FDA Regulatory Implications for Co-crystals and recent Co-crystal Patents

  • Samuel Rigilin Department of Pharmaceutics, Srinivas College of Pharmacy, Valachil, Mangalore, Karnataka, India – 574143
  • Krishnananda Kamath Kunjal
  • Abdul Raheem Thayyil
  • Ramakrishna Shabaraya


One of the most crucial stages in the creation of a medicinal product is the characterization of an Active Pharmaceutical Ingredient (API). Unfortunately, not all APIs have the ideal characteristics for medicinal usage. Many freshly discovered active compounds, for example, have low solubility. However, various methods have been developed to change and improve an API's features to get desired physicochemical properties, which is an important tool in formulation development. The production of salt derivatives is a common technique for increasing the solubility of an active chemical. This method, however, has limits because not every API has the qualities to be transformed into a salt. In recent years, a novel engineering approach for creating new API forms with desirable features has been established. The development of pharmaceutical co-crystals is the result of these efforts which allow pharmaceutical companies to customise existing APIs or create new ones with specific properties. Aside from the scientific hurdles that come with developing a pharmaceutical, manufacturers are also faced with regulatory regulations that must be met in order to get approval and access the market. As pharmaceutical co-crystals are a relatively new API, little regulatory guidance for co-crystals has been developed for one of the world's largest pharmaceutical market the United States of America (USA).

This article will look at what regulatory standards must be met in order to employ pharmaceutical co-crystals in generic medications intended for use in the United States. It will also go over which data should be included in the common technical document to justify its existence. In addition to, a brief information of various patents on co-crystals have also been included for better knowledge of the reader.

Keywords: Pharmaceutical co-crystals, Coformer, Regulatory guidelines, Common technical document, FDA, Patent


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How to Cite
Samuel Rigilin, K. K. Kunjal, A. R. Thayyil, and R. Shabaraya. “FDA Regulatory Implications for Co-Crystals and Recent Co-Crystal Patents”. International Journal of Drug Regulatory Affairs, Vol. 10, no. 3, Sept. 2022, pp. 10-18, doi:10.22270/ijdra.v10i3.541.