HIV Strains Showing Increased Resistance to Drugs
As many as one in every seven Americans newly infected with HIV has a strain that is resistant to at least one of the antiretroviral drugs currently used to treat the infection, a "sharp increase" from only a few years ago, according to recent studies on drug-resistant viral strains. At the 8th Conference on Retroviruses and Opportunistic Infections in Chicago, Dr. Susan Little of the University of California-San Diego released results from a nine-city study of 394 patients -- diagnosed an average three months after infection -- that revealed 14% of the patients showed a "tenfold reduction in susceptibility to at least one class of anti-HIV drugs" between 1999 and early 2000, compared to only 3.5% between 1995 and 1998. Study results also showed that in the past two years, the percentage of those resistant to two or more drugs grew from 0.4% to 5.8%. A separate Harvard and Boston University study reported that 18% of 88 newly diagnosed patients in Boston were resistant to at least one class of drugs and 12% were resistant to at least two. Studies in France and Switzerland showed similar results. The "more alarming findings" show that for patients who were treated with antiretroviral drug combinations of three or more drugs, resistance to one drug "limit[ed] the utility of all classes of drugs." Little explained that HIV patients with a resistant strain "are less likely to suppress virus replication with therapy, take longer to suppress the virus and have a shorter time to therapy failure." As a result, she recommended that all individuals newly diagnosed with HIV be tested for the presence of resistant strains and that medication regimens be "tailored" to eliminate drugs to which the strains are resistant (Maugh, Los Angeles Times, 2/7). The emergence of drug-resistant strains will continue to be a problem unless new classes of drugs are introduced, but Dr. David Ho of the Aaron Diamond AIDS Research Center in New York said that although several new drugs are on their way, they "may not arrive in time to save people who began therapy in 1996" (Sternberg, USA Today, 2/7).This is part of the KHN Morning Briefing, a summary of health policy coverage from major news organizations. Sign up for an email subscription.