The United States Pharmacopeia publishes proposed revisions to USP-NF in the Pharmacopeial Forum, which appears bimonthly and carries a 90-day comment period that ends on the last day of a month. That cadence is the only reliable way to see a compendial change coming before it becomes official text, and 2026 has been a busy year for chapters that analytical and process-analytics groups actually have to live with.
Three issues frame the current position. PF 52(3) posted on 2 May 2026 and closed to comment on 2 August 2026. PF 52(4) posted on 1 July 2026 and closes on 30 September 2026. PF 52(5) posted on 1 September 2026 and runs to 30 November 2026.
For anyone tracking the analytical-methods chapters, the picture is split. The headline proposals in the current issues are packaging and container chapters. The chapters that govern method validation, instrument qualification, chemometrics and process analytics closed their windows earlier and are now working through the expert committee ballot stage, where the next visible event is official text rather than another draft.
Closing on 30 September
The proposal with the nearest deadline is a revision to General Chapter <659> Packaging and Storage Requirements, published in PF 52(4). USP proposes to redefine Controlled Room Temperature as 15-25 degrees C. The current compendial definition is 20-25 degrees C with permitted excursions between 15 and 30 degrees C. The lower bound moves; mean kinetic temperature is retained for evaluating short-term excursions above 25 degrees C. USP’s stated rationale is alignment with the Japanese Pharmacopoeia, Ph. Eur. and WHO definitions of room temperature, along with reduced HVAC energy demand.
This is a storage chapter rather than a method chapter, but it touches analytical operations directly. Stability protocols, reference standard storage conditions, sample retention areas and the qualification envelope of any instrument sitting in a controlled space are all written against the <659> definition. A change to the lower bound is not neutral for laboratories whose environmental monitoring alarms are configured at 20 degrees C.
Glass chapters: a compendial test moves to a spectrometer
PF 52(3) carried a substantial rework of the glass container chapters, and although the comment window has closed, the content is worth noting because of what it does to the test methods. General Chapter <660> Containers-Glass is proposed for retitling as “Glass Containers and Their Composition”. The draft introduces aluminosilicate and quartz glass alongside the existing types, replaces the Glass Grains Test with elemental composition by wavelength-dispersive X-ray fluorescence, deletes the Surface Etching Test, and adds an ICP-based determination of extractable arsenic. The companion informational chapter <1660> is proposed for expansion to cover glass manufacture, surface treatment and delamination risk assessment across four glass families. If adopted, the official date would be 1 August 2027.
Replacing a wet-chemical grains test with WDXRF is the kind of change that reallocates work between a QC laboratory and an instrument budget. Packaging groups that have never owned an X-ray fluorescence instrument would need one, or a contract laboratory arrangement, before the official date.
The analytical chapters are past comment, not past attention
Four chapters of direct interest to process analytics have moved through consultation in the past eighteen months and are now in revision workflow.
General Chapter <1225> was published in PF 51(6) with a proposed retitle from “Validation of Compendial Procedures” to “Validation of Analytical Procedures”, closing to comment on 31 January 2026. The draft reframes validation around fitness for purpose and the reportable result, brings in confidence, prediction and tolerance intervals for evaluating accuracy and precision together, and ties the chapter into the analytical procedure lifecycle described in <1220>. The stated aim is closer alignment with ICH Q2(R2) - the same convergence we tracked in our ICH Q14 implementation review.
General Chapter <1058> appeared in PF 51(2) with a proposed retitle to “Analytical Instrument and System Qualification” and closed on 31 May 2025. The draft folds the familiar DQ/IQ/OQ/PQ model into a three-stage lifecycle and adds sections on risk assessment, calibration, change control and roles.
General Chapter <1039> Chemometrics was reopened in PF 51(4), closing 30 September 2025. The draft reorganises the core section around unsupervised learning, supervised learning with categorical data and supervised learning with continuous data, adds subsections on data structures and signal preprocessing, and restructures the model section around a model lifecycle. That framing matters for anyone maintaining calibrations under GMP; the practical mechanics are the subject of our note on validating a chemometric model under GMP.
A proposed new chapter <1037> Process Analytical Technology-Theory and Practice was posted for feedback until 31 July 2025, accompanied by two stimuli articles covering theory of sampling in PAT and implementation of real-time release testing. Together with the Raman chapters <858> and <1858>, which we reviewed at their five-year mark, it would give process analytics a fuller compendial spine than it has had.
Two items outside the PF cycle
Separately, the Chemical Analysis Expert Committee issued a Notice of Intent to Revise for <621> Chromatography, cancelling the PF 49(6) proposal and publishing an amended version in PF 51(2) targeting an official date of 1 June 2026, with clarified System Sensitivity and Peak Symmetry sections. And USP published a General Chapter Prospectus dated 2 April 2026 for a new chapter on supercritical fluid chromatography, taking feedback on the intended outline until 28 May 2026. The chapter number has not been assigned.
The prospectus route is the earlier and cheaper place to influence a chapter, since it asks what the chapter should contain rather than whether a drafted method works. Groups that only monitor PF see chapters at the point where the scope is already fixed.