Evaluation of the Characteristics of Safety Withdrawal of Prescription Drugs from Worldwide Pharmaceutical Markets-1960 to 1999 *

Abstract

A descriptive analysis was conducted to evaluate prescription drugs withdrawn from worldwide pharmaceutical markets over the past four decades due to safety reasons. The list of drugs, including indication, the duration of marketing, and reasons for withdrawal were examined. Among the 121 products identified, 42.1% were withdrawn from European markets alone, 5.0% from North America, 3.3% from Asia Pacific, and 49.6% from markets in multiple continents. Distributions of these withdrawals in each decade were: 12.4% from the 1960s, 16.5% from the 1970s, 39.7% from the 1980s, and 31.4% from the 1990s. Unfortunately, since the denominators (number of drug approvals) were not readily available, an accurate rate of withdrawal could not be reliably calculated. The most common categories of drugs withdrawn were: Non-Steroidal Anti-Inflammatory Drugs (13.2%), nonnarcotic analgesics (8.3%), antidepressants (7.4%), and vasodilators (5.8%). The top five safety reasons for withdrawals were: hepatic (26.2%), hematologic (10.5%), cardiovascular (8.7%), dermatologic (6.3%), and carcinogenic (6.3%) issues. Among the 87 products for which the timing of marketing was available, the median time on the market was 5.4 years with about one-third withdrawn within the first two years. It is hoped that the current review will stimulate other future research into this important topic. However, due to the intrinsic limitations of the descriptive analysis design, our observations are subject to the availability of data in the public domain. Readers are cautioned to be objective and careful when approaching data of this nature in order not to misinterpret the results due to potential data gaps.