BRISBANE, Calif., April 15 /PRNewswire-FirstCall/ -- InterMune, Inc. today announced results of all three cohorts from a 15-day Phase 1b multiple-ascending-dose (MAD) study of low doses of danoprevir (also known as RG7227 and ITMN-191) boosted by low-dose ritonavir (RTV) in patients chronically infected with hepatitis C virus (HCV) genotype-1. The results announced today were reported in an oral presentation at the 45th Annual Meeting of the European Association for the Study of the Liver (EASL) in Vienna, Austria by Edward Gane, M.D., Associate Professor, University of Auckland, and Director, Auckland Clinical Studies Limited.
Dr. Gane commented, “The results from this study indicate that robust viral kinetics in treatment- naive patients can be achieved by ritonavir boosting of very low doses of danoprevir. We look forward to the results of the two 12-week cohorts in prior SOC null responders recently added to this study which will provide further insights into the antiviral efficacy and safety profile of low doses of ritonavir-boosted danoprevir.”
Viral Kinetic and Pharmacokinetic Performance of Ritonavir-Boosted Danoprevir
The Phase 1b study examined three dosage cohorts of danoprevir to date: 100 mg twice daily, 200 mg once daily, and 200 mg twice daily. Each was administered for 15 days in combination with 100 mg ritonavir on the same schedule, and with standard-dose PEGASYS and COPEGUS, the current standard of care (SOC).
A 200 mg once-daily dose of danoprevir with a 100 mg once-daily dose of ritonavir resulted in 63% of patients with HCV RNA levels below LLOQ (5 out of 8 patients total) and 50% of patients with HCV RNA levels below LLOD (4 patients out of 8 patients total) after only 15 days. At the highest daily dose, 200 mg twice-daily danoprevir in combination with 100 mg twice-daily ritonavir, 100% of patients achieved HCV RNA below LLOQ and LLOD (8 out of 8 patients total) after 15 days.
The pharmacokinetic profile of ritonavir-boosted danoprevir was more favorable than that observed in previously reported studies conducted with much higher doses of un-boosted danoprevir. At 100 mg danoprevir dosed twice daily with 100 mg ritonavir, AUC and Cmax were approximately 16-fold and 23-fold lower, respectively, than that provided by 900 mg twice-daily un-boosted danoprevir (historical Phase 1 and 2 data).
Amended Protocol - 12 Weeks of RTV-boosted Danoprevir
The companies reported that the Phase 1b MAD ritonavir-boosting study protocol has been amended to add two cohorts which will examine 12 weeks of low doses of ritonavir-boosted danoprevir plus SOC in prior SOC null responders. The doses to be examined in the expanded protocol are 100 mg twice daily and 200 mg once daily, each in combination with 100 mg ritonavir on the same schedule, plus the standard dose and regimen of SOC. The first patient in the amended protocol was enrolled in late March 2010.
About Danoprevir (RG7227/ITMN-191)
Danoprevir (also known as RG7227 and ITMN-191) is a potent, macrocyclic inhibitor of HCV NS3/4A protease activity being developed in collaboration with Roche. The safety and antiviral activity of danoprevir is expected to be further evaluated in a Phase 2b study of danoprevir in combination with low doses of ritonavir and the current standard of care, and is also under clinical investigation in combination with the NS5B nucleoside polymerase inhibitor RG7128 in the INFORM clinical development program.
Forward-Looking Statements
Factors that could cause or contribute to such differences include, but are not limited to, those discussed in detail under the heading “Risk Factors” in InterMune’s most recent annual report on Form 10-K filed with the SEC on March 15, 2010 (the “Form 10-K”) and other periodic reports filed with the SEC, including the following: (i) risks related to the long, expensive and uncertain clinical development and regulatory process, including having no unexpected safety, toxicology, clinical or other issues or delays in anticipated timing of the regulatory approval process; (ii) risks related to failure to achieve the clinical trial results required to commercialize our product candidates; and (iii) risks related to timely patient enrollment and retention in clinical trials. The risks and other factors discussed above should be considered only in connection with the fully discussed risks and other factors discussed in detail in the Form 10-K and InterMune’s other periodic reports filed with the SEC, all of which are available via InterMune’s web site at www.intermune.com.
CONTACT: Jim Goff of InterMune, Inc., +1-415-466-2228, jgoff@intermune.com
Web site: http://www.intermune.com/
