A Review on Long Acting PLGA Based in Situ Forming Microparticles Formulation for a Novel Drug Delivery System

Pharmaceutical research has recently been focusing on new inject able drug delivery systems which provide long therapeutic effects, minimum initial burst effect, reduced side effects, and involving simplified production stages and facilitate application process. In situ forming micro particle (ISM) systems, one of the latest approaches in this field, offer a new encapsulation technique and meet the objectives state above. Factors such as the carrier use to form the multiparticles, amount and type of drug and the vehicle type can be taken as the main performance criteria for these systems. Ongoing studies have shown that this new multiparticulate drug delivery system is suitable for achieving new implant delivery system with low risk of dose-dumping, capable of being modulated to exhibit varying release patterns, reproducible, easily applicable and well-tolerable. A novel in situ method for the preparation of inject able biodegradable poly(lactide-co-glycolide) (PLGA) micro particle for the controlled delivery of drug using DMSO as solvent. A stable dispersion of PLGA microglobules (`premicroparticles' or `embryonic micro particles') in a vehicle mixture usually biocompatible oils on injection comes in contact with water from aqueous buffer or physiological fluid, thereby hardening the microglobules into solid matrix type micro particles entrapping the drug (in situ forming micro particles). The myotoxicity was assessed by measuring the cumulative release of creatine kinase (CK) to evaluate the muscle damage caused by this formulation. CK release will be significant lower decreased with a lower polymer phase: oil phase ratio. The vivo studies confirmed the in vitro data and showed good muscle compatibility of the ISM-system.