The analysis looked at drugs that reported supply chain disruptions between 2017 and 2021 in both countries and found that within 12 months of an initial US report, nearly half resulted in drug shortages in the US, compared to about one third in Canada. There was also a consistently lower risk of shortages in Canada each month after the reports.

“Medication shortages cause real disruptions in patients’ lives, often resulting in discontinuation or delay in treatment,” said lead author Katie J. Suda, PhD, Pharm.D., MS, professor at Pitt School of Medicine and associate director of the Center . for pharmaceutical policy and prescribing. “We can learn from other countries that are successful in mitigating the effects of drug shortages on patients.”

The researchers used reports on supply chain issues from the US Food and Drug Administration, the American Society of Health-System Pharmacists and Health Canada. They then compared these reports to actual drug use in both countries, defining a drug shortage as a decrease in units purchased monthly of at least 33% compared to the average units in the six months preceding the report.

Most reports of supply chain issues were due to manufacturing or transportation issues. However, a quarter of US reports did not specify a reason. Generic medicines accounted for 95% of reports in both countries, and single-source medicines accounted for one in five. However, route of administration, time since Food and Drug Administration (FDA) approval, and drug price per unit did not predict drug shortages..

“The pharmaceutical supply chain is global and every person who touches a drug is essential, from manufacturers to dock workers to pharmacists,” said lead author Mina Tadrous, Pharm.D., PhD, assistant professor at the University of Toronto, Leslie Dan. Faculty of Pharmacy. “There will be shocks to the supply chain and it is important that we cooperate internationally to develop strategies to minimize disruption to patients.”

While the paper did not explore the reasons behind the differences in drug shortages in the two countries, the authors note that Canada has greater cooperation between regulatory agencies, health systems, public payers and other important players such as manufacturers and wholesalers. Canada also uses its pharmaceutical stockpile mechanisms to address drug shortages, while the US stockpile is for acute events such as terrorism or mass casualties. The authors also said that policymakers should consider incentivizing the production of lower-margin generic drugs.

Other authors are Katherine Callaway Kim, MPH, Scott D. Rothenberger, Ph.D., Tina B. Hershey, JD, MPH, Lisa M. Maillart, Ph.D. and Walid F. Gellad, MD, MPH, all of Pitt; Inmaculada Hernandez, Pharm.D., Ph.D., from the University of California San Diego; and Joshua W. Devine, Pharm.D., Ph.D., of Des Moines University.

This research was supported by the Agency for Healthcare Research and Quality (R01 HS027985). Dr. Hernandez has received consulting fees from Bristol Myers Squibb and Pfizer outside of reported work. Dr. Tadrous has received consulting fees from Health Canada and Canada’s Drug Agency (CDA).