A Kinetics-Based Approach for the Assignment of Reactivity Purge Factors

The control of mutagenic impurities is of crucial interest to pharmaceutical companies and regulatory agencies alike. One risk-based methodology to assess the likelihood of impurity carryover to drug substance entails evaluation of the physicochemical properties of the entity against the parameters of the chemical process to which it is exposed. This article details a simple experimental approach that utilizes kinetic analyses to facilitate the assignment of reactivity purge factors. These reactivity purge factors are important values in the semiquantitative risk assessment for impurity carryover to drug substance.