Abstract
BACKGROUND: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak is a serious health concern. Repurposing of existing drugs indicated for other conditions seems to be the first choice for immediate therapeutic management. The quality of early evidence favoring the different treatment options needs to be apprised for informed decision-making. METHODS: In this systematic literature review, we apprised the quality of available evidence for different therapeutic options and also the basis for different treatment guidelines. To include all studies that are in different stages of publication, we also included studies from the preprint servers BioRxiv and MedRxiv and published studies from PubMed. RESULTS: We retrieved 5621 articles and included 22 studies for the systematic review. Based on our study, chloroquine/hydroxychloroquine, either alone or in combination with azithromycin, remdesivir, corticosteroids, convalescent sera, ritonavir/lopinavir, tocilizumab and arbidol were evaluated as therapeutic options. The data from different study designs reveal contradictory findings except for convalescent sera for which the evidence available is only from case series. Based on this early evidence, various national guidelines recommend remdesivir, convalescent sera, corticosteroids and hydroxychloroquine in different subsets of patients. CONCLUSION: Establishing consensus with respect to the end points to be assessed for respiratory viruses may enhance the quality of evidence in case of future pandemics. The systematic review highlighted the lacuna and methodologic deficiency in early clinical evidence and included an update on different therapeutic management guidelines. Further clinical evidence from the ongoing trials may lead to evolution of treatment guidelines with the addition of more therapeutic options.