Early CMC can sharpen drug candidate selection

WuXi AppTec’s published case studies show how early chemistry, manufacturing and controls work can help drug teams judge not just whether a molecule works, but whether it can be synthesized, formulated and scaled. The examples point to a practical hiring test for CROs and CDMOs: whether discovery, process and analytical experts can jointly turn liabilities into decision-making before a candidate is locked in.

Why it matters: - Early chemistry, manufacturing and controls work can expose developability and manufacturability problems before a candidate is selected. - Drug teams can use those findings to decide what to optimize, what to de-risk, and whether a molecule has a realistic path to clinical supply. - For CROs and CDMOs, early CMC integration is a signal of whether discovery chemistry, process chemistry, formulation and analytical work are coordinated enough to support later development.

What happened: - WuXi AppTec published two case studies that illustrate how early CMC questions can shape candidate decisions and downstream development. - The cyclic-peptide case study tied candidate selection to developability and then moved the program into process scale-up. - The targeted protein degrader case study showed how process and formulation teams handled development liabilities that discovery teams can assess earlier. - The article uses those cases to frame what drug discovery teams should look for when evaluating a CRO/CDMO.

The details: - Early CMC assessment should test whether a biologically promising molecule has a practical path to synthesis, formulation, analytical control and scale-up. - Discovery teams often optimize potency and selectivity first, but changes that improve one property can create a manufacturing or analytical burden elsewhere. - Oligonucleotides, targeted protein degraders and conjugated therapeutics are especially exposed to these tradeoffs because chemistry and biology are tightly linked. - For peptide-conjugated oligonucleotides, chemically modified nucleotides and unnatural amino acids can become sourcing bottlenecks as a candidate advances. - The core question is not only whether a molecule works in assay or model systems, but whether it can be made and tested reliably at clinical scale. - Teams evaluating a CRO/CDMO should ask how the provider handles synthetic complexity and scale-up risk. - Teams should also ask how solubility, stability and delivery requirements shape formulation strategy. - Analytical control is another key question, including how characterization and testing needs evolve as the molecule advances. - A good early CMC process should connect chemistry, formulation and analytical findings to candidate optimization and selection.

Between the lines: - The cyclic-peptide case presents developability as something that can be considered alongside potency and stability, not only after selection. - More than 1,700 cyclic peptides were synthesized and screened in that program, followed by hit validation and lead optimization. - Within about one year, WuXi AppTec selected a preclinical candidate based on potency, stability and developability. - The discovery chemistry team then delivered eight consecutive batches of about 50 g each, with a lead time of two to three weeks per batch. - The transition from discovery chemistry to API development and analytical teams took one business day. - The process then scaled from about 50 g to a 1 kg demonstration batch and a 6 kg batch for GLP studies within six months. - That sequence suggests one value of early CMC: continuity from candidate selection into process development without a long handoff. - The targeted protein degrader case shows the other side of the same lesson: hard development problems can be visible earlier if teams ask the right questions. - The original synthetic route used 24 steps and had an overall yield of 0.3%. - The candidate’s high molecular weight and poor solubility contributed to oral bioavailability of 0.9%. - Several palladium-catalyzed steps added process and cost pressure. - WuXi STA’s process chemistry, biocatalysis and crystallization teams reduced the route to 16 steps and replaced palladium catalysts with biocatalysts in two steps. - Formulation scientists selected spray-dried dispersion to address poor solubility, improving oral bioavailability by about 30-fold. - Coordinated process and formulation work delivered material for IND-enabling studies and clinical trial formulations within 12 months. - The case does not prove that early CMC prevented redesign, but it does show which liabilities can be spotted before candidate selection.

What's next: - Drug teams assessing CROs and CDMOs are likely to put more weight on whether specialists can translate development concerns into concrete plans. - The practical test is whether a provider can connect candidate evaluation to the next stage of work with clear priorities and responsibilities. - WuXi AppTec’s examples give teams reference points for those conversations, especially around synthesis, formulation, analytical control and scale-up.

The bottom line: - Early CMC is less about slowing discovery than about making candidate selection more realistic.