Testosterone replacement drugs, a $1.6 billion market for AbbVie Inc., Eli Lilly and Co. and others, boosted the odds of having a heart attack, stroke or dying by 29 percent in one of the first studies weighing the therapy's cardiovascular risk.
Researchers assessed data from 8,709 men treated in the U.S. Veterans Affairs health system, many with underlying illnesses, including prior heart attacks and diabetes. While the study didn’t identify reasons for the increased risk, testosterone worsens sleep apnea and affects blood platelets, linked to atherosclerosis and coronary plaque.
The authors urged more study on testosterone. Anne Cappola, an associate editor for the Journal of the American Medical Association, which published the study Tuesday, said men need to be made aware of the risks by their doctors, and questioned how the supplement is marketed.
Some “think it’s the fountain of youth. It’s going to give them back sexual performance, strength and endurance,” Cappola said. “The direct marketing of testosterone is playing into that. There needs to be that other voice saying there’s no medication out there with all benefit and no risk. There’s always a trade-off.”
Testosterone treatments are given through gels, patches and injections. Prescriptions for the supplements rose more than five-fold, to 5.3 million, in 2011 from 2000, the authors said.
About 5 million American men don’t produce enough of the hormone, according to the National Institutes of Health. A study in Europe published a decade ago found 1 in 5 men older than 50 has moderate-to-severe symptoms of testosterone deficiency. Fewer than 2 percent of cases outside the U.S. get treated, Malcolm Carruthers at London’s Centre for Men’s Health, wrote in a paper published in 2009.
AbbVie’s Androgel may generate $1.14 billion this year for the North Chicago, Ill.-based drugmaker, an increase from $874 million in 2011, according to data compiled by Bloomberg.
Lilly’s Axiron is expected to produce $168 million in 2013 sales, up from from $24 million in 2011, when the Indianapolis-based company introduced the drug.
Parsippany, N.J.-based Actavis Plc doesn’t list revenue for the Androderm patch.
AndroGel is approved by U.S. regulators to treat adult men with low or no testosterone who have been diagnosed with the condition, called hypogonadism, by a doctor. The drug has more than 10 years of “clinical, safety, published and post- marketing data, with its therapeutic risks well-documented in the prescribing label,” David Freundel, an AbbVie spokesman, said in an e-mail.
“We encourage discussion between physicians and patients that leads to proper diagnosis based on symptoms, lab tests and a patient’s other health needs,” Freundel said.
In an accompanying editorial, Cappola, an associate professor at the University of Pennsylvania in Philadelphia, said it remains unclear whether the finding can be generalized to a broader population of relatively healthy men. This includes those with so-called low T syndrome, where testosterone falls under certain levels, for anti-aging purposes or in younger men taking it for physical enhancement, she wrote.
An earlier study of testosterone supplements used in elderly males, funded by the U.S. National Institute on Aging and run at Boston Medical Center, was stopped in 2009 because an audit found it caused more heart attacks and high blood pressure.
Teresa Shewman, a Lilly spokeswoman, said the company is aware of cardiovascular events in men taking testosterone therapies.
“Lilly works with the scientific community and regulatory bodies to further understand and communicate the risks and benefits of testosterone replacement therapy,” Shewman said. “As a company responsible for developing medicines, Lilly is committed to providing advertising that is truthful, accurate and balanced. We encourage men to talk with their physician to weigh the benefits and risks before taking any prescription.”
The risk noted in the study was similar for men who had underlying heart conditions and those who didn’t, said Michael Ho, the senior researcher and a cardiologist at the Veterans Affairs Eastern Colorado Health Care System in Denver, who called the findings “a potential signal’ suggesting more research is needed,
‘‘I don’t know if the findings of this study would necessarily say that all men should not be on testosterone therapy,” Ho, who is also an associate professor of medicine at the University of Colorado at Denver, said. “It provides additional information that they can talk to their physician about.”