WuXi AppTec Explores CDMO Shifts in Oligonucleotide Delivery

WuXi AppTec's analysis of extrahepatic oligonucleotide delivery signals a meaningful shift in CDMO manufacturing scope: programs targeting muscle, the central nervous system, lung, immune cells, and tumors require conjugate chemistries, purification strategies, and bioanalytical frameworks that differ substantially from the liver-directed model that has defined the field to date.

The liver established the template. GalNAc conjugation exploits high asialoglycoprotein receptor (ASGPR) expression on hepatocytes, enabling receptor-mediated endocytosis following subcutaneous administration. That mechanism produced a chemically defined, carrier-free construct reproducible across conjugate synthesis, purification, analytical characterization, and formulation, a model that has supported multiple approved siRNA medicines. Outside the liver, no equivalent receptor-ligand pair offers comparable universality.

For muscle, antibody or peptide conjugates targeting transferrin receptor 1 (TfR1) represent one emerging route, given TfR1 expression on skeletal and cardiac muscle cells and its capacity for internalization. CNS, lung, and immune-cell programs each present distinct receptor biology, cellular uptake kinetics, and intracellular trafficking profiles, driving developers toward tissue-specific strategies rather than a platform approach. Targeted nanoparticles are under evaluation alongside conjugate formats, each carrying different implications for impurity control, dose, safety margins, and bioanalytical method development.

Yu Lu, Senior Vice President of WuXi TIDES, framed the manufacturing consequence directly: connecting targeting biology, molecular design, analytics, and scalable manufacturing will determine which extrahepatic programs advance from preclinical science to approved therapeutics. For QA directors and process development leads, that connection translates into earlier decisions on conjugate synthesis routes, purification train design, and the bioanalytical strategy needed to characterize novel impurity profiles at non-liver tissues.

Delivery strategy, in this context, is not a late-stage formulation question. Choices made at the molecular design stage propagate through biodistribution studies, GMP process validation, and the analytical control strategy submitted to regulators, compressing the window in which manufacturing and quality functions can course-correct without program-level cost.

As extrahepatic programs move from preclinical into IND-enabling studies, the manufacturing and quality infrastructure built around GalNAc-siRNA will require targeted expansion rather than direct transfer, with each new tissue type demanding its own validated bioanalytical and process control framework.

Source: WuXi AppTec via GlobeNewswire Industry News on Pharmaceuticals, 3 September 2026.