EFFECT OF LONG-TERM RECOMBINANT GROWTH-HORMONE THERAPY IN CHILDREN - THE NATIONAL COOPERATIVE GROWTH STUDY, USA, 1985-1994

Over a 9-year period (1985-1994) approximately 20,000 children receive d recombinant human growth hormone (rhGH) while enrolled in the Nation al Cooperative Growth Study (NCGS), an observational, longitudinal stu dy designed to monitor the long term efficacy and safety of rhGH admin istered to children in North America. Forty-four percent of the patien ts had idiopathic growth hormone deficiency (IGHD), 13.8% organic GHD (OGHD), 25% idiopathic short stature (ISS), 9.9% Turner's syndrome (TS ), and 7.3% miscellaneous disorders. Eighty-five percent of the patien ts enrolled were Caucasian, and approximately two-thirds of the non-Tu rner patients were male. For the subset of patients treated for at lea st 4 years and who were prepubertal throughout this period (IGHD N=308 , OGHD N=93, ISS N=169, TS N=82), mean growth rates increased in all p atient categories and remained at or above pretreatment growth rates t hrough 4 consecutive years of therapy with rhGH. Growth rates during a dministration of rhGH were greater in children in whom the pretreatmen t maximum stimulated GH concentration was less than or equal to 3 mu g /l, Patients treated with 6 or 7 doses of rhGH each week grew more rap idly than did those receiving thrice weekly dosages, although the rati os of the increment in bone age to the increment in height age after t wo years of therapy were similar in the two treatment regimens, For pa tients treated with rhGH for 7 consecutive years, the mean height stan dard deviation scores increased by 2.5 in IGHD (N=169), 2.0 in OGHD (N =50), 1.9 in ISS (N=69), and 1.3 in TS (N=19), but remained below targ et heights in all categories. It is concluded that administration of r hGH increases growth rates in patients with IGHD, OGHD, ISS, and TS, a nd that this stimulatory effect can persist for at least 4 years.