Crystal engineers have found a way to change the solvated form of the non-steroidal anti-inflammatory drug celecoxib to improve oral availability.

Crystals of the NSAID marketed as the COX-2 selective anti-inflammatory drug (Cel-III) are not very soluble in water. Now, researchers in the US at TransForm Pharmaceuticals and Brandeis University have produced crystalline hydrates and propylene glycol solvates of the celecoxib sodium salt (Cel-Na) to see whether oral drug absorption might be improved by breaking up the hydrogen-bonding interactions present in the commercial product. The team found that the trihydrated form of the sodium salt is the most stable seen to date and has a much improved oral availability for a new product.

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• Celecoxib sodium salt: engineering crystal forms for performance,
  Julius F. Remenar, Mark D. Tawa, Matthew L. Peterson, Örn Almarsson, Magali B. Hickey, Bruce M. Foxman,
  CrystEngComm 2011.
  DOI: 10.1039/C0CE00475H