Chih-Wei Lin

Glecaprevir plus pibrentasvir for chronic hepatitis C virus genotype 1, 2, 4, 5, or 6 infection in adults with compensated cirrhosis (EXPEDITION-1): a single-arm, open-label, multicentre phase 3 trial

BACKGROUND The once-daily, ribavirin-free, pangenotypic, direct-acting antiviral regimen, glecaprevir coformulated with pibrentasvir, has shown high rates of sustained virological response in phase 2 and 3 studies. We aimed to assess the efficacy and safety of 12 weeks of coformulated glecaprevir and pibrentasvir in patients with hepatitis C virus (HCV) infection and compensated cirrhosis. METHODS We did this single-arm, open-label, multicentre phase 3 study at 40 sites in Belgium, Canada, Germany, South Africa, Spain, and the USA. We enrolled patients aged 18 years or older with HCV genotype 1, 2, 4, 5, or 6 infection and compensated cirrhosis. Patients were either HCV treatment-naive or had not responded to treatment with interferon or pegylated interferon with or without ribavirin, or sofosbuvir plus ribavirin with or without pegylated interferon. Oral glecaprevir (300 mg) coformulated with pibrentasvir (120 mg) was administered once daily for 12 weeks. The primary efficacy endpoint was sustained virological response at post-treatment week 12 (HCV RNA <15 IU/mL). We assessed efficacy and safety in all patients who received at least one dose of study drug (intention-to-treat population). This study is registered with ClinicalTrials.gov, number NCT02642432. FINDINGS Between Dec 7, 2015, and May 4, 2016, we enrolled 146 patients with compensated cirrhosis, of whom 48 (33%) had genotype 1a HCV infection, 39 (27%) had genotype 1b infection, 34 (23%) had genotype 2 infection, 16 (11%) had genotype 4 infection, two (1%) had genotype 5 infection, and seven (5%) had genotype 6 infection. 12 weeks after treatment, 145 patients (99%, 95% CI 98-100) achieved sustained virological response, with one (1%) relapse at post-treatment week 8. We recorded 101 (69%) adverse events, of which 65 (64%) were mild. The most common adverse events were fatigue (n=28 [19%]) and headache (n=20 [14%]). 11 (8%) patients had serious adverse events, none of which were deemed related to study drugs. No patients had elevations in alanine aminotransferase and no patients prematurely discontinued treatment because of adverse events. INTERPRETATION Our results show that 99% of patients treated with once-daily glecaprevir plus pibrentasvir achieved a sustained virological response at 12 weeks. Furthermore, this drug regimen had a favourable safety profile in previously treated or untreated patients with chronic HCV genotype 1, 2, 4, 5, or 6 infection and compensated cirrhosis. These findings could help simplify treatment algorithms and reduce treatment burden. FUNDING AbbVie.

Glecaprevir and Pibrentasvir for 12 Weeks for HCV Genotype 1 Infection and Prior Direct‐acting Antiviral Treatment

Although direct‐acting antiviral (DAA) therapies for chronic hepatitis C virus (HCV) infection have demonstrated high rates of sustained virologic response, virologic failure may still occur, potentially leading to the emergence of viral resistance, which can decrease the effectiveness of subsequent treatment. Treatment options for patients who failed previous DAA‐containing regimens, particularly those with nonstructural protein 5A inhibitors, are limited and remain an area of unmet medical need. This phase 2, open‐label study (MAGELLAN‐1) evaluated the efficacy and safety of glecaprevir (GLE) + pibrentasvir (PIB) ± ribavirin (RBV) in HCV genotype 1–infected patients with prior virologic failure to HCV DAA‐containing therapy. A total of 50 patients without cirrhosis were randomized to three arms: 200 mg GLE + 80 mg PIB (arm A), 300 mg GLE + 120 mg PIB with 800 mg once‐daily RBV (arm B), or 300 mg GLE + 120 mg PIB without RBV (arm C). By intent‐to‐treat analysis, sustained virologic response at posttreatment week 12 was achieved in 100% (6/6, 95% confidence interval 61‐100), 95% (21/22, 95% confidence interval 78‐99), and 86% (19/22, 95% confidence interval 67‐95) of patients in arms A, B, and C, respectively. Virologic failure occurred in no patients in arm A and in 1 patient each in arms B and C (two patients were lost to follow‐up in arm C). The majority of adverse events were mild in severity; no serious adverse events related to study drug and no relevant laboratory abnormalities in alanine aminotransferase, total bilirubin, or hemoglobin were observed. Conclusion: The combination of GLE and PIB was highly efficacious and well tolerated in patients with HCV genotype 1 infection and prior failure of DAA‐containing therapy; RBV coadministration did not improve efficacy. (Hepatology 2017;66:389–397).

