Reverse flows within the pharmaceutical supply chain: A classificatory review from the perspective of end-of-use and end-of-life medicines

The Pharmaceutical Supply Chain (PSC) is responsible for considerable environmental and product-value impacts. However, studies on the reverse flows of PSC do not capture the diverse routes of end-of-use and end-of-life medicines (EOU/EOL-M) and how the constraints in the forward supply chain processes and operations impact such reverse flows. This research proposes a classificatory review in which three categories of reverse flows are identified: donations, Reverse Logistics (RL) and Circular Economy (CE). Donations are characterized by explicit philanthropic acts involving corporate reputation or by emergency humanitarian action. RL is boosted by regulatory issues and restricted by business imperatives of the PSC. CE is characterized by informal loops of not expired medicines, mainly due to health professionals’ initiatives (although this may not be clear to participants). This classification emerged from content analysis of 2,622 references found in six databases, from which 127 were selected. Three questions guided the review in each category: (i) what are the elements of the forward PSC processes that impact PSC reverse flows?; (ii) in what stages of the PSC are the reverse flows identified?; (iii) what does the academic literature recommend for improving PSC reverse flows? The literature shows that excessive amounts and inappropriate types of medicines hinder donations. Inventory planning and quality control problems are the main difficulties for medicines RL. The circularity of EOU-M is affected significantly by frequent changes of patient therapies and health conditions, and by failures of healthcare agents in monitoring prescriptions. The proposed classification suggests that the circularity of not expired medicines is not yet researched in the field of logistics, supply chain and procurement, and it is scarcely considered in engineering, and business and management areas, which evokes a call for future research agenda.