Endocrine Abstracts

Whilst surgery and external beam radiotherapy remain cornerstones of the management of acromegaly, recent guidelines have emphasised the importance of adjunctive medical therapy [e.g. with somatostatin receptor ligands (SRLs), dopamine agonists, growth hormone (GH) receptor antagonists] in attaining 'safe' GH and insulin like growth factor 1 (IGF-1) levels, especially in patients who are not 'cured' following primary intervention. Several studies have established the efficacy of SRLs in lowering GH and IGF-1 to levels which are no longer associated with excess morbidity and mortality. Here, we report our initial experience with the novel long-acting SRL Lanreotide Autogel (LA) in achieving satisfactory GH and IGF-1 levels in patients with evidence of persisting disease activity following primary treatment.

Fifteen subjects (9 male, 5 female; age 22-74 yrs) with acromegaly, who had undergone initial treatment with surgery (n=13) and/or radiotherapy (n=5), were studied. 9 patients had previously received long-acting octreotide. LA therapy was commenced with measurement of IGF-1 and mean daytime GH levels at base line, 4, 8, and 12 months post-treatment. Overall, there was a significant improvement in disease control with reductions in both mean GH (baseline 8.1 mU/L, 12months 6.8mU/L) and IGF-1 [baseline 155% upper limit of normal (ULN), 12mths 125% ULN] levels. Subjects previously treated with long acting octreotide had lower baseline mean GH (4mU/L) and achieved safe levels (3.4 mU/L), with near normalisation of IGF1 (112% ULN) by 12months; in contrast, patients not previously treated with long acting octreotide had higher baseline mean GH levels (14.8mU/L) and responded less well to treatment (12months: mean GH 12.9 mU/L, IGF-1 146% ULN). We conclude that LA is an effective adjunctive therapy in acromegaly, with efficacy comparable to other SRLs. For patients with residual disease activity despite maximal LA therapy, further surgical, medical and, where appropriate, radiotherapy-based treatment options are being considered.