Two important HIV HCV coinfection phase 2 studies of HCV protease inhibitor therapy in combination with PEG-IFN and ribavirin for HCV genotype 1 were presented today with SVR12 data (sustained virological response 12 weeks after treatment cessation) available. Both studies found approximately 30% higher response rates (a marked advance in this patient group), but there were some caveats.

Abstract 46 (presented by Doug Dieterich) reported that Telaprevir with PEG-IFN-alpha-2a and ribavirin had higher SVR12 rates than with PEG-IFN-alpha-2a and ribavirin alone (74 vs 45%).

Abstract 47 (presented by Mark Sulkowski) examined Boceprevir with PEG-IFN-alpha-2b and ribavirin (n=64) which was compared with PEG-IFN-alpha-2b and ribavirin in people with genotype 1 HCV infection with significant differences in SVR12 (61 vs 27%).

The sample sizes were small (less than 100) and both studies reveal expected toxicity profiles with the addition of the HCV protease inhibitor.

Other data presented at the conference revealed the very significant drug-drug interactions (including with many HIV drugs) with these compounds that will mean that their use will need careful thought. Jurgen Rockstroh summarised the state of play with these agents in abstract 72 and suggested management strategies based on the current evidence.

The therapeutic outlook for people with HIV and HCV coinfection looks much more promising with these early data and phase 3 studies in progress or planned and a number of new HCV agents in the pipeline. Watch this space.