New subgroup analyses from the phase 3 EMERALD trial are supporting the safety and efficacy of switching treatment-experienced, virally suppressed patients to the therapy.
The approval of Symtuza (darunavir 800 mg, cobicistat 150 mg, emtricitabine 200 mg, and tenofovir alafenamide 10 mg) for the treatment of HIV in July 2018 was based on positive data coming from the AMBER and EMERALD trials. Since then, more data coming from the trials have reaffirmed the safety and efficacy of the treatment, and now new subgroup analyses from EMERALD are supporting the safety and efficacy of switching certain patients to the regimen.
Data from over 1000 patients across 48 weeks of treatment showed that, for treatment-experienced, virally suppressed patients, switching to the regimen is highly safe and effective, regardless of patient characteristics, prior treatment, and antiretroviral regimen at baseline.
The regimen is the first darunavir-based single-tablet treatment regimen that combines darunavir, which has demonstrated higher barrier to resistance, and tenofovir alafenamide, which has been shown to lower the risk of renal and bone toxicities compared with disoproxil fumarate.
The subgroup included 763 patients switching to treatment with Symtuza and 378 patients remaining on treatment with a boosted protease inhibitor plus emtricitabine/tenofovir disoproxil fumarate regimen, who served as a control group. All patients were virally suppressed. According to the researchers, the group was more reflective of the real world than other recent switch studies.
Between the 2 groups, virologic rebound rates were similar, with a rebound rate of 2.5% among the Symtuza group and a rebound rate of 2.1% among the control group. Virologic response rates were high and ranged from 91% to 97% for those switching to Symtuza and ranged from 89% to 99% for those in the control group.
Both virologic rebound rates and virologic response rates for patients aged under 50 years without polypharmacy and patients aged over 50 years with polypharmacy fell within these ranges, leading the researchers to suggest the efficacy of Symtuza was not impacted by patient characteristics, prior treatment experience, or antiretroviral regimen at the time of treatment switch.
“Furthermore, changes in lipid parameter values through week 48 did not vary by demographic characteristics and, as previously described, low proportions of patients initiated lipid-lowering therapy during the study, with no significant differences between treatment arms,” added the researchers.
Consistent with prior switch studies, rates of adverse events were low for both groups, although there was a higher proportion of patients with at least 1 study drug-related adverse event in the Symtuza group. The most common study drug-related adverse events were diarrhea and osteopenia, which presented in 1% to 2% of patients.
Huhn G, Eron J, Girard P, et al. Darunavir/cobicistat/emtricitabine/tenofovir alafenamide in treatment-experienced, virologically suppressed patients with HIV-1: subgroup analyses of the phase 3 EMERALD study [published online August 29, 2019]. AIDS Res Ther. doi:10.1186/s12981-019-0235-1.