First-wave protease inhibitors for hepatitis C genotype 1 treatment: a real-life experience in Brazilian patients

Abstract INTRODUCTION: Licensed for chronic hepatitis C treatment in 2011, the protease inhibitors (PIs) telaprevir (TVR) and boceprevir (BOC), which have high sustained viral responses (SVR), ushered a new era characterized by the development of direct-action drugs against the hepatitis C virus (HCV). The aim of this study was to analyze the effectiveness and safety of BOC and TVR administered with pegylated interferon and ribavirin and to share the experience of a Brazilian reference center. METHODS: A retrospective descriptive study was conducted in patients with HCV genotype 1 infection who started treatment between July 2013 and December 2015. Data were collected using a computerized system. RESULTS: A total of 115 subjects were included, of which 58 (50.4 %) had liver cirrhosis and 103 (89.6 %) used TVR. The overall SVR rate was 61.7 % (62.1 % for TVR and 58.3 % for BOC). The presence of cirrhosis was associated with a lower SVR rate, whereas patients who relapsed after prior therapy had a greater chance of showing SVR than did non-responders. The incidence of adverse drug reactions (ADRs) was high. Almost all patients (~100 %) presented with hematologic events. Furthermore, treatment had to be discontinued in 15 subjects (13 %) due to severe ADRs. CONCLUSIONS: In conclusion, the SVR rates in our study were lower than those reported in pre-marketing studies but were comparable to real-life data. ADRs, particularly hematological ADRs, were more common compared to those in previous studies and resulted in a high rate of treatment discontinuity.

Effectiveness of first-wave protease inhibitors in hepatitis C virus genotype 1 infection: a multicenter study in Brazil

Abstract INTRODUCTION: In 2013, combination therapy using peginterferon, ribavirin, and boceprevir or telaprevir was introduced to treat hepatitis C virus genotype 1 infection in Brazil. The effectiveness of this therapy in four Brazilian regions was evaluated. METHODS: Clinical and virological data were obtained from patients of public health institutions in five cities, including sustained virological response (SVR) and side effects. Patients with advanced fibrosis (F3/4), moderate fibrosis (F2) for > 3 years, or extra-hepatic manifestations were treated according to Ministry of Health protocol. Treatment effectiveness was verified by using bivariate and multivariate analysis; p-values of < 0.05 were considered significant. RESULTS: Of 275 patients (64.7% men; average age, 57 years old), most (61.8%) were treatment-experienced; 53.9% had subgenotype 1a infection, 85.1% had advanced fibrosis, and 85.5% were treated with telaprevir. SVR was observed in 54.2%. Rapid virological response (RVR) was observed in 54.6% of patients (data available for 251 patients). Overall, 87.5% reported side effects and 42.5% did not complete treatment. Skin rash, severe infection, and death occurred in 17.8%, 2.5%, and death in 1.4% of cases, respectively. SVR was associated with treatment completion, RVR, and anemia. CONCLUSIONS: The effectiveness of hepatitis C virus triple therapy was lower than that reported in phase III clinical trials, possibly owing to the prioritized treatment of patients with advanced liver fibrosis. The high frequency of side effects and treatment interruptions observed supported the decision of the Brazilian authorities to suspend its use when safer and more effective drugs became available in 2015.

Effectiveness and safety of first-generation protease inhibitors in real-world patients with hepatitis C virus genotype 1 infection in Brazil: a multicenter study

OBJECTIVE: To evaluate the effectiveness and safety of first-generation protease inhibitors for the treatment of genotype 1 hepatitis C virus-infected patients at Brazilian reference centers. METHODS: This multicenter cross-sectional study included hepatitis C virus genotype 1 monoinfected patients treated with Peg-interferon, ribavirin, and either boceprevir (n=158) or telaprevir (n=557) between July 2013 and April 2014 at 15 reference centers in Brazil. Demographic, clinical, virological, and adverse events data were collected during treatment and follow-up. RESULTS: Of the 715 patients, 59% had cirrhosis and 67.1% were treatment-experienced. Based on intention-to-treat analysis, the overall sustained viral response was 56.6%, with similar effectiveness in both groups (51.9% for boceprevir and 58% for telaprevir, p=0.190). Serious adverse events occurred in 44.2% of patients, and six deaths (0.8%) were recorded. Cirrhotic patients had lower sustained viral response rates than non-cirrhotic patients (46.9% vs. 70.6%, p<0.001) and a higher incidence of serious adverse events (50.7% vs. 34.8%, p<0.001). Multivariate analysis revealed that sustained viral response was associated with the absence of cirrhosis, viral recurrence after previous treatment, pretreatment platelet count greater than 100,000/mm3, and achievement of a rapid viral response. Female gender, age>65 years, diagnosis of cirrhosis, and abnormal hemoglobin levels/platelet counts prior to treatment were associated with serious adverse events. CONCLUSION: Although serious adverse events rates were higher in this infected population, sustained viral response rates were similar to those reported for other patient cohorts.

Predictors of early treatment discontinuation and severe anemia in a Brazilian cohort of hepatitis C patients treated with first-generation protease inhibitors

The aim of this study was to determine risk factors for adverse events (AE)-related treatment discontinuation and severe anemia among patients with chronic hepatitis C virus (HCV) genotype 1 infection, treated with first-generation protease inhibitor (PI)-based therapy. We included all patients who initiated treatment with PI-based therapy at a Brazilian university hospital between November 2013 and December 2014. We prospectively collected data from medical records using standardized questionnaires and used Epi Info 6.0 for analysis. Severe anemia was defined as hemoglobin ≤8.5 mg/dL. We included 203 patients: 132 treated with telaprevir (TVR) and 71 treated with boceprevir (BOC). AE-related treatment discontinuation rate was 19.2% and anemia was the main reason (38.5%). Risk factors for treatment discontinuation were higher comorbidity index (OR=1.85, CI=1.05-3.25) for BOC, and higher bilirubin count (OR=1.02, CI=1.01-1.04) and lower BMI (OR=0.98, CI=0.96-0.99) for TVR. Severe anemia occurred in 35 (17.2%) patients. Risk factors for this outcome were lower estimated glomerular filtration rate (eGFR; OR=0.95, CI=0.91-0.98) for patients treated with TVR, and higher comorbidity index (OR=2.21, CI=1.04-4.67) and ribavirin dosage (OR=0.84, CI=0.72-0.99) for those treated with BOC. Fifty-five (57.3%) patients treated with TVR and 15 (27.3%) patients treated with BOC achieved sustained virological response (SVR). Among patients who received TVR and interrupted treatment due to AE (n=19), only 26.3% (n=5) achieved SVR (P=0.003). Higher number of comorbidities, lower eGFR and advanced liver disease are associated with severe anemia and early treatment cessation, which may compromise SVR achievement.

Acute pancreatitis associated with boceprevir: a case report

Approximately 170 million people are infected with hepatitis C, and the sustained virological response rate to treatment with pegylated interferon and ribavirin is 30-50%. In an attempt to improve the chances of cure, boceprevir is being added to therapy, but it is associated with an increased incidence of adverse events. We herein report a case of acute pancreatitis developed during treatment with pegylated interferon, ribavirin and boceprevir. Boceprevir was the most likely cause of drug-associated pancreatitis after the most common causes were ruled out, since this adverse event had not occurred when the patient had previously been exposed to pegylated interferon and ribavirin and there was no recurrence of the episode of pancreatitis when these two drugs were reintroduced. Acute pancreatitis is a rare adverse event associated with boceprevir therapy, but a potentially fatal event. Sequential determination of pancreatic enzymes should be considered during hepatitis C treatment with boceprevir.