AIM:To assess,in a routine practice setting,the sus-tained virologic response(SVR) to telaprevir(TPV) or boceprevir(BOC) in hepatitis C virus(HCV) nullresponders or relapsers with severe liver fibrosis.METHODS:One hundred twenty-five patients were treated prospectively for 48 wk with TPV or BOC + pegylated-interferon(peg-INF) α2a + ribavirin(PR) according to standard treatment schedules without randomization.These patients were treated in routine practice settings in 10 public or private health care centers,and the data were prospectively collected.Only patients with severe liver fibrosis(Metavir scores of F3 or F4 upon liver biopsy or liver stiffness assessed by elastography),genotype 1 HCV and who were null-responders or relapsers to prior PR combination therapy were included in this study.RESULTS:The Metavir fibrosis scores were F3 in 35(28%) and F4 in 90(72%) of the patients.In total,62.9% of the patients were null-responders and 37.1% relapsers to the previous PR therapy.The overall SVR rate at 24 wk post-treatment withdrawal was 59.8%.The SVR was 65.9% in the TPV group and 44.1% in the BOC group.Independent predictive factors of an SVR included a response to previous treatment,relapsers vs null-responders [OR = 3.9;(1.4,10.6),P = 0.0084],a rapid virological response(RVR) [OR 6.9(2.6,18.2),P = 0.001] and liver stiffness lower than 21.3 kPa [OR = 8.2(2.3,29.5),P = 0.001].During treatment,63 patients(50.8%) had at least one severe adverse event(SAE) of grade 3 or 4.A multivariate analysis identified two factors associated with SAEs:female gender [OR = 2.4(1.1,5.6),P = 0.037] and a platelet count below 150 × 103/ mm3 [OR = 5.3(2.3,12.4),P ≤ 0.001].CONCLUSION:More than half of these difficult-to-treat patients achieved an SVR and had SAEs in an actual practice setting.The SVR rate was influenced by the response to previous PR treatment,the RVR and liver stiffness. AIM: To assess, in a routine practice setting, the sus-tained virologic response (SVR) to telaprevir (TPV) or boceprevir (BOC) in hepatitis C virus (HCV) nullresponders or relapsers with severe liver fibrosis. METHODS: One hundred twenty -five patients were treated prospectively for 48 wk with TPV or BOC + pegylated-interferon (peg-INF) α2a + ribavirin (PR) according to standard treatment schedules without randomization. These patients were treated in routine practice settings in 10 public or private health care centers, and the data were prospectively collected. Patients with severe liver fibrosis (Metavir scores of F3 or F4 upon liver biopsy or liver stiffness assessed by elastography), genotype 1 HCV and who were null-responders or relapsers to prior PR combination therapy RESULTS: The Metavir fibrosis scores were F3 in 35 (28%) and F4 in 90 (72%) of the patients. In total, 62.9% of the patients were null-responders and 37.1% relapsers to the previous PR therapy. over all SVR rate at 24 wk post-treatment withdrawal was 59.8%. The SVR was 65.9% in the TPV group and 44.1% in the BOC group. dependent predictor factors of an SVR included a response to previous treatment, relapsers vs null-responders [ OR = 3.9; (1.4,10.6), P = 0.0084], a rapid virological response (RVR) [OR 6.9 (2.6,18.2), P = 0.001] and liver stiffness lower than 21.3 kPa [OR = 8.2 (50.8%) had at least one severe adverse event (SAE) of grade 3 or 4. A multivariate analysis identified two factors associated with SAEs: female gender [OR = 2.4 (1.1 , 5.6), P = 0.037] and a platelet count below 150 × 10 3 / mm 3 [OR = 5.3 (2.3,12.4), P ≤ 0.001] .CONCLUSION: More than half of these difficult-to-treat patients achieved an SVR and had SAEs in an actual practice setting. The SVR rate was influenced by the response to previous PR treatment, the RVR and liver stiffness.