Current Approaches for in vitro Drug Release Study of Long Acting Parenteral Formulations

Long acting parenteral formulations are preferred over conventional formulations for the treatment of chronic diseases. Prevalence of such diseases provoked the interest of researchers and pharmaceutical industries in the development of long acting parenteral formulations. The regulatory guidelines and pharmacopoeia have remained silent on dissolution methods for long acting parenteral formulations due to their diverse nature. The lack of compendial method for dissolution testing increases the duration of approval process for long acting parenteral formulations. This article reviews various dissolution methods used to study in vitro drug release profile of long acting parenteral formulations. Compendial as well as noncompendial methods, such as- rotating dialysis cell, dialysis tube, rotating bottle, shaking flask, single drop, inverted cup and incubation, are used by researchers for drug release profile of long acting parenteral formulations. This review article also highlights the advantages and disadvantages of reported dissolution methods along with the suitability of these methods for particular type of long acting formulation. The compiled work will help the researchers in designing the biorelevant dissolution method and expedite the development of long acting parenteral formulations. Keywords: Dissolution apparatus, injectable, in vitro models, long acting formulations, parenteral.