The acetate salt of a synthetic cyclic octapeptide analogue of somatostatin. Lanreotide binds to somatostatin receptors (SSTR), specifically SSTR-2 and also to SSTR-5 with a lesser affinity. However, compared to octreotide, this agent is less potent in inhibiting the release of growth hormone from the pituitary gland. Furthermore, lanreotide has an acute effect on decreasing circulating total and free insulin-like growth factor 1 (IGF-I). This agent is usually given as a prolonged-release microparticle or Autogel formulation for the treatment of acromegaly and to relieve the symptoms of neuroendocrine tumors.