Shortages of medicines: a complex global challenge

Manufacturing quality problems have been implicated in shortages of products produced by a limited number of suppliers, such as propofol,3 imiglucerase and agalsidase â and influenza vaccine.10 Overall, 43% of 127 shortages investigated by the United States Food and Drug Administration were attributed to manufacturing quality problems.13 Where manufacturing is dependent on a small number of facilities, shut-downs for various reasons may cause problems, as has been the case with some radiopharmaceuticals.5 Changes in procurement practices (such as insistence on World Health Organization prequalification status or registration with a stringent regulatory authority) may invalidate a previous supplier, as happened with streptomycin.9 Increased global demand, consolidation of generic production at a few sites, and changes in regulatory standards requiring upgrading of manufacturing plants are all possible reasons for shortages of injectable generic medicines in the USA.2 The IMS Institute for Healthcare Informatics report showed that two-thirds of the products with supply problems only had three or fewer suppliers.11 Gatesman and Smith have claimed that "the main cause of drug shortages is economic", pointing particularly to perverse consequences of Medicare reimbursement policies, which have discouraged the use of low-cost generic chemotherapy agents; however, this assertion remains to be proven.1 A report by the United States Department of Health and Human Services blamed "a substantial expansion in the scope and volume of products produced by the industry that has occurred over a short period of time, without a corresponding expansion in manufacturing capacity".14 It pointed out that manufacturing capacity took time to establish, and that existing manufacturers appeared to be making "strategic decisions about where to deploy production capacity".