Lessons Learned through Failure in Pharmaceutical Process Development

Failures are routine in research laboratories, but in pharmaceutical process development and manufacturing they can be amplified by scale, equipment, operating windows, raw-material variability, and human intervention—directly affecting quality, supply, cost, and EHS. Turning such events into transferable knowledge requires capturing not only what happened, but why it happened, how it was contained, and how prevention was implemented. This article outlines two representative process chemistry failures and the lessons derived from them: (1) an unexpected loss of performance in a diastereomeric salt resolution during CMO manufacturing, ultimately linked to solid-state behavior and resolved through robustness-oriented crystallization redesign; and (2) a Suzuki-Miyaura coupling campaign in which conversion and yield were acceptable, yet residual palladium increased, highlighting the impact of plant-specific heat-transfer conditions and oxygen-management levels during workup.