The objective of this prospective, multicenter, observational study was to evaluate healthcare for hepatitis C virus (HCV)-infected drug abusers in France and to determine predictors of successful therapeutic intervention. A total of 170 drug users were recruited from 40 French centers. Three centers recruited 66 participants (38.8%), and one to eight patients each were enrolled from 37 other centers (n=104). A sustained viral response (SVR) was seen in 65 (38.2%) patients. SVR rates were significantly higher in compliant than in non-compliant patients (43.5% versus 23.9%; P=0.019), in patients from high- rather than low-recruiting centers (54.5% versus 27.9%; P<0.001) and in patients receiving Buprenorphine rather than methadone (48.1% versus 21.8%; P=0.001). In patients, who completed both the treatment and follow-up (n=94), SVR rate was 57.4%. Buprenorphine substitution therapy and genotypes 2 or 3 HCV infection were associated with significantly higher rates of SVR (P<0.01, for both comparisons). In conclusion, successful care of hepatitis requires an active treatment policy of every center toward drug addicts. Additional studies are needed to explore the difference in SVR with methadone versus Buprenorphine therapy.