Nathalie Adda

Telaprevir for Previously Untreated Chronic Hepatitis C Virus Infection

BACKGROUND In phase 2 trials, telaprevir, a hepatitis C virus (HCV) genotype 1 protease inhibitor, in combination with peginterferon-ribavirin, as compared with peginterferon-ribavirin alone, has shown improved efficacy, with potential for shortening the duration of treatment in a majority of patients. METHODS In this international, phase 3, randomized, double-blind, placebo-controlled trial, we assigned 1088 patients with HCV genotype 1 infection who had not received previous treatment for the infection to one of three groups: a group receiving telaprevir combined with peginterferon alfa-2a and ribavirin for 12 weeks (T12PR group), followed by peginterferon-ribavirin alone for 12 weeks if HCV RNA was undetectable at weeks 4 and 12 or for 36 weeks if HCV RNA was detectable at either time point; a group receiving telaprevir with peginterferon-ribavirin for 8 weeks and placebo with peginterferon-ribavirin for 4 weeks (T8PR group), followed by 12 or 36 weeks of peginterferon-ribavirin on the basis of the same HCV RNA criteria; or a group receiving placebo with peginterferon-ribavirin for 12 weeks, followed by 36 weeks of peginterferon-ribavirin (PR group). The primary end point was the proportion of patients who had undetectable plasma HCV RNA 24 weeks after the last planned dose of study treatment (sustained virologic response). RESULTS Significantly more patients in the T12PR or T8PR group than in the PR group had a sustained virologic response (75% and 69%, respectively, vs. 44%; P<0.001 for the comparison of the T12PR or T8PR group with the PR group). A total of 58% of the patients treated with telaprevir were eligible to receive 24 weeks of total treatment. Anemia, gastrointestinal side effects, and skin rashes occurred at a higher incidence among patients receiving telaprevir than among those receiving peginterferon-ribavirin alone. The overall rate of discontinuation of the treatment regimen owing to adverse events was 10% in the T12PR and T8PR groups and 7% in the PR group. CONCLUSIONS Telaprevir with peginterferon-ribavirin, as compared with peginterferon-ribavirin alone, was associated with significantly improved rates of sustained virologic response in patients with HCV genotype 1 infection who had not received previous treatment, with only 24 weeks of therapy administered in the majority of patients. (Funded by Vertex Pharmaceuticals and Tibotec; ADVANCE ClinicalTrials.gov number, NCT00627926.).

Response-Guided Telaprevir Combination Treatment for Hepatitis C Virus Infection

BACKGROUND Patients with chronic infection with hepatitis C virus (HCV) genotype 1 often need 48 weeks of peginterferon-ribavirin treatment for a sustained virologic response. We designed a noninferiority trial (noninferiority margin, -10.5%) to compare rates of sustained virologic response among patients receiving two treatment durations. METHODS We enrolled patients with chronic infection with HCV genotype 1 who had not previously received treatment. All patients received telaprevir at a dose of 750 mg every 8 hours, peginterferon alfa-2a at a dose of 180 μg per week, and ribavirin at a dose of 1000 to 1200 mg per day, for 12 weeks (T12PR12), followed by peginterferon-ribavirin. Patients who had an extended rapid virologic response (undetectable HCV RNA levels at weeks 4 and 12) were randomly assigned after week 20 to receive the dual therapy for 4 more weeks (T12PR24) or 28 more weeks (T12PR48). Patients without an extended rapid virologic response were assigned to T12PR48. RESULTS Of the 540 patients, a total of 352 (65%) had an extended rapid virologic response. The overall rate of sustained virologic response was 72%. Among the 322 patients with an extended rapid virologic response who were randomly assigned to a study group, 149 (92%) in the T12PR24 group and 140 (88%) in the T12PR48 group had a sustained virologic response (absolute difference, 4 percentage points; 95% confidence interval, -2 to 11), establishing noninferiority. Adverse events included rash (in 37% of patients, severe in 5%) and anemia (in 39%, severe in 6%). Discontinuation of all the study drugs was based on adverse events in 18% of patients overall, as well as in 1% of patients (all of whom were randomly assigned) in the T12PR24 group and 12% of the patients randomly assigned to the T12PR48 group (P<0.001). CONCLUSIONS In this study, among patients with chronic HCV infection who had not received treatment previously, a regimen of peginterferon-ribavirin for 24 weeks, with telaprevir for the first 12 weeks, was noninferior to the same regimen for 48 weeks in patients with undetectable HCV RNA at weeks 4 and 12, with an extended rapid virologic response achieved in nearly two thirds of patients. (Funded by Vertex Pharmaceuticals and Tibotec; ILLUMINATE ClinicalTrials.gov number, NCT00758043.).

