Study to Evaluate the Efficacy and Safety of ABT-450/Ritonavir/ABT-267 (ABT-450/r/ABT-267) in Japanese Adults With Subgenotype 1b Chronic Hepatitis C Virus (HCV) Infection

The percentage noncirrhotic treatment-naïve participants who were eligible for IFN-based therapy and who had high viral load at baseline (HCV RNA ≥ 100,000 IU/mL) in the DB active treatment group with sustained virologic response (plasma Hepatitis C virus ribonucleic acid \[HCV RNA\] level less than the lower limit of quantitation \[\< LLOQ\]) 12 weeks after the last dose of active study drug (SVR12). Among noncirrhotic treatment-naïve participants who were eligible for IFN-based therapy and who had high viral load at baseline, superiority of Arm A to a clinically relevant threshold based on historical SVR rate with telaprevir plus pegylated interferon alpha/ribavirin (pegIFN/RBV) in treatment-naïve, non-cirrhotic patients with high viral load; the lower bound of 95% confidence interval (LCB) had to exceed 63% to achieve superiority. The 95% confidence interval was calculated using the normal approximation to the binomial distribution.

Time frame: 12 weeks after the last dose of study drug

Population: Primary Efficacy Population: randomized non-cirrhotic treatment-naïve participants who are eligible for interferon-based therapy and who have high viral load and received at least one dose of double-blind ABT-450/r/ABT-267.

Post-treatment relapse among all randomized non-cirrhotic participants who received at least one dose of DB ABT-450/r/ABT-267 and completed treatment, in the following subpopulations: noncirrhotic treatment-naïve (T-naïve) participants with a high baseline (BL) viral load (HCV RNA ≥ 100,000 IU/mL) who are eligible for IFN-based therapy (IFN-BT), a low BL viral load (HCV RNA \< 100,000 IU/mL), or who are ineligible for IFN-BT; noncirrhotic treatment-experienced (T-exp) participants who relapsed after prior IFN-BT, who were nonresponders to prior IFN-BT, or who were intolerant to IFN-BT. Relapse was defined as confirmed HCV RNA ≥ LLOQ (defined as 2 consecutive HCV RNA measurements ≥ LLOQ) between the final treatment visit and 12 weeks after the last dose of study drugs among participants completing treatment and with HCV RNA \< LLOQ at the final treatment visit and at least one post-treatment HCV RNA value. The 95% confidence interval was calculated using the Wilson's score method.

Time frame: within 12 weeks after last dose of study drug

Population: ITT population: all randomized/enrolled participants who received at least 1 dose of active DB study drugs in Substudy 1 (Substudy 1 ITT population, Arm A) and completed treatment; n=number of participants in the given subpopulation (among noncirrhotic participants, a single participant could potentially be included in more than 1 subpopulation).

Sustained virologic response (plasma HCV RNA level \< LLOQ) 12 weeks after the last dose of study drug for all randomized non-cirrhotic participants who received at least one dose of DB ABT-450/r/ABT-267 in the following subpopulations: noncirrhotic T-naïve participants with a high BL viral load (HCV RNA ≥ 100,000 IU/mL) who are eligible for IFN-BT; noncirrhotic T-naïve participants with low BL viral load (HCV RNA \< 100,000 IU/mL); noncirrhotic T-naïve participants who are ineligible for IFN-BT; noncirrhotic T-exp participants who relapsed after prior IFN-BT; noncirrhotic T-exp participants who were nonresponders to prior IFN-BT; noncirrhotic T-exp participants who were intolerant to IFN-BT. The 95% confidence interval was calculated using the Wilson's score method.

Time frame: 12 weeks after last dose of study drug

Population: ITT population: all randomized/enrolled participants who received at least 1 dose of active DB study drugs in Substudy 1 (Substudy 1 ITT population, Arm A); n=number of participants in the given subpopulation (among noncirrhotic participants, a single participant could potentially be included in more than 1 subpopulation).

On-treatment virologic failure among all randomized non-cirrhotic participants who received at least one dose of DB ABT-450/r/ABT-267 and all enrolled participants with compensated cirrhosis who received at least one dose of OL ABT-450/r/ABT-267. On-treatment virologic failure is defined as the occurrence of at least one of the following: * confirmed HCV RNA ≥ LLOQ (defined as 2 consecutive HCV RNA measurements ≥ LLOQ) at any point during treatment after HCV RNA \< LLOQ (rebound), or * confirmed increase from nadir in HCV RNA (defined as 2 consecutive HCV RNA measurements \> 1 log10 IU/mL above nadir) at any time point during treatment (rebound), or * HCV RNA ≥ LLOQ persistently during treatment with at least 6 weeks (≥ 36 days) of treatment (failure to suppress). The 95% confidence interval was calculated using the Wilson's score method.

Time frame: up to 12 weeks

Population: Intent-to-treat (ITT) population: randomized/enrolled participants who received at least 1 dose of DB study drugs in Substudy 1 (Substudy 1 ITT population) and completed treatment; n=number of participants in the given subpopulation (among noncirrhotic participants, a single participant could potentially be included in more than 1 subpopulation).

Post-treatment relapse among all randomized non-cirrhotic participants who received at least one dose of DB ABT-450/r/ABT-267 and completed treatment, and all enrolled participants with compensated cirrhosis who received at least one dose of OL ABT-450/r/ABT-267 and completed treatment. Relapse was defined as confirmed HCV RNA ≥ LLOQ (defined as 2 consecutive HCV RNA measurements ≥ LLOQ) between the final treatment visit and 12 weeks after the last dose of study drugs among participants completing treatment and with HCV RNA \< LLOQ at the final treatment visit and at least one post-treatment HCV RNA value. The 95% confidence interval was calculated using the Wilson's score method.

Time frame: within 12 weeks after last dose of study drug

Population: ITT population: all randomized/enrolled participants who received at least 1 dose of active DB study drugs in Substudy 1 (Substudy 1 ITT population, Arm A) or at least 1 dose of OL study drugs in Substudy 2 (Substudy 2 ITT population).

Sustained virologic response (plasma HCV RNA level \< LLOQ) 12 weeks after the last dose of study drug for all randomized non-cirrhotic participants who received at least one dose of DB ABT-450/r/ABT-267 and for all enrolled participants with compensated cirrhosis who received at least one dose of open-label ABT-450/r/ABT-267. The 95% confidence interval was calculated using the Wilson's score method.

Time frame: 12 weeks after last dose of study drug

Population: ITT population: all randomized/enrolled participants who received at least 1 dose of DB study drugs in Substudy 1 (Substudy 1 ITT population) or at least 1 dose of OL study drugs in Substudy 2 (Substudy 2 ITT population).

On-treatment virologic failure among all randomized non-cirrhotic participants who received at least one dose of DB ABT-450/r/ABT-267 in the following subpopulations: noncirrhotic treatment-naïve (T-naïve) participants with a high baseline (BL) viral load (HCV RNA ≥ 100,000 IU/mL) who are eligible for IFN-based therapy (IFN-BT), a low viral load (HCV RNA \< 100,000 IU/mL), or who are ineligible for IFN-BT; noncirrhotic treatment-experienced (T-exp) participants who relapsed after prior IFN-BT, who were nonresponders to prior IFN-BT, or who were intolerant to IFN-BT. On-treatment virologic failure is defined in Outcome measure 2. The 95% confidence interval was calculated using the Wilson's score method.

Time frame: up to 12 weeks

Population: ITT population: all randomized/enrolled participants who received at least 1 dose of active DB study drugs in Substudy 1 (Substudy 1 ITT population, Arm A).