Ibutamoren may be beneficial for growth hormone deficiency and has been designated as an orphan drug (meaning the drug is allowed to be studied for a rare disease but is not yet approved) for growth hormone deficiency by the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA).[1][2]
Ibutamoren may have modest metabolic benefits. For example, a randomized controlled trial in older adults without known health conditions taking 25 mg of ibutamoren daily for 12 months showed a slight decrease in LDL cholesterol (−5.4 mg/dL) and a small increase in fat free mass (+1.1 kg) compared to taking a placebo. However, neither strength nor physical function were improved, and the small metabolic benefits did not last after ibutamoren was stopped.[3]
A randomized study of older adults recovering from hip fractures showed that taking 25 mg of ibutamoren daily for 24 weeks resulted in a slightly improved gait speed but did not improve any other measures of functional performance compared to a placebo.[4] There is also interest in ibutamoren for improving bone mass, but there’s no evidence to support this effect in people without growth hormone deficiency.[5]