Sustainable and Resilient Closed-Loop Drug Supply Chain with Backup Suppliers under Coronavirus Disease Pandemic (COVID-19)

The pharmaceutical industry in Iran suffers from problems such as improper distribution and scheduling of drugs that have delayed the delivery of drugs to patients or on the other hand a huge volume of expired drugs. Also, paying attention to environmental and social issues along with economic ones is a serious approach to achieving sustainable development. Therefore, in this paper, economic, environmental, and social objective functions are considered for drug distribution in Iran according to the amount of demand. The purpose is to design a new model for the drug distribution network following the conditions of an epidemic (COVID-19) and to investigate its effect on the drug supply chain. Besides, in this paper, by adding backup suppliers, in addition to neutralizing the negative effects of Coronavirus, its effects are also examined and analyzed. To obtain the Pareto front, the improved version of augmented Ɛ-constraint (AUGMECON2) has been utilized. Using the proposed model, supply chain managers are able to make tactical decisions (product flow rate in the network) with the most profit, the most positive social impact, reduce greenhouse gasesو and reduce disease transmission. They can also greatly reduce or eliminate the serious problems of their supply chain network by creating resilience and sustainability in their network for the future, in critical situations such as the COVID-19 pandemic. The results showed that the suggested model has suitable efficiency for Coronavirus conditions, and can significantly reduce the destructive and harmful effects of this deadly epidemic