Q. Why does it take so long for a generic drug to become available?
Manufacturers of brand-name drugs usually receive patent protection after spending the time and money to research and develop a drug. That protection prevents other companies from making and selling their own version of the drug until the patent expires, which may take up to 20 years. After a patent expires, other companies can create and market their own version of a brand-name drug (based on the process described in the patent) if they receive FDA approval.
Source: FDA
