AIDS THERAPY: Combining HAART with IL-2 Boosts Immune System inAdvanced HIV Infection, Study Says

Supplementing highly active antiretroviral therapy (HAART) with interleukin-2 (IL-2), a human protein that stimulates immune cell production, may help individuals with advanced HIV infection rebuild their immune systems faster than with HAART alone, a new study has found. The Associated Press reports that the study, presented yesterday at the 5th International Congress on Drug Therapy in HIV Infection in Glasgow, was performed by University of California-Los Angeles researchers and funded by the National Institute of Allergy and Infectious Diseases. Researchers recruited 161 patients with CD4 cell (T cell) counts as low as 50, indicating advanced progression of the infection, and randomly assigned them to two different groups: 109 patients received "combination therapy," including a daily regimen of HAART and a five-day course of IL-2 every eight weeks, while 55 patients received HAART alone. Researchers found that patients receiving the combination therapy exhibited a "dramatic increase" of new CD4 cells. HAART alone increased CD4 cells by a median of 32%, compared with 137% with the combination therapy. In a second "surprise" finding, researchers found that patients receiving IL-2 experienced "fewer episodes of AIDS-related illnesses," such as Kaposi's sarcoma, lymphoma and pneumonia. Study leader Dr. Ronald Mitsuyasu, director of the UCLA Clinical AIDS Research and Education Center and associate director of clinical services for the UCLA AIDS Institute, cautioned that this finding is "inconclusive" without carrying out a second study specifically designed to investigate this outcome. A third finding determined that "injection of IL-2 beneath the skin -- which patients can self-administer -- offers the same therapeutic benefits as intravenous injection," providing patients with a convenient alternative. IL-2 manufacturer Chiron Corp. is now planning to launch international Phase III trials to test the drug on a larger population, and is recruiting 1,400 patients with advanced HIV infection for the study (Associated Press, 10/25).