Worldwide, the hepatitis C virus genotype 1 (HCV GT-1) accounts for an estimated 160 million chronic infections, and human immunodeficiency virus (HIV) for an estimated 40 million. As the transmission routes are shared by both infections, there are an estimated 5 million chronic HIV and HCV co-infection cases worldwide. These patients experience more rapid liver disease progression and a lack of response to interferon treatments.
During the 21st Conference on Retroviruses and Opportunistic Infections (CROI) this week in Boston, Douglas Dieterich, representing the Mount Sinai School of Medicine, presented data from the open-label STARTVerso4 study sponsored by Boehringer Ingelheim. This is an ongoing Phase III clinical trial, evaluating the safety and efficacy of Faldaprevir (FDV) plus pegylated interferon α-2a (Pegasys) and ribavirin in patients co-infected with HCV GT-1 and HIV.
The 308 participants were mostly European and North American males, with an average age of 47 years with both the HIV and HCV GT1 co-infection. A high proportion of the population presented a difficult-to-treat HCV infection (79% HCV subtype GT-1a, 15% cirrhosis, 82% high baseline HCV RNA). The patients had a high CD4 cell count (enough to not yet need HIV treatment) or were in stable antiretroviral therapy (ART) without relevant interactions with Faldaprevir to be considered for treatment.
All participants were treated with FDV once a day, plus Pegasys and ribavirin in a weight-based treatment. The FDV doses were dependent on the HIV current medication of the participants; patients taking HIV protease inhibitors received 120mg FDV per 24 weeks; patients taking efavirenz took 240 mg FDV for either 12 or 24 weeks; and those taking raltegravir or not on ART were randomized to one of the previous groups. Depending on the early treatment success (ETS) patients were randomized to either stop all drugs at week 24 or continue pegylated interferon/ribavirin alone through week 48.
SVR4 was achieved by 74% of patients; it’s rates were comparable across FDV doses and durations of treatment. SVR4 rates were high in all patients, regardless of the difficult-to-treat HCV infections. The FDV combination therapy was well tolerated; the majority of side-effects were related to interferon-based therapy.
Douglas Dieterich concluded that Faldaprevir was effective and well tolerated in difficult-to-treat patients co-infected with HVC GT-1 and HIV, very similar to the observed in HCV GT-1 mono-infected patients.