An individualized GH dose regimen for long-term GH treatment in Japanese patients with adult GH deficiency.
OBJECTIVE
To investigate the effects of growth hormone (GH) treatment, using a dose-adjustment regimen based on serum insulin-like growth factor (IGF)-I concentrations, in adult Japanese hypopituitary patients with GH deficiency.


METHODS
Japanese patients who had initially been administered GH (n = 31) or placebo (n = 28) in a 24-week double-blind study received individualized GH treatment in an open-label study for 48 weeks. Body composition from dual-energy X-ray absorptiometry (DXA) and serum IGF-I, IGF-binding protein 3 (IGFBP-3) and lipid levels were determined centrally.


RESULTS
Significant increases in lean body mass (4.5%) and decreases in fat mass (-10.5%) were observed in the group that received individualized GH doses in the present open-label study following placebo in the double-blind study. This was comparable with the changes observed in these parameters (4.7 and -9.2%, respectively) with fixed-dose GH treatment in the double-blind study; this latter group maintained these improvements throughout the open-label study. Individualized dose adjustment allowed for more moderate dose increases than the fixed-dose titration method. Individualized dosing also resulted in a lower mean dose for adult-onset compared with childhood-onset GH-deficient patients (0.032+/-0.019 versus 0.061+/-0.023 mg/kg per week for patients treated with GH for 48 weeks in the open-label study following placebo in the double-blind study). Dosing patterns in the two groups were paralleled by the changes in IGF-I and IGFBP-3. The incidence of oedema and cases with high IGF-I level were less frequent under the IGF-I controlled regimen compared with those during the fixed-dose titration method.


CONCLUSIONS
Individualized GH administration based on IGF-I levels was safe and effective. This regimen demonstrated differences in dose requirements between adult- and childhood-onset patients. An individualized dose regimen is recommended in adult Japanese GH-deficient patients.
Chihara
Kazuo
K
Department of Clinical Molecular Medicine, Kobe University Graduate School of Medicine, Kobe, Japan. chiharak@med.kobe-u.ac.jp
Koledova
Ekaterina
E
Shimatsu
Akira
A
Kato
Yuzuru
Y
Kohno
Hitoshi
H
Tanaka
Toshiaki
T
Teramoto
Akira
A
Bates
Peter C
PC
Attanasio
Andrea F
AF
D000328:Adult; D002784:Cholesterol / Q000097:blood; D005260:Female; D019382:Human Growth Hormone / Q000008:administration & dosage* / Q000009:adverse effects / Q000172:deficiency*; D006801:Humans; D007018:Hypopituitarism / Q000097:blood / Q000188:drug therapy*; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D007564:Japan; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome
D018972:Insulin-Like Growth Factor Binding Protein 3; D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I; D002784:Cholesterol