HUDDINGE, Sweden, May 20, 2011 /PRNewswire/ -- Medivir AB (OMX: MVIR), the emerging research-based specialty pharmaceutical company focused on infectious diseases, today announced results from the ASPIRE phase 2b study that evaluates the addition of once daily TMC435 to pegylated interferon and ribavirin in patients with genotype 1 chronic hepatitis C whose prior treatment with pegylated-interferon (PegIFN) and ribavirin (RBV) was unsuccessful either because they relapsed, had a partial response or had a null response.

Bertil Samuelsson, CSO of Medivir, commented, "We are delighted with the encouraging efficacy and safety results shown by TMC435-based triple therapy over pegylated-interferon and ribavirin, in this 48-Week interim analysis of the ASPIRE study in treatment experienced genotype-1 hepatitis C patients. This patient group is known to be the most difficult one to treat, where in particular prior null and partial responder groups respond very poorly upon retreatment with PegIFN/RBV alone. With several global phase 3 clinical trials ongoing in hepatitis C patients we are expecting the momentum to continue with regards to the development of TMC435."

ASPIRE (C206) - Design and Week-48 Interim Analysis

TMC435, a potent, once-daily, oral hepatitis C virus protease inhibitor is being developed by Tibotec jointly with Medivir. The randomized, placebo-controlled, double-blind ASPIRE study evaluates the effect of TMC435 in combination with pegylated-interferon and ribavirin in 462 patients infected with genotype-1 hepatitis C virus who have failed prior treatment with PegIFN/RBV. The study includes patients that have relapsed, achieved partial response, or achieved no response (null responders) to SoC treatment and where 62 percent (287/462) of patients overall had advanced liver disease, periportal or septal fibrosis or cirrhosis (scarring of the liver) upon study entry (Metavir score F2-F4).

Patients were equally randomized to 1 of 7 different treatment arms: 6 TMC435 treatment arms and one placebo arm. TMC435 was administered once daily at a dose of either 100 mg or 150 mg given for either 12, 24, or 48 weeks in combination with PegIFN/RBV. PegIFN/RBV treatment was continued in all patients until the study completion at week 48. This interim analysis was performed when all patients had completed 48 weeks of treatment or discontinued earlier. The analysis was done based on the intent-to-treat, ITT, population which included all randomized subjects who took at least one dose of the study medication. SVR4, Sustained Virologic Response 4 weeks after planned end of treatment data, was available for 94% and 84% of TMC435 and placebo patients respectively.

ASPIRE Results - Efficacy

In this Week 48 interim analysis, all subgroups of treatment-experienced patients who failed previous peginterferon and ribavirin treatment, achieved substantially higher virologic response rates following treatment with TMC435-containing regimen at all doses and durations, compared with pegylated-interferon and ribavirin.

There was no relevant difference in virological response between the TMC435 150 mg dose groups who received TMC435-based triple therapy of 12 weeks, 24 weeks or 48 weeks. At end of treatment (EoT) 92%, 83% and 71% of relapser patients, partial responder patients and null responder patients taking TMC435 150 mg once daily and placebo, respectively, achieved undetectable HCV RNA levels compared to 70%, 17% and 25% in the placebo PegIFN/RBV groups respectively. At week 4 after cessation of treatment (SVR4) 88%, 77% and 57% of prior relapser patients, partial responder patients and null responder patients taking TMC435 150 mg once daily and placebo, respectively, achieved undetectable HCV RNA levels, compared to 50%, 11% and 23% in the placebo groups, respectively.

Virological Response Rates in TMC435 Dose Groups (150 mg q.d.) vs Placebo TMC435 TMC435 TMC435 All TMC435 Placebo % (n/N) 12PR48 24PR48 48PR48 PR48 PR48 N=66 N=68 N=65 N=199 N=66 Prior EoT 92 (24/26) 93 (25/27) 92 (24/26) 92 (73/79) 70 (19/27) Relapser SVR4 84 (21/25) 93 (25/27) 85 (22/26) 87 (68/78) 50 (12/24) Prior EoT 78 (18/23) 83 (20/24) 86 (19/22) 83 (57/69) 17 (4/23) Partial Responder SVR4 64 (14/22) 86 (18/21) 82 (18/22) 77 (50/65) 11 (2/18) Prior Null EoT 65 (11/17) 71 (12/17) 77 (13/17) 71 (36/51) 25 (4/16) Responder SVR4 56 (9/16) 60 (9/15) 56 (9/16) 57 (27/47) 23 (3/13)

q.d.: once daily; PR: pegIFNalpha-2A and ribavirin; EoT: End of Treatment,

SVR4: patients with undetectable HCV RNA (<25 IU/mL Undetectable) at EOT and 4 weeks after planned EoT. Prior Relapser: undetectable HCV RNA at EoT and detectable within 24 weeks of follow-up

Partial Responders: more than 2 log reduction in HCV RNA at W12 but not achieving undetectable at EoT

Prior Null Responders: less than 2 log reduction in HCV RNA at W12

Results - Safety and Tolerability

TMC435 was generally safe and well tolerated and overall incidence of adverse events (AEs) was similar across treatment groups. Most of the AEs were grade 1 or 2 in severity. Serious AEs (SAEs) were reported in 6.1% subjects in the placebo and in 8.3% of the subjects treated with TMC435 with no substantial differences seen between the TMC435 dose groups. AEs leading to treatment discontinuation were reported in 4.5% of the placebo subjects and in 8.8% of the TMC435 treated subjects. Patients in the TMC435 ASPIRE treatment groups had overall longer treatment duration than patients in the placebo group due to a higher frequency of early discontinuation in the placebo group caused by treatment failures (i.e. reaching viral stopping rules). The most common AEs during the treatment period were headache, fatigue, pruritus and influenza-like illness. Incidence was similar across treatment groups and the level of AEs and frequency were consistent with prior phase 2b PILLAR study of TMC435.

In the safety analyses, special attention was given to the following AEs of interest: hepatobiliary AEs, pruritus, rash, anemia and cardiac events. Most AEs of interest were grade 1 or 2 in severity and infrequently led to treatment discontinuation. For each category of AEs of interest the incidence was similar with TMC435 and PegIFN/RBV.

Mild and reversible increases in bilirubin (total, direct and indirect) were observed in TMC435 dose groups with no differences between 100 mg and 150 mg. There were no meaningful differences between treatment groups for any of the other laboratory parameters. There were no clinically significant findings on vital signs, nor were there any relevant changes in electrocardiogram (ECG) parameters, including QTc. Mean alanine aminotransferase (ALT) levels decreased in all treatment groups.