DAAT may work where DOT model fell short

Good results for drugs issued by methadone clinics

While there are some similarities between HIV and tuberculosis (TB) treatments, it’s the differences in treatment regimens, duration, and end results that have made HIV clinicians and others somewhat hesitant to use the directly observed treatment (DOT) strategy, which has been so successful in treating TB, with HIV patients.

"For a number of years, people have been wondering whether DOT could help at least a subset of people treated for HIV," says Gregory M. Lucas, MD, assistant professor at the Johns Hopkins University School of Medicine in Baltimore.

However, the drawbacks to modeling HIV treatment after DOT have been that unlike TB medication, HIV medication always is prescribed daily and that HIV is incurable so medications must continue for the patient’s lifetime, rather than for the six months that a typical TB patient might receive treatment, he says.

Johns Hopkins researchers have found a possible solution to these barriers in a treatment modeled after DOT, which they have named directly administered antiretroviral therapy (DAAT), which has demonstrated good outcomes when used with an injection drug using population on maintenance methadone treatment.

"Obviously, in a methadone-maintenance clinic, you have 100% of people who have heroin addiction and a very high HIV prevalence in that population," Lucas says. "Also, a lot of studies have shown that drug users aren’t as successful with HIV treatment."

So this is a population that clearly could benefit from a program that works at improving HIV medication adherence, and the population can be served in a setting where patients arrive each day to receive their methadone.

"You could do DAAT indefinitely, and it doesn’t require nurses or other community workers to go out into the community and find people to give the medications to," he explains.

"About two years ago, we started a pilot study and, to date, we have enrolled about 35 people who are receiving methadone and who have HIV and are eligible for antiretroviral therapy," Lucas says.

"Somewhere between 70% and 80% of the people enrolled in the program have achieved an undetectable viral load of less than 400 copies," he explains. The pilot study is not randomized, but investigators also are following a large cohort study of 2,500 active HIV patients and so there is a matched control group, he adds.

"Our DAAT group really is doing a lot better than what is occurring with the standard care," Lucas says.

The DAAT project works this way:

  • HIV clinicians prescribe antiretroviral regimens to patients who are receiving methadone therapy.
  • Trained staff give patients their antiretroviral medications at the methadone clinic and watch as the patients take the pills.
  • Staff also give patients a packet with the pills they’ll need to take later that day.

"It’s a modified DOT protocol, which really is done for feasibility purposes," he points out. "It’s hard to track down people and observe them taking medications twice a day, and it’s not realistically done in any outpatient setting."

Soon there may be more once-per-day antiretroviral treatment options available, which will make DAAT even easier to monitor, Lucas notes.

"The staff we have who are involved with this are enthusiastic and bond with the patients," he says. "They are involved with their lives and help them get whatever help they need, and there is more to it then just seeing some medications going into someone’s mouth."

One of the advantages to this approach is that there are federal funds available for HIV programs that target disadvantaged patients and if studies continue to show that DAAT at methadone treatment clinics work then more of these programs would become eligible for federal grants, Lucas says.

Many of the people who use methadone treatment clinics are racial minorities, women, and have low incomes, all of which contribute to their having a difficult time accessing HIV care through the usual routes, Lucas adds. "It’s a hard-to-reach population."

Plus, Ryan White programs already have funded a number of slots for methadone treatment to be provided for uninsured HIV-infected women, Lucas says.

The next step is to study DAAT in a randomized, controlled trial where people either receive DAAT or just take the medications on their own, Lucas says, adding that investigators also are exploring the options of working with larger methadone treatment clinics in the area.

Reference

1. Lucas GM, Weidle PJ, Hader S, et al. Directly administered antiretroviral therapy improves rates of viral suppression compared to standard care or an intensive adherence intervention. Presented at the 40th Annual Meeting of the Infectious Diseases Society of America. Chicago; October 2002. Poster 489.