
FDA Posts ICH Q4B Analytical Guidances
The US Food and Drug Administration has published a draft guidance, Q4B Regulatory Acceptance of Analytical Procedures and/or Acceptance Criteria (RAAPAC).
The US Food and Drug Administration (Rockville, MD,
At the same time, FDA published the first specific draft guidance under the RAAPAC procedure, Annex 1: Residue on Ignition/Sulphated Ash General Chapter Analytical Procedures and/or Acceptance Criteria (APAC) (
The guidance describes the reconciliation (via specification of sample size and a caveat on test-furnace calibration) of US Pharmacopeia, European Pharmacopoeia, and Japanese Pharmacopoeia testing procedures for residual ash, an index of the inorganic impurities in an organic sample.
The eight-page guidance and four-page annex were posted jointly by the Center for Drug Evaluation and Research and the Center for Biologics Evaluation and Research.




