The present invention relates to a solid oral pharmaceutical composition comprising antipsychotic drug like Brexpiprazole or itspharmaceutically acceptable salts, esters, solvates, polymorphs, enantiomers or mixtures thereof and a process for its preparation. The prior art discloses technical challenges such as photosensitivity and low solubility of Brexpiprazole and low storage stability of the composition. The present invention provides a solid oral pharmaceutical composition of Brexpiprazole with desirable formulation attributes such as thickness, hardness, and dissolution and storage stability.
