1. International Conference on the Harmonization of the Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) Q3A(R): ‘Impurities in New Drug Substances’ (Revised Guideline) (1999).
2. Fed. Register 65 (140) (2000) 45085–45090.
3. Food and Drug Administration, Center for Drug Evaluation and Research (CDER) Draft Guidance, ‘NDAs: Impurities in Drug Substances,’ (issued December 1998).
4. Food and Drug Administration, Center for Drug Evaluation and Research (CDER) Draft Guidance, ‘ANDAs: Impurities in Drug Substances,’ (issued June 1998).
5. Food and Drug Administration, Guidance for Industry: ‘Manufacture, Processing, or Holding of Active Pharmaceutical Ingredients,’ (issued September 1996).