New uses for old drugs: Novel therapeutic options

Since decades, the rational discovery of new medicines has depended on the modification of molecular structures. Introducing a new drug to the market now costs an average of US$ 897 million which includes preclinical and clinical costs before the US FDA (Food and Drug Administration) approval and costs associated with studies conducted after a product has gained such approval. Moreover, the process of approval may take up to 15 years. The new drug may prove to be a loss in terms of its high manufacturing costs if it produces any unacceptable adverse reaction or toxicity in early years of marketing. In such prevailing conditions, discovering new uses for the already-existing time tested drugs with known adverse drug reaction profile may prove to be beneficial for the use of patients. Some older drugs have the potential and offer the advantage of extensive clinical experience in other therapeutic areas. They should be considered as potential partners to the products emerging from more recent research and development. Old drugs are resurfacing with new uses (but often off-label) as the underlying mechanism of diseases become understood. [2] The American Medical Association (AMA) estimates that 40% to 60% of all prescriptions in the United States are written for unapproved/unlabelled purpose. An unapproved use merely indicates the lack of FDA approval and does not imply an improper or illegal use. Unlabeled use is a more appropriate term and is defined as the use of a drug product in doses, patient populations, routes of administration or for indications that are not included in FDA-approved product labeling. Many examples can be quoted to prove its benefits. For example, aspirin, approved by the FDA as a pain * Postgraduate Department of Pharmacology and Therapeutics, Govt. Medical College, Jammu. ** Department of ENT, District Hospital Gandhi Nagar, Jammu.