Pharmaceutical Co-Crystal Classification Guidance
FDA has issued a guidance, Regulatory Classification of Pharmaceutical Co-Crystals, to give applicants planning to submit NDAs and ANDAs information on the appropriate regulatory classification of pharmaceutical co-crystal forms. The guidance includes information about the data that applicants should submit to support the appropriate classification of a co-crystal, as well as the regulatory implications of the classification.
FDA says the recommendations in the document apply to materials that it has not previously evaluated and determined to be pharmaceutical co-crystals. The recommendations do not apply to materials that the agency has previously designated as salts, complexes, or other non-crystalline forms.