Over 12 months, the ghrelin mimetic MK-677 enhanced pulsatile growth hormone secretion, significantly increased fat-free mass, and was generally well tolerated. Long-term functional and, ultimately, pharmacoeconomic, studies in elderly persons are indicated. In this randomized trial, 65 healthy older adults were assigned to receive placebo or MK-677, an oral ghrelin mimetic that increased pulsatile growth hormone secretion to young-adult levels. Over 1 year, lean fat-free mass increased 1.1 kg with MK-677 and decreased 0.5 kg with placebo. MK-677 did not affect strength and function, but insulin sensitivity declined and mean serum glucose levels increased 0.28 mmol/L (5 mg/dL).
daily dose of an investigational medication has been found to restore muscle mass in the arms and legs of older adults and improve some of their biochemistry to levels found in healthy young adults, suggesting an anti-frailty drug has been found.
The drug, called MK-677, was evaluated for its safety and effectiveness in a study that showed the drug restored 20 percent of muscle mass loss associated with normal aging. In fact, levels of growth hormone (GH) and of insulin-like growth factor I (IGF- I) in healthy seniors who took the drug increased to the levels found in healthy young adults, said Michael O. Thorner, a professor of internal medicine and neurosurgery at the University of Virginia Health System