Glecaprevir–Pibrentasvir for 8 or 12 Weeks in HCV Genotype 1 or 3 Infection

BACKGROUND Glecaprevir and pibrentasvir are direct‐acting antiviral agents with pangenotypic activity and a high barrier to resistance. We evaluated the efficacy and safety of 8‐week and 12‐week courses of treatment with 300 mg of glecaprevir plus 120 mg of pibrentasvir in patients without cirrhosis who had hepatitis C virus (HCV) genotype 1 or 3 infection. METHODS We conducted two phase 3, randomized, open‐label, multicenter trials. Patients with genotype 1 infection were randomly assigned in a 1:1 ratio to receive once‐daily glecaprevir–pibrentasvir for either 8 or 12 weeks. Patients with genotype 3 infection were randomly assigned in a 2:1 ratio to receive 12 weeks of treatment with either glecaprevir–pibrentasvir or sofosbuvir–daclatasvir. Additional patients with genotype 3 infection were subsequently enrolled and nonrandomly assigned to receive 8 weeks of treatment with glecaprevir–pibrentasvir. The primary end point was the rate of sustained virologic response 12 weeks after the end of treatment. RESULTS In total, 1208 patients were treated. The rate of sustained virologic response at 12 weeks among genotype 1–infected patients was 99.1% (95% confidence interval [CI], 98 to 100) in the 8‐week group and 99.7% (95% CI, 99 to 100) in the 12‐week group. Genotype 3–infected patients who were treated for 12 weeks had a rate of sustained virologic response at 12 weeks of 95% (95% CI, 93 to 98; 222 of 233 patients) with glecaprevir–pibrentasvir and 97% (95% CI, 93 to 99.9; 111 of 115) with sofosbuvir–daclatasvir; 8 weeks of treatment with glecaprevir–pibrentasvir yielded a rate of 95% (95% CI, 91 to 98; 149 of 157 patients). Adverse events led to discontinuation of treatment in no more than 1% of patients in any treatment group. CONCLUSIONS Once‐daily treatment with glecaprevir–pibrentasvir for either 8 weeks or 12 weeks achieved high rates of sustained virologic response among patients with HCV genotype 1 or 3 infection who did not have cirrhosis. (Funded by AbbVie; ENDURANCE‐1 and ENDURANCE‐3 ClinicalTrials.gov numbers, NCT02604017 and NCT02640157.)

Glecaprevir/pibrentasvir for hepatitis C virus genotype 3 patients with cirrhosis and/or prior treatment experience: A partially randomized phase 3 clinical trial