Telaprevir for Previously Treated Chronic HCV Infection

BACKGROUND Patients with genotype 1 hepatitis C virus (HCV) who do not have a sustained response to therapy with peginterferon alfa and ribavirin have a low likelihood of success with retreatment. METHODS We randomly assigned patients with HCV genotype 1 who had not had a sustained virologic response after peginterferon alfa-ribavirin therapy to one of four treatment groups: 115 patients to the T12PR24 group, receiving telaprevir (1125-mg loading dose, then 750 mg every 8 hours) for 12 weeks and peginterferon alfa-2a (180 microg per week) and ribavirin (1000 or 1200 mg per day, according to body weight) for 24 weeks; 113 patients to the T24PR48 group, receiving telaprevir for 24 weeks and peginterferon alfa-2a and ribavirin for 48 weeks (at the same doses as in the T12PR24 group); 111 patients to the T24P24 group, receiving telaprevir and peginterferon alfa-2a for 24 weeks (at the same doses as in the T12PR24 group); and 114 patients to the PR48 (or control) group, receiving peginterferon alfa-2a and ribavirin for 48 weeks (at the same doses as in the T12PR24 group). The primary end point was sustained virologic response (undetectable HCV RNA levels 24 weeks after the last dose of study drugs). RESULTS The rates of sustained virologic response in the three telaprevir groups--51% in the T12PR24 group, 53% in the T24PR48 group, and 24% in the T24P24 group--were significantly higher than the rate in the control group (14%; P<0.001, P<0.001, and P=0.02, respectively). Response rates were higher among patients who had previously had relapses than among nonresponders. One of the most common adverse events in the telaprevir groups was rash (overall, occurring in 51% of patients, with severe rash in 5%). Discontinuation of study drugs because of adverse events was more frequent in the telaprevir groups than in the control group (15% vs. 4%). CONCLUSIONS In HCV-infected patients in whom initial peginterferon alfa and ribavirin treatment failed, retreatment with telaprevir in combination with peginterferon alfa-2a and ribavirin was more effective than retreatment with peginterferon alfa-2a and ribavirin alone. (ClinicalTrials.gov number, NCT00420784.)

Evolution of Treatment-Emergent Resistant Variants in Telaprevir Phase 3 Clinical Trials

BACKGROUND Telaprevir (TVR), a hepatitis C virus (HCV) NS3/4A protease inhibitor, has been approved to treat genotype 1 HCV. To understand the clinical impact of TVR-resistant variants, we analyzed samples from patients in phase 3 clinical trials to determine the frequency and retention of TVR-resistant variants in patients who did not achieve sustained virologic response (SVR). METHODS A total of 1797 patients were treated with TVR. Resistant variants (V36A/G/I/L/M, T54A/S, I132V [subtype 1a only], R155G/K/T/M, A156F/N/S/T/V, and D168N) were identified after treatment failure and at visits thereafter, by direct (population) sequencing of the NS3/4A region. Kaplan-Meier analysis was used to determine median time to loss of these variants. RESULTS Resistant variants were observed in 77% (299/388) of patients who did not achieve SVR. Resistance occurred more commonly in subtype 1a (86%; 232/269) than subtype 1b infections (56%; 67/119). After treatment failure, 355 patients had at least 1 follow-up visit (median follow-up period: 9.6 months). Of patients with resistance at time of failure and at least 1 follow-up visit, 60% (153/254) lost resistance. Kaplan-Meier analysis, including all patients with any sequence data after treatment failure, indicated that median time to wild type was 10.6 months (95% confidence interval [CI], 9.47-12.20) in subtype 1a and 0.9 months (95% CI, 0.00-2.07) in subtype 1b infections. CONCLUSIONS After failure to achieve SVR with TVR-based treatment, resistant variants are observed in most patients. However, presumably due to the lower fitness of those variants, they tend to be replaced with wild-type virus over time.

