Crystalline forms of lanraplenib and methods of making and using the same

A process for preparing crystalline Compound I sesquisuccinate, said process comprising the steps of:

• (i) combining succinic acid and Compound I to form a crystallization mixture;
• (ii) stirring the crystallization mixture;
• and
• (iii) isolating a solid comprising Compound I sesquisuccinate from the crystallization mixture;
• wherein at least 75% by weight of the solid isolated in step (iii) is crystalline Compound I sesquisuccinate, wherein the crystalline Compound I sesquisuccinate exhibits an X-ray powder diffraction pattern comprising at least three characteristic peaks, wherein said characteristic peaks are selected from the group consisting of approximately 8.0, 8.3, 12.1, 16.5, 17.7, 21.8, 23.1, 24.5, 27.1, and 28.4 degrees 2θ.

A process for preparing substantially pure crystalline Compound I sesquisuccinate from a composition comprising one or more crystalline or amorphous forms of Compound I sesquisuccinate and optionally one or more crystalline or amorphous forms of Compound I, said process comprising the steps of:

• (i) treating said composition with aqueous sulfuric acid to form Compound I sulfate;
• and
• (ii) treating said Compound I sulfate with a base to form a first solution of Compound I;
• and
• (iii) filtering said solution of Compound I to remove solids to form a second solution of Compound I.