How early should you engage a CDMO?

Engaging a CDMO early helps clarify technical requirements and risks, but CMC decisions should not be locked in before clinical and nonclinical evidence is in place. A company working on a poorly soluble API produced an engineering batch with a solubility-enhancement approach before PK and toxicology studies were completed, then had to redo the work, delaying its IND filing and clinical trial start. Another program took a phase-appropriate strategy, using fit-for-purpose clinical supply to support the IND filing and advancing process and scale-up development based on the data.