Solid state forms of ivosidenib

A crystalline Form of Ivosidenib monohydrate, which is characterized by data selected from one or more of the following:

• i) an XRPD pattern having peaks at 10.3, 12.4, 17.8, 20.0, 29.2 and 31.7 deg-2-theta±0.2 deg 2-theta;
• ii) an XRPD pattern as depicted in FIG. 15;
• iii) a solid state 13C-NMR spectrum with peaks at 176.9, 170.9, 169.1, 148.8 and 133.0 ppm±0.2 ppm;
• iv) a solid state 13C-NMR spectrum having the following chemical shift absolute differences from a peak at 58.0 ppm±2 ppm of 118.9, 112.9, 111.1, 90.8 and 75.0 ppm±0.1 ppm;
• v) a solid state 13C NMR spectrum having chemical shift difference from a peak at 176.9 ppm±1 ppm of 118.7 ppm±0.1 ppm;
• vi) a solid state 13C-NMR spectrum substantially as depicted in FIG. 28;
• or
• combinations of (i)-(vi).