Repurposing Sitagliptin for COVID-19 in Adults: Clinical Benefits and An Approach for the Mechanism

Introduction: Dipeptidyl peptidase-4 (DPP4) has been shown to be a functional receptor for MERS-CoV. An interaction between the viral spike protein and DPP4 is thought to facilitate viral entry. We aimed to find out whether sitagliptin, a member of DPP4 inhibitors, would have beneficial effects in COVID-19 patients.Materials and Methods: In this single center retrospective study, we evaluated 58 patients of whom 16 were on sitagliptin treatment. Molecular docking studies were performed to identify possible interactions between ACE2 and sitagliptin.Results: Sitagliptin use shortened the time to clinical recovery about 3.5 and fastened viral clearance more than 5 days. Resolution of all symptoms was achieved on a mean +/- standard error (SE) of 2.50 +/- 0.40 days in sitagliptin (+) group and 5.69 +/- 0.61 days in sitagliptin (-) group (Log-rank test, p< 0.001). PCR tests for SARS-CoV-2 resulted negative in mean +/- SE of 7.50 +/- 0.98 days in sitagliptin (+) and 13.17 +/- 1.07 days in sitagliptin (-) group (Log-rank test, p= 0.003). Compared to day 0, CRP, ferritin and D-dimer levels on days three, five, and seven were significantly lower whereas lymphocyte count was higher in sitagliptin (+) group.Conclusion: Our results suggest that sitagliptin seems to have a potential to be considