Long-Term Follow-Up of Children Treated With Peginterferon and Ribavirin for Hepatitis C Virus Infection.

OBJECTIVES: The aim of the study was to describe the 5-year follow-up of children who received peginterferon and ribavirin in a global, open-label study. METHODS: A 5-year follow-up study of 107 children and adolescents ages 3 to 17 years with chronic hepatitis C virus infection who received peginterferon and ribavirin for 24 or 48 weeks. No drugs were administered during follow-up. RESULTS: Ninety-four patients were enrolled in the long-term follow-up portion of the study; the median duration of follow-up was 287 weeks (range, 73-339). Of 63 patients with sustained virologic response who were enrolled, 54 completed 5 years of follow-up; none had relapse in the 5-year follow-up period. Significant decreases in height z scores were observed during treatment. The effect of treatment on height z score was larger in patients treated for 48 weeks compared with those treated for 24 weeks (mean change from baseline to the end of treatment was -0.13 [P < 0.001] and -0.44 [P < 0.001] in the 24- and 48-week treatment groups, respectively). Among patients treated for 24 weeks, full recovery of height z scores to baseline was observed by 1 year of follow-up, whereas only partial recovery was observed during 5 years of follow-up in patients treated for 48 weeks (mean change from baseline to the final follow-up visit was -0.16 (P = NS) and -0.32 (P < 0.05) in the 24- and 48-week treatment groups, respectively). Similar patterns were observed for weight and body mass index z scores. CONCLUSIONS: Impairment of growth should be considered when assessing the risk-benefit profile of peginterferon/ribavirin therapy in children with hepatitis C virus infection. In deciding to treat children with chronic hepatitis C virus, considerations should include both deferring treatment in patients during optimal growth periods, and the possibility that interferon-free regimens may be available to children in the next 5 to 10 years.

Staging chronic hepatitis C in seven categories using fibrosis biomarker (FibroTest™) and transient elastography (FibroScan®).

BACKGROUND & AIMS: FibroTest™ (FT) and Transient Elastography (TE) have been validated as non-invasive markers of METAVIR fibrosis stages from F0 to F4 using biopsy, and as prognostic markers of liver related mortality in patients with chronic hepatitis C. The aim was to extend the validation of FT and TE as markers of critical steps defined by occurrence of cirrhosis without complications (F4.1), esophageal varices (F4.2), and severe complications (F4.3): primary liver cancer, variceal bleeding, or decompensation (ascites, encephalopathy, or jaundice). METHODS: The updated individual data of 3927 patients (1046 cirrhotics) without complications at baseline were pooled from three prospective cohorts called "EPIC", "Paris", and "Bordeaux" cohorts. RESULTS: At 5 years, among 501 patients without varices at baseline (F4.1) varices occurred in 19 patients [F4.2 incidence of 4.0% (95% CI 2.2-5.8)]. The predictive performance (AUROC) of FT was 0.77 (0.66-0.84; p<0.001). At 10 years severe complications occurred in 203 patients, [F4.3 incidence of 13.4% (9.6-17.1)], including primary liver cancer in 84 patients [6.4% (3.5-9.3)]. FT was predictive (Cox adjusted on treatment) of severe complications [AUROC 0.79 (76-82); p<0.0001], including primary liver cancer [AUROC 0.84 (80-87); p<0.0001]. Similarly TE was predictive of severe complications [AUROC 0.77 (72-81); p<0.0001], including primary liver cancer [AUROC 0.86 (81-90); p<0.0001]. CONCLUSIONS: FibroTest™ and TE increase were associated with the occurrence of all severe complications including hepatocellular carcinoma, hepatic insufficiency, and variceal bleeding. FibroTest™ increase was also associated with the occurrence of esophageal varices.

Overall safety profile of boceprevir plus peginterferon alfa-2b and ribavirin in patients with chronic hepatitis C genotype 1: a combined analysis of 3 phase 2/3 clinical trials.

BACKGROUND & AIMS: Triple therapy with peginterferon/ribavirin (PR) plus an NS3 protease inhibitor has emerged as the standard-of-care for patients with chronic hepatitis C genotype-1. We provide a detailed safety analysis comparing PR to boceprevir plus PR (BOC/PR) across three phase 2/3 studies. METHODS: SPRINT-1 was an open-label phase 2 study in 595 treatment-naive patients. In the two phase 3 studies, 1500 patients (1097 treatment-naive, SPRINT-2; 403 treatment-failure, RESPOND-2) were randomized to receive PR alone, or one of two regimens where BOC was added to PR after a 4-wk PR lead-in. In this analysis, the respective BOC/PR and PR arms were combined for all three trials. The benefit of shortened duration of treatment using response-guided therapy (RGT) was also explored in the SPRINT-2 trial. RESULTS: Only two adverse events, anaemia and dysgeusia, occurred 20% more often with the BOC-containing regimens compared with PR. Nausea, diarrhoea and neutropenia were the only other common events with an incidence of at least 5% greater when BOC was added to the PR backbone. The proportions of patients reporting serious adverse events (AE), life-threatening AEs, and study drug discontinuation because of an AE were similar in the PR and BOC/PR arms. In treatment-naive patients, RGT generally did not result in a lower frequency of common AEs; however, RGT led to decreased exposure to all 3 study drugs and to a decrease in the mean duration of several clinically relevant AEs such as anaemia, neutropenia, fatigue and depression, as well as earlier normalization of haemoglobin and neutrophil counts. CONCLUSIONS: The safety profile of BOC combination therapy largely reflects the known profile of peginterferon and ribavirin, with incremental haematolgical effects and dysgeusia. Shorter treatment duration with RGT significantly reduced the duration of AEs.

Boceprevir plus peginterferon α-2b/ribavirin in chronic hepatitis C genotype 1: impact of baseline viral load on sustained virologic response.

BACKGROUND: Baseline viral load is a predictor of treatment outcome in patients with hepatitis C virus (HCV) infection receiving peginterferon and ribavirin. The impact of baseline viral load on sustained virologic response (SVR) after boceprevir-based therapy is unknown. METHODS: This retrospective analysis included patients with chronic HCV genotype 1 infection who were previously untreated or were previous treatment failures. Virologic response was assessed according to baseline viral load (≤1 million IU/mL, >1 to ≤5 million IU/mL, >5 to ≤10 million IU/mL, and >10 million IU/mL). RESULTS: SVR was higher in patients receiving boceprevir plus peginterferon and ribavirin than in those receiving peginterferon and ribavirin alone, regardless of baseline viral load. Patients with a baseline viral load ≤1 million IU/mL had the highest SVR (boceprevir plus peginterferon and ribavirin, 78% to 83%; peginterferon and ribavirin, 33% to 63%). Among patients with baseline viral load >1 million IU/mL, SVR rates were 57% to 68% in patients receiving boceprevir plus peginterferon and ribavirin, and 11% to 41% in patients receiving peginterferon and ribavirin. Relapse was higher in patients receiving peginterferon and ribavirin (previously untreated, 12% to 40%; previous treatment failures, 17% to 67%) than in those receiving boceprevir plus peginterferon and ribavirin (previously untreated, 3% to 12%; previous treatment failure, 9% to 16%), irrespective of baseline viral load. CONCLUSIONS: The efficacy of boceprevir plus peginterferon and ribavirin was unaffected by baseline viral loads >1 million IU/mL, whereas viral burden >1 million IU/mL was associated with lower SVR with peginterferon and ribavirin. Relapse rates were lower with boceprevir plus peginterferon and ribavirin than with peginterferon and ribavirin, and were unaffected by baseline viral load.

Predictors of consent to pharmacogenomics testing in the IDEAL study.

INTRODUCTION: Pharmacogenomic testing is important in developing individualized therapeutic approaches. In the phase 3 IDEAL (Individualized Dosing to Assess Optimal Pegylated Interferon Therapy) clinical trial, a subset of patients receiving peginterferon and ribavirin for treatment of chronic hepatitis C agreed to provide blood samples for genetic testing. Genome-wide association studies subsequently identified associations between IL28B polymorphism and sustained virologic response, and ITPA polymorphism and ribavirin-associated anemia. OBJECTIVE: To characterize the groups of patients who accepted or declined pharmacogenomic testing in the IDEAL study. METHODS: Clinical and demographic factors and treatment outcomes were compared at all sites that had approved pharmacogenomic testing. Differences between patients who consented to and declined pharmacogenomic testing were analyzed using Student's t-test and χ²-test. RESULTS: In total, 109 of 118 sites participated in the pharmacogenomic substudy, and 1674 of 2949 (57%) patients enrolled at these sites consented to pharmacogenomic testing. More patients treated in academic medical centers than in community centers (60 vs. 52%, P<0.001) provided consent. More men than women (58 vs. 54%, P=0.04) consented to pharmacogenomic testing. There was no significant difference in pharmacogenomic participation between patients from different racial groups, including whites and African Americans (58 vs. 54%, P=0.07). Treatment outcomes were also similar according to pharmacogenomic participation. CONCLUSION: In the IDEAL study, patient consent to pharmacogenomic testing did not introduce selection bias. Treatment at an academic center and male sex were associated with higher rates of pharmacogenomic testing consent. Efficacy and safety outcomes were similar in patients who accepted and declined pharmacogenomic testing.

Effects of ribavirin dose reduction vs erythropoietin for boceprevir-related anemia in patients with chronic hepatitis C virus genotype 1 infection--a randomized trial.

BACKGROUND & AIMS: Treatment of hepatitis C virus (HCV) infection with boceprevir, peginterferon, and ribavirin can lead to anemia, which has been managed by reducing ribavirin dose and/or erythropoietin therapy. We assessed the effects of these anemia management strategies on rates of sustained virologic response (SVR) and safety. METHODS: Patients (n = 687) received 4 weeks of peginterferon and ribavirin followed by 24 or 44 weeks of boceprevir (800 mg, 3 times each day) plus peginterferon and ribavirin. Patients who became anemic (levels of hemoglobin approximately ≤10 g/dL) during the study treatment period (n = 500) were assigned to groups that were managed by ribavirin dosage reduction (n = 249) or erythropoietin therapy (n = 251). RESULTS: Rates of SVR were comparable between patients whose anemia was managed by ribavirin dosage reduction (71.5%) vs erythropoietin therapy (70.9%), regardless of the timing of the first intervention to manage anemia or the magnitude of ribavirin dosage reduction. There was a threshold for the effect on rate of SVR: patients who received <50% of the total milligrams of ribavirin assigned by the protocol had a significantly lower rate of SVR (P < .0001) than those who received ≥50%. Among patients who did not develop anemia, the rate of SVR was 40.1%. Eleven thromboembolic adverse events were reported in 9 of 295 patients who received erythropoietin, compared with 1 of 392 patients who did not receive erythropoietin. CONCLUSIONS: Reduction of ribavirin dosage can be the primary approach for management of anemia in patients receiving peginterferon, ribavirin, and boceprevir for HCV infection. Reduction in ribavirin dosage throughout the course of triple therapy does not affect rates of SVR. However, it is important that the patient receives at least 50% of the total amount (milligrams) of ribavirin assigned by response-guided therapy. ClinicalTrials.gov number, NCT01023035.

Resistance-associated amino acid variants associated with boceprevir plus pegylated interferon-α2b and ribavirin in patients with chronic hepatitis C in the SPRINT-1 trial.

BACKGROUND: Resistance to direct-acting antivirals represents a new challenge in the treatment of chronic hepatitis C. METHODS: SPRINT-1 was a randomized study of treatment-naive patients with genotype (G) 1 hepatitis C infection (n=595) that evaluated the safety and efficacy of boceprevir (BOC) when added to pegylated interferon-α2b plus ribavirin (PR). Plasma samples collected at protocol-specified visits were analysed by population sequencing for detection of BOC-associated resistance-associated variants (RAVs). RESULTS: A total of 17/24 (71%) patients randomized to BOC with baseline RAVs achieved sustained virological response (SVR). V55A/I (n=14), Q41H (n=11) and T54S (n=9) were the most frequently detected polymorphisms at baseline. Seven non-SVR patients with baseline RAVs had V55A (relapse, n=3; breakthrough, n=1; and non-response, n=1) and/or R155K (non-response, n=2). In total, 63/144 (44%) patients with sequenced post-baseline samples (2 SVR, 61 non-SVR) had detectable RAVs after BOC treatment (G1a: R155K [39/49; 80%], V36M [37/49; 76%] and T54S [24/49; 49%]; G1b: T54S [3/11; 27%], T54A [4/11; 35%], A156S [2/11; 18%] and V170A [2/11; 18%]). RAV frequency varied according to the virological response: 90%, 67%, 27% and 37% of breakthrough, incomplete virological response, relapse and non-responder patients, respectively, had post-baseline RAVs present. Similar RAVs were identified in both the PR lead-in and no-lead-in arms and the frequency of post-baseline RAVs was highest in the low-dose ribavirin arm. CONCLUSIONS: SVR rates were not compromised among patients with RAVs at baseline; however, a lower starting mg/kg dose of ribavirin was associated with a higher frequency of post-baseline RAVs.

Boceprevir with peginterferon alfa-2a-ribavirin is effective for previously treated chronic hepatitis C genotype 1 infection.

BACKGROUND & AIMS: The addition of boceprevir to therapy with peginterferon alfa-2b and ribavirin results in significantly higher rates of sustained virologic response (SVR) in previously treated patients with chronic hepatitis C virus (HCV) genotype-1 infection, compared with peginterferon alfa-2b and ribavirin alone. We assessed SVR with boceprevir plus peginterferon alfa-2a-ribavirin (PEG2a/R) in patients with identical study entry criteria. METHODS: In a double-blind, placebo-controlled trial, 201 patients with HCV genotype-1 who had relapsed or not responded to previous therapy were assigned to groups (1:2) and given a 4-week lead-in phase of PEG2a/R, followed by placebo plus PEG2a/R for 44 weeks (PEG2a/R) or boceprevir plus PEG2a/R for 44 weeks (BOC/PEG2a/R). The primary end point was SVR 24 weeks after therapy ended. RESULTS: The addition of boceprevir after 4 weeks of lead-in therapy with PEG2a/R significantly increased the rate of SVR from 21% in the PEG2a/R group to 64% in the BOC/PEG2a/R group (P < .0001). Among patients with poor response to interferon therapy (<1-log(10) decline in HCV RNA at week 4), 39% in the BOC/PEG2a/R group had SVRs, compared with none of the patients in the PEG2a/R group. Among patients with good response to interferon (≥1-log(10) decline), 71% in the BOC/PEG2a/R group had SVRs, compared with 25% in the PEG2a/R group. A ≥1-log(10) decline in HCV RNA at treatment week 4 was the strongest independent predictor of SVR, exceeding that of IL-28B genotype. Among 8 patients who began the study with HCV amino acid variants associated with boceprevir resistance, 3 (38%) achieved SVRs. Fifty percent of patients in the BOC/PEG2a/R group developed anemia (hemoglobin <10.0 g/dL), compared with 27% in the PEG2a/R group; 43% vs 21%, respectively, developed neutropenia (neutrophil count <750/mm(3)). CONCLUSIONS: The addition of boceprevir after 4 weeks of lead-in therapy with PEG2a/R caused significantly higher rates of SVR in previously treated patients with chronic HCV genotype-1 infection, compared with patients given only PEG2a/R. ClinicalTrials.gov Identifier: NCT00845065.

Anemia during treatment with peginterferon Alfa-2b/ribavirin and boceprevir: Analysis from the serine protease inhibitor therapy 2 (SPRINT-2) trial.

UNLABELLED: Boceprevir (BOC) added to peginterferon alfa-2b (PegIFN) and ribavirin (RBV) significantly increases sustained virologic response (SVR) rates over PegIFN/RBV alone in previously untreated adults with chronic hepatitis C genotype 1. We evaluate the relationship of incident anemia with triple therapy. A total of 1,097 patients received a 4-week lead-in of PegIFN/RBV followed by: (1) placebo plus PegIFN/RBV for 44 weeks (PR48); (2) BOC plus PegIFN/RBV using response-guided therapy (BOC/RGT); and (3) BOC plus PegIFN/RBV for 44 weeks (BOC/PR48). The management of anemia (hemoglobin [Hb]<10 g/dL) included RBV dose reduction and/or erythropoietin (EPO) use. A total of 1,080 patients had ≥1 Hb measurement during treatment. The incidence of anemia was 50% in the BOC arms combined (363/726) and 31% in the PR48 arm (108/354, P<0.001). Among BOC recipients, lower baseline Hb and creatinine clearance were associated with incident anemia. In the BOC-containing arms, anemia was managed by the site investigators as follows: EPO without RBV dose reduction, 38%; RBV dose reduction without EPO, 8%; EPO with RBV dose reduction, 40%; and neither RBV dose reduction nor EPO, 14%. SVR rates were not significantly affected by management strategy (70%-74%), and overall patients with anemia had higher rates of SVR than those who did not develop anemia (58%). Serious and life-threatening adverse events (AEs) and discontinuations due to AEs among BOC-treated patients did not differ by EPO use. CONCLUSION: With BOC/PR therapy, SVR rates in patients with incident anemia were higher than nonanemic patients and did not vary significantly according to the investigator-selected approach for anemia management. Prospective studies are needed to confirm this observation.

Improved inflammatory activity with peginterferon alfa-2b maintenance therapy in non-cirrhotic prior non-responders: a randomized study.

BACKGROUND & AIMS: Therapeutic options for patients failing hepatitis C retreatment are limited. EPIC(3) included a prospective trial assessing long-term peginterferon alfa-2b (PegIFNα-2b) maintenance therapy in patients with METAVIR fibrosis scores (MFS) of F2 or F3 who previously failed hepatitis C retreatment. METHODS: Patients with F2/F3 MFS who failed retreatment were randomized to PegIFNα-2b (0.5 µg/kg/week, n=270) or observation (n=270) for 36 months. Blinded liver biopsies obtained before retreatment and after maintenance therapy were evaluated using MFS and activity scores, and confirmatory testing was performed using FibroTest and ActiTest. RESULTS: In total, 348 patients had paired biopsies: 192 patients had missing post-treatment biopsies and were considered as having no change in fibrosis/activity scores. In total, 16% of patients receiving PegIFNα-2b and 11% of observation patients had improvement in MFS (p=0.32). More PegIFNα-2b than observation patients had improvement in activity score (20% vs. 9%; p <0.001). Among patients treated for >2.5 years, improvement in MFS or activity score was more common with PegIFNα-2b than observation (21% vs. 14%, p=0.08 and 26% vs. 10%, p <0.001). FibroTest and ActiTest evaluations indicated significant benefit associated with PegIFNα-2b in terms of reduced fibrosis progression and improved activity score. The safety profile of PegIFNα-2b was similar to previous studies. CONCLUSIONS: PegIFNα-2b did not significantly improve MFS estimated by biopsy compared with observation; however, activity scores were significantly improved and MFS trended toward increased improvement with treatment durations >2.5 years. Both FibroTest and ActiTest were significantly improved during maintenance therapy.

Efficacy and safety of boceprevir plus peginterferon-ribavirin in patients with HCV G1 infection and advanced fibrosis/cirrhosis.

