Sixth International Congress on Drug Therapy in HIV Infection
17-21 November 2002, Glasgow, Scotland

Highly active antiretroviral therapy (HAART) in some injection drug users (IDUs) may be challenging for a number of reasons, some of which are:

• risks of interactions between HIV medicine and methadone, resulting in reduced methadone levels and distress from symptoms of withdrawal
• unknown interactions between HIV medicine and street drugs
• toxicity of anti-HIV drugs, particularly in people with pre-existing liver damage from drug use and hepatitis C virus infection
• difficulties in adhering to treatment regimens, particularly among people with chaotic lives

Doctors in Vancouver, British Columbia, have been dispensing HAART and methadone using directly observed therapy (DOT) with selected people with HIV/AIDS (PHAs). These PHAs are also given counselling and referred to social services for additional help in their recovery from drug addiction. In one study, the doctors assessed the effectiveness of HAART in PHAs who had previously received HAART outside their program.

Study Details

Researchers enrolled 60 PHAs (30 females, 30 males), who were divided into the following two groups:

• 19 subjects who had never previously received HAART (treatment-naïve)
• 41 subjects who had previously received HAART (treatment-experienced)

Among treatment-naïve subjects, the majority were given regimens containing the non-nuke nevirapine (Viramune) with two other drugs. Among the treatment-experienced, the majority used regimens containing either the non- nukes nevirapine or efavirenz (Sustiva) along with two other drugs.

Results

Overall, both treatment-naïve and -experienced subjects were equally able to achieve similar decreases in levels of HIV. However, as in many other studies of PHAs, treatment-naïve subjects had greater increases in CD4+ counts compared to experienced subjects. Although not common, a degree of liver toxicity occurred in some subjects. This was manageable and did not interfere with therapy. Their results show that it is possible for some HIV positive IDUs to benefit from directly observed therapy with methadone and HAART.

The research team is currently comparing the benefit of different classes of anti-HIV drugs in HIV positive IDUs.

Reference

1. Conway B, Jutha S, Jones M, et al. Efficacy of directly observed antiretroviral therapy in naïve and non- naïve intravenous drug users (IDUs) receiving methadone replacement therapy. Sixth International Congress on Drug Therapy in HIV Infection, 17-21 November 2002, Glasgow. Poster 94.