(Reuters) - An advisory panel to the U.S. Food and Drug Administration was sharply divided on Thursday over whether a drug made by Endo Health Solutions Inc can safely be prescribed for men with low testosterone.
A panel of outside medical experts split 9-9, with some members saying the drug, Aveed, offers a valuable alternative to existing products, especially since it is already sold under the brand name Nebido outside the United States.
Dr. William Cooper, professor of pediatrics and preventive medicine at Vanderbilt University School of Medicine, said he did not find anything in the data "of a magnitude that would make me concerned about the overall safety of the drug."
Others were troubled by the risk associated with the drug of allergic reactions, which are not always predictable.
"I think there's a real absence of data to prove it's truly safe," said Dr. Lewis Nelson, director of the fellowship in medical toxicology at New York University School of Medicine.
Testosterone is a hormone produced in the testicles that is responsible for maintaining muscle bulk, bone growth and sexual function. Symptoms of low testosterone can include loss of libido, depression, decreased muscle mass and fatigue.
Treatments currently include testosterone skin patches, short-acting injections and topical gels. Aveed is a long-acting version designed to be given once every 10 weeks compared with once every two to four weeks for existing injections.
The panel overwhelmingly agreed that Endo's proposed plan for managing the drug's risks if it were approved is insufficient.
The company has offered to instruct physicians to inject the drug slowly and to make patients wait 30 minutes before leaving the doctor's office. Some panelists recommended the drug be administered only in clinics where specialists would be on hand in case of an adverse reaction.
Others expressed concern that the drug, if approved, would be used more widely than intended by athletes and others seeking to enhance performance.
Aveed has twice before been rejected by the FDA based on concerns about injection-site reactions and the potential for pulmonary oil microembolisms. Aveed is made of testosterone and castor oil and the FDA has expressed concern of a risk that the oil could cause blockages in blood vessels in the lungs.
Mark Woods, director of the pharmacy department at St. Luke's Hospital in Kansas City, voted in favor of the drug's safety but conceded he was "very conflicted."
"I do share the concerns about safety but I also believe, based on some of the things we've heard from our experts and consumers, that there probably is a strong need for a long acting alternative."
Analysts were not expecting the drug to receive a warm welcome from the panel, based on the negative tone of the initial FDA staff review.
Endo's shares closed down 0.6 percent to $35.75 on Nasdaq.
(Reporting by Toni Clarke in Washington; Editing by Phil Berlowitz)