Growth hormone therapy: emerging dilemmas

The history of pituitary growth hormone (GH) started 100 years ago but the isolation purification and determination of the chemical structure of the human GH (hGH) took another 50 years. Starting in 1957 hGH was extracted from cadaver pituitaries and its clinical use was restricted to severe GH deficient patient. With the invention of recombinant biosynthetic hGH in 1985; the indications for its use were extended. The major approved medications are GH deficiency and short statured children of various etiologies. This is a critical review of present and future use of human GH. To evaluate the effectiveness of the hGH treatment several pharmaceutical companies established postmarketing follow-up programs which are based on the reliability and cooperation of the treating physicians. Unfortunately they stop when the treatment is terminated and most studies refer to growth stimulation effectiveness during initial years but do not follow the children until final height. The long-term experience enabled to evaluate adverse effects (AE), the majority being due to large dosage. The most serious AE reported are increases in malignancies and early or late mortality in adult age. There is consensus that GH deficient children need replacement therapy. As long-term hGH treatment is expensive and the final height gains in non-GH deficient children small the cost-benefit indications to treat short children without a disease has been questioned. To avoid the need of daily injections, long-acting hGH preparations undergo clinical trials. The future will show their effectiveness and eventual adverse effects.