Dynamics can render an active pharmaceutical ingredient (API) difficult to crystallise, making the development of a commercially relevant process challenging, while also complicating the process of structural characterisation. A collaboration between academia (University of Warwick) and industry (AstraZeneca) with funding from Innovate UK published in CrystEngComm reports an instance of taming the dynamics in Efavirenz, an anti-HIV pharmaceutical, using cocrystallisation. The study provides the first systematic investigation on how the dynamics are influenced by the addition of a coformer.  X-ray crystallography, DFT calculations, and solid-state NMR results support that the Efavirenz cocrystals have remarkably less dynamics than pure Efavirenz

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