07/19/10

PRN Report from AIDS 2010:  RAL+LPV/r Shown to be Non-inferior to TDF+FTC+LPV/r in Treatment Naive

Current guidelines for combination antiretroviral therapy include the use of NRTIs, however 15-20% of patients with long term NRTI use experience drug-related toxicity (Riddle SA, NEJM 2008;358:2095-2106). Jacques Reynes presented the 48week results today of PROGRESS, the first phase III study designed to test efficacy and safety of a nucleoside sparing regimen using raltegravir and lopinavir/ritonavir in treatment naïve patients.

In this study, 206 treatment naïve patients, with HIV-1 RNA >1000 copies/ml were randomly assigned to either LPV/r + raltegravir 400mg bid or to LPV/r + tenofovir/emtricitabine 300mg/200mg fixed dose combination. The primary efficacy endpoint was ITT TLOVR at week 48. At this endpoint the two groups showed similar virologic responses with 83.2% of the raltegravir group and 84.8% of the TDF/FTC group achieving HIV-1 RNA <40 copies/ml. The two groups experienced increases of 214.9 cells/mm3 and 245.0 cells/mm3 respectively (p=0.85).

Adverse effects were similar with 1 patient receiving raltegravir experienced a RAL-associated mutation N155H, 1 patient on TDF/FTC experienced M184V mutation. There were no protease-associated mutations in either group. Laboratory abnormalities were noted with higher CPK in the RAL group (12.9% vs. 3.8%, p=0.023) as well as greater mean increases in total cholesterol, triglycerides and HDL in the RAL group.

In summary, the NRTI-sparing regimen of LPV/r + raltegravir appeared to be well tolerated and non-inferior compared with LPV/r + TDF/FTC, raising the possibility of a viable option for patients experiencing NRTI-related toxicities.


Reference:
Reynes J, Lawal A, Pulido F, et al. Lopinavir/ritonavir combined with raltegravir demonstrated similar antiviral efficacy and safety as lopinavir/ritonavir combined with tenofovir disoproxil fumarate/emtricitabine in treatment-naïve HIV-1 infected subjects. Presented July 19 at the XVIII International AIDS Conference, Vienna, Austria. Oral Abstract MOAB0101.

Source: Reporting from Vienna, Austria for PRN News: Anita Radix MD, MPH and Susan Weiss FNP, AAHIVS