Glaxo, Gilead AIDS Drugs Cut Transmission to Partners by 96%, Study Shows

Millions of HIV infections could be averted by treating patients earlier than current guidelines recommend, after a study showed giving pills to patients as soon as they’re diagnosed can prevent them infecting others.

In a trial among 1,763 couples where only one partner was infected, those who started treatment immediately were 96 percent less likely to transmit the AIDS-causing virus to their uninfected partner than those who started therapy later. The study, which was due to end in 2015, was terminated early because the effect was so clear, U.S. National Institute of Allergy and Infectious Diseases said in a statement yesterday.

The findings are the first to prove that treating a person reduces their risk of infecting others, and may change the pace of care for people with the world’s deadliest virus. The World Health Organization currently recommends patients with healthy immune systems not get HIV drugs, which can have serious side effects, until their infection-fighting cells fall below a certain level.

“This new finding convincingly demonstrates that treating the infected individual -- and doing so sooner rather than later -- can have a major impact on reducing HIV transmission,” Anthony Fauci, NIAID’s director, said in the statement.

The researchers found 28 new HIV cases in which an infected person transmitted the virus to their partner, which they confirmed by genetic testing. Of those, only one was among the 886 couples where treatment began immediately with a mix of drugs from companies including Gilead Sciences Inc. (GILD) and Bristol- Myers Squibb Co. The 27 other infections were among 877 couples where treatment was delayed.

2.6 Million Infected

About 2.6 million people became infected with HIV in 2009, 21 percent less than in 1997 when annual infections peaked at about 3.2 million, the United Nations’ AIDS program, UNAIDS, said in a report last year. Still, only 36 percent of the 15 million people who need treatment in developing countries in Africa and Asia are getting it, the report said.

The trial, dubbed HPTN 052, bolsters the idea of treating people as a means of prevention and may reduce infection rates if the findings are properly implemented, said Mitchell Warren, executive director of the AIDS Vaccine Advocacy Coalition.

“These data must serve as a clarion call to funders, policy makers, civil society and implementers,” he said in a statement. “If deployed effectively, efficiently and ethically, early initiation of treatment will be fundamental to turning the tide of the epidemic.”

Trial Participants

The trial was funded by the U.S. National Institutes of Health and conducted in South Africa, Kenya, Thailand, India, Brazil, Botswana, Malawi and Zimbabwe. The drugs were provided by Foster City, California-based Gilead, New York-based Bristol- Myers, Abbott Laboratories (ABT) of Abbott Park, Illinois, German drugmaker Boehringer Ingelheim GmbH, Merck & Co. of Whitehouse Station, New Jersey and Viiv Healthcare, which is a joint venture of New York-based Pfizer Inc. (PFE) and London-based GlaxoSmithKline Plc. (GSK)

The findings don’t apply to men who have sex with men since 97 percent of the couples studied were heterosexual, the researchers said. Only one couple came from the United States, where investigators had trouble finding participants.

Drugs to treat HIV can cost $12,000 or more a year, and cause side effects including nausea and kidney damage. Studies are under way to identify the best time to start the drugs that must be taken daily for life. There is no hard and fast rule on when to begin treatment for patients who still have a strong immune system without signs of AIDS.

Researchers will continue to monitor volunteers in the study to see if the benefit lasts. While some nations including the U.S. have recommended starting treatment earlier, the study’s finding suggests more patients should get the pills upon diagnosis, doctors said.

Tuberculosis Rates

Tuberculosis developed in 17 people getting delayed treatment and three who received immediate drug therapy in the study. There was no significant difference in the number of deaths seen in the trial.

The study proves early treatment improves patient’s health and dramatically reduces new HIV infections in their partners, said Robert Grant, associate professor at the Gladstone Institute of Virology and Immunology at the University of California, San Francisco.

“Never before have so many effective HIV prevention tools and strategies been available,” he said.

Grant’s earlier study, called iPrEx, showed giving Gilead’s Truvada to gay men who didn’t have HIV reduced their infection rates by 44 percent.

Lower Viral Levels

In the study reported yesterday, patients were treated with a triple combination of drugs chosen from among 11 options, with the goal of reducing the amount of virus in their blood to undetectable levels. Researchers hypothesized that HIV patients with lower viral levels would be less likely to infect their partners, and the earlier treatment starts, the greater the benefit.

Half started taking the drugs immediately after joining the trial, and the other half waited until their CD4 cells -- the immune system cells attacked by the virus -- fell below 250 per cubic millimeter of blood.

The study cost about $73 million and was carried out by the HIV Prevention Trials Network. All the participants received condoms and counseling on how best to prevent the spread of HIV.

To contact the reporters on this story: Michelle Fay Cortez in Minneapolis at mcortez@bloomberg.net; Simeon Bennett in Singapore at sbennett9@bloomberg.net

To contact the editor responsible for this story: Reg Gale at rgale5@bloomberg.net

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