Background: Somatostatin analogues have been used successfully for the treatment of acromegaly but no randomized studies have compared the effects of lanreotide Autogel (LAN) and octreotide acetate long-acting repeatable (OCT).
Objective: To compare the effect of LAN and OCT for the treatment of acromegaly in a randomized study design.
Material and methods: Twelve acromegalic patients were included and 10 patients completed treatment with LAN or OCT for 6 months and were then switched to the opposite treatment modality for 6 months without a washout period in a randomized crossover design. GH and IGF-I profiles, clinical and biochemical evaluations were performed at 0, 4, 6, 10 and 12 months.
Results: After 6 months of treatment, five patients had GH levels < 0.38 microg/l during both therapies. The remaining patients had GH levels > 0.38 microg/l during both LAN and OCT treatment. Four patients had normalized IGF-I levels during both treatment regimes. Two patients on LAN and one on OCT had normalized IGF-I levels during one treatment and not during the other. In three patients, IGF-I levels were elevated during both therapies. Four patients developed palpable nodules, two patients on LAN and two patients on OCT. Gastrointestinal complaints were seen in three patients during both therapies, in three patients only during LAN, and in one patient only during OCT. Two patients were withdrawn from the study because of serious adverse effects during LAN. After the study period, four patients preferred LAN and six patients preferred OCT treatment.
Conclusion: The effects of LAN and OCT therapy on GH and IGF-I levels were comparable, but 3/10 patients had different treatment efficacies and 6/10 had different side-effect profiles during the LAN and OCT treatment. These results indicate that a change from LAN to OCT or vice versa may be beneficial in some patients with treatment failure or side-effects.