Biosynthetic human growth hormone in the treatment of growth hormone deficiency

Long-term therapy with recombinant human growth hormone (Saizen) in children with idiopathic and organic growth hormone deficiency

In an open-label study, 69 children with organic or idiopathic growth hormone deficiency (GHD) were treated with recombinant human growth hormone (Saizen) for an average of 64.4 mo, with treatment periods as long as 140.9 mo. Auxologic measurements, including height velocity, height standard deviation score, and bone age, were made on a regular basis. The data suggest that long-term treatment with Saizen in children with GHD results in a positive catch-up growth response and proportionate changes in bone age vs height age during treatment. In addition, long-term Saizen therapy was well tolerated, with the majority of adverse events related to common childhood disorders or existing baseline medical conditions and not to study treatment. There were no significant changes in laboratory safety data or vital signs, and no positive antibody tests for Saizen.

Recombinant human growth hormone: old and novel uses

Recent studies of the growth hormone insulinlike growth factor I (IGFI) axis suggest that these hormones are involved in several physiologic processes, in addition to growth. Thus, several lines of evidence indicate an increasingly important role for recombinant human growth hormone as a part of the modern therapeutic armamentarium. In addition to the treatment of children with growth hormone deficiency, administration of growth hormone appears to be of considerable benefit to girls with Turner syndrome, children with chronic renal failure, and adults with growth hormone deficiency or human immunodeficiency virus (HIV) wasting syndrome. Moreover, its therapeutic use is being investigated in other conditions, such as children with idiopathic short stature, the healthy elderly, and the critically ill. However, long-term surveillance among growth hormone recipients is needed to fully evaluate its risk-benefit profile.

Unfavorable effects of growth hormone therapy on the final height of boys with short stature not caused by growth hormone deficiency

A group of 18 boys with non-growth hormone (GH)-deficient short stature without GH therapy (group A) and another group of 9 boys with non-GH-deficient short stature with GH therapy in doses of 0.5 IU (0.17 mg)/kg per week administered 5 to 6 times weekly (group B) were observed until they reached their final height. The mean duration of GH therapy was 4.2 years (range 3.2 to 5.0 years). These two groups were matched with respect to their standard deviation score (SDS) for bone age at the start of observation. Mean +/- SD of the final height for group A and group B was 162.0 +/- 5.4 cm and 154.2 +/- 4.2 cm, respectively. During the prepubertal period, height SDS for bone age of these two groups was not affected by GH therapy. During the pubertal period, however, height SDS for bone age remained constant for group A but decreased gradually for group B. Our observation indicates that for boys with non-GH-deficient short stature GH therapy does not improve height SDS for bone age during the prepubertal period, and in fact reduces it during the pubertal period, possibly resulting in a shorter final height than might have been attained naturally.

Guidelines for the use of growth hormone in children with short stature. A report by the Drug and Therapeutics Committee of the Lawson Wilkins Pediatric Endocrine Society

On the basis of the information currently available, the only conditions in which GH therapy appears to be safe and effective in increasing adult height are GH deficiency and, likely, Turner syndrome. Therapy with GH also increases the growth velocity of children with CRI and may increase adult height, but no long-term data are available. Encouraging short-term results have been reported in patients with a few other conditions, such as patients with glucocorticoid-induced growth failure, renal transplantation, and Prader-Willi syndrome, but the data are limited and no long-term studies have been reported; in many other conditions the data are either inconclusive or discouraging. For children in these latter groups, GH therapy should be considered investigational and undertaken only as part of ethically sound, controlled clinical trials. Knowledge concerning the conditions in which GH is safe and effective is a prerequisite to making rational decisions concerning its use. However, in deciding whether therapy is warranted in an individual child, one must consider other important factors. The age and emotional maturity of the child, the family structure and dynamics, and even financial considerations may, in some cases, outweigh the presence of a GH-responsive condition. Likewise, the child's and the family's views about "short" stature and the likely benefits of therapy must be considered. Ultimately, a decision concerning the appropriateness of GH therapy must be individualized and based on a realistic assessment of its impact on the quality of life of the child and future adult.

Influence of spontaneous or induced puberty on the growth promoting effect of treatment with growth hormone in girls with Turner's syndrome

OBJECTIVE

The aim was to evaluate the effect of 3 years treatment with recombinant human growth hormone (rhGH) on height velocity and height in girls with Turner's syndrome (TS) and to study to influence of spontaneous or induced puberty on the growth promoting effect of rhGH.

PATIENTS AND DESIGN

The investigation was performed in 36 girls with Turner's syndrome treated for 3 years with rhGH in a dose of 1 IU/kg week, administered as daily subcutaneous injections. Fifteen patients remained prepubertal throughout the observation period (Group 1). During the first 2 years of rhGH therapy, four girls developed puberty spontaneously (Group 2). During the 3rd year of rhGH treatment puberty was induced with 100 ng/kg day ethinyl oestradiol orally in 17 girls requesting pubertal development and with a bone age of at least 11 'years' (Group 3).

RESULTS

During the first year of rhGH therapy height velocity increased significantly in all patients. Mean +/- SD height velocity was higher in the four patients with Turner's syndrome who developed spontaneous puberty than in 17 age-matched girls with Turner's syndrome without puberty (8.9 +/- 1.2 vs 7.4 +/- 1.2 cm/year; P < 0.05). During the second and third year of rhGH treatment height velocity decreased in all patients but remained above baseline levels. The induction of puberty with 100 ng/kg day ethinyl oestradiol in the patients of Group 3 did not lead to an acceleration of height velocity, but seemed in contrast to decelerate height velocity. After 3 years of rhGH treatment, 21 out of 36 patients have obtained a height at or above the initially calculated projected adult height and five girls are already taller than 150 cm.

CONCLUSIONS

The onset of spontaneous puberty during the first years of rhGH treatment seems to have an additive effect to rhGH on height velocity. Induction of puberty with oral administration of 100 ng/kg day ethinyl oestradiol did not have any beneficial effect on height velocity and seems therefore not to be the optimal way to induce puberty with an adequate pubertal growth spurt in girls with Turner's syndrome under rhGH therapy. Different doses and routes of oestrogen administration have to be evaluated in order to mimic the growth promoting effect of spontaneous puberty as well as possible.

Biosynthetic growth hormone therapy in children with growth hormone deficiency: experience at AIIMS, New Delhi

A total of 20 previously untreated children with growth hormone deficiency (GHD) were treated for one year with biosynthetic human growth hormone (hGH). The mean chronologic age was 9.43 +/- 3.52 years with a height age of 5.02 years, and bone age 9.43 +/- 3.52 (TW2-RUS) 6.42 years. The mean pretreatment growth velocity was 2.43 +/- 0.90 cm/year. Of these 14 children had complete GHD (peak GH levels less than 5 ng/ml) and 6 had partial GHD. They were treated with recombinant GH in a dose of 0.5 IU/kg/week divided into 6-7 injections per week subcutaneously at night. The mean growth velocity increased to 8.88 +/- 2.10 cm/yr at the end of 6 months and 8.00 +/- 2.21 cm/yr at 12 months. The actual gain ranged from 6-11 cm in a year. There were no local adverse reactions. One child developed vitiligo of the face and another transient hyperglycemia.