Analysis of the polymorph changes of a drug candidate.

Journal of pharmaceutical and biomedical analysis (2014-10-12)
P Láng, E Várkonyi, J Ulrich, P Szabó-Révész, Z Aigner
ABSTRACT

The effects of solvents, temperature and humidity on the stability of a former drug candidate obtained from Sanofi (Hungary) were examined by a slurry equilibration method, variable temperature and humidity X-ray powder diffractometry (VT/VH-XRPD) and differential scanning calorimetry (DSC). The VH-XRPD study showed that all 8 polymorphic forms of this material were stable in the interval 20-80 RH%. The VT-XRPD measurements indicated that all the polymorphs except Form II underwent changes in the range 30-200°C. The stable form was Form II, though Form IVb had almost the same stability. The investigation demonstrated that VT-XRPD is a very useful in situ method for relative stability studies.

MATERIALS
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Product Description

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