Results of Boehringer Ingelheim's BI 201335 study presented at Annual Meeting of EASL

New data presented today at the 46th Annual Meeting of the European Association for the Study of the Liver (EASL) demonstrate the antiviral activity of Boehringer Ingelheim's once-daily oral protease inhibitor, BI 201335, in both treatment-naive and -experienced patients with chronic genotype-1 (GT1) hepatitis C virus (HCV), the most challenging genotype of HCV to treat.  Results from SILEN-C1 show a sustained viral response (SVR) in 71 to 83 percent of treatment-naive patients who received BI 201335 once-daily plus the current standard-of-care (SOC) [pegylated interferon (PegIFN) and ribavirin (RBV)].

Results from SILEN-C2 show an SVR in 28 to 41 percent of treatment-experienced patients who received BI 201335 once-daily plus PegIFN and RBV.

"SILEN-C1 and 2 have shown positive Phase 2 results in a broad range of HCV patients," said Peter Piliero, M.D., executive director, Medical Affairs, Boehringer Ingelheim Pharmaceuticals, Inc. "The current standard-of-care in HCV is not effective for enough patients. Protease inhibitors such as BI 201335 represent potential new options to improve outcomes and the possibility to shorten the duration of treatment for HCV disease."

"Boehringer Ingelheim is continuing its long heritage in virology and commitment to develop new medicines for HCV," continued Piliero. "BI 201335 is part of BI's growing HCV portfolio, which is being investigated with the goal of improving treatment and cure rates for HCV patients.  We are excited that we will commence our Phase 3 trial program with BI 201335 in the near future, based on the results of these Phase 2 studies."

(Oral abstract #60) SILEN-C1: Sustained Virologic Response (SVR) and Safety of BI 201335 Combined with Peginterferon Alfa-2a and Ribavirin in Treatment-Naive Patients with Chronic Genotype-1 HCV Infection

In this double-blind, randomized, placebo-controlled trial, 429 treatment-naive genotype-1 (GT-1) HCV patients were randomized (1:1:2:2) to receive either:

• Placebo plus PegIFN/RBV;
• BI 201335 120mg once-daily (QD) with a three-day LI of PegIFN/RBV;
• BI 201335 240mg QD with a three-day LI of PegIFN/RBV; or
• BI 201335 240mg QD plus PegIFN/RBV without LI

Patients were given BI 201335 for 24 weeks in combination with PegIFN/RBV, which was given for 24 or 48 weeks. Patients in the two BI 201335 240mg QD groups who achieved extended rapid virological response (eRVR, defined as plasma viral load less than 25 IU/ml at Week four and undetectable at Weeks 8-20), were re-randomized to discontinue PegIFN/RBV at Week 24 or continue PegIFN/RBV to Week 48.

Overall SVR rates reached 83 percent in the 240mg QD group (plus current SOC). A three-day lead in with SOC prior to initiation of BI 201335 was seen to reduce responses by 12 percent and 10 percent in 120mg QD/LI and 240mg QD/LI patient groups.  The LI was also associated with higher rates of viral breakthrough.  Of the patients in the 240mg QD dose group who achieved extended rapid viral response (eRVR, defined as plasma viral load less than 25 IU/ml at Week four and Weeks 8-20) and were re-randomized at Week 24, 93 percent achieved SVR with 24 weeks of SOC (PegIFN/RBV) treatment.  

The most frequent dose-dependent adverse events (AEs) in BI 201335 treatment groups were gastrointestinal disorders, rash or photosensitivity, and jaundice resulting from isolated unconjugated hyperbilirubinemia.  Average alanine aminotransferase (ALT) improved in all BI 201335 groups compared to placebo, and there was no excess anemia reported in the study.  Across BI 201335 treatment groups, 4 to 12 percent of patients discontinued BI 201335 due to AEs.  

(Oral abstract #66) SILEN-C2: Sustained Virologic Response and Safety of BI 201335 Combined with Peginterferon Alfa-2a and Ribavirin in Chronic HCV Genotype-1 Patients with Non-Response to PegIFN/RBV

The SILEN-C2 study evaluated the virological response and safety of different doses of BI 201335 in treatment-experienced patients who did not respond to at least 12 weeks of prior treatment with PegIFN/RBV. This patient population is particularly difficult to treat, as patients who have not responded to PegIFN/RBV alone have low response rates to additional treatments. The trial did not include patients who relapsed after initial treatment with PegIFN/RBV.

In this double-blind, randomized, placebo-controlled trial, 288 treatment-experienced GT-1 HCV patients were randomized (2:1:1) to receive either:

• BI 201335 240mg QD with a three-day LI of PegIFN/RBV;
• BI 201335 240mg QD plus PegIFN/RBV without LI; or
• BI 201335 240mg twice-daily (BID) with a three-day LI of PegIFN/RBV

In each group, patients were given BI 201335 for 24 weeks in combination with PegIFN/RBV, which was given for 24 or 48 weeks.

Patients in the two BI 201335 QD groups who achieved eRVR were re-randomized to either stop all treatment at Week 24 or continue PegIFN/RBV until Week 48.

BI 201335 once-daily at 240mg plus SOC provided positive Phase 2 results in this very difficult-to-treat patient population. As is seen in SILEN-C1, a three-day LI with SOC was associated with decreased viral response. Phase 3 trials of BI 201335 are in preparation.

The most frequent dose-dependent AEs in BI 201335 treatment groups were gastrointestinal disorders, jaundice resulting from unconjugated hyperbilirubinemia, and mild to moderate rash or photosensitivity. Serious or severe AEs were reported more frequently in the BI 201335 240mg BID with LI group. Discontinuations due to adverse events ranged from 4 percent in the BI 201335 240mg QD without LI group to 23 percent in the BI 201335 240mg BID with LI group.

Additional HCV Studies to be Presented at EASL

• SVR and pharmacokinetics of the HCV protease inhibitor BI 201335 with PegIFN/RBV in HCV genotype-1 patients with compensated liver cirrhosis and non-response to previous PegIFN/RBV
  (Poster #1231. S. Pol, et al., April 2, 9:00 a.m.-6:00 p.m. CET)
• Mechanisms of isolated unconjugated hyperbilirubinemia induced by the HCV NS3/4A protease inhibitor BI 201335
  (Poster #1236. R. Sane, et al., April 2, 9:00 a.m.-6:00 p.m. CET)
• BI 201335 pharmacokinetics and early effect on viral load in HCV genotype-1 patients
  (Poster #1249. C. Yong, et al., April 2, 9:00 a.m.-6:00 p.m. CET)
• Preclinical characterization of the hepatitis C virus NS5B polymerase non-nucleoside inhibitor BILB 1941
  (Poster #1215. G. Kukolj, et al., April 2, 9:00 a.m.-6:00 p.m. CET)