Where should chromatograms be provided for impurities?
A2: ICH Q3A identifies the chromatograms as part of the analytical validation studies. Therefore, relevant chromatograms should be included in 3.2.S.4.3. Q3: Where should nonclinical and clinical data supporting impurity levels be summarized? A3: The qualified level of each impurity with cross-reference to the supporting nonclinical/clinical studies should be included in 3.2.S.3.2. Q4: Should data on impurities reported in batch analyses be included in 3.2.S.3.2 or 3.2.S.4.4? A4: Data on observed impurities for relevant batches (e.g., clinical, nonclinical, stability) should be provided in 3.2.S.3.2. The data should be provided whether or not the impurity is included in the specification. This information can be cross-referenced to support other sections of the application as appropriate. S.4 Control of Drug Substance S.4.1 Specification Q1: If there are different specifications for a drug substance manufacturer and/or applicant, should they all be provided in 3.2.S.4.1? A1: When appro
