Efficacy and safety of the new 60-mg formulation of the long-acting somatostatin analog lanreotide in the treatment of acromegaly

Recently, a new slow-release (SR) formulation of lanreotide (LAN) comprising 60 mg of the drug incorporated in microspheres of biodegradable polymers (SR-LAN 60) has become available. The aim of our study was to assess the effectiveness of SR-LAN 60, administered every 21 to 28 days, as well as its tolerability in the long-term treatment of acromegalic patients treated with SR-LAN 30. Twenty patients with acromegaly (10 males and 10 females) were enrolled in this open study. Thirteen patients had undergone surgery, but with incomplete resection of the pituitary tumor. All patients, treated with intramuscular (IM) SR-LAN 30 injections every 10 days for 12 to 24 months, started SR-LAN 60 (Ipsen-Beaufour, Milan, Italy) administration 10 days after the last injection of SR-LAN 30. Growth hormone (GH) levels were determined on the day of the first injection of SR-LAN 60, and 10, 20, and 30 days after. According to the GH levels reached on day 30, patients received SR-LAN 60 every 28 days if GH levels were below 2.5 mug/L (group A) and every 21 days if GH levels were above 2.5 mug/L (group 13). In group A, after the 8th month, SR-LAN 60 treatment resulted in well-controlled GH levels in 9 of 10 patients in comparison to SR-LAN 30 treatment every 10 days (6 of 10 patients). Normal age-adjusted insulin-like growth factor-I (IGF-I) levels were achieved in 4 of 10 patients, as in treatment with SR-LAN 30. In group B, SR-LAN 60 treatment resulted in well-controlled GH levels in 4 of 10 patients, as in treatment with SR-LAN 30 every 10 days. Normal age-adjusted IGF-I levels were achieved in 3 of 10 patients after SR-LAN 60 in comparison to SR-LAN 30 treatment every 10 days (1 of 10 patients). During SR-LAN 60 therapy, an improvement was also observed in signs and symptoms of active acromegaly and no relevant side effects were detected. In conclusion, this study shows that SR-LAN 60 treatment is able to induce a good control of circulating GH and IGF-I levels in most acromegalic patients. The first injections of SR-LAN 60 are very helpful in predicting the optimal long-term injection frequency. Patients on SR-LAN 30 can be safely and effectively shifted to SR-LAN 60. Copyright (C) 2002 by W.B. Saunders Company.