October 17, 2011
HPTN 058, a Phase III clinical trial evaluating whether medication combined with drug and HIV risk-reduction counseling can prevent HIV infection and death among opiate-dependent injection drug users, will cease new enrollment and begin a phased close out. The actions are being taken after an independent data and safety monitoring board (DSMB) recently concluded that based on available study data, the trial will be unable to achieve its primary objectives. The DSMB, therefore, recommended that the study end. As the study's sponsor, the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, agreed with the DSMB's recommendation.
Injection drug use has long been recognized as a major risk factor for HIV infection. Past research has shown that participation in substance abuse treatment helps reduce HIV risk behaviors and lower HIV prevalence among injection drug users. HPTN 058 was examining the effectiveness of a medication containing buprenorphrine and naloxone, an approved treatment for opiate dependence, in combination with a behavioral intervention as an approach for reducing HIV acquisition among those who inject illicit opiates, such as heroin.
Launched in May 2007, HPTN 058 was to enroll 1,500 opiate-dependent, HIV-uninfected adults ages 18 years and older at four sites in China and Thailand. Currently, 1,250 participants are enrolled in the study. Half of the participants were randomly assigned to receive long-term treatment: the buprenorphrine/naloxone combination pill taken daily under the tongue for up to 21 days, until dose stabilization was achieved, and then three times weekly for 52 weeks. The other participants were randomly assigned to receive short-term treatment: the same dual-drug therapy taken daily for approximately three weeks. As part of their treatment, participants in both groups received weekly individual drug- and HIV risk-reduction counseling for 12 weeks, followed thereafter by counseling sessions every four weeks for up to one year.
The study was primarily designed to test whether long-term medication treatment plus drug and HIV risk-reduction counseling worked better than short-term treatment and counseling in reducing the cumulative incidence of HIV infection and deaths among the study participants when evaluated 104 weeks after enrollment. Based on the DSMB's scheduled interim review of the study data, however, the numbers of HIV infections and deaths among study participants were lower than expected and, therefore, the DSMB determined that the study would be unable to demonstrate a difference between the two treatment groups. However, the DSMB noted that the clinical trial will be able to achieve important secondary objectives, including determining whether long-term treatment is better than short-term treatment in reducing the frequency of HIV risk-taking behaviors as measured by urine tests to detect opiate use and self-reports of injected drugs and needle sharing; the number of sexual partners; and the number of unprotected sexual acts. The study also should shed light on whether the long-term treatment group had fewer overall arrests and higher rates of employment as well as fewer hepatitis B and C infections.
Participants are being notified of the decision to close the study. Because no safety concerns were identified by the DSMB, participants will gradually be moved off the study. Individuals who acquired HIV during the study were referred to local community medical services for HIV treatment and care according to national guidelines in China and Thailand. In both countries, antiretroviral treatment is readily accessible and can be made available free or at a reduced cost to HIV-infected individuals. Participants also will receive referrals to local drug treatment resources.
The study is being conducted by the HIV Prevention Trials Network (HPTN), which was established by NIAID in 2006 and is funded jointly by NIAID, the National Institute on Drug Abuse (NIDA), and the National Institute of Mental Health, all part of the NIH. In addition to NIAID, NIDA provided support for HPTN 058.
For more information, visit the HPTN 058 study page.