Impact of Antiretroviral Therapy on Metabolic, Skeletal, and Cardiovascular Parameters

The U.S. Department of Health and Human Services (HHS) guidelines recommend that HIV-infected people who have never received anti-HIV therapy be treated with a triple drug regimen (commonly called combination antiretroviral therapy, cART). Since the introduction of cART, morbidity and mortality among HIV-infected patients has been dramatically reduced. However, metabolic, skeletal, and cardiovascular diseases have been increasingly reported among HIV-infected patients and may be attributable, in part, to the direct effects of cART. Much of our understanding of the development of these diseases, risk factors, and consequences of these disorders has been derived from clinical studies of HIV-infected persons receiving older antiretroviral agents. A5260s was designed to examine the contributions of HIV-disease related factors and impact of newer antiretroviral drugs on the development of metabolic (such as blood vessels, blood sugar, cholesterol), skeletal, and cardiovascular diseases in people who have never received anti-HIV therapy. A5260s is a prospective substudy of a phase III randomized clinical trial A5257 (see ClinicalTrials.gov identifier: NCT00811954). A5257 was designed to look at different combinations of anti-HIV drugs that do not contain the medication efavirenz (EFV) and how well these drug combinations work to decrease the amount of HIV in the blood and to allow immune system recovery in people who have never received anti-HIV therapy. A5257 also examined drug tolerability and safety for the various drug combinations.

A5260s is the optional, metabolic substudy of a phase III, prospective, randomized clinical trial (A5257). For complete details about the parent study A5257, please see ClinicalTrials.gov identifier NCT00811954. Some participants in study A5257 were asked to participate in substudy A5260s. Not all participants were asked since A5260s only took place at a subset of A5257 sites. Participants who agreed to participate in substudy A5260s were enrolled at the same time as their enrollment in A5257. No interventions were given as part of A5260s, but all A5260s participants underwent blood draws, self-administered questionnaire responses (related to physical activity and body image), ultrasound scans to measure the thickness of the carotid artery in the neck and brachial artery flow mediated dilation in the arm, and computerized topography (CT) and dual-energy x-ray absorptiometry (DEXA) scans to measure bone mineral density and body fat. The duration of A5260s study was between 2 and 3 years (96 and 144 weeks), depending on when the participant enrolled. The study was designed to enroll a total of 330 participants with at least 110 per a group; each group represented a different randomized drug combination as defined and assigned by the main study A5257. Cohort A: Atazanavir (ATV) + Ritonavir (RTV) + Emtricitabine/tenofovir disoproxil fumarate (FTC/TDF) Cohort B: Raltegravir (RAL) + FTC/TDF Cohort C: Darunavir (DRV) + RTV + FTC/TDF All participants were asked to return for A5260s clinic visits at weeks 4, 24, 48 96 and 144 and participated in all clinical evaluations. No clinical evaluation was restricted to a subset of A5260s participants. If a participant chose to discontinue participation in the substudy, the participant was able to continue in study A5257. However, a participant discontinuing participation from A5257 was also removed from A5260s. Additionally, a participant's decision to discontinue or switch study drugs in the main study did not impact participation and follow-up clinic visits in A5260s.