This study assessed the efficacy and safety of ribavirin‐free coformulated glecaprevir/pibrentasvir (G/P) in patients with hepatitis C virus genotype 3 infection with prior treatment experience and/or compensated cirrhosis, a patient population with limited treatment options. SURVEYOR‐II, Part 3 was a partially randomized, open‐label, multicenter, phase 3 study. Treatment‐experienced (prior interferon or pegylated interferon ± ribavirin or sofosbuvir plus ribavirin ± pegylated interferon therapy) patients without cirrhosis were randomized 1:1 to receive 12 or 16 weeks of G/P (300 mg/120 mg) once daily. Treatment‐naive or treatment‐experienced patients with compensated cirrhosis were treated with G/P for 12 or 16 weeks, respectively. The primary efficacy endpoint was the percentage of patients with sustained virologic response at posttreatment week 12 (SVR12). Safety was evaluated throughout the study. There were 131 patients enrolled and treated. Among treatment‐experienced patients without cirrhosis, SVR12 was achieved by 91% (20/22; 95% confidence interval [CI], 72‐97) and 95% (21/22; 95% CI, 78‐99) of patients treated with G/P for 12 or 16 weeks, respectively. Among those with cirrhosis, SVR12 was achieved by 98% (39/40; 95% CI, 87‐99) of treatment‐naive patients treated for 12 weeks and 96% (45/47; 95% CI, 86‐99) of patients with prior treatment experience treated for 16 weeks. No adverse events led to discontinuation of study drug, and no serious adverse events were related to study drug. Conclusion: Patients with hepatitis C virus genotype 3 infection with prior treatment experience and/or compensated cirrhosis achieved high SVR12 rates following 12 or 16 weeks of treatment with G/P. The regimen was well tolerated. (Hepatology 2018;67:514‐523).

Glecaprevir/Pibrentasvir in patients with hepatitis C virus genotype 1 or 4 and past direct‐acting antiviral treatment failure

Patients with hepatitis C virus (HCV) who have virological failure (VF) after treatment containing a nonstructural protein 5A (NS5A) inhibitor have limited retreatment options. MAGELLAN‐1 Part 2 was a randomized, open‐label, phase 3 study to evaluate the efficacy and safety of ribavirin (RBV)‐free glecaprevir and pibrentasvir (G/P; 300 mg/120 mg) in patients with chronic HCV and past VF on at least one NS3/4A protease and/or NS5A inhibitor‐containing therapy. Patients with compensated liver disease, with or without cirrhosis, and HCV genotype (GT) 1, 4, 5, or 6 were randomized 1:1 to receive 12 or 16 weeks of G/P. The primary endpoint was sustained virological response (SVR) at 12 weeks posttreatment (SVR12). Among 91 patients treated, 87 had GT1 and 4 had GT4 infection. SVR12 was achieved by 89% (39 of 44) and 91% (43 of 47) of patients who received 12 and 16 weeks of G/P, respectively. Virological relapse occurred in 9% (4 of 44) of patients treated with 12 weeks of G/P; there were no relapses with 16 weeks of treatment. Past treatment history with one class of inhibitor (protease or NS5A) had no impact on SVR12, whereas past treatment with both classes of inhibitors was associated with lower SVR12 rate. The most common adverse event (AE) was headache (≥10% of patients), and there were no serious AEs assessed as related to study drugs or AEs leading to discontinuation. Conclusion: Sixteen weeks of G/P treatment achieved a high SVR12 rate in patients with HCV GT1 infection and past failure to regimens containing either NS5A inhibitors or NS3 protease inhibitors. (Hepatology 2018;67:1253‐1260)

Glecaprevir/Pibrentasvir for HCV Genotype 3 Patients with Cirrhosis and/or Prior Treatment Experience: A Partially Randomized Phase III Clinical Trial

