ICH Q1 guideline on stability testing of drug substances and drug products

This guideline outlines the stability data expectations for drug substances and drug products. The purpose of stability testing is to provide evidence on how the quality of a drug substance or drug product varies with time under the influence of a variety of environmental and physical factors such as temperature, humidity, light, or agitation.

This guideline provides comprehensive guidance to establish stability for all molecule types within its scope and includes recommendations on how science- and risk-based principles may be applied. It is applicable to marketed drug products, including those associated with registration and lifecycle/post-approval changes and, when applicable, master files.

ICH Q1 is a consolidated revision that supersedes ICH Q1A-F and Q5C guidelines and provides additional guidance on principles relating to stability.

Current version

Draft ICH Q1 guideline on stability testing of drug substances and drug products - Step 2b

Draft: consultation closed Consultation dates: 30/04/2025 to 30/07/2025 Reference Number: EMA/CHMP/ICH/130561/2025 Summary:

Comments should be provided using this template. The completed comments form should be sent to [e-mail] 

Overview of comments received on ICH Q1 Guideline on stability testing

Reference Number: EMA/240075/2025