Opioid Agonist Therapy Examined for HIV Prevention

In response to the ongoing opioid epidemic, a team of investigators are looking to inhibit the spread of HIV among injection drug users who may share needles.

“There’s an opioid epidemic in our country, and there’s a real public health crisis associated with injecting,” said Cora Bernard, lead author of a prevention programs study published in PLOS Medicine.

For the study, the investigators examined cost-effective alternatives to pre-exposure prophylaxis (PrEP) that could help reduce the risk of HIV. They created a model to determine the number of quality-adjusted life years a person could gain from 4 different HIV prevention methods, and how much they would cost.

“The dynamics of HIV prevention and treatment are complex,” said senior author Margaret Brandeau, PhD. “Our model allows us to evaluate the costs and effects of the interventions, singly and in combination, to determine what programs would be effective and cost-effective in preventing the spread of HIV among persons who inject drugs.”

The prevention programs examined in the study were opioid agonist therapy (OAT), needle-syringe exchange programs, test-and-treat programs, and PrEP. The results of the study showed that OAT was the most cost-effective of the prevention programs simulated in the model. OAT replaces opioids, such as heroin, with a prescription that has similar effects, but under safer conditions. Methadone and buprenorphine maintenance therapy is the most commonly used therapy, according to the study.

Needle-syringe exchange programs were the second most cost-effective options, followed by test-and treat programs. If taken properly, PrEP can successfully reduce the risk of HIV by 92% to 99%, but it is costly. The investigators estimated that PrEP would likely cost more than $600,000 per quality-adjusted life year, compared with less than $50,000 for the other 3 techniques.

The prevention programs were found to be most effective when used in combination. The authors project that OAT and needle-syringe exchanges combined could avert up to 40,000 HIV infections over 20 years among people who inject drugs (PWID). In addition to reducing the risk of HIV, OAT also help individuals stop injecting drugs. If OAT access is expanded, the authors project that it could decrease the size of the PWID population by up to 23% over 20 years for low-coverage expansions and up to 37% for more extensive program expansions.

“We started out thinking about this as an HIV problem, but we realized that the majority of health benefit actually comes from reducing injection drug use and improving quality of life for drug users,” Bernard said. “This is why we found OAT to be the highest-value investment.”

Implementing programs and techniques like OAT could help reduce the effects of the opioid epidemic, the authors noted. “Our study aims to help policymakers and clinicians understand how a variety of interventions can help improve health outcomes and prevent HIV,” concluded co-author Douglas Owens, MD. “We hope our analyses help show how to use limited resources efficiently to prevent the devastating consequences of substance use.”

Reference

• Bernard CL, Owens DK, Goldhaber-Fiebert JD, Brandeau ML. Estimation of the cost-effectiveness of HIV prevention portfolios for people who inject drugs in the United States: A model-based analysis. PLOS Medicine, 2017; 14 (5): e1002312 doi: 10.1371/journal.pmed.1002312