Effects of an oral growth hormone secretagogue in older adults.
BACKGROUND
GH secretion declines with age, possibly contributing to reduced muscle mass, strength, and function. GH secretagogues (GHS) may increase muscle mass and physical performance.


OBJECTIVE
We conducted a randomized, double-masked, placebo-controlled, multicenter study to investigate the hormonal, body composition, and physical performance effects and the safety of the orally active GHS capromorelin in older adults with mild functional limitation. INTERVENTION/PARTICIPANTS: A total of 395 men and women aged 65-84 yr were randomized for an intended 2 yr of treatment to four dosing groups (10 mg three times/week, 3 mg twice a day, 10 mg each night, and 10 mg twice a day) or placebo. Although the study was terminated early according to predetermined treatment effect criteria, 315 subjects completed 6 months of treatment, and 284 completed 12 months.


RESULTS
A sustained dose-related rise in IGF-I concentrations occurred in all active treatment groups. Each capromorelin dose prompted a rise in peak nocturnal GH, which was greatest with the least frequent dosing. At 6 months, body weight increased 1.4 kg in subjects receiving capromorelin and decreased 0.2 kg in those receiving placebo (P = 0.006). Lean body mass increased 1.4 vs. 0.3 kg (P = 0.001), and tandem walk improved by 0.9 sec (P = 0.02) in the pooled treatment vs. placebo groups. By 12 months, stair climb also improved (P = 0.04). Adverse events included fatigue, insomnia, and small increases in fasting glucose, glycosylated hemoglobin, and indices of insulin resistance.


CONCLUSIONS
In healthy older adults at risk for functional decline, administration of the oral GHS capromorelin may improve body composition and physical function.
White
Heidi K
HK
Duke University School of Medicine and Geriatric Research Education and Clinical Center, Durham Veterans Affairs Medical Center, Durham, North Carolina 27710, USA. White031@mc.duke.edu
Petrie
Charles D
CD
Landschulz
William
W
MacLean
David
D
Taylor
Ann
A
Lyles
Kenneth
K
Wei
Jeanne Y
JY
Hoffman
Andrew R
AR
Salvatori
Roberto
R
Ettinger
Mark P
MP
Morey
Miriam C
MC
Blackman
Marc R
MR
Merriam
George R
GR
D000284:Administration, Oral; D000368:Aged; D000369:Aged, 80 and over; D001823:Body Composition / Q000187:drug effects; D004311:Double-Blind Method; D005260:Female; D006304:Health Status; D019382:Human Growth Hormone / Q000097:blood / Q000378:metabolism*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008297:Male; D010880:Piperidines / Q000627:therapeutic use*; D010919:Placebos; D011720:Pyrazoles / Q000627:therapeutic use*; D012449:Safety
C433143:CP 424391; D010880:Piperidines; D010919:Placebos; D011720:Pyrazoles; D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I