Raltegravir Salts and Crystalline Forms Thereof

A crystalline form of Raltegravir potassium selected from:

• a) crystalline Form V of Raltegravir potassium, characterized by data selected from:
• an X-ray powder diffraction pattern having peaks at 8.0, 11.9, 18.2 and 26.6 degrees two theta ±0.2 degrees two theta;
• an X-ray powder diffraction pattern substantially as depicted in FIG. 2;
• a solid-state 13C NMR spectrum with signals at 121.9, 144.0, 149.3 and 170.3±0.2 ppm;
• a solid-state 13C NMR spectrum having chemical shifts differences between the signal exhibiting the lowest chemical shift and another in the chemical shift range of 100 to 180 ppm of 111.9, 134.0, 139.3 and 160.3±0.1 ppm;
• a solid-state 13C NMR spectrum substantially as depicted in FIG. 31;
• and combinations thereof;
• and
• b) crystalline Form IV of Raltegravir potassium, characterized by data selected from:
• an X-ray powder diffraction pattern having peaks at 6.5, 7.5, 8.1, 18.4 and 23.2 degrees two theta ±0.2 degrees two theta;
• an X-ray powder diffraction pattern substantially as depicted in FIG. 1;
• and combinations thereof.