Tenth of HIV Cases in a Study in Europe Are Resistant to Drugs
New
York Times
Donald G. McNeil Jr.
July 16, 2003
The biggest study, so far, of resistance to AIDS drugs, being released today at the International AIDS Society Conference on HIV Pathogenesis and Treatment in Paris, finds that about 10 percent of newly infected patients in Europe are infected with drug-resistant strains. Dr. Charles Boucher, virology professor at Utrecht University and lead researcher of the study, called the level of resistance to some AIDS drugs "surprisingly high."
The study, nicknamed CATCH ("Combined analysis of resistance transmission over time of chronically and acute infected HIV patients in Europe"), tested 1,633 patients from 17 European countries who had just been diagnosed with HIV and who had not yet been treated for it. About 9.6 percent of the patients were resistant to at least one of the three types of antiretroviral drugs that suppress the virus. Resistance to nucleoside reverse-transcriptase inhibitors was found in 6.9 percent of those studied; resistance to non-nucleoside reverse-transcriptase inhibitors in 2.6 percent; and resistance to protease inhibitors in 2.2 percent.
Drug-resistant strains appear because the virus mutates rapidly and thrive when patients take their drugs carelessly. For patients to be newly infected with resistant strains, they must have been infected by people with HIV who had gone back to high-risk behavior despite having caught a disease that is usually fatal.
Another result of the CATCH study showed resistance was much higher, at 11.3 percent, among Europeans who had subtype B of the virus, compared to those with non-B subtypes, in whom resistance was 3.3 percent. Subtype B infects 98 percent of American patients and about 60 percent of European patients.
Other scientists suggested that an "order of battle" approach to prescribing AIDS drugs, like that used for TB medicines, should be adopted in place of the current free-for-all. One researcher said public health authorities could tell doctors which drug combinations to prescribe first, second and third as resistance was encountered. Some doctors said the study suggested that all new AIDS patients should be tested to determine the drug resistance of the strains infecting them.