Organic acid addition salts of S-pindolol

A pharmaceutically acceptable acid addition salt of:

• (i) S-pindolol;
• and
• (ii) benzoic acid,
• wherein the salt is S-pindolol benzoate;
• and
• wherein:
• the S-pindolol benzoate is in the form of S-pindolol benzoate crystalline polymorph Pattern 1 having an x-ray powder diffraction pattern comprising peaks at 8.1°, 11.4°, 12.5°, 12.8°, 15.4° and 17.0°±0.2°2θ;
• or
• the S-pindolol benzoate is in the form of S-pindolol benzoate crystalline polymorph Pattern 2 having an x-ray powder diffraction pattern comprising peaks at 16.9°, 18.9° and 20.1°±0.2°2θ.