Reasons for supply side driven drug shortages - A mixed-methods study on first-level, higher-level, and root causes from the perspective of marketing authorization holders

Background: Drug shortages impact multiple stakeholders and are detrimental to patient safety. Additionally, drug shortages are an extensive financial burden. In Germany, drug shortages, according to data from the federal ministry for drug and medical products (BfArM), have been increasing by 18% between 2018 and 2021. Studies show that shortages are most frequently supply side driven and that often reasons remain unknown.

Objective: The aim is to develop a holistic understanding of supply side causes for drug shortages in Germany from marketing authorization holders' perspectives and to derive implications for shortage mitigation.

Methods: A mixed-methods research design, with a grounded theory approach based on a structured literature review, BfArM data analysis, and semi-structured interviews, was used.

Results: Input factor supply issues, manufacturing issues, logistics issues, product recalls, and product discontinuations were identified as first-level causes. Furthermore, a theory on their connection to higher-level causes related to business decision-making, as well as root causes linked to regulations, company values, internal processes, market dynamics, external shocks, and macroeconomic factors, was developed.

Conclusion: Actions to mitigate drug shortages in Germany (e.g., improving business processes, diversifying tender criteria) were derived. These may thus increase patient safety and decrease the financial burden on the healthcare system.