Pioglitazone for Hepatic Steatosis in HIV/HCV Co-infection

Following the introduction of effective antiretroviral therapy for HIV, the management of co-morbidities such as hepatitis C virus (HCV) has taken on increasing significance in the care and health maintenance of chronically infected patients. HCV co-infection is common in HIV, with an estimated prevalence of 30 percent among HIV-infected adults in the US. Further, the reported prevalence of hepatic steatosis in HIV/HCV co-infection is between 40-67 percent.

In recent years, the significance of hepatic steatosis and accompanying insulin resistance in HCV has gained increasing recognition. For example, steatosis is associated with increased rates of necro-inflammatory change and fibrosis in HIV/HCV co-infected patients. Furthermore, studies showed that, among non-HIV infected HCV patients, the presence of steatosis and/or insulin resistance was associated with poorer response to HCV therapy. These observations have led to research interest in treating hepatic steatosis in HCV, particularly in the context of pegylated interferon and ribavirin therapy.

Administration of the thiazolidinedione, pioglitazone, leads to significant reductions in hepatic steatosis, inflammation and in some cases fibrosis in patients with non-alcoholic steatohepatitis (NASH). Therefore, the potential benefits of pioglitazone therapy in the setting of HIV/HCV co-infection and hepatic steatosis will be determined. The proposed study is a 48-week, double-blind, randomized placebo-controlled trial of pioglitazone (45 mg/day) in 50 HIV/HCV-infected men and women. After the 48-week randomized portion of the trial, all participants will enter a 48-week open treatment extension arm irrespective of original randomization. It is anticipated that 100 subjects will be needed to be screened to identify a sufficient number of eligible participants to enroll in the study.

The primary outcome variable of interest in this trial will be the change in hepatic fat content measured by magnetic resonance (MR) spectroscopy. Important secondary outcomes will be histologic improvement on liver biopsy performed at baseline and 48 weeks, as well as improvements in transaminase levels and insulin resistance. The open treatment extension will allow all participants an opportunity to receive active study medication and it will allow the potential benefits of additional pioglitazone therapy to be assessed. In this way, important information about the efficacy of pioglitazone to treat hepatic steatosis and improve the metabolic profile in HIV/HCV co-infected patients will be obtained.