USP seeks early Input on new NMR Method

USP has announced a General Chapter Prospectus for a proposed new chapter <319> Nuclear Magnetic Resonance Spectroscopy Block Length Determination for Lactide-Glycolide Polymers. The notice was posted on 31 October 2025, and USP is seeking early input from stakeholders until 30 November 2025, ahead of an anticipated proposal in PF 52(2) (March–April 2026).

Lactide-glycolide (PLG) and lactic acid-glycolic acid (PLGA) polymers are widely used as excipients in extended-release drug products and certain medical devices. However, due to their complex structure and variability, standardized analytical methods remain limited. This has often created challenges for manufacturers, particularly in the development and regulatory approval of generic products containing PLG/PLGA.

USP has previously introduced stand-alone chapters <315> and <316> to support improved characterization (NMR for number-average molecular weight and SEC for molecular weight distribution). The proposed new chapter <319> would extend this approach by providing a standardized NMR procedure to determine block length, a parameter considered critical to polymer performance.