Efficacy and safety of raltegravir plus lamivudine maintenance therapy

Decreasing medication burden with raltegravir plus lamivudine in virologically suppressed persons with HIV (PWH) maintained efficacy and was well tolerated at 24 weeks, but more comprehensive data over longer follow-up are required.

Prospective 48 week extension phase of the raltegravir plus lamivudine arm from a previous 24 week pilot randomized clinical trial in which virologically suppressed PWH were randomized 2:1 to switch to fixed-dose combination 150 mg lamivudine/300 mg raltegravir twice daily or to continue therapy. In this 48 week extension phase, raltegravir was dosed at 1200 mg/day and lamivudine 300 mg/day. Primary outcome was the proportion of PWH with treatment failure at Week 48. Secondary outcomes were changes in ultrasensitive plasma HIV RNA, HIV DNA in CD4 cells, serum IL-6, ultrasensitive C-reactive protein and sCD14, body composition, sleep quality, quality of life and adverse effects.

Between May 2018 and June 2019, 33 PWH were enrolled. One participant experienced virological failure without resistance mutations and re-achieved sustained virological suppression without therapy discontinuation, and two others discontinued therapy due to adverse effects. Treatment failure was 9% (95% CI 2%-24%) and 3% (95% CI 0%-17%) in the ITT and on-treatment populations. There were significant changes between baseline and Week 48 in serum cytokines but not in other secondary outcomes.

Switching to raltegravir and lamivudine in PWH with virological suppression maintains efficacy and is well tolerated. This maintenance regimen might be a cost-effective option for PWH at risk of drug-drug interactions or needing to avoid specific toxicities of certain antiretroviral drugs or their negative impact on comorbidities.