BY WILLIAM LLEWELLYN HRT Rx
Nebido (testosterone undecanoate injection) is a relatively new long-acting testosterone injection, which is already available in many other parts of the world. It is currently under investigation in the United States. On that subject, the results of a three-year study into the safety and effectiveness of this drug in middle-aged men was just published in the journal Aging Male (1). Sixty men (mean age of 57 years) were selected for the study, each suffering from late-onset hypogonadism (low testosterone), obesity, and metabolic syndrome. Forty of these men were given a recommend course of Nebido to correct the hormone deficiency, which involved four injections per year. The remaining twenty men were not candidates for testosterone treatment, and thus were used as controls.
At the start of the study, the men (in general) suffered from mild osteopenia. This refers to a reduced level of bone mass, though less severe than osteoporosis. After testosterone treatment, BMD significantly improved at a rate of approximately 5% per year. There was also a significant reduction in C-reactive protein (hs-CRP), a marker of inflammation. This should reflect a substantial improvement in symptoms or diagnosis of metabolic syndrome. No serious side effects were reported during the study, though the adherence to the testosterone injections over the three-year period was only about 50%.
Some patients in Europe have been complaining about uncomfortable injections with Nebido. For them, the 4 mL volume is perhaps a bit too much. Others find that their hormone levels are better stabilized with more frequent injections of drugs like testosterone cypionate or enanthate. These reports may underline an issue with patient compliance. Testosterone undecanoate was still well tolerated, and resulted in significant metabolic and physical improvements in the men that remained in treatment. Therefore, this study does continue to support the potential efficacy and safety of Nebido for testosterone replacement therapy. The future of this drug in the U.S., however, remains uncertain.
(1) Effects of long-acting testosterone undecanoate on bone mineral density in middle-aged men with late-onset hypogonadism and metabolic syndrome: results from a 36 months controlled study. Aversa A, Bruzziches R et al. Aging Male. 2012 Mar 23