From start to finish, CMC represents a lot of work by different departments, on different aspects that ultimately result in a robust process producing a drug of consistent quality.
The more of this work is done early, the less likely it is there will be delays because a batch unexpectedly fails. The more is postponed to a later phase, however, the quicker a drug can move into the clinic where it can be determined if there are signs of efficacy.
Balancing these two pressures, of increasing understanding early vs. failing early in the clinic without expending enormous resources, involves setting a strategy where the risks are identified and decisions are taken of when it is appropriate to take those risks. This will differ from project to project and company to company.
The CMC experts at 3D-PharmXchange have each done this multiple times on many projects and together with you will use their expertise to craft a risk strategy that is appropriate for the specifics of your drug, indication, and company.