When the TRAVERSE trial published its primary results in 2023, it was widely described as the most rigorous look ever taken at the cardiovascular safety of testosterone replacement therapy. Two years later, with follow up data, real world reporting, and a regulatory response now in hand, the conclusions have only strengthened.
What TRAVERSE Was Designed to Answer
TRAVERSE, short for "Testosterone Replacement Therapy for Assessment of Long term Vascular Events and Efficacy Response in Hypogonadal Men," enrolled more than 5,000 men aged 45 to 80 with confirmed low testosterone and either preexisting cardiovascular disease or significant risk factors. Participants were randomly assigned to receive transdermal testosterone gel or a placebo gel and followed for an average of 33 months (HealthSpectra TRAVERSE summary).
The primary endpoint was a composite of death from cardiovascular causes, nonfatal heart attack, and nonfatal stroke. The trial was specifically designed to prove or disprove the cardiovascular safety concerns raised by earlier observational studies.
The Headline Result
Major adverse cardiovascular events occurred in 7.0 percent of the testosterone group and 7.3 percent of the placebo group. The difference was not statistically significant, and TRT met the prespecified standard for noninferiority (HealthSpectra TRAVERSE summary).
Translating that result for patients: in this large, carefully run trial, men taking testosterone did not have more heart attacks, strokes, or cardiovascular deaths than men taking placebo.
What About Secondary Findings
TRAVERSE also tracked a range of secondary outcomes, and not everything was reassuring. Researchers observed slightly higher rates of pulmonary embolism, acute kidney injury, and atrial fibrillation in the testosterone group. These signals were not large enough to overturn the primary cardiovascular finding, but they reinforce the importance of careful patient selection and monitoring.
A subanalysis on sexual function found that men on testosterone reported a 25 percent greater increase in sexual activity than those on placebo, the clearest treatment benefit observed in the trial (Medscape, 2026).
Regulatory Response
The FDA acted on the TRAVERSE data in February 2025 by removing the cardiovascular black box warning from testosterone product labels (Healthline, 2025). A December 2025 FDA expert panel went further, recommending broader access reforms and citing TRAVERSE as the key piece of evidence that earlier safety concerns had been overstated (RAPS, 2025).
