Pharmaceutical designer crystals a reality?
Overall, the examples described above demonstrate that every advantage must be sought to aid the design of an appropriate crystalline form of an API. Thus, unsurprisingly, pharmaceutical co-crystals are gradually becoming an integrated part of the solid form screening activities of pharmaceutical companies,13 as exemplified by the decision tree presented in Figure 2. Finally, it should be pointed out that although bioavailability studies involving pharmaceutical co-crystals are still in their infancy, the case studies reported to date show a great promise with respect to the bioavailability enhancement of poorly soluble APIs.14–17 More importantly, these studies have demonstrated that even the co-crystals that tend to disso
Boosting pipelines and patent lifecycles
Patents have always been an imperative tool for the pharmaceutical industry so it is not surprising that intricate patent litigations are among the key issues that have triggered the shift of concerns towards material properties of APIs. Nowadays, the need of thorough investigation and optimisation of physicochemical and material properties for in vivo performance, reliable manufacture and the protection of intellectual property is well recognised in the pharmaceutical arena.
In this context, pharmaceutical co-crystals deserve special attention. Because of a large number of potential co-formers available, co-crystals represent a broad patent space and provide enormous opportunities for companies to boost their pipelines, as well as to manage patents throughout their lifecycle.
Co-crystals are rapidly emerging in the pharmaceutical arena, especially as a means of enhancing the physicochemical profiles of existing APIs. The uniqueness of pharmaceutical co-crystals as a solid state form is attributable to their susceptibility to supramolecular design. This implies that the functional properties of APIs — including solubility, physical stability and mechanical properties — can potentially be built-in during the co-crystal design. Furthermore, pharmaceutical co-crystals offer an opportunity for companies to significantly expand their intellectual property portfolios. From this perspective, the coming years are thought to be critical for bringing boost products containing pharmaceutical co-crystals to the market.
The authors thank the Finnish Cultural Foundation and the Academy of Finland for financial support.
Inna Miroshnyk is Senior Scientist in the Pharmaceutical Materials Research Group, Division of Pharmaceutical Technology, Faculty of Pharmacy, University of Helsinki (Finland).
Sabiruddin Mirza is Senior Scientist in the Drug Delivery and Nanotechnology Group, Centre for Drug Research, Faculty of Pharmacy, University of Helsinki (Finland).Tel. +358 9 191 59 582 firstname.lastname@example.org
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