Efficacy of lanreotide Autogel® administered every 4–8 weeks in patients with acromegaly previously responsive to lanreotide microparticles 30 mg: a phase III trial

OBJECTIVE AND DESIGN: Depot somatostatin analogues are well accepted as either adjuvant or primary therapy for acromegaly, and their long dosage intervals facilitate adherence to treatment. Our objective was to evaluate whether lanreotide Autogel® 120 mg, every 4–8 weeks, was as effective in controlling acromegaly as lanreotide microparticles 30 mg, every 1–2 weeks. PATIENTS DESIGN AND MEASUREMENTS: Patients who had used lanreotide microparticles 30 mg, ≥ 2 months prestudy, and had responded to treatment were recruited to this open, prospective, multicentre phase III trial. Three to five injections of lanreotide Autogel® 120 mg were administered. Lanreotide Autogel® 120 mg was injected every 4, 6 or 8 weeks in patients previously receiving lanreotide microparticles every 7, 10 or 14 days, respectively. GH and insulin-like growth factor (IGF)-1 levels were assessed one dosing interval after the final injections. RESULTS: Ninety-eight patients were enrolled and 93 completed. Steady-state GH concentrations demonstrated similar efficacy between the formulations (upper 95% confidence interval of the quotient, 77·7%). Mean (SE) GH levels were lower with lanreotide Autogel® than with lanreotide microparticles (3·8 (0·5) vs 4·3 (0·5) ng/ml; P < 0·001). GH levels < 2·5 ng/ml were observed in 54% and 46% of patients; 40% and 35% having GH < 2·5 ng/ml and normalized IGF-1 with lanreotide Autogel® and microparticles, respectively. Symptoms were controlled better with lanreotide Autogel® and treatment was well accepted. CONCLUSIONS: Lanreotide Autogel® 120 mg every 4–8 weeks, is at least as effective and as well tolerated in acromegaly as lanreotide microparticles 30 mg injected every 7–14 days.