Impurity Profile & Justification

Regulators expect every reported and specified impurity to be characterized, qualified and justified — a control strategy without a clear justification narrative invites queries and delays. PharmExpert builds impurity profiles and the scientific justification that supports your specifications for drug substance and drug product.

We characterize and identify the impurity profile, distinguishing process-related impurities from degradation products, and establishing structures where needed. This profiling is the evidence base on which every downstream limit and argument rests.

Each impurity is then assessed against ICH qualification thresholds (Q3A/B) and, where relevant, for toxicological relevance with toxicology support. Proposed specifications are justified against those thresholds and against real batch data, so limits are neither arbitrarily tight nor indefensibly loose.

Finally we author the impurity sections and justification-of-specification documents in dossier-ready form, and support responses to the impurity-related questions agencies frequently raise. The outcome is a specification you can defend on the science — and a smoother path through review.