Why are most generic drugs less expensive than brand name products?

Generic drugs are versions of brand drugs that become available when the brand drug’s patents expire. When a drug patent expires, the original manufacturer does not have exclusive rights to produce the medicine. Other manufacturers can apply to the FDA to produce and sell generic versions of the drug. Because of lower research costs and more competition, the generic drug usually costs less than the brand name drug. Many brand name manufacturers or their subsidiaries make generic medicines.