Repurposed pharmacological agents for the potential treatment of COVID-19: a literature review

BACKGROUND: The COVID-19 pandemic has affected the world extraordinarily. This disease has a potential to cause a significantly severe course of disease leading to respiratory complications, multiple organ failure and possibly death. In the fight against this pandemic-causing disease, medical professionals around the world are searching for pharmacological agents that could treat and prevent disease progression and mortality. To speed the search of promising treatment options, already existing pharmacological agents are repurposed for the potential treatment of COVID-19 and tested in clinical trials. The aim of this literature review is to investigate the efficacy and safety of repurposed pharmacological agents for the treatment of COVID-19 at different pathophysiologic stages of the disease. For this literature review, online-databases PubMed and Google Scholar were utilised. Keywords “COVID-19”, “SARS-CoV-2”, “pathogenesis”, “drug targets”, “pharmacological treatment”, “cytokine storm”, “coagulopathy” and individual drug names were used. Scientific articles, including reviews, clinical trials, and observational cohorts, were collected and analysed. Furthermore, these articles were examined for references to find more clinical trials testing for the potential treatment of COVID-19. In total, 97 references were used to conduct this research paper. RESULTS: The most beneficial pharmacological agent for the treatment of COVID-19 are corticosteroids, especially dexamethasone, for the treatment of mechanically ventilated COVID-19 patients. Other promising agents are remdesivir for the treatment of patients with COVID-19 pneumonia requiring minimal supplemental oxygen therapy, and IL-6 receptor antagonist monoclonal antibodies in severe COVID-19. Lopinavir/ritonavir, as well as chloroquine or hydroxychloroquine with or without azithromycin demonstrate the least efficacy in the treatment of COVID-19. The clinical benefits of the treatment of a COVID-19-specific coagulopathy with increased dosing of anticoagulation need further research and confirmation of randomised controlled trials. CONCLUSION: The search for pharmacological treatment of COVID-19 has elicited great controversy. Whereas drugs like chloroquine, hydroxychloroquine, and lopinavir/ritonavir have not shown proven benefit, the agents remdesivir and dexamethasone are recommended for clinical use for the treatment of COVID-19. Further randomised trials for other pharmacological treatment strategies are awaited.