Reasonable assurance must be provided that the generic drug is clinically interchangeable with the nominally equivalent marketed product (5). When the therapeutic activity of the active ingredient is known and correctly reproduced, clinical studies are unnecessary although bioequivalence data will be required. Safety data are provided through reference to the literature, and can be supported by a profile listing impurities and degradation products and stability studies. It is clear that such principles will be meaningless if quality raw materials are not used: whether as active ingredients, excipients, accessory materials, manufacturing intermediaries or primary packaging.