 to 64 weeks.
"These interim data indicate the potential of interferon alfacon-1 to effectively clear the hepatitis C virus in these difficult-to-treat non- responders, who were predominantly patients with genotype 1 HCV and high viral load," said Dr. Stephan Kaiser of the University Hospital of Tubingen, Germany, lead principal investigator of the trial, who presented the data at DDW. "In addition, both the daily dosing and induction dosing regimens were moderately well tolerated. If the encouraging early antiviral response rates seen in this interim analysis translate into correspondingly strong sustained antiviral response rates, interferon alfacon-1 may become the foundation for optimal management of these non-responding patients."
"Over 50% of HCV patients fail standard-of-care treatment with pegylated interferons and ribavirin, and the growth of this patient population is expected to outpace that of treatment-naive, chronic hepatitis C patients by the end of the decade. Further, past clinical studies on the use of the combination of pegylated interferons and ribavirin for re-treatment of non-responders to standard-of-care treatment have demonstrated only limited therapeutic efficacy," said James E. Pennington, M.D., InterMune's Executive Vice President of Medical and Scientific Affairs. "These interim data, which corroborate previous studies showing interferon alfacon-1 provides a high antiviral response in difficult-to-treat non-responders, could be very important in helping to meet this growing unmet medical need and large market opportunity. Because the interim data show both high and early virologic response, it is our hope that these patients will attain a sustained virologic response."
Results Review
A randomized, open-label trial was conducted in 50 chronic hepatitis C patients who were non-responders to prior combination therapy with pegylated interferon and ribavirin. Two-thirds of the patients in the trial had failed treatment with pegylated interferon alpha-2b, and one-third of the patients had failed therapy with pegylated interferon alpha-2a. More than 90% of the patients in the trial were infected with HCV of genotype 1 or 4, which are the most difficult to treat genotypes. Over 70% of the patients in the trial had high baseline levels of HCV RNA (viral load > 8.5 X 10(5) IU).
Patients on the daily dosing regimen received 9 micrograms interferon alfacon-1 daily for 4 weeks, followed by a daily combination of 9 micrograms interferon alfacon-1 plus ribavirin for 20 weeks. Patients on the induction dosing regimen received 27 micrograms interferon alfacon-1 daily for 4 weeks, then a daily combination of 18 micrograms interferon alfacon-1 plus ribavirin for 12 weeks, followed by a daily combination of 9 micrograms interferon alfacon-1 plus ribavirin for the next 8 weeks. The patients in the trial will continue on combination therapy for an additional 24 to 64 weeks, depending on progress and whether they were assigned to the daily dosing or induction dosing regimen.
The efficacy endpoints for this trial include: (a) the effects of initial treatment with interferon alfacon-1 on the level of HCV RNA in serum; and (b) the ability of the combination of interferon alfacon-1 and ribavirin to render the level of HCV RNA in serum undetectable at 24 weeks after the cessation of therapy. Antiviral efficacy was evaluated by PCR measurement of concentrations of HCV RNA in serum. The interim analysis consisted of examination of HCV viral load at 8 and 24 weeks and evaluation of safety data.
At week 8, an antiviral response consisting of a negative PCR result (i.e., undetectable HCV RNA) in serum was observed in 20% (6/30) and 27% (8/30) of patients treated with the daily dosing and induction dosing regimen, respectively. At week 24, an antiviral response consisting of HCV RNA undetectable by PCR in serum samples was observed in 40% (10/25) and 52% (14/25) of patients treated with the daily dosing and induction dosing regimen, respectively.
Both the daily dosing and induction dosing regimens of interferon alfacon- 1 were found to be safe and moderately well tolerated. Adverse events were consistent with past experience in clinical trials and included myalgia, fatigue and headache. The laboratory abnormalities observed in the first 24 weeks of therapy were also consistent with those observed in past Infergen clinical trials, with no reports of grade 4 neutropenia and grade 3/4 thrombocytopenia reported in only one patient.
About Chronic Hepatitis C
Over 4 million individuals in the United States have been exposed to the hepatitis C virus. More than 200,000 patients in the United States are treated annually for hepatitis C infection. The prevalence of chronic hepatitis C, a serious disease, is increasing.
About Infergen (R) (interferon alfacon-1)
Infergen® is a bio-optimized type 1 interferon alpha indicated for treatment of adult patients with chronic HCV infections. Infergen® is the only interferon alpha with data in the label regarding use in patients following relapse or non-response to treatment with 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 product's safety profile, by visiting infergen.com, including the black box warning for all interferon alphas regarding psychiatric, autoimmune, ischemic and infectious disorders. |
