News and Features
Two African Studies Show Circumcision to Be a Powerful HIV Prevention Method
HIV/AIDS continues to be very pervasive, particularly in Africa, despite efforts to increase awareness and knowledge of prevention methods. Two studies were published in the February 24, 2007, issue of The Lancet, which indicate that male circumcision can be an effective preventive measure to help reduce HIV transmission. The final results of these studies show that circumcision is even more effective than preliminary reports originally indicated in December 2006.
A study in Kisumu, Kenya involved 2,784 HIV-uninfected male participants, ages 18-24. Half of the men were circumcised at the beginning of the study, and the other half remained uncircumcised with the option of receiving the procedure at the study's end. The aims of the researchers were to determine if circumcision was safe, if receiving the procedure would cause changes in sexual behavior, and if circumcision could offer protection against HIV infection. The results after an average of 24 months of follow-up showed that circumcision was safe, did not cause any significant changes in sexual behavior, and was 60% effective in preventing HIV transmission.
Another study in Rakai, Uganda involved 4,996 HIV-uninfected male participants, ages 15-49. As in the Kenyan study, participants were randomly assigned to either receive circumcision immediately or to have the option of receiving the procedure at the study's end. The results after 24 months in the Ugandan study showed that HIV incidence was lowered by up to 60% in men who received circumcision as opposed to those who did not. Based on these results, the researchers concluded that circumcision can be recommended as a safe and effective prevention tool against HIV infection.
These studies, which included a large numbers of participants, indicate that circumcision may help to significantly reduce the rates of HIV transmission in men. Although this treatment has been shown to be reasonably effective, researchers worry that men who receive circumcision may believe they are fully protected from HIV transmission and engage in riskier sexual behavior. As a result, researchers hope that circumcision will be integrated with other preventive methods in order to slow the spread of HIV.
Member of New Integrase Inhibitor Class of Antiretroviral Drugs Shows Promise
Very promising clinical trial data on a member of a new class of antiretroviral drugs was presented at this week's 14th annual Conference on Retroviruses and Opportunistic Infections (CROI).
Raltegravir (previously known as MK-0518) is a member of the integrase inhibitor class of HIV drugs. Integrase inhibitors fight HIV by blocking the virus from inserting, or integrating, its DNA into the DNA of the host cell, a critical step in the life cycle of the virus.
Data was reported from phase III trials of raltegravir with treatment-experienced patients. After 16 weeks of treatment with 400 mg of raltegravir twice daily in addition to an optimized treatment regimen, 79% of patients had their HIV levels drop to below 400 copies/ml versus 43% of patients receiving placebo and optimized treatment. Even more striking, 61% of patients taking raltegravir alone experienced reduced viral load versus 5% of patients taking placebo alone. CD4 count increased 2-3 times more in patients taking raltegravir than in those receiving placebo. Importantly, there were no significant side effects associated with taking the drug.
The introduction of a new class of anti-HIV drugs provides a broader range of weapons to fight HIV and may even replace currently prescribed drugs that are less effective or have more side effects.