Patients with HIV experienced a significantly higher rate of virologic suppression after taking Gilead’s Genvoya (elivitegravir-cobicistat-emtricitabine-tenofovir alafenamide) than the company’s Stribild (elvitegravir-cobicistat-emtricitabine-tenofovir disoproxil fumarate), based on the percentage of patients with HIV-1 RNA levels less than 50 copies/mL.
Two Phase III studies examined the treatment of HIV-1 infection in treatment-naive adults. Through week 144, patients receiving Genvoya also showed favorable renal and bone laboratory parameters compared with those treated with Stribild. The data were presented in a poster session (poster 0393) at the 2017 Conference on Retroviruses and Opportunistic Infections earlier this year.
Genvoya is indicated as a complete regimen for the treatment of HIV-1 infection in adults and pediatric patients 12 years of age and older who have no antiretroviral treatment (ART) history or to replace the current ART in those who are virologically suppressed (HIV-1 RNA Genvoya carries a boxed warning in its product label regarding risks for lactic acidosis/severe hepatomegaly with steatosis, and post-treatment acute exacerbation of hepatitis B.
“As people grow older with HIV, physicians are increasingly looking for highly effective medications that may help address the evolving needs of their patients who face a lifetime of antiretroviral therapy,” said Dr Jose Arribas, an associate professor of medicine, Hospital La Paz, in Madrid, and the lead study investigator. “These study results further demonstrate that Genvoya provides durable viral suppression and has a demonstrated safety profile for long-term use by a range of appropriate HIV patients.”
In the combined analysis of studies 104 and 111, a total of 1,733 treatment-naive adults with HIV were randomly assigned to receive Genvoya or Stribild. At 144 weeks, 84.2% of patients (729/866) taking Genvoya and 80% of patients (694/867) (P=0.021) taking Stribild achieved HIV-1 RNA levels of less than 50 copies/mL. Additionally, at the same time point, 81.1% of patients (702/866) taking Genvoya and 75.8% of patients (657/867) (P=0.006) taking Stribild achieved HIV-1 RNA levels of less than 20 copies/mL, a secondary end point.
At week 144, virologic failure was similar between groups (Genvoya, 4.6%; Stribild, 3.9%); the difference in overall results was attributable to fewer discontinuations on Genvoya caused by adverse events (AEs) or other reasons unrelated to efficacy (Genvoya, 11.2%; Stribild, 16%). There were statistically significantly fewer AEs leading to discontinuation in the Genvoya arm (1.3%) than the Stribild arm (3.3%) (P=0.01). The most common drug-related AEs in both groups were nausea, diarrhea and headache.
A separate analysis investigated the effect of the two regimens on laboratory parameters of kidney, bone and plasma lipid changes. To examine kidney function, specific protein markers of glomerular and tubular function were measured, all of which favored Genvoya. These values included a statistically significant difference in the median change in estimated glomerular filtration rate (eGFR) from baseline to week 144 (Genvoya, –1.6 mL per minute; Stribild, –7.7 mL per minute; P<0.001). There were no cases of renal tubulopathy in the Genvoya arm and four cases in the Stribild arm. No recipients of Genvoya had renal-related discontinuations compared with 12 recipients of Stribild (P<0.001).
The analysis also found that reductions in bone mineral density (BMD) were significantly less in the Genvoya group than the Stribild group for both lumbar spine and total hip (spine: Genvoya, –0.92%; Stribild, –2.95%; P<0.001; hip: Genvoya, –0.75%; Stribild, –3.36%; P<0.001). The long-term clinical significance of changes in eGFR and BMD is not known. Finally, patients on Genvoya had significantly higher increases in total cholesterol and low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol from baseline to week 144 than patients on Stribild. There was no significant difference in the ratio of total cholesterol to HDL cholesterol at 144 weeks, nor any difference in the rate of initiation of lipid-modifying agents.
Studies 104 and 111, originally planned for 96 weeks and extended to 144 weeks, were randomised, double-blind, controlled Phase III trials involving 1,733 treatment-naive adults with HIV. The primary end point was at week 48, when Genvoya was non-inferior to Stribild.