Endocrine Abstracts

Introduction: The recombinant GH receptor antagonist pegvisomant (PGV) is actually used for the treatment of acromegaly when surgery and medical therapy with somatostatin analogues (SSA) have failed. Long term safety and effectiveness need to be evaluated.

Material and methods: Retrospective analysis of clinical data from all patients treated with pegvisomant in a pituitary disorders unit.

Results: Thirteen patients are being treated with PGV in our unit. Medium time between diagnosis and beginning of PGV treatment is 90.71±92.75 months. Basal size of the tumours was 23±1.60 mm (80% macroadenomas). Before starting with PGV therapy, 63.6% of the patients had surgery and also 63.6% had radiotherapy. All the patients had been previously treated with SSA and two patients have combination treatment (SSA and PGV). Medium time of PGV treatment was 45.4±19.62 months (9–72). Medium dose of maintenance is 15±8 mg/24 h. (5–30). Medium IGF1 values measured at the beginning and after treatment stabilization were 873±551 (432–1769) vs 234±139 (116–464) (P<0.01). Normal IGF1 values (<300) were obtained in 72.7% of the cases, being necessary a mean time of treatment of 6.6 meses (2–36 months) and a mean dose of 15.8±4.9 mg. Tumor size or remaining tumor did not increase in any patient. There was clinical improvement in 100% of the cases. No side-effects have been found and we have found only one case of lipodistrofia.

Conclusion: Treatment with pegvisomant seems to be effective, safe and well-tolerated in our experience.