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# Guidance on Pharmaceutical Co-Crystals
- URL: https://www.fdaweb.com/guidance-on-pharmaceutical-co-crystals/
- Published: 2016-08-17T12:00:00.000Z
- Updated: 2026-09-14T21:25:07.000Z
- Author: David McFarland
- Tags: FDA Policy/General, #legacy-id-D5136543

*Federal Register* Notice: FDA is making available a draft guidance for industry entitled *Regulatory Classification of Pharmaceutical Co-Crystals*. It provides applicants planning to submit NDAs and ANDAs with information on the appropriate regulatory classification of pharmaceutical co-crystal solid-state forms. This guidance also provides 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. It revises the guidance for industry entitled Regulatory Classification of Pharmaceutical Co-Crystals issued in 4/2013\. To download this guidance, click [here.](http://www.fda.gov/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/UCM516813?ref=fdaweb.com) To view this notice, click [here.](https://www.gpo.gov/fdsys/pkg/FR-2016-08-17/pdf/2016-19596.pdf?ref=fdaweb.com)