Acute and long-term effects of SMS 201-995 in acromegaly.

The subcutaneous administration of 50 micrograms SMS 201-995 at 0815 h in 18 acromegalic patients reduced plasma growth hormone (GH) levels from 2 to 6 h after injection from 36 +/- 2 to 7 +/- 1 microgram/l (-80 +/- 5%). Circulating GH concentrations had normalized to less than 5 micrograms/l during this period in 11 of 18 patients. Postprandial blood glucose levels after breakfast were significantly (p less than 0.01) higher after SMS administration but significantly lower (p less than 0.01) after supper. Chronic treatment of five acromegalic patients with 200-300 micrograms SMS 201-995 daily for 8-24 weeks resulted in a rapid clinical improvement in all patients and complete disappearance of the complaints in four of five patients. This was accompanied by tumour shrinkage as estimated by computerized tomography scanning in three of four patients. In parallel, mean plasma GH levels and serum somatomedin-C and phosphorus levels fell to or within the normal values. SMS 201-995 represents a new tool in the medical management of acromegaly and may become the treatment of choice, especially in patients who do not benefit sufficiently from surgery and/or radiotherapy.