BACKGROUND & AIMS: We assessed the safety and efficacy of boceprevir (BOC) plus peginterferon-ribavirin (PR) in patients with HCV-G1 infection and advanced fibrosis/cirrhosis (Metavir F3/F4). METHODS: In two randomized controlled studies of previously untreated and previous treatment failures, patients received a 4-week lead-in of PR followed by PR plus placebo for 44 weeks (PR48); PR plus BOC using response guided therapy (BOC/RGT); or PR plus BOC for 44 weeks (BOC/PR48). RESULTS: The trials enrolled 178 patients with F3/4. HCV RNA levels at week 4 and 8 were highly predictive of response. No patient with F3/4 in the PR48 arm with a <1 log(10) decline in HCV RNA at week 4 achieved SVR, whereas those randomized to BOC/RGT or BOC/PR48 had SVR rates of 11-33% (F3) and 10-14% (F4). In these latter groups, patients with high baseline viral load (>2 × 10(6)IU/ml) had an overall SVR rate of 6% (2/33). For patients with a ≥1 log(10) decline at week 4, SVR rates in the BOC/PR48 arm of SPRINT-2 and RESPOND-2, respectively, were 77% and 87% vs. 18% and 50% for PR48; SVR rates in early responders (undetectable HCV RNA at week 8) were 90-93% in the BOC/PR48 arm. Neutropenia and thrombocytopenia were more common in cirrhotics than non-cirrhotics. CONCLUSIONS: BOC improves SVR rates in patients with F3/4, and longer treatment duration provides the most benefit. With triple therapy, SVR rates are modest in F4 patients with a <1 log(10) decline at week 4, thus the 4-week PR lead-in aids in the assessment of early futility.

Factors that predict response of patients with hepatitis C virus infection to boceprevir.

BACKGROUND & AIMS: Little is known about factors associated with a sustained virologic response (SVR) among patients with hepatitis C virus (HCV) infection to treatment with protease inhibitors. METHODS: Previously untreated patients (from the Serine Protease Inhibitor Therapy 2 [SPRINT-2] trial) and those who did not respond to prior therapy (from the Retreatment with HCV Serine Protease Inhibitor Boceprevir and PegIntron/Rebetol 2 [RESPOND-2] trial) received either a combination of peginterferon and ribavirin for 48 weeks or boceprevir, peginterferon, and ribavirin (triple therapy) after 4 weeks of peginterferon and ribavirin (total treatment duration, 28-48 wk). A good response to interferon was defined as a ≥ 1 log(10) decrease in HCV RNA at week 4; a poor response was defined as a <1 log(10) decrease. We used multivariate regression analyses to identify baseline factors of the host (including the polymorphism interleukin [IL]-28B rs12979860) associated with response. The polymorphism IL-28B rs8099917 also was assessed. RESULTS: In the SPRINT-2 trial, factors that predicted a SVR to triple therapy included low viral load (odds ratio [OR], 11.6), IL-28B genotype (rs 12979860 CC vs TT and CT; ORs, 2.6 and 2.1, respectively), absence of cirrhosis (OR, 4.3), HCV subtype 1b (OR, 2.0), and non-black race (OR, 2.0). In the RESPOND-2 trial, the only factor significantly associated with a SVR was previous relapse, compared with previous nonresponse (OR, 2.6). Most patients with rs12979860 CC who received triple therapy had undetectable levels of HCV RNA by week 8 (76%-89%), and were eligible for shortened therapy. In both studies, IL-28B rs12979860 CC was associated more strongly with a good response to interferon than other baseline factors; however, a ≥ 1 log(10) decrease in HCV-RNA level at week 4 was associated more strongly with SVR than IL-28B rs12979860. Combining the rs8099917 and rs12979860 genotypes does not increase the association with SVR. CONCLUSIONS: The CC polymorphism at IL-28B rs12979860 is associated with response to triple therapy and can identify candidates for shorter treatment durations. A ≥ 1 log(10) decrease in HCV RNA at week 4 of therapy is the strongest predictor of a SVR, regardless of polymorphisms in IL-28B.

The association of genetic variants with hepatic steatosis in patients with genotype 1 chronic hepatitis C infection.

BACKGROUND: Single-nucleotide polymorphisms (SNPs) in the IL28B and PNPLA3 gene regions have been associated with hepatic steatosis in genotype 1 (G1) chronic HCV infection but their clinical impacts remain to be determined. AIM: We sought to validate these associations and to explore their impact on treatment response to peginterferon and ribavirin therapy. METHODS: A total of 972 G1 HCV-infected Caucasian patients were genotyped for the SNPs rs12979860 (IL28B) and rs2896019 (PNPLA3). Multivariable analysis tested IL28B and PNPLA3 for association with the presence of any steatosis (>0 %); clinically significant steatosis (>5 %); steatosis severity (grade 0-3/4); and the interacting associations of the SNPs and hepatic steatosis to sustained viral response (SVR). RESULTS: IL28B and PNPLA3 polymorphisms were associated with the presence of any steatosis (rs12979860, p = 1.87 × 10(-7); rs2896019, p = 7.56 × 10(-4)); clinically significant steatosis (rs12979860, p = 1.82 × 10(-3); rs2896019, p = 1.27 × 10(-4)); and steatosis severity (rs12979860, p = 2.05 × 10(-8); rs2896019, p = 2.62 × 10(-6)). Obesity, hypertriglyceridemia, hyperglycemia, liver fibrosis, and liver inflammation were all independently associated with worse steatosis. Hepatic steatosis was associated with lower SVR, and this effect was attenuated by IL28B. PNPLA3 had no independent association with SVR. CONCLUSIONS: IL28B and PNPLA3 are associated with hepatic steatosis prevalence and severity in Caucasians with G1 HCV, suggesting differing potential genetic risk pathways to steatosis. IL28B attenuates the association between steatosis and SVR. Remediable metabolic risk factors remain important, independently of these polymorphisms, and remain key therapeutic goals to achieve better outcomes for patients with HCV-associated hepatic steatosis.

