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Physical stabilization of low-molecular-weight amorphous drugs in the solid state: a material science approach

    Sheng Qi

    School of Pharmacy, University of East Anglia, Norwich, Norfolk NR4 7TJ, UK

    ,
    William J McAuley

    Department of Pharmacy, School of Life & Medical Sciences, University of Hertfordshire, Hatfield AL10 9AB, UK

    ,
    Ziyi Yang

    School of Pharmacy, University College London, London, 29–39 Brunswick Square, London WC1N 1AX, UK

    &
    Pratchaya Tipduangta

    School of Pharmacy, University of East Anglia, Norwich, Norfolk NR4 7TJ, UK

    Published Online:https://doi.org/10.4155/tde.14.39

    Use of the amorphous state is considered to be one of the most effective approaches for improving the dissolution and subsequent oral bioavailability of poorly water-soluble drugs. However as the amorphous state has much higher physical instability in comparison with its crystalline counterpart, stabilization of amorphous drugs in a solid-dosage form presents a major challenge to formulators. The currently used approaches for stabilizing amorphous drug are discussed in this article with respect to their preparation, mechanism of stabilization and limitations. In order to realize the potential of amorphous formulations, significant efforts are required to enable the prediction of formulation performance. This will facilitate the development of computational tools that can inform a rapid and rational formulation development process for amorphous drugs.

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