FDA Publishes Guidance on Classification of Co-Crystals

On Feb. 14, 2018, FDA published guidance for sponsors submitting new drug applications (NDAs) and abbreviated new drug applications (ANDA) regarding the regulatory classification of co-crystal solid-state forms not previously evaluated by the agency and determined to be pharmaceutical co-crystals. The guidance also discusses which data sponsors should submit to support the classification.

According to the guidance, NDA and ANDA applicants should provide evidence to demonstrate that the API and coformers are present in the unit cell, that the component API and coformer co-exist in the co-crystal which interact nonionically, and that substantial dissociation of the API from its co-crystal form occurs before reaching the site of pharmacological activity. “The type and extent of characterization and release testing performed on the co-crystal should be sufficient to ensure the identity, strength, quality, and purity of the API(s),” the document states.