Urologists should spearhead testosterone trials

October 1, 2004

New York--It is up to urologists to take the lead in conducting clinical trials to define the safety and benefits of testosterone therapy in older men, according to E. Darracott Vaughan, Jr, MD. Dr. Vaughan, one of two urologists who served on an Institute of Medicine committee assessing the need for clinical trials of testosterone replacement, provided an update on the committee's report and its significance to urologists during the AUA annual meeting.

"I think this is a very important area for urologists to be interested in," said Dr. Vaughan, professor and chairman emeritus of urology at Weill Medical College of Cornell University, New York. "We will have cooperation and competition from geriatricians, but I hope [urologists] will be interested."

The request for the review came against a background of growing use of testosterone therapy, much of which was felt to be off label, Dr. Vaughan said.

"We're not talking about treatment of clinically hypogonadal men. We're talking about testosterone supplementation or replacement in the aging male or the male over age 65," he said.

The IOM committee reviewed four areas:

The committee's literature review identified 31 placebo-controlled trials of testosterone therapy in middle-aged and older men. The trials had small sample sizes, ranging from six to 108 participants. Only six trials had at least 50 patients. Treatment duration was generally brief-•6 months in 25 of the 31 trials. The trials used a variety of testosterone preparations, although intramuscular injection was the most common route of administration (18 of 31 trials).

The trials evaluated various health-related outcomes (see "Health outcomes assessed," below). The committee found that placebo-controlled trials provided no clear evidence of a benefit of testosterone therapy.

The path of future studies The committee members concluded that future studies of testosterone therapy should focus on the patient populations that are most likely to benefit and should use testosterone as a therapeutic intervention, not as a preventive measure. Studies should clearly establish that a benefit exists before assessing long-term risks.

Clinical outcomes of trials should be those endpoints for which a suggestion of efficacy exists and for which safe and effective therapeutic options are not currently available. Examples include weakness and disability, sexual dysfunction, cognitive dysfunction, impaired vitality, well being, and quality of life.