A once-weekly oral HIV pill worked just as well as a standard daily three-drug regimen in a large international clinical trial, according to results published July 29 in The New England Journal of Medicine.
The trial, called ISLEND-1, enrolled 607 adults at 106 sites across 12 countries. Researchers randomly assigned 304 participants to switch to the weekly pill, which combines two antiretroviral drugs, islatravir and lenacapavir. The other 303 participants continued taking Biktarvy, a three-drug combination taken once daily that is considered a standard of care. After 48 weeks, none of the participants on the weekly pill had a viral load at or above 50 copies per milliliter, the threshold used to measure viral suppression. One participant in the daily Biktarvy group crossed that threshold.
Healthline reported on the findings, which were described as a noninferior result, meaning the weekly pill did not perform meaningfully worse than the established daily therapy.
Charles Flexner, MD, a professor of Medicine, Physiology, Pharmacology and Therapeutics, and International Health at the Johns Hopkins University School of Medicine, said the trial "demonstrates very convincingly that [a pill] containing two anti-HIV drugs given once a week is just as effective at preventing the virus from replicating or reproducing as one of the standard, gold-standard, three-drug combination pills taken once a day." Flexner was not involved in the research but has served as a paid consultant for Gilead and Merck, the companies developing the weekly pill.
The trial was funded by Gilead Sciences and Merck Sharp and Dohme. All participants had maintained viral suppression for at least six months before the trial began, had no history of virologic treatment failure, and had not previously used either islatravir or lenacapavir. Participants also had no active hepatitis B infection.
Study participants had a median age of 49. Fifteen percent were 65 or older. About 21% were female, 31% were Black, 26% were Hispanic, and 11% were Asian.
Researchers noted that the weekly pill could help address what they described as pill fatigue, the burden some patients experience from taking medication every single day. Because all participants in the trial already had well-controlled HIV and high adherence to their existing medication, researchers acknowledged that the results may not apply to all people living with HIV.
The drug combination is not yet approved. The trial represents phase 3 testing, which is typically required before a treatment can move through the regulatory approval process.