Refinement of stopping rules during treatment of hepatitis C genotype 1 infection with boceprevir and peginterferon/ribavirin.

UNLABELLED: In comparison with peginterferon/ribavirin alone, boceprevir with peginterferon/ribavirin significantly improves sustained virological response (SVR) rates in patients with chronic hepatitis C virus (HCV) genotype 1 infections, but treatment failure remains a significant problem. Using phase 3 trial databases, we sought to develop stopping rules for patients destined to fail boceprevir-based combination therapy in order to minimize drug toxicity, resistance, and costs in the face of ultimate futility. Exploratory post hoc analyses using data from the Serine Protease Inhibitor Therapy 2 (SPRINT-2) study (treatment-naive patients) and the Retreatment With HCV Serine Protease Inhibitor Boceprevir and Pegintron/Rebetol 2 (RESPOND-2) study (treatment-experienced patients) were undertaken to determine whether protocol-specified stopping rules (detectable HCV RNA at week 24 for SPRINT-2 and at week 12 for RESPOND-2) could be refined and harmonized. In SPRINT-2, a week 12 rule with an HCV RNA cutoff of ≥ 100 IU/mL would have discontinued therapy in 65 of 195 failures (sensitivity = 33%) without sacrificing a single SVR among 475 successes (specificity = 100%). Viral variants emerged after week 12 in 36 of the 49 evaluable patients (73%) who would have discontinued at week 12 using a ≥ 100 IU/mL stopping rule. In RESPOND-2, five of six patients with week 12 HCV RNA levels between the lower limit of detection (9.3 IU/mL) and the lower limit of quantification (25 IU/mL) who continued therapy despite the protocol-stipulated futility rule achieved SVR; one additional patient with a week 12 HCV RNA level of 148 IU/mL also continued therapy, had undetectable HCV RNA at week 16, and attained SVR. CONCLUSION: Although a stopping rule of detectable HCV RNA at week 12 would have forfeited some SVR cases, week 12 HCV RNA levels ≥ 100 IU/mL almost universally predicted a failure to achieve SVR in both treatment-naive and treatment-experienced patients. In boceprevir recipients, the combination of 2 stopping rules-an HCV RNA level ≥ 100 IU/mL at week 12 and detectable HCV RNA at week 24--maximized the early discontinuation of futile therapy and minimized premature treatment discontinuation.

Genome-wide association study of interferon-related cytopenia in chronic hepatitis C patients.

BACKGROUND & AIMS: Interferon-alfa (IFN)-related cytopenias are common and may be dose-limiting. We performed a genome wide association study on a well-characterized genotype 1 HCV cohort to identify genetic determinants of peginterferon-α (pegIFN)-related thrombocytopenia, neutropenia, and leukopenia. METHODS: 1604/3070 patients in the IDEAL study consented to genetic testing. Trial inclusion criteria included a platelet (Pl) count ≥80×10(9)/L and an absolute neutrophil count (ANC) ≥1500/mm(3). Samples were genotyped using the Illumina Human610-quad BeadChip. The primary analyses focused on the genetic determinants of quantitative change in cell counts (Pl, ANC, lymphocytes, monocytes, eosinophils, and basophils) at week 4 in patients >80% adherent to therapy (n=1294). RESULTS: 6 SNPs on chromosome 20 were positively associated with Pl reduction (top SNP rs965469, p=10(-10)). These tag SNPs are in high linkage disequilibrium with 2 functional variants in the ITPA gene, rs1127354 and rs7270101, that cause ITPase deficiency and protect against ribavirin (RBV)-induced hemolytic anemia (HA). rs1127354 and rs7270101 showed strong independent associations with Pl reduction (p=10(-12), p=10(-7)) and entirely explained the genome-wide significant associations. We believe this is an example of an indirect genetic association due to a reactive thrombocytosis to RBV-induced anemia: Hb decline was inversely correlated with Pl reduction (r=-0.28, p=10(-17)) and Hb change largely attenuated the association between the ITPA variants and Pl reduction in regression models. No common genetic variants were associated with pegIFN-induced neutropenia or leucopenia. CONCLUSIONS: Two ITPA variants were associated with thrombocytopenia; this was largely explained by a thrombocytotic response to RBV-induced HA attenuating IFN-related thrombocytopenia. No genetic determinants of pegIFN-induced neutropenia were identified.

Boceprevir for untreated chronic HCV genotype 1 infection.

