Polymorphic forms of naltrexone
This invention relates to the discovery of novel polymorphic forms of naltrexone, including solvates, hydrates, anhydrous and other crystalline forms and combinations thereof. These novel forms of naltrexone impart advantages in pharmaceutical formulations incorporating them, including sustained release, or long acting, formulations.
1. A polymorphic form of naltrexone acetonitrile solvate which is characterized by at least one of:
(a) the X-ray powder diffraction pattern of FIG. 1A ;
(b) the differential scanning calorimetry thermogram of FIG. 13A ; and
(c) the IR-ATR spectrum of FIG. 25A .
2. A pharmaceutical composition comprising the polymorphic form according to claim 1 and a pharmaceutically acceptable carrier.
3. A polymorphic form of naltrexone acetonitrile solvate which is characterized by at least one of:
(a) the X-ray powder diffraction pattern of FIG. 1B ;
(b) the differential scanning calorimetry thermogram of FIG. 13B ; and
(c) the IR-ATR spectrum of FIG. 25B .
4. A pharmaceutical composition comprising the polymorphic form according to claim 3 and a pharmaceutically acceptable carrier.