Hepatitis C Viral Evolution in Genotype 1 Treatment-Naïve and Treatment-Experienced Patients Receiving Telaprevir-Based Therapy in Clinical Trials

Background In patients with genotype 1 chronic hepatitis C infection, telaprevir (TVR) in combination with peginterferon and ribavirin (PR) significantly increased sustained virologic response (SVR) rates compared with PR alone. However, genotypic changes could be observed in TVR-treated patients who did not achieve an SVR. Methods Population sequence analysis of the NS3•4A region was performed in patients who did not achieve SVR with TVR-based treatment. Results Resistant variants were observed after treatment with a telaprevir-based regimen in 12% of treatment-naïve patients (ADVANCE; T12PR arm), 6% of prior relapsers, 24% of prior partial responders, and 51% of prior null responder patients (REALIZE, T12PR48 arms). NS3 protease variants V36M, R155K, and V36M+R155K emerged frequently in patients with genotype 1a and V36A, T54A, and A156S/T in patients with genotype 1b. Lower-level resistance to telaprevir was conferred by V36A/M, T54A/S, R155K/T, and A156S variants; and higher-level resistance to telaprevir was conferred by A156T and V36M+R155K variants. Virologic failure during telaprevir treatment was more common in patients with genotype 1a and in prior PR nonresponder patients and was associated with higher-level telaprevir-resistant variants. Relapse was usually associated with wild-type or lower-level resistant variants. After treatment, viral populations were wild-type with a median time of 10 months for genotype 1a and 3 weeks for genotype 1b patients. Conclusions A consistent, subtype-dependent resistance profile was observed in patients who did not achieve an SVR with telaprevir-based treatment. The primary role of TVR is to inhibit wild-type virus and variants with lower-levels of resistance to telaprevir. The complementary role of PR is to clear any remaining telaprevir-resistant variants, especially higher-level telaprevir-resistant variants. Resistant variants are detectable in most patients who fail to achieve SVR, but their levels decline over time after treatment.

Retreatment with telaprevir combination therapy in hepatitis C patients with well-characterized prior treatment response†‡

Retreatment with peginterferon alpha and ribavirin (PR) offers a limited chance of sustained virologic response (SVR) in patients who did not achieve SVR with prior PR treatment. This study evaluated the safety and efficacy of telaprevir‐based treatment in combination with PR in well‐characterized patients who did not achieve SVR in the control arms of three Phase II clinical trials. Patients eligible to enroll in this open‐label nonrandomized study either met on‐treatment criteria for nonresponse or relapsed after 48 weeks of treatment in the control arm of the three Phase II PROVE studies. The initial protocol was a 24‐week regimen: 12 weeks of telaprevir and PR followed by an additional 12 weeks of PR. During the study the protocol was amended to extend PR to 48 weeks for patients with previous null response. All other patients with undetectable hepatitis C virus (HCV) RNA at weeks 4 and 12 received 24 weeks of therapy. Those with detectable HCV RNA at weeks 4 or 12 received a total of 48 weeks of therapy. The overall SVR rate was 59% (69/117). SVR rates with T12PR were 37% (19/51) in prior null responders, 55% (16/29) in prior partial responders, 75% (6/8) in prior breakthroughs, and 97% (28/29) in prior relapsers. The overall relapse rate was 16% (13/83). Adverse events were similar to those in previous trials with telaprevir, with 9% of patients discontinuing due to an adverse event (most commonly rash and anemia). Conclusion: This study demonstrated the benefit of retreatment with a telaprevir‐based regimen for patients with well‐characterized nonresponse (null and partial) or relapse to a prior course of PR treatment. (HEPATOLOGY 2011;)

