A critical analysis of clinically available somatostatin analog formulations for therapy of acromegaly.
BACKGROUND
Short and long-acting somatostatin (SRIF) analogs are approved for clinical use in acromegaly. Recent analysis of the relative efficacy of octreotide LAR and lanreotide SR on the GH-IGF-I axis in acromegaly favored octreotide LAR in the secondary treatment of patients not preselected by SRIF responsiveness. A novel aqueous formulation of lanreotide, lanreotide Autogel (ATG), has recently been approved and is the predominant (and only in the United States) formulation of lanreotide used clinically.


OBJECTIVE
We performed a critical review of SRIF analog treatment to establish the relative efficacy of three clinically available SRIF analog preparations, octreotide LAR, lanreotide SR, and lanreotide ATG (Somatuline depot in the United States) in control of the GH-IGF-I axis in acromegaly.


METHODS
Data were drawn from MEDLINE and the bibliography of analyses of long-acting SRIF analogs.


METHODS
We reviewed the largest studies of sc octreotide, octreotide LAR, and lanreotide SR, all that included biochemical end-point data for lanreotide ATG, and studies that directly compared the efficacy of octreotide LAR and lanreotide SR.


RESULTS
Caveats considered included differences in baseline GH and IGF-I values, patient selection, and interassay and intraassay variability, confounding the analysis. Studies comparing patients treated contiguously with lanreotide SR and octreotide LAR are fraught with methodological problems, however, are suggestive of marginally greater efficacy in control of the GH-IGF-I axis for octreotide LAR. Lanreotide ATG shows noninferiority to lanreotide SR. Five small studies directly comparing octreotide LAR and lanreotide ATG suggest no significant differences between these preparations in control of biochemical end-points.


CONCLUSIONS
Lanreotide ATG and octreotide LAR are equivalent in the control of symptoms and biochemical markers in patients with acromegaly.
Murray
Robert D
RD
Department of Endocrinology, Leeds Teaching Hospitals National Health Service Trust, Leeds, UK.
Melmed
Shlomo
S
D000172:Acromegaly / Q000188:drug therapy*; D002626:Chemistry, Pharmaceutical; D003692:Delayed-Action Preparations; D006801:Humans; D015282:Octreotide / Q000008:administration & dosage / Q000627:therapeutic use*; D010456:Peptides, Cyclic / Q000008:administration & dosage / Q000627:therapeutic use*; D013004:Somatostatin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use
D003692:Delayed-Action Preparations; D010456:Peptides, Cyclic; C060347:lanreotide; D013004:Somatostatin; D015282:Octreotide