This study assessed the efficacy and safety of ribavirin‐free coformulated glecaprevir/pibrentasvir (G/P) in patients with hepatitis C virus genotype 3 infection with prior treatment experience and/or compensated cirrhosis, a patient population with limited treatment options. SURVEYOR‐II, Part 3 was a partially randomized, open‐label, multicenter, phase 3 study. Treatment‐experienced (prior interferon or pegylated interferon ± ribavirin or sofosbuvir plus ribavirin ± pegylated interferon therapy) patients without cirrhosis were randomized 1:1 to receive 12 or 16 weeks of G/P (300 mg/120 mg) once daily. Treatment‐naive or treatment‐experienced patients with compensated cirrhosis were treated with G/P for 12 or 16 weeks, respectively. The primary efficacy endpoint was the percentage of patients with sustained virologic response at posttreatment week 12 (SVR12). Safety was evaluated throughout the study. There were 131 patients enrolled and treated. Among treatment‐experienced patients without cirrhosis, SVR12 was achieved by 91% (20/22; 95% confidence interval [CI], 72‐97) and 95% (21/22; 95% CI, 78‐99) of patients treated with G/P for 12 or 16 weeks, respectively. Among those with cirrhosis, SVR12 was achieved by 98% (39/40; 95% CI, 87‐99) of treatment‐naive patients treated for 12 weeks and 96% (45/47; 95% CI, 86‐99) of patients with prior treatment experience treated for 16 weeks. No adverse events led to discontinuation of study drug, and no serious adverse events were related to study drug. Conclusion: Patients with hepatitis C virus genotype 3 infection with prior treatment experience and/or compensated cirrhosis achieved high SVR12 rates following 12 or 16 weeks of treatment with G/P. The regimen was well tolerated. (Hepatology 2018;67:514‐523).

High Svr Rates with ABT-493 + ABT-530 Co-Administered for 8 Weeks in Non-Cirrhotic Patients with HCV Genotype 3 Infection

PS098 Partially randomised, open-label, multicentre phase 2 trial evaluating the dose combination of ABT-493 and ABT-530 identified in the dose-ranging part 1 of this study SURVEYOR-II Part 2 Study Design *RBV dosed once-daily ABT-493 300 mg ABT-530 120 mg ABT-493 300 mg ABT-530 120 mg ABT-493 300 mg ABT-530 120 mg ABT-493 300 mg ABT-530 120 mg ABT-493 300 mg ABT-530 120 mg RBV* 800 mg GT3 N=29 GT2 N=54

Pharmacokinetics, Safety, and Tolerability Following Single and Multiple Doses of Pibrentasvir in a First‐in‐Human Study

This first‐in‐human dose‐ascending study investigated pharmacokinetics, safety, and tolerability of pibrentasvir following single and multiple doses in healthy volunteers. Additionally, the effects of food and ritonavir on pibrentasvir were assessed in a crossover study design. The starting dose of pibrentasvir was selected based on the no‐observed‐adverse‐effect‐level exposure from preclinical studies. Dose escalations of subsequent cohorts were dependent on reviews of the safety, tolerability, and pharmacokinetic data from previous dose cohorts. Pibrentasvir exposures increased in a greater than dose‐proportional manner across the 1.5‐ to 120‐mg dose range and became linear across the 120‐ to 600‐mg dose range. Following multiple dosing, pibrentasvir steady state was attained by day 5 with an accumulation ratio of 25% to 35%. Pibrentasvir harmonic mean terminal half‐life ranged from 20 to 22 hours. Food had minimal effect (<14%) on pibrentasvir bioavailability, but ritonavir increased pibrentasvir peak concentration and area under the concentration‐time curve by 60% and 89%, respectively. All adverse events were assessed by the investigator as mild, and no clinically significant vital signs, electrocardiogram, or clinical laboratory values were observed. The pharmacokinetic results from this study support once‐daily dosing and administration of pibrentasvir without regard to food. A maximum tolerated dose was not attained in the single‐ and multiple‐ascending‐dose assessments for pibrentasvir.

Pharmacokinetics, Safety, and Tolerability of Glecaprevir and Pibrentasvir in Healthy White, Chinese, and Japanese Adult Subjects

