HIV Digest	HIV Digest Archive

The National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH), today announced that enrollment into a large international HIV/AIDS trial comparing continuous antiretroviral therapy with episodic drug treatment guided by levels of CD4+ cells has been stopped. Enrollment was stopped because those patients receiving episodic therapy had twice the risk of disease progression (the development of clinical AIDS or death), the major outcome of the study.

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The trial, known as Strategies for Management of Anti-Retroviral Therapy, or SMART, was designed to determine which of two different HIV-treatment strategies would result in greater overall clinical benefit. HIV-positive volunteers were assigned at random to either a viral suppression strategy, in which antiretroviral therapy (ART) was taken on an ongoing basis to suppress HIV viral load; or a drug conservation strategy, in which ART was started only when the levels of key immune cells, called CD4+ cells, dropped below 250 cells per cubic millimeter. Volunteers in the drug conservation group were taken off ART­ with the aims of reducing drug side effects and preserving treatment options­ whenever their CD4+ cells were above 350 cells/mm3. (For more details see www.smart-trial.org).

The trial involved an international collaboration of 318 clinical sites in 33 countries. It began enrollment in January 2002 and had successfully recruited more than 90 percent of its target of 6,000 participants: as of January 11, 2006, when enrollment was stopped, 5,472 volunteers had joined the study.

At the time of the safety review, the average follow-up was approximately 15 months. The analysis revealed that participants on CD4+ cell-guided episodic treatment faced more than twice the risk of disease progression relative to participants on continuous ART. Furthermore, there was an increase in major complications such as cardiovascular, kidney, and liver diseases in the participants on the drug conservation arm. These complications have been associated with ART, and it was hoped that they would be seen less frequently in those patients receiving less drug.

Editor's Note: from the National Institute of Allergy and Infectious Diseases