Get the latest updates as we post them — right on your browser

. Last Updated: 07/27/2016

Drug-Resistant AIDS Strains Spread in Europe

NEW YORK -- The biggest study so far of resistance to AIDS drugs, released Wednesday at an international AIDS conference in Paris, finds that about 10 percent of all newly infected patients in Europe are infected with drug-resistant strains.

The researcher who led the study called the level of resistance to some anti-AIDS drugs "surprisingly high." Other scientists at the conference agreed that the findings have worldwide public health implications and make the hunt for new classes of AIDS drugs even more critical.

They said the figure suggests that many average AIDS patients in treatment resume engaging in high-risk sex or needle-sharing. It also suggests that an "order of battle" approach to prescribing AIDS drugs, like that used for tuberculosis medicines, should be adopted in place of the current free-for-all.

For example, one researcher said, a drug like nevirapine, which can prevent mother-child transmission with just one dose, might be restricted to that use only, so resistance to it cannot grow as it would if thousands of patients were put on it for life. Also, public health authorities could tell doctors which drug combinations to prescribe first, second and third as resistance is encountered.

Smaller tests to measure resistance have been done in San Francisco, in a group of several other U.S. cities, and in Switzerland. While some of those found higher levels of resistance -- of 225 patients in San Francisco, 27 percent were drug-resistant -- the new study is thought to be the first to give a reliable measure of the phenomenon across a broader population, said Charles Boucher, the virology professor at the University of Utrecht who led the study.

"You're not talking about high-risk inner city San Francisco," he said. "This is across Europe."

Some doctors said the study suggested that all new AIDS patients should be tested to determine the drug-resistance of the strains infecting them.

Other experts said that the findings underscored the need for better guidelines on the medicines' use as the treatment effort gears up. "It means we have to be smart about how we use the drugs to avoid as much resistance as we can," said Dr. Scott Hammer, chief of infectious disease at Columbia-Presbyterian Medical Center in New York, who attended the International AIDS Society conference in Paris this week.

The study tested 1,633 patients from 17 European countries who had just been diagnosed with the virus that causes AIDS and who had not yet been treated for it. The study is nicknamed the Catch study for "combined analysis of resistance transmission over time of chronically and acute infected HIV patients in Europe."

About 9.6 percent of the patients were resistant to at least one of the three types of anti-retroviral drugs that suppress the virus that causes AIDS.

There are 17 such drugs, but they all fall into three classes: nucleoside reverse-transcriptase inhibitors, non-nucleoside reverse-transcriptase inhibitors, and protease inhibitors. Normally, a patient takes a "triple therapy cocktail" of all three to attack the virus three ways.

Drug-resistant strains appear because the virus mutates rapidly and they 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 went back to high-risk behavior despite having caught a disease that is usually fatal.

The growth of resistance "is a fact of life," said Joep Lange, a professor of internal medicine at the University of Amsterdam and president of the International AIDS Society. "It happens with antibiotics; it happens with TB. If you use drugs, you'll eventually see resistant strains."

Dr. Roy Gulick, a professor at Cornell University's Weill Medical College, said the study showed that prevention efforts in wealthy countries should focus not just on uninfected young people but on infected ones, "to tell them, 'You have the infection but you shouldn't spread it to other people,'" he said.

A worldwide scheme to fight AIDS received fine words but little new cash to bridge a looming funding gap as ministers from 14 countries met in Paris on Wednesday, Reuters reported.

The Global Fund to Fight AIDS, Tuberculosis and Malaria, which has committed $1.5 billion to programs in 92 countries in the last 18 months, lacks money for schemes waiting to be funded at its next meeting in October.

Hopes of major new pledges from Europe after U.S. President George W. Bush promised $15 billion to fight AIDS over five years were dashed this week when the European Commission made clear it would not be putting new cash on the table.