Stability Testing During Development of Nanopharmaceuticals

Background: Stability testing is key to assurance of quality of pharmaceuticals. All types of conventional and modified formulations, including nanopharmaceuticals, need to be subjected to extensive stability study program. Objective: To highlight the role of stability testing; nature of studies in different phases of drug and product development; discuss peculiarities of nanopharmaceuticals in difference to conventional and modified release products and outline differences in stability testing protocols. Method: A critical review was done of stability testing protocols employed in published reports during the development of nanopharmaceuticals. Results: The reported investigations rightly focused on the stability of carrier materials and changes in physical characteristics of formulations, but an important aspect missed out was the development of stabilityindicating analytical methods, without which it is difficult to determine chemical change in the drug with time and monitor formation of degradation products. Also, stability studies were conducted at very variable storage conditions. Conclusion: Stability testing of developmental nanopharmaceuticals must be done extensively, and systematically. It has to focus on functionality, integrity, size of particulates, carrier material stability, drug stability, degradation products, etc. It shall be ensured that the selected stability storage conditions are relevant for the specific product and studies are done in intended market packs.