ABBOTT PARK, Ill. and WATERTOWN, Mass., April 19, 2012 /PRNewswire/ -- Abbott (NYSE: ABT) and Enanta Pharmaceuticals announced complete data from the study known as "Pilot" – Abbott's initial interferon-free study of its direct-acting antiviral agents for the treatment of hepatitis C (HCV) – showing that 91 percent of genotype 1 infected, treatment-naive patients taking ABT-450/r and ABT-072 combined with ribavirin administered for 12 weeks, achieved sustained viral response at 24 weeks (SVR24). 82 percent of patients achieved SVR36. This is among the first 12-week, interferon-free HCV regimen with 36-week post-treatment data in genotype 1 patients. Results were presented today at the International Liver Congress 2012 (ILC 2012), the annual meeting of the European Association for the Study of the Liver (EASL), April 18-22 in Barcelona, Spain.
"The sustained viral response rates in this study are very encouraging as there are currently no treatment options for patients with HCV who cannot take or are intolerant to interferon," said Eric Lawitz, M.D., medical director at Alamo Medical Research in San Antonio, and the lead investigator for the study. "This is one of the earliest looks at mature data and it continues to demonstrate that a 12-week combination regimen of direct-acting antiviral treatments has the potential to offer high cure rates while eliminating the use of interferon."
Current treatments for HCV remain interferon-based. A significant number of HCV patients are unable or unwilling to take interferon due to contraindications and/or side effects, which may include flu-like symptoms, depression and insomnia. Specifically targeted antiviral therapies for HCV, such as protease inhibitors and non-nucleoside polymerase inhibitors, may have the potential to increase the proportion of patients in whom the virus can be eradicated.
About Study M12-267 (Pilot) and Key Findings
- The objectives of the 12-week, Phase 2 study were to assess the safety, tolerability, pharmacokinetics and antiviral activity of ABT-450/r 150/100 mg QD and ABT-072 400 mg QD + ribavirin administered for 12 weeks.
- The study was conducted in 11 treatment-naive adults with host IL28B "CC" genotype from multiple ethnic backgrounds with non-cirrhotic HCV GT1 (8 GT 1a, 3 GT 1b). Ribavirin dose was weight-based (1,000-1,200 mg/day) and dosed twice daily.
- The primary endpoint was percentage of patients with HCV RNA <25 IU/mL from week 4 through 12. Other trial endpoints include early virologic response, RVR and SVR through 24 weeks.
- 100 percent of patients maintained HCV RNA levels <25 IU/mL from weeks 4 through 12 of treatment, and all had undetectable HCV RNA from week 5 to the end of treatment.
- 91 percent of patients (10 of 11) achieved SVR24.
- One relapse was observed 8 weeks post therapy and a second 36 weeks post therapy; overall, 82 percent of patients (9 of 11) achieved SVR36.
- No additional relapses were seen among the 10 patients with 48-week post-treatment data available / where SVR48 results were available.
- In the trial, the most common adverse events were headache (36%), fatigue (27%), nausea (27%) and dry skin (27%). Most adverse events were mild in severity and there were no discontinuations due to adverse events.
- Two bilirubin elevations, which consisted of indirect bilirubin with no associated transaminase elevations (i.e. no indication of liver damage), were reported during the study. The bilirubin elevations occurred one week after starting treatment and resolved with continued dosing.