efficacy of a slow-release formulation of lanreotide (Autogel) 120 mg in patients with acromegaly previously treated with octreotide long acting release (LAR): an open, multicentre longitudinal study

Objective Lanreotide Autogel® 120 mg (ATG120; Ipsen S.p.A, Milan, Italy) is a high-dose, sustained-release aqueous gel formulation, supplied in a prefilled syringe and given by deep subcutaneous injection. The aim of this study was to compare efficacy and tolerability of ATG120 given every 4–8 weeks with those of octreotide LAR (o-LAR) given every 4 weeks. Design patients and intervention A phase III multicentre Italian open clinical study of 23 acromegalic patients (15 female, 8 male). All patients had received o-LAR for 6–18 months and, after 3 months wash out, ATG120 was given every 6 weeks for a total of four injections (Period 1). Then the interval between ATG120 injections was adjusted according to three different schemes: every 4, 6 or 8 weeks depending on GH levels (GH > 2·5 μ g/l; 1 < GH ≤ 2·5 μ g/l; GH ≤ 1 μ g/l, respectively). ATG120 was given for a further two to three doses, with a final assessment (Period 2) at Week 34, 36 or 42. Measurements Hormonal (GH and IGF-I) and clinical efficacy and tolerability. Results ATG120 induced a significant GH decrease from 9·9 ± 11·3 at baseline (Visit 1) to 3·5 ± 5·7 at the end of Period 1 ( P < 0·01) and to 3·8 ± 5·7 μ g/l at the final visit ( P < 0·01). IGF-I also decreased from 544 ± 312 at baseline (Visit 1) to 318 ± 181 at Period 1 and to 356 ± 187 μ g/l at the final visit (both P < 0·05 vs. baseline). The frequency of ATG120 administrations was adjusted to every 4 weeks in 12 patients, every 6 weeks in 4 patients and every 8 weeks in 6 patients; 1 patient withdrew before the dose adjustment. Serum GH and IGF-I achieved at the end of Period 1 and Period 2 were similar to those reached with o-LAR. The number of patients who achieved GH < 2·5 μ g/l was comparable between o-LAR (43%) and ATG120 at Period 1 (48%) and at Period 2 (62%). Normal IGF-I levels were recorded in 8 patients during o-LAR (35%), 11 during ATG Period 1 (48%) and 10 at the final visit (43%). Last, 4 patients showed a better response to ATG120 and 2 to o-LAR.Conclusions Lanreotide Autogel 120 mg is an effective and welltolerated therapy for acromegaly. In approximately half of patients ATG120 may be administered every 6–8 weeks, instead of every 4 weeks, without lost of efficacy