The investigators aim at investigating the efficacy of grazoprevir/elbasvir ±ribavirin in HIV-positive MSM participating in the SHCS in a broader setting of coinfected MSM. The study pursues a comprehensive approach of a treat, counsel and cure strategy exploring the impact of such a strategy in a representative HIV/HCV-coinfected MSM population. This study is a nested project of the Swiss HIV Cohort Study entitled "The Swiss HCVree Trial".