A study published in the Journal of the American Medical Association found that injectable testosterone results in fewer cardiovascular adverse events than gel- or patch-based formulations, offering hope that new forms of drug delivery can rekindle a once-hot market that's been stalled by the FDA's safety concerns.
"There's a large spike of serum testosterone that happens after an injection, so the injections may carry a slightly higher cardiovascular risk," lead author Dr. J. Bradley Layton, of the University of North Carolina, told Medscape, adding that the "The US Food and Drug Administration has just ruled that testosterone is really indicated and approved only for men with very specific endocrine disorders and not just general age-related decreases in testosterone."
Meanwhile, Dr. Margaret Wierman, from the Denver Veterans Affairs Medical Center wrote in an accompanying editorial that the results favor guidelines restricting testosterone therapy to men who have hypogonadism, not just low testosterone levels, or "low T" as the industry prefers to call it in their promotions.
The one-year risk of heart attack or stroke, hospitalization or death was 1.16%-1.34% among testosterone injection users, compared to rates between 1.02%-1.1% among patch users.
The study abstract concludes that, "Testosterone injections were associated with a greater risk of cardiovascular events, hospitalizations, and deaths compared with gels. Patches and gels had similar risk profiles. However, this study did not assess whether patients met criteria for use of testosterone and did not assess the safety of testosterone among users compared with nonusers of the drug."