A study by the National Institute of Allergy and Infectious Diseases shows that HIV-positive patients who cycle their antiretroviral drug therapy at weekly intervals do little or no damage to their health, reports The Washington Post. The study is far from definitive, researchers said when presenting their results at the 8th Annual Conference on Retroviruses and Opportunistic Infections, but if the findings are verified by further studies, patients may be able to cut in half the amount of time they have to undergo the sometimes toxic drug treatment. In the study, patients received therapy for seven days, then went off the drugs for seven days, during which time the virus remained fully suppressed. Several of the study patients continued cycling their therapy for 10 months and showed no evidence of damage to their immune systems or the development of resistant strains of the virus. Researchers do not yet know if long-term cycling will lead to drug resistance or reduce the side effects of the antiretroviral medications. Anthony Fauci, head of NIAID, said more study is needed and cautioned patients against cycling their medications without the advice of their doctor.