A Method for Approximating Future Entry of Generic Drugs

The authors developed and tested a method for predicting generic drug entry that achieved a median predicted market exclusivity of 12.5 years, matching the actual median of 12.5 years across 170 top-selling drugs that lost exclusivity between 2000 and 2012. The method performed accurately for drugs protected by active ingredient patents but overestimated exclusivity for drugs protected only by secondary patents. The procedure demonstrates reasonable utility for forecasting generic entry timing in most cases, though refinements are needed for drugs relying solely on secondary patent protections to improve accuracy in this subset.