Objective  This prospective randomized study evaluated the efficacy and safety of octreotide LAR vs. surgery in newly diagnosed acromegalic patients.

Methods  Totally 104 male and female patients were enrolled in a 50‐week, exploratory, open‐label and randomized study. Eligible patients were randomized to receive either octreotide LAR 20 mg every 28 days or to undergo surgery. Efficacy was assessed by changes in mean GH and IGF‐I serum concentrations, at weeks 12, 24 and 48. Tumour volume was assessed by contrast‐enhanced MRI. In both groups, treatment adjustment was performed for patients uncontrolled at week 12 or 24. Octreotide LAR patients received a dose increased to 30 mg or, if already receiving this dose, investigator and patients could decide to cross‐over to surgery. Patients uncontrolled after surgery received octreotide LAR 20 mg, increased to 30 mg if acromegaly was still uncontrolled.

Results  Overall success rates at weeks 24 and 48 were 25% and 28% for the octreotide LAR group and 49% and 39% for the surgery group. Only the difference observed at week 24 was statistically significant (P = 0·047). Both groups had a significant (> 20%) tumour shrinkage: 73% of patients in the octreotide LAR group and 95% in the surgery group. Major differences between octreotide LAR and surgery group in the occurrence of adverse events were gastrointestinal (71%vs. 27%), hepatobiliary (41%vs. 8%) and respiratory (5%vs. 28%).

Conclusion  This first randomized study in unselected patients indicates that the 48‐week treatment outcome of octreotide LAR as first‐line treatment of acromegaly does not significantly differ from surgery. As a complete response to surgery in GH‐secreting macro‐adenomas can be difficult, first‐line therapy with octreotide LAR can be considered as a viable alternative for most patients with acromegaly, due to its low complication rate.