BACKGROUND: Peginterferon-ribavirin therapy is the current standard of care for chronic infection with hepatitis C virus (HCV). The rate of sustained virologic response has been below 50% in cases of HCV genotype 1 infection. Boceprevir, a potent oral HCV-protease inhibitor, has been evaluated as an additional treatment in phase 1 and phase 2 studies. METHODS: We conducted a double-blind study in which previously untreated adults with HCV genotype 1 infection were randomly assigned to one of three groups. In all three groups, peginterferon alfa-2b and ribavirin were administered for 4 weeks (the lead-in period). Subsequently, group 1 (the control group) received placebo plus peginterferon-ribavirin for 44 weeks; group 2 received boceprevir plus peginterferon-ribavirin for 24 weeks, and those with a detectable HCV RNA level between weeks 8 and 24 received placebo plus peginterferon-ribavirin for an additional 20 weeks; and group 3 received boceprevir plus peginterferon-ribavirin for 44 weeks. Nonblack patients and black patients were enrolled and analyzed separately. RESULTS: A total of 938 nonblack and 159 black patients were treated. In the nonblack cohort, a sustained virologic response was achieved in 125 of the 311 patients (40%) in group 1, in 211 of the 316 patients (67%) in group 2 (P<0.001), and in 213 of the 311 patients (68%) in group 3 (P<0.001). In the black cohort, a sustained virologic response was achieved in 12 of the 52 patients (23%) in group 1, in 22 of the 52 patients (42%) in group 2 (P=0.04), and in 29 of the 55 patients (53%) in group 3 (P=0.004). In group 2, a total of 44% of patients received peginterferon-ribavirin for 28 weeks. Anemia led to dose reductions in 13% of controls and 21% of boceprevir recipients, with discontinuations in 1% and 2%, respectively. CONCLUSIONS: The addition of boceprevir to standard therapy with peginterferon-ribavirin, as compared with standard therapy alone, significantly increased the rates of sustained virologic response in previously untreated adults with chronic HCV genotype 1 infection. The rates were similar with 24 weeks and 44 weeks of boceprevir. (Funded by Schering-Plough [now Merck]; SPRINT-2 ClinicalTrials.gov number, NCT00705432.).

Boceprevir for previously treated chronic HCV genotype 1 infection.

BACKGROUND: In patients with chronic infection with hepatitis C virus (HCV) genotype 1 who do not have a sustained response to therapy with peginterferon-ribavirin, outcomes after retreatment are suboptimal. Boceprevir, a protease inhibitor that binds to the HCV nonstructural 3 (NS3) active site, has been suggested as an additional treatment. METHODS: To assess the effect of the combination of boceprevir and peginterferon-ribavirin for retreatment of patients with chronic HCV genotype 1 infection, we randomly assigned patients (in a 1:2:2 ratio) to one of three groups. In all three groups, peginterferon alfa-2b and ribavirin were administered for 4 weeks (the lead-in period). Subsequently, group 1 (control group) received placebo plus peginterferon-ribavirin for 44 weeks; group 2 received boceprevir plus peginterferon-ribavirin for 32 weeks, and patients with a detectable HCV RNA level at week 8 received placebo plus peginterferon-ribavirin for an additional 12 weeks; and group 3 received boceprevir plus peginterferon-ribavirin for 44 weeks. RESULTS: A total of 403 patients were treated. The rate of sustained virologic response was significantly higher in the two boceprevir groups (group 2, 59%; group 3, 66%) than in the control group (21%, P<0.001). Among patients with an undetectable HCV RNA level at week 8, the rate of sustained virologic response was 86% after 32 weeks of triple therapy and 88% after 44 weeks of triple therapy. Among the 102 patients with a decrease in the HCV RNA level of less than 1 log(10) IU per milliliter at treatment week 4, the rates of sustained virologic response were 0%, 33%, and 34% in groups 1, 2, and 3, respectively. Anemia was significantly more common in the boceprevir groups than in the control group, and erythropoietin was administered in 41 to 46% of boceprevir-treated patients and 21% of controls. CONCLUSIONS: The addition of boceprevir to peginterferon-ribavirin resulted in significantly higher rates of sustained virologic response in previously treated patients with chronic HCV genotype 1 infection, as compared with peginterferon-ribavirin alone. (Funded by Schering-Plough [now Merck]; HCV RESPOND-2 ClinicalTrials.gov number, NCT00708500.).

Racial differences in hepatitis C treatment eligibility.

UNLABELLED: Black Americans are disproportionally infected with hepatitis C virus (HCV) and are less likely than whites to respond to treatment with peginterferon (PEG-IFN) plus ribavirin (RBV). The impact of race on HCV treatment eligibility is unknown. We therefore performed a retrospective analysis of a phase 3B multicenter clinical trial conducted at 118 United States community and academic medical centers to evaluate the rates of and reasons for HCV treatment ineligibility according to self-reported race. In all, 4,469 patients were screened, of whom 1,038 (23.2%) were treatment ineligible. Although blacks represented 19% of treated patients, they were more likely not to be treated due to ineligibility and/or failure to complete required evaluations (40.2%) than were nonblack patients (28.5%; P < 0.001). After the exclusion of persons not treated due to undetectable HCV RNA or nongenotype 1 infection, blacks were 65% less likely than nonblacks to be eligible for treatment (28.1% > 17.0%; relative risk, 1.65; 95% confidence interval, 1.46-1.87; P < 0.001). Blacks were more likely to be ineligible due to neutropenia (14% versus 3%, P < 0.001), anemia (7% versus 4%, P = 0.02), elevated glucose (8% versus 3%, P < 0.001), and elevated creatinine (5% versus 1%, P < 0.001). CONCLUSION: Largely due to a higher prevalence of neutropenia and uncontrolled medical conditions, blacks were significantly less likely to be eligible for HCV treatment. Increased access to treatment may be facilitated by less conservative neutrophil requirements and more effective care for chronic diseases, namely, diabetes and renal insufficiency.

