Retention in opioid replacement programmes improves chances of HIV treatment working for drug users

Michael Carter
Published: 29 October 2009

HIV-positive injecting drug users who are retained in opioid substitution therapy programmes have an increased chance of maintaining an undetectable viral load when taking HIV treatment, French investigators report in the November 1st edition of Clinical Infectious Diseases.

“Our study presents important evidence of the positive impact of retentions on OST [opioid substitution treatment] on HIV outcomes,” write the investigators. They also comment, “for HIV-infected injecting drug users who receive both HAART [highly active antiretroviral therapy] and OST, the longer the duration in OST, the higher the likelihood of virological success.”

Retention in opioid substitution treatment was associated with an increased chance of having an undetectable viral load even when adherence was taken into consideration.

Injecting drug users remain one of the groups most affected by HIV. Individuals from this population are regarded as hard to treat, and they have not benefited from HIV treatment as much as other transmission groups.

This is often because doctors are concerned that drug users will have difficulty taking their HIV treatment correctly. Physicians can therefore be reluctant to provide antiretroviral therapy until individuals have successfully addressed their drug-using behaviours.

With good adherence, injecting drug users benefit from HIV treatment just as much as other patients. Treatment with opioid substitutes such as methadone and buprenorphine can help stabilise injecting drug users, and both drugs are on the World Health Organization’s (WHO) list of essential medicines.

Investigators from the French MANIF 2000 cohort study wished to see if retention into treatment programmes that provided these drugs as opioid substitution improved virologic outcomes in HIV-positive injecting drug users taking antiretroviral treatment.

Their study population included 113 patients who were followed up every six months for up to five years. At each study visit, details of opioid substitution therapy were obtained, viral load was monitored, and information on adherence was gathered.

On entry to the study, all the patients had been taking HIV treatment for at least six months. The investigators defined virological success as a viral load below 50 copies/ml (an undetectable viral load). Long-term virological response was considered to be an undetectable viral load for at least six months.

Only 42% of the injecting drug users reported taking all their HIV treatment, and only 29% had an undetectable viral load at baseline.

Methadone was provided to 25% of individuals and buprenorphine to 29%. The others individuals received no opiate replacement.

Most (70%) patients achieved a viral load at least once during the study.

Statistical analysis that took into account possible confounding factors showed, unsurprisingly, that patients with less-than-perfect adherence as well as those who interrupted their antiretroviral therapy were less likely to achieve an undetectable viral load.

However, the investigators also found that the longer a patient remained in the opioid substitution programme, the greater their chances of achieving long-term HIV suppression, even if adherence of less than 100% was taken into consideration. Every six months of inclusion in a treatment programme increased the chance of long-term virological suppression by 20% (OR, 1.20; 95% CI, 1.08 to 1.32).

Results of the study also showed that the greater the total amount of time for which a patient was enrolled in a methadone substitution programme, the greater their chances of having a virologic response to antiretroviral therapy (OR, 1.17 per six month increase; 95% CI, 1.06 to 12.9).

Better virological outcomes were seen in patients taking methadone compared to buprenorphine.

“Our results underline the importance of providing HIV-infected drug users with an appropriate model of comprehensive care, aimed at optimizing retention in opioid substitution therapy and HAART,” conclude the investigators.


Roux P et al. Retention in opiod substitution treatment: a major predictor of long-term virological success of HIV-infected injection drug users receiving antiretroviral therapy. Clin Infect Dis 49: 1433-40, 2009.

Community Consensus Statement on Access to HIV Treatment and its Use for Prevention

Together, we can make it happen

We can end HIV soon if people have equal access to HIV drugs as treatment and as PrEP, and have free choice over whether to take them.

Launched today, the Community Consensus Statement is a basic set of principles aimed at making sure that happens.

The Community Consensus Statement is a joint initiative of AVAC, EATG, MSMGF, GNP+, HIV i-Base, the International HIV/AIDS Alliance, ITPC and NAM/aidsmap

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