Glecaprevir and pibrentasvir are direct‐acting antiviral agents being developed as combination therapy for the treatment of chronic hepatitis C virus infection. The aim of the present studies was to assess the effect of race and ethnicity (white, Han Chinese, Japanese) on the pharmacokinetics and safety of multiple oral doses of glecaprevir and pibrentasvir given alone and in combination. Two multiple‐dose, single‐center, phase 1 studies were conducted in healthy adult male and female subjects (n = 170) of respective Asian and white race/ethnicity. Glecaprevir (100, 200, 300, or 700 mg once daily) and pibrentasvir (80, 120, or 160 mg once daily) were administered alone for 7 days followed by the combination of both direct‐acting antiviral agents for another 7 days. Intensive blood sampling was performed, and pharmacokinetic parameters were estimated by noncompartmental analyses. ANOVA was employed to evaluate for differences of steady‐state glecaprevir and pibrentasvir exposures between Asian (Japanese or Han Chinese) and white subjects. Glecaprevir and pibrentasvir exposures in Han Chinese and Japanese were similar to those in whites across dose levels. The nonlinear dose‐exposure relationships for glecaprevir and pibrentasvir were similar across Japanese, Han Chinese, and white subjects, and the safety profiles of the agents were comparable across these groups. The results of these studies demonstrate that race/ethnicity has no clinically meaningful impact on direct‐acting antiviral agent exposures, safety, or tolerability of the glecaprevir and pibrentasvir combination. This is supported in part by the large global registration program of the pangenotypic, coformulated fixed‐dose glecaprevir/pibrentasvir regimen and allows for inclusion of diverse ethnic populations.

Efficacy and Pharmacokinetics of Glecaprevir and Pibrentasvir With Concurrent Use of Acid-Reducing Agents in Patients With Chronic HCV Infection

Background & Aims Proton pump inhibitors (PPIs) are commonly prescribed to treat acid‐related disorders. Some direct‐acting antiviral regimens for chronic hepatitis C virus (HCV) infection have reduced efficacy in patients taking concomitant acid‐reducing agents, including PPIs, due to interactions between drugs. We analyzed data from 9 multicenter, phase 2 and 3 trials to determine the efficacy and pharmacokinetics of an HCV therapeutic regimen comprising glecaprevir and pibrentasvir (glecaprevir/pibrentasvir) in patients taking concomitant acid‐reducing agents. Methods We analyzed data from 2369 patients infected with HCV genotypes 1–6 and compensated liver disease treated with an all‐oral regimen of glecaprevir/pibrentasvir for 8–16 weeks. We compared efficacy and pharmacokinetics among patients receiving at least 1 dose of an acid‐reducing agent (a PPI, an H2 blocker, or antacid). High‐dose PPI was defined as daily dose greater than 20 mg omeprazole dose equivalent. The objectives were to evaluate rate of sustained virologic response 12 weeks post‐treatment (SVR12) and to assess steady‐state glecaprevir and pibrentasvir exposures in patients on acid‐reducing agents. Results Of the 401 patients (17%) who reported use of acid‐reducing agents, 263 took PPIs (11%; 109 patients took a high‐dose PPI and 154 patients took a low‐dose PPI). Rates of SVR12 were 97.0% among patients who used acid‐reducing agents and 97.5% among those not using acid‐reducing agents (P = .6). An SVR12 was achieved in 96.3% taking a high‐dose PPI and 97.4% taking a low‐dose PPI, with no virologic failures in those receiving a high‐dose PPI (P = .7). Glecaprevir, but not pibrentasvir, bioavailability was affected; its exposure decreased by 41% in patients taking a high‐dose PPI. Conclusions In an analysis of data from 9 clinical trials, we observed a high rate of SVR12 (approximately 97%) among patients treated with glecaprevir/pibrentasvir for HCV infection—even among patients taking concomitant ARA or high‐dose PPI. This was despite decreased glecaprevir exposures in patients when on high‐dose PPIs. ClinicalTrials.gov numbers, NCT02243280 (SURVEYOR‐I), NCT02243293 (SURVEYOR‐II), NCT02604017 (ENDURANCE‐1), NCT02640482 (ENDURANCE‐2), NCT02640157 (ENDURANCE‐3), NCT02636595 (ENDURANCE‐4), NCT02642432 (EXPEDITION‐1), NCT02651194 (EXPEDITION‐4), NCT02446717 (MAGELLAN‐I).