Efficacy, Safety of Fixed-Dose HIV Regimen With Bictegravir Evaluated
Bictegravir in combination with FTC/TAF is also being evaluated in 2 ongoing studies.
Gilead announced results from 2 Phase 3 studies for the investigational fixed-dose combination oF bictegravir 50mg (BIC), a novel integrase strand transfer inhibitor, and emtricitabine 200mg (FTC)/tenofovir alafenamide 25mg (TAF), a dual-NRTI backbone, in the treatment of treatment-naive adults with HIV. The data were presented at the 9th International AIDS Society (IAS) Conference on HIV Science in Paris, France.
In Study 1489, treatment-naive adults with HIV (n=629) were randomized to receive either BIC/FTC/TAF or abacavir/dolutegravir/lamivudine (600/50/300mg) (ABC/DTG/3TC). At Week 48, BIC/FTC/TAF was found to be statistically non-inferior to ABC/DTG/3TC with 92.4% of patients in BIC/FTC/TAF group and 93.0% of patients in the ABC/DTG/3TC group achieving the primary endpoint of HIV-1 RNA levels <50 copies/mL (difference –0.6%, 95% CI: –4.8 to 3.6%; P =.78). With regards to changes in bone mineral density (BMD), the mean percentage changes from baseline for BIC/FTC/TAF vs ABC/DTG/3TC were –0.83% and –0.60%, respectively. An analysis of renal function showed no differences between the treatments in changes from baseline for estimated glomerular filtration rate or proteinuria.
“Combinations of an integrase inhibitor plus a dual-NRTI backbone have become a standard of care for initial treatment of HIV. In clinical trials, the investigational regimen of BIC/FTC/TAF has been well tolerated with low rates of discontinuations due to adverse events, a high barrier to resistance and few drug interactions.” said Joel Gallant, MD, MPH, Medical Director of Specialty Services at Southwest CARE Center in Santa Fe, NM and lead author of Study 1489.
In Study 1490, treatment-naive adults with HIV (n=645) were randomized to receive BIC/FTC/TAF or DTG+FTC/TAF. At Week 48, the primary endpoint of HIV-1 RNA levels <50 copies/mL was achieved by 89.4% of the BIC/FTC/TAF group vs 92.9% of the DTG+FTC/TAF arm (difference –3.5%, 95% CI: –7.9% to 1.0%; P =.12). Discontinuations due to side effects were low in both treatment arms (BIC/FTC/TAF: 1.6% vs DTG+FTC/TAF: <1.0%) with no patients in either group developing resistance to any of the study drugs.
“These data reinforce the safety and efficacy profile consistently seen in other trials evaluating regimens based on the FTC/TAF combination,” said Paul Sax, MD, Clinical Director of the Division of Infectious Diseases at Brigham and Women's Hospital, Boston, Professor of Medicine at Harvard Medical School and lead author of Study 1490. “These results suggest that the combination of bictegravir with FTC/TAF has the potential to be appropriate for a broad range of HIV patients, including those with mild to moderate renal impairment.”
In addition to these studies, bictegravir in combination with FTC/TAF is also being evaluated in 2 ongoing studies involving virologically suppressed adult patients.
- Gilead announces phase 3 results for investigational fixed-dose combination of bictegravir, emtricitabine and tenofovir alafenamide for treatment of HIV [press release]. Foster City, California: Gilead. Published online July 24, 2017. Accessed July 31, 2017.
- Gallant J, Lazzarin A, Mills A, et al. A phase 3 randomized controlled clinical trial of bictegravir in a fixed dose combination, B/F/TAF, vs ABC/DTG/3TC in treatment-naïve adults at week 48. Presented at: IAS 2017; June 23-26, 2017; Paris, France; Oral Abstract MOAB0105LB.