The stability of vaccines is of great interest industries and government institutions. Accelerated stability studies are designed to determine the rate of vaccine degradation over time as a result of exposure to temperatures higher than those recommended for product storage. However, commonly applied stability predictions based on application of zero- or first order kinetics are very often too simplified for description of the degradation of biological products, which frequently undergo complex and multistep degradation reactions. We used an advanced kinetic approach mixing with statistical analysis to fit the forced degradation data (ELISA, NTA … ) by computed kinetic parameters, and finally, to predict valuable the long term stability of vaccine. The modeling approach is based on the selection of the most appropriate kinetic equations which fit the degradation rate of compounds subjected to elevated temperatures, accelerating the rate of the reaction.

Establishing product stability is critical for pharmaceuticals. We used a modeling approach to predict the thermal stability of a fully-liquid quadrivalent meningococcal (serogroups A, C, W, Y) conjugate vaccine (MenACYW-TT; MenQuadfi®) at potential transportation and storage temperatures. Vaccine degradation was determined by measuring the rate of hydrolysis through an increase of free polysaccharide (de-conjugated or unconjugated polysaccharide) content during six months storage at 25°C, 45°C and 56°C. A procedure combining advanced kinetics and statistics was used to screen and compare kinetic models describing observed free polysaccharide increase as a function of time and temperature for each serogroup.

The main challenge for the formulation of biologically derived products is to control the rate of degradation of their constituents to ensure an acceptable lifetime during storage and transport around the world [1-3]. The concept of stability of biological compounds (proteins, viruses, bacteria) is complex to understand, involving theoretically, concepts of both thermodynamics and advanced kinetics. one way of estimating protein stability is to study the denaturation when a protein is subjected to chemical stress (denaturing agents, pH) or physical stress (temperature, pressure…, etc.).