Formulation and Evaluation of Octreotide Acetate Loaded Plga Microspheres

Objective: The objective of the present work was to formulate and evaluate controlled release Octreotide acetate microspheres for subcutaneous administration for treating symptoms associated with metastatic carcinoid and vasoactive intestinal peptide tumors (VIPsecreting tumors) and acromegaly effectively and also to improve patient compliance with fewer side effects. Octreotide is a long acting cyclic octapeptide with pharmacologic properties mimicking those of the natural hormone somatostatin. It inhibits growth hormone, glucagon, and leutinizing hormone response to Gonadotropin releasing hormone, serotonin gastrin, vasoactive intestinal peptide, motilin and pancreatic polypeptide. Method: Different formulations were prepared by following solvent evaporation technique (double emulsion) using biodegradable poly (Lactide-coGlycolide) acid and evaluated for percentage yield, entrapment efficiency, surface morphology (SEM), particle size analysis, in-vitro drug release and stability studies. Results: The prepared microspheres were white, free flowing and spherical in shape. The mean Particle size of the microspheres was found in the range of 26 to 206μm. The drug-loaded microspheres showed 70-86% of entrapment and release was extended up to 6 to 8 h releasing 93% of the total drug from the microspheres. The infrared spectra showed stable character of octreotide in the drug-loaded microspheres and revealed the absence of drug-polymer interactions. Scanning electron microscopy study revealed that the microspheres were spherical and porous in nature. Conclusion: The octreotide is uniformly distributed within the microspheres which are made of a biodegradable D,L-lactic and glycolic acids copolymer. The optimized formulations of Octreotide acetate microspheres with controlled release were attempted for a release upto atleast one month.