Once daily pill yields higher ART adherence

Study looked at marginalized populations

Even HIV-infected individuals who have the greatest challenges in adhering to their antiretroviral (ART) can achieve high adherence on a regimen of one pill taken daily, research shows.

"When we looked at one pill taken once a day, adherence was just short of 90%," says David Bangsberg, MD, MPH, director of the Massachusetts General Hospital Center for Global Health and associate professor at Harvard Medical School in Cambridge, MA. Bangsberg was a lead author on the study, which was presented at the 2010 Conference on Retroviruses and Opportunistic Infections (CROI).1

The one pill, once-daily regimen consisted of a combination of efavirenz, emcitrabine, and tenofovir.1

The study looked at individuals recruited from single room occupancy (SRO) hotels, free meal food programs, and homeless shelters. They were within six months of treatment initiation, and adherence was determined for six months using unannounced pill counts at their usual places of residence.1

"This population had all the risk factors for poor adherence," he says. "Indeed, this is an exceptionally high level of adherence in any population."

A near 90% adherence rate is high by ART historical perspective, particularly for a population that is homeless and has drug use and depression issues, Bangsberg notes.

The high level of adherence on ART was associated with good rates of viral suppression, which would imply this one-pill, once-daily treatment would be a successful treatment strategy for a homeless population, he adds.

"Therapy in 1996 was quite complex with 20 pills a day, and it has become much simpler and more potent now with the availability of once-daily, one pill treatment," he explains. "When we looked at adherence in the population receiving more complicated therapy we historically have seen adherence in the high 60s, low 70s."

HIV-infected individuals in the cohort receiving more complicated therapy had an adherence rate of about 70%, Bangsberg says.

Researchers recruited HIV patients who mostly were receiving routine care at publicly-funded HIV clinics in the Tenderloin mission areas of San Francisco, Bangsberg says.

Most of the study participants picked up their medications at pharmacies.

"With their permission and informed consent, we would go to their usual place of residence, sometimes an SRO or homeless shelter, sometimes on the street, and on a random day we would count their pills to see how many they had in their possession," Bangsberg says. "We did that every month for six months."

The study's results clearly demonstrate that excellent adherence results can be achieved with a single-pill, once-daily ART regimen even among a challenging population that has many risk factors for poor adherence, Bangsberg says.


  1. Bangsberg D, Ragland K, Monk A, et al. A one-pill, once-daily fixed-dose combination of efavirenz, emcitrabine, and tenofovir disoproxil fumarate regimen is associated with higher unannounced pill count adherence than non-one-pill, once-daily regimens. Abstract presented at the 17th Conference on Retroviruses and Opportunistic Infections (CROI), held Feb. 16-19, 2010, in San Francisco, CA. Abstract:1000.