(P40) Real-world effectiveness of elbasvir/grazoprevir in the treatment of patients with hepatitis C virus genotype 1a infection in Norway


Rafael A. Leiva1, Bente M. Bergersen2, Ane-Kristine Finbråten3, Per Kristian Sandvei4, Øystein Simonsen4, Carola Rosseland5, Lital Young6, Yngve Mikkelsen7,  Ravinder Singh5, Olav Dalgard8


1 Haukeland University Hospital, Norway, 2 Oslo University Hospital Ullevål, Norway, 3 Lovisenberg Diaconal Hospital, Norway, 4 Hospital Østfold Kalnes, Norway, 5 MSD Norway, 6 MSD Switzerland, 7 LINK Medical AS, Norway, 8 Akershus University Hospital,  Norway


Background and aims
In Europe, recommended treatment duration of genotype 1a (GT1a) with Elbasvir/grazoprevir (EBR/GZR) is 12 weeks but considering 16 weeks with ribavirin if resistance-associated substitutions (RAS) has been detected and/or if the patient has a high viral load at baseline. In Norway, many clinicians have chosen to pragmatically treat all GT1a-infected patients using 12 weeks of EBR/GZR without ribavirin, regardless of viral load and baseline RAS testing. The primary objective of this study is to evaluate the real-world effectiveness of 12 weeks EBR/GZR treatment without ribavirin and baseline RAS testing in a Norwegian cohort of patients with HCV GT1a.
This is a retrospective, observational cohort study utilizing computerized databases and electronic medical journals at five Norwegian HCV clinics that did not systematically offer RAS testing at baseline. We included consecutive adult patients with chronic HCV GT1a and compensated liver disease who received 12 weeks of EBR/GZR without ribavirin and baseline RAS testing and without consideration of baseline viral load. Only patients with available HCV RNA data at least 4 weeks post-treatment were included. Cirrhosis was defined by liver stiffness measurement of 12.5 kPa or an APRI score > 2. The main end-point was sustained virologic response at week 12 (SVR12), or if not available, SVR4.
We included 163 patients of whom 60.7 % were male and median age was 49 years (26 -73 years). HIV coinfection was present in 9.4% (15/160) and cirrhosis in 1.8% (3/163). The viral load was > 800 000 IU/ml in 44.2 % (69/156) of patients. SVR was achieved in 96.6% (144/149) patients (140 patients tested 12 weeks post-treatment and 4 patients 4 weeks post-treatment). Five patients experienced virological failure. SVR was achieved in 98.6 % (71/72) of those with viral load <800 000 IU/ml and 94 % (63/67) of those with viral load ≥800 000 IU/ml. At the time of abstract submission, data from two clinics were analysed, data from three more clinics will be added at a later time point.
In Norway, patients with HCV GT1a infection achieved high cure rates using 12 weeks of EBR/GZR without ribavirin, baseline RAS testing and without regards to baseline viral load.