Abstract: The present invention provides salts and crystalline forms of Linsitinib (OSI-906; cis-3-[8-amino-1-(2-phenyl-7-quinolinyl)imidazo[1,5-a]pyrazin-3-yl]-1-methyl-cyclobutanol). These forms of Linsitinib provide increased solubility and improved pharmacokinetic profiles for orally administered pharmaceutical formulations. Accordingly, the invention enables improved methods for treating human insulin-like growth factor-1 receptor (IGF-1R) and insulin receptor (IR) mediated conditions.