A long-acting human growth hormone (Nutropin Depot): efficacy and safety following two years of treatment in children with growth hormone deficiency.

BACKGROUND

Nutropin Depots [somatropin (rDNA origin) for injectable suspension] is a long-acting form of human growth hormone (GH) to be administered by subcutaneous (s.c.) injection. The availability of this formulation offers the opportunity for greater convenience and compliance by decreasing the number of injections and frequency of administration required.

OBJECTIVE

To determine the efficacy and safety of a long-acting formulation of GH administered in children with GH deficiency (GHD) once or twice monthly for 2 years.

PATIENTS

Fifty-six previously untreated, prepubertal children with GHD received Nutropin Depot 1.5 mg/kg once monthly (1x/mo), or 0.75 mg/kg twice monthly (2x/mo) for 24 months. The mean pretreatment growth rate was 5.0 +/- 2.4 cm/yr.

RESULTS

The 0-12 mo growth rate (mean +/- SD) was 8.3 +/- 1.5 cm/yr in the 1x/mo group and 8.2 +/- 2.0 cm/yr in the 2x/mo group. The 12-24 month growth rate was 7.2 +/- 1.5 cm/yr in the 1x/mo group and 6.9 +/- 1.5 cm/yr in the 2x/mo group. During the 24 months of treatment, height standard deviation score (SDS) increased by 1.0 +/- 0.5 SD in the two groups combined (p <0.0001). The corresponding advancement in bone age was 2.2 +/- 0.7 yr, resulting in a gain in Bayley-Pinneau predicted adult height (PAH) SDS of 0.6 +/- 0.9 SD in the 1x/mo group and 0.6 +/- 1.0 SD in the 2x/mo group. No serious adverse events attributable to the study drug were reported. Injection site reactions were common, but resolved without intervention. Pre-dose fasting and postprandial glucose and insulin levels, as well as hemoglobin A1c levels, were unchanged from baseline values.

CONCLUSIONS

Treatment with Nutropin Depot is associated with catch-up growth and normal skeletal maturation and is a viable alternative to daily injections of GH in children with GHD.