Similar response rates shown with rilpivirine, efavirenz in HIV

Cohen C. J Acquir Immune Defic Syndr. 2012;doi:10.1097/QAI.0b013e31824d006e.

Issue: March 2012

Rilpivirine and efavirenz had comparable response rates at 48 weeks. However, rilpivirine demonstrated increased virologic failure and was better tolerated when compared with efavirenz.

The study was a pooled analysis of the ECHO and THRIVE trials, which were both phase 3, double blind, double dummy trials comparing 25 mg once-daily rilpivirine (Edurant, Tibotec) with 600 mg once-daily efavirenz (Sustiva, Bristol-Myers Squibb). The primary endpoint in both trials was a confirmed response (viral load, 50 copies/mL) at week 48.

Confirmed response rates were 84% for those assigned rilpivirine and 82% for those assigned efavirenz; and the incidence of virologic failure was 9% in the rilpivirine group vs. 5% in the efavirenz group.

A higher baseline viral load and suboptimal adherence to treatment was related to lower response rates, higher virologic failure and development of resistance among both groups. The CD4+ cell count increased over time in both groups.

Adverse events were less frequent in those who received rilpivirine. In the rilpivirine group, 3% of participants experienced adverse events leading to discontinuation vs. 8% in the efavirenz group.

“Treatment success in patients with HIV-1 is achieved through a combination of virologic suppression and the patient’s ability to tolerate treatments,” the researchers wrote. “Overall, rilpivirine had a more favorable tolerability profile than efavirenz with fewer treatment discontinuations. The rate of virologic failures was low in both treatment groups while numerically higher for rilpivirine, but still within the ranges described in antiretroviral trials performed recently in treatment-naive HIV-infected patients.”

Disclosure: Dr. Cohen has received research funding from Bristol-Myers Squibb (BMS), Gilead Sciences, Merck, Tibotec, Tobira and ViiV Healthcare. He is on advisory boards for BMS, Gilead Sciences, Merck, Tibotec and Tobira. He has received speaker honoraria from BMS, Gilead Sciences, Merck and Tibotec before January 2011. Dr. Molina has acted as a consultant, participated in advisory boards, has received speakers’ fees and has been an investigator for clinical trials for Abbott, BMS, Boehringer Ingelheim (BI), Gilead Sciences, Merck, Sharp and Dohme (MSD), Tibotec and ViiV Healthcare. Dr. Cahn has received grant research support, advisory and speakers’ fees from Abbott, Avexa, BI, Gilead Sciences, GlaxoSmithKline (GSK), Janssen, Merck, Tibotec and ViiV Healthcare. Dr. Clotet has received research funding, consultancy fees, or lecture sponsorships from, or has served on advisory boards for Abbott, BI, Gilead Sciences, GSK, Janssen-Cilag, MSD, Pfizer and ViiV Healthcare. Dr. Grinsztejn has participated in advisory boards, has received speakers’ fees and has been an investigator for clinical trials for BMS, MSD, Tibotec and ViiV Healthcare. Dr. Johnson has received honoraria from Abbott, BMS, GSK, MSD, Tibotec and ViiV Healthcare. Dr. Saag has received consulting fees and/or research support from BI, BMS, GSK, Merck, Pain Therapeutics, Pfizer, Tibotec/J&J, Vertex and ViiV Healthcare. Drs. Crauwels, Rimsky, Vanveggel and Boven, and Mr. Williams are full-time employees of Tibotec. Dr. Lefebvre was previously a full-time employee of Janssen.

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