Formulation and in vitro / in vivo Evaluation of Novel Biodegradable Microspheres for Treatment of Hormone Responsive Cancers

Objectives: The present work relates with developing long acting controlled release poly(DL-lactide-co-glycolic acid) (PLGA) microspheres of Goserelin acetate for treatment of breast and prostate cancer. Methods: Microspheres were prepared by using biodegradable polymers PLGA 50:50 and PLGA 75:25 employing modified emulsification method by using static mixer. Evaluate the effect of process and formulation variables on the characteristics of microspheres were studied. Particle size distribution, surface morphology, encapsulation efficiency, in vitro drug release and in vivo drug release profile in Wistar rats were investigated. Results: Preparative variables such as concentrations of stabilizer, drug-polymer ratio, stirring rate and ratio of internal to external phases were found to be important factors for the preparation of Goserelin acetate loaded PLGA microspheres. These changes were also reflect in vitro and in vivo drug release profiles. The result indicated that the morphology of Goserelin acetate PLGA microspheres presented as spherical shape with smooth surface, homogenous drug distribution and the particle size distributed from 88.11 to 116.78 μm. In vitro and in vivo release profile showed controlled initial burst release followed by one month sustained release profile of the Goserelin acetate loaded PLGA microspheres. Conclusion: The process and formulation variables could be effectively modified to achieve the desired characteristics and one month sustained release of Goserelin acetate loaded biodegradable polymeric microspheres showed potential for treatment of hormone responsive cancers.