Testosterone undecanoate is very slow-acting injectable form of the androgen testosterone. Following deep intramuscular injection, the drug provides a sustained release of testosterone into the bloodstream for up to 10 weeks. Testosterone undecanoate has been available under the brand name Nebido for over 10 years in more than 80 countries. However, it was not approved for use in the US.
Recently, however, the US FDA approved injectable testosterone undecanoate (2014). Endo Pharmaceuticals will market it under the brand name Aveed. Aveed is a depot formulation of testosterone undecanoate (TU) indicated for long-term TRT. Testosterone injections of 750 mg Aveed maintain normal levels between 300 and 1000 ng/dL for up to 10 weeks. Following baseline administration of 750 mg, a second 750 mg dose is given at 4 weeks followed by 750 mg every 10 weeks thereafter.
Due to the very slow-acting nature, Aveed will offer men with low testosterone levels a more convenient treatment option than currently available preparations. The injection interval for TU, after the loading dose, is 10 weeks. This equates to approximately 5 injections per year. In comparison, testosterone gels require daily dosing and TE and TC require 2 intervals (26 injections per year.