Treatment escape reduces the effectiveness of cabergoline during long-term treatment of acromegaly in monotherapy or in association with first-generation somatostatin receptor ligands.

Abstract

Few studies evaluated the use of cabergoline (CAB) for acromegaly treatment in monotherapy or in combination with first-generation somatostatin receptor ligands (SRLs). To evaluate the efficacy, predictors of response and safety of CAB treatment in acromegaly both in monotherapy and in combination with SRLs. We retrospectively collected demographic, biochemical, tumour and treatment data. Short-term disease control was defined as random GH level < 1.0μg/L and normal age-matched IGF-I level after 3-6months of treatment with the higher dose used. Long-term disease control was defined as maintenance of normal GH and IGF-I levels at the last visit (at least 9months of treatment). Eighty-two patients were studied. The median total time of treatment in monotherapy or in combination with SRLs was 14months (3-124) and 34months (3-88), respectively. Short-term disease control was observed in 6 (21%) patients in the monotherapy group and in 20 (32%) in the combination group. Treatment escape was observed in 1 patient after 16months of CAB monotherapy and in 6 (30%) patients with combination therapy (after a median of 38months), resulting in long-term disease control of 18% and 23%, respectively. Hyperprolactinemia was a predictor of response to monotherapy and pretreatment GH level to combination treatment. We presented the results of the largest single-centre study with CAB in monotherapy and in combination with SRL. The efficacy of CAB in acromegaly seems to be lower than that of other drugs, and treatment escape may occur after a long-term follow-up.