The study is an attempt towards developing a formulation of an anti-estrogen drug, which belongs to non-steroidal aromatase inhibitor and which has in-vitro dissolution profile similar to that of reference product. Our target is to develop a dosage form similar to reference product for generic drug application to abbreviated new drug application (ANDA). Immediate drug delivery is required to alter the pharmacokinetics and pharmacodynamics of pharmacological active moieties by using physiological parameters inherent in the selected route of administration. It is also desirable to show rapid onset of action. In case of patient needing a quick action, conventional tablets are unable to release medicament rapidly. The drugs having long half-life and more bioavailability are beneficial for the formulation of immediate release dosage forms. Therefore, the present project involves the development of a formula for an orally administrable immediate release tablet of an anti-estrogen drug, letrozole which must be stable, bio-equivalent to reference listed drug product and has a reproducible and robust process of medication to prevent breast cancer relapse.