Maintenance therapy with peginterferon alfa-2b does not prevent hepatocellular carcinoma in cirrhotic patients with chronic hepatitis C.

BACKGROUND & AIMS: Several studies have reported that low doses of interferon can delay the development of hepatocellular carcinoma (HCC) and progression of chronic hepatitis C. We investigated the incidence of clinical events among participants of the Evaluation of PegIntron in Control of Hepatitis C Cirrhosis (EPIC)3 program. METHODS: Data were analyzed from an open-label randomized study of patients with chronic hepatitis C who had failed to respond to interferon alfa plus ribavirin. All patients had compensated cirrhosis with no evidence of HCC. Patients received peginterferon alfa-2b (0.5 µg/kg/week; n=311) or no treatment (controls, n=315) for a maximum period of 5 years or until 98 patients had a clinical event (hepatic decompensation, HCC, death, or liver transplantation). The primary measure of efficacy was time until the first clinical event. RESULTS: There was no significant difference in time to first clinical event among patients who received peginterferon alfa-2b compared with controls (hazard ratio [HR], 1.452; 95% confidence interval [CI]: 0.880-2.396). There was no decrease in the development of HCC with therapy. The time to disease progression (clinical events or new or enlarged varices) was significantly longer for patients who received peginterferon alfa-2b compared with controls (HR, 1.564; 95% CI: 1.130-2.166). In a prospectively defined subanalysis of patients with baseline portal hypertension, peginterferon alfa-2b significantly increased the time to first clinical event compared with controls (P=.016). There were no new safety observations. CONCLUSIONS: Maintenance therapy with peginterferon alfa-2b is not warranted in all patients and does not prevent HCC. However, there is a potential clinical benefit of long-term suppressive therapy in patients with preexisting portal hypertension.

Efficacy of boceprevir, an NS3 protease inhibitor, in combination with peginterferon alfa-2b and ribavirin in treatment-naive patients with genotype 1 hepatitis C infection (SPRINT-1): an open-label, randomised, multicentre phase 2 trial.

BACKGROUND: Peginterferon plus ribavirin achieves sustained virological response (SVR) in fewer than half of patients with genotype 1 chronic hepatitis C virus infection treated for 48 weeks. We tested the efficacy of boceprevir, an NS3 hepatitis C virus oral protease inhibitor, when added to peginterferon alfa-2b and ribavirin. METHODS: In part 1 of this trial, undertaken in 67 sites in the USA, Canada, and Europe, 520 treatment-naive patients with genotype 1 hepatitis C virus infection were randomly assigned to receive peginterferon alfa-2b 1.5 mug/kg plus ribavirin 800-1400 mg daily for 48 weeks (PR48; n=104); peginterferon alfa-2b and ribavirin daily for 4 weeks, followed by peginterferon alfa-2b, ribavirin, and boceprevir 800 mg three times a day for 24 weeks (PR4/PRB24; n=103) or 44 weeks (PR4/PRB44; n=103); or peginterferon alfa-2b, ribavirin, and boceprevir three times a day for 28 weeks (PRB28; n=107) or 48 weeks (PRB48; n=103). In part 2, 75 patients were randomly assigned to receive either PRB48 (n=16) or low-dose ribavirin (400-1000 mg) plus peginterferon alfa-2b and boceprevir three times a day for 48 weeks (low-dose PRB48; n=59). Randomisation was by computer-generated code, and study personnel and patients were not masked to group assignment. The primary endpoint was SVR 24 weeks after treatment. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00423670. FINDINGS: Patients in all four boceprevir groups had higher rates of SVR than did the control group (58/107 [54%, 95% CI 44-64], p=0.013 for PRB28; 58/103 [56%, 44-66], p=0.005 for PR4/PRB24; 69/103 [67%, 57-76], p<0.0001 for PRB48; and 77/103 [75%, 65-83], p<0.0001 for PR4/PRB44; vs 39/104 [38%, 28-48] for PR48 control). Low-dose ribavirin was associated with a high rate of viral breakthrough (16/59 [27%]), and a rate of relapse (six of 27 [22%]) similar to control (12/51 [24%]). Boceprevir-based groups had higher rates of anaemia (227/416 [55%] vs 35/104 [34%]) and dysgeusia (111/416 [27%] vs nine of 104 [9%]) than did the control group. INTERPRETATION: In patients with untreated genotype 1 chronic hepatitis C infection, the addition of the direct-acting antiviral agent boceprevir to standard treatment with peginterferon and ribavirin after a 4-week lead-in seems to have the potential to double the sustained response rate compared with that recorded with standard treatment alone. FUNDING: Merck.