Plasma integrated concentration of growth hormone after recombinant human growth hormone injection. Implications for

S A Chalew1, M Phillip, A A Kowarski

  • 1Division of Pediatric Endocrinology, University of Maryland School of Medicine, Baltimore 21201.

Insights

Recombinant growth hormone therapy significantly increases growth hormone levels and insulin secretion in children with growth deficiency. These hormonal changes may be relevant for patients with insulin resistance or those on higher growth hormone doses.

Area of Science:

  • Pediatric Endocrinology
  • Pharmacokinetics
  • Metabolic Studies

Background:

  • Growth hormone (GH) therapy is crucial for children with GH deficiency and poor linear growth.
  • Understanding the pharmacokinetic and metabolic effects of standard GH doses is essential for optimizing treatment.

Purpose of the Study:

  • To evaluate the impact of a standard dose of injected recombinant human growth hormone (rhGH) on integrated GH and insulin concentrations.
  • To assess the pharmacokinetic profile of rhGH after subcutaneous injection in pediatric patients.

Main Methods:

  • A cohort of 12 growth hormone-deficient children received subcutaneous rhGH (0.06 mg/kg) three times weekly.
  • Integrated GH and insulin concentrations were measured before therapy and at 6 months post-initiation, specifically during a GH injection day.

Main Results:

  • Post-treatment integrated GH concentrations were significantly elevated compared to pre-treatment levels and those in normally growing children (P < .001).
  • Pharmacokinetic analysis revealed a peak GH level of 53.7 ± 24.1 µg/L with a half-life of 3.0 ± 0.7 hours.
  • Integrated insulin concentrations significantly increased after rhGH injection (33.4 ± 9.5 mU/L) compared to baseline (19.0 ± 10.9 mU/L; P < .0008).

Conclusions:

  • Standard rhGH injections lead to substantially higher integrated GH levels than observed in healthy children, accompanied by increased insulin secretion.
  • The observed hormonal shifts may have clinical implications for pediatric patients with insulin resistance or those requiring higher rhGH dosages.
Abstract

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