THURSDAY, July 5, 2007 (HealthDay News) -- Two antiretroviral drugs used in combination are successful in controlling drug-resistant HIV/AIDS after six months of treatment, a new phase 3 trial concludes.
The drugs, etravirine and darunavir (brand named Prezista), are both manufactured by Tibotec, a Johnson & Johnson company.
This was the first clinical trial to combine the two new investigational drugs against HIV/AIDS. By week 24 of therapy, patients receiving both drugs achieved better viral suppression than people who were only taking Prezista, according to the study, which is published in a special July 7 HIV-themed issue of The Lancet.
People from 18 nations participated in the trial, including participants enrolled at 30 U.S. sites.
"This study is one of the most significant worldwide HIV/AIDS clinical trials in recent years. It showed that when the two drugs are used in combination, there is a good chance HIV can be very effectively controlled in patients who have advanced, multi-drug resistant HIV," said study co-author Dr. William J. Towner, medical director of Kaiser Permanente Southern California's HIV/AIDS Research Trials, in a prepared statement.
Kaiser Permanente, the second largest provider of HIV care in the United States, enrolled the highest number of participants in the study.
According to Towner, the ongoing study, known as "DUET-2," is the pivotal test of effectiveness for etravirine, which is in a class of drugs called non-nucleoside reverse transcriptase inhibitors.
Results from the clinical phase 3 trial will now be submitted to regulatory authorities, which must grant their approval before the new drug can be made widely available in clinics. Prezista, in another class of drugs, called protease inhibitors, was an experimental drug when the study started but is already approved for use to treat HIV/AIDS.
Italian lead investigator lead investigator Dr. Adriano Lazzarin is expected to present the findings during the July 22-25 International AIDS Society conference in Sydney, Australia.
In another phase 3 trial, also published in the July 7 issue of The Lancet, an international team led by Dr. Jose Valdez Madruga, of the Centro de Referencia e Treinamento DST/AIDS, in Sao Paolo, Brazil, compared the safety and effectiveness of darunavir against another protease inhibitor, lopinavir (Kaletra), in 595 HIV-positive patients who were also taking the protease inhibitor ritonavir (Norvir).
Forty-eight weeks into treatment, 77 percent of patients taking a darunavir-ritonavir combo had significantly lowered HIV viral load, compared to 68 percent of patients taking lopinavir-ritonavir, the study found. Taken together, darunavir-ritonavir also appeared to do a better job at keeping HIV drug resistance mutations at bay, the researchers reported. The two therapies' safety profiles were similar.
Based on the findings, the researchers called the darunavir-ritonavir combination "a treatment option for this [HIV-infected] population."
More than a million Americans are currently living with HIV. The virus has killed more than 524,000 Americans to date.
More information
To learn about HIV/AIDS, visit the U.S. Centers for Disease Control and Prevention.
