Patent ID: 8916610

Claim:
A crystalline form of a fumaric acid addition salt of nortriptyline-4-aminobutyrate, characterized by at least one of: (a) an X-Ray Powder Diffraction (XRPD) pattern exhibiting at least four peaks selected from the group of peaks having a refraction angle (2θ) of 3.8; 7.4; 10.2; 12.2; 13.0; 14.5; 15.2; 16.7; 18.6; 18.8; 19.2; 20.0; 20.6; 21.0; 21.7; 22.0; 23.0; 24.5; 24.8; 25.3; 26.1; 27.5; 31.0; and 37.5 degrees; (b) an infrared spectrum exhibiting at least three absorption peaks selected from the group consisting of absorption peaks at 2926, 1701, 1652, 1632, 1485, 948, 755, and 648 cm −1 ; and (c) a Differential Scanning Calorimetry (DSC) exhibiting an endothermic peak maximum that ranges from 155° C. to 160° C.