Trial About Hepatic Security of Antiretroviral Treatment Based on Kaletra Versus Nevirapine in co-Infected HIV/HCV Patients

In retrospective studies, acceleration of hepatic fibrosis has been seen in Nevirapine (NVP) treatment when compared with Protease Inhibitors (PI) boosted with ritonavir treatment in patients with Human Immunodeficiency Virus (HIV) and Hepatitis C Virus (HCV) infection. The high incidence in our country of HIV-HCV co-infection, the availability of a new Kaletra (LPV/r) formulation (more convenient and better tolerated than soft capsules) as well as the possibility of analyzing hepatic fibrosis evolution in a fast and bloodless way, make attractive a study that, in a prospective way, could check the benefits of substituting NVP by LPV/r on hepatic fibrosis in this community.

The prevalence of the HIV-HCV co-infection in Spain is one of the highest because both infections are strongly related to parenteral drugs use; so, from 61 to 69 % of HIV infected patients are also HCV infected.

Acute HCV infection is asymptomatic in 60 to 70% of cases, being the chronification the natural illness evolution. 20% of the patients will develop hepatic cirrhosis after 20 to 30 years of being infected by the HCV. In cirrhosis cases, the hepatocellular carcinoma appears in a rate of 2 to 4% per year, according to studies done with HCV mono-infected patients. Fibrosis progression depends basically on the duration of HCV infection and on the age of infection, but also on other factors, like gender (is faster in men), alcohol consumption (worst over 50 g per day) and HIV co-infection. Several epidemiologist studies have described the negative impact of HIV co-infection, accelerating the progression to cirrhosis and the hepatocarcinoma.

The Highly Active Antiretroviral Treatment (HAART) has a positive impact on survival on co-infected patients, although the three drug families used in HAART can cause hepatic toxicity in this group of patients. Hepatic toxicity appears in 5 to 20% of patients, being more serious and common, but not exclusive, in case of NVP treatment.

On their part, not all PI have the same hepatotoxic profile. An association between serious hepatotoxicity and ritonavir at full strength, indinavir and indinavir plus saquinavir boosted with ritonavir has been found.

As far as fibrosis is concerned, there are studies that show that in HIV/HCV co-infected patients PI-based regimens are associated with a lower progression to fibrosis, while the progression rate to cirrhosis is higher in NVP-based regimens, mainly in those patients with advanced hepatic fibrosis.

Hepatic biopsy is considered the reference test to assess hepatic fibrosis, nevertheless it is an invasive, painful and with a low but potentially serious risk for the patient's life. Moreover, the viability of a hepatic biopsy can be doubted due to sampling error or interobservation variability. For that reason, several biochemist tests have been developed to reflect the hepatic fibrosis extent or stage in a reliable way. Recently a hepatic rigidity measure through elastography has been presented as a non-invasive and very promising method to assess hepatic fibrosis.