Is Symtuza the One-Pill Regimen You're Looking For?

At last week’s 16th European AIDS Conference in Milan, Italy, Professor Chloe Orkin of the Royal London Hospital reported the findings of the AMBER Phase 3 study — which was designed to evaluate the safety and efficacy of Symtuza in previously untreated people living with HIV, reports NAM aidsmap.

Orkin, one of the study’s authors, said the research showed that the single-pill combination of darunavir, cobicistat, tenofovir alafenamide and emtricitabine (marketed as Symtuza) is just as effective as a multi-pill combination of darunavir, cobicistat, emtricitabine and the older formulation of tenofovir (tenofovir disoproxil) in previously untreated people with HIV.

This combination of darunavir, cobicistat, tenofovir alafenamide and emtricitabine has already been approved and is in use as an HIV treatment in Europe, but is still awaiting approval by the Food and Drug Administration for use in the U.S..

Details of the Study

The study recruited 725 participants in Europe and North America, predominantly male (88 percent) and white (83 percent) with a median baseline viral load of 4.5 log10 copies/ml (31,600 copies/ml) and median CD4 cell count of 453 cells/mm3. Seven percent had CD4 counts below 200 cells/mm3 and 18 percent had viral loads above 100,000 copies/ml.

Participants were randomized equally to receive Symtuza or the control arm regimen. After 48 weeks of treatment, 91.4 percent of the Symtuza group had viral loads below 50 copies/ml, compared to 88.4 percent of the control group. These results prove that Symtuza is as effective, if not more so, in suppressing one’s viral load as the standard multi-pill treatment.

Virologic failure occurred in 4.4 percent of the Symtuza group and 3.3% of the control group. No participant experiencing virological rebound developed resistance to darunavir or tenofovir; one developed resistance to emtricitabine.

Baseline drug resistance testing found a high prevalence of mutations associated with resistance to the non-nucleoside reverse transcriptase inhibitor drug class (16.3 percent) suggesting substantial onward transmission of drug-resistant virus. At least one mutation associated with protease inhibitor resistance was present in 2.1 percent of participants at baseline.

Discontinuations due to adverse reactions occurred less frequently in the Symtuza group (only 1.9 percent versus 4.4 percent in the control arm) although the incidence of serious adverse events and grade 3-4 adverse events was similar in the two study arms. The most common adverse events were diarrhea, rash and nausea.

Click here for the complete results of the study.