Oral quetiapine suspension formulations with extended shelf life and enhanced bioavailability

A process for the manufacture of a pharmaceutical composition comprising a pharmaceutically effective amount of quetiapine fumarate particles dispersed in suspension comprising:

• adding purified water to a main vessel,
• adding citric acid monohydrate to the main vessel and mixing until dissolved using a high-shear mixer,
• adding disodium hydrogen phosphate dihydrate to the mam vessel and mixing until dissolved using a high-shear mixer,
• adding sucralose to the main vessel and mixing until dissolved using a high-shear mixer,
• adding the simethicone emulsion to the main vessel and mixing until dispersed using a high-shear mixer,
• adding quetiapine fumarate to the main vessel and mixing using a high-shear mixer until a homogeneous suspension is produced,
• to a separate stage vessel adding propylene glycol,
• to the separate stage vessel adding methyl hydroxybenzoate,
• to the separate stage vessel adding propyl hydroxybenzoate and mixing using a high shear mixer until dissolved,
• to the preservative solution in the separate stage vessel adding xanthan gum and mixing until homogenous using a propeller mixer,
• adding the preservative solution/xanthan gum slurry in the separate stage vessel to the main vessel and mixing using a high-shear mixer until a uniformly thickened suspension is produced,
• adding the lemon flavour to the main vessel and mixing with a high-shear mixer until dispersed,
• checking the pH of the solution (target pH is 5.50), wherein if the pH is outside the range of 5.2-5.8 adjusting the pH until it within this range by using either 10% w/v citric acid monohydrate solution to lower pH or a 10% w/v disodium hydrogen phosphate dihydrate solution to increase the pH,
• adding purified water to final volume and mixing until dispersed using a high-shear mixer,
• filling 152±2 ml of finished product into 180 ml amber glass bottles and closing with child resistant closures.