December 22, 2025

Avoiding Common Pitfalls in API Regulatory Starting Material (RSM) Justification 

Regulatory starting material (RSM) selection and justification can make or break your API CMC strategy. Regulatory authorities such as the FDA and EMA carefully scrutinize RSM designations, and inadequate justification is a frequent cause of information requests, delayed approvals, or even refusal to file.  Selecting the wrong starting material—or failing to justify it properly—can trigger extensive […]