INTRANASAL ADMINISTRATION OF THE GHRP HEXARELIN ACCELERATES GROWTH INSHORT CHILDREN

OBJECTIVE Hexarelin is a recently synthesized small growth hormone rel easing peptide (GHRP) (His-D-5-methyl-Trp-Ala-Trp-D-Phe-Lys-NH2). It i s active by intravenous, oral and intranasal administration in animals and man. The aim of this study was to find out whether longterm admin istration of this peptide would promote growth in short children. DESI GN AND PATIENTS Intranasal hexarelin was administered in a dose of 60 mu g/kg thrice daily to 8 prepubertal short children aged 4-11.6 years for periods of up to 8 months. RESULTS Hexarelin treatment stimulated insulin-like growth factor-1 (IGF-1) secretion raising the level from 10.4 +/- 3.9 (SD) to 14.1 +/- 4.6 nmol/l (P < 0.004). The rise in IGF -l led to a significant increase in the mean (+/- SD) linear growth ve locity from 5.3 +/- 0.8 to 8.3 +/- 1.7 cm/year (P < 0.0001). There was also a significant decrease in skinfold thickness despite increase in body weight and an increase in head circumference. Additional finding s were a rise in serum phosphate from 1.5 +/- 0.1 to 1.8 +/- 0.1 mmol/ l (P < 0.004) and of alkaline phosphatase from 219 +/- 74 to 261 +/- 7 5 U/l (P < 0.05). CONCLUSIONS The long-term GH/IGF-I stimulating, anab olic and growth promoting effects achieved by intranasal administratio n of this hexapeptide, seemingly without undesirable side-effects, sug gests clinical potential for this new class of drugs.