The effect of CYP3A inhibitors and inducers on the pharmacokinetics of telaprevir in healthy volunteers.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

The Pharmacokinetic Interaction Between an Oral Contraceptive Containing Ethinyl Estradiol and Norethindrone and the HCV Protease Inhibitor Telaprevir

Background:Telaprevir is a hepatitis C virus protease inhibitor that is both a substrate and an inhibitor of CYP3A. Study Design:The effect of steady‐state telaprevir (administered 750 mg every 8 hours) on the steady‐state pharmacokinetics of ethinyl estradiol (EE) and norethindrone (NE) was evaluated in 24 healthy women receiving oral contraceptives (OC) containing 0.5 mg NE and 0.035 mg EE for at least 3 months at the time of screening. This was a phase 1, open‐label, single‐center, nonrandomized study that included a cycle 1 (OC only for 21 days, followed by no OC for 7 days), cycle 2 (OC plus telaprevir for 21 days, followed by telaprevir alone for 7 days), and a follow‐up period. Results:When administration with or without telaprevir was compared, the least‐squares mean ratios (90% confidence limits) for EE were 0.74 (0.68; 0.80) for Cmax, 0.67 (0.63; 0.71) for Cmin, and 0.72 (0.69; 0.75) for AUC; neither NE nor telaprevir exposure was affected. Conclusions:The efficacy of the OC may be compromised by the 26% to 33% reduction in EE exposure. Therefore, alternative methods of nonhormonal contraception should be used when hormonal contraceptives are coadministered with telaprevir and for up to 2 weeks following cessation of telaprevir.

Futility Rules for Telaprevir Combination Treatment for Patients With Hepatitis C Virus Infection

For patients treated with telaprevir, peginterferon, and ribavirin, futility rules have been developed to prevent needless drug exposure and minimize development of drug-resistant variants for patients who have little or no chance of achieving a sustained virologic response. We performed retrospective analyses of data from phase 3 trials and validated the current futility rule. All therapy should be stopped for treatment-naive and treatment-experienced patients if hepatitis C virus RNA levels are greater than 1000 IU/mL at weeks 4 or 12, or if hepatitis C virus RNA is detectable at week 24.

Modeling, Clinical and Virology Data From Phase 2 and 3 Studies Support 12-Week Telaprevir Duration in Combination With 24- or 48-Week Peginterferon/Ribavirin

assess the association of HBsAg loss with different clinical phases of HBV and coinfection with HCV or HDV. Method: A total of 3335 patients (2064 male, 1271 female; mean age: 39.5±12.8), who have been HBsAg positive for at least 1 year and those who followed up for at least 6 months are included in the study. HbsAg loss rates in different clinical phases and coinfection with HBV or HDV were assesed. Differences were determined by log-rank test. Results: Among this cohort; 1160 (34.7%) were inactive carriers, 1675 (50.2%) were chronic hepatitis B, 298 (8.8%) were HBV cirrhosis, 77 (2.3%) were chronic HDV hepatitis, 43 (1.2%) were compensated HDV cirhosis, 44 (1.31%) were co-infected with hepatitis B and C. HBsAg loss rates among different groups were depicted in Figure 1. During a mean follow-up period of median 198 week (range: 24–1306 week), annual Hbs Ag loss rates were 1.88% in HBV and HCV co-infection, 1.64% in inactive carriers, 1.14% in HBV cirrhosis, 0.52% in chronic hepatitis B, 0.64% in HDV. No difference of HBsAg loss was observed between compensated and decompensated cirrhosis. None of HDV cirrhotics had seroclearance. 58.5% of HBV and HCV coinfected, 59% of HDV infected, 20% of chronic hepatitis B patients who had loss of HBsAg were treated with interferon or pegylated interferon. Conclusion: Although HDV infection supresses HBV replication, it does not increase the HBsAg loss rates. However, co-infection with HCV increases the seroclerance rates. HBsAg loss was markedly higher among inactive carriers comparing to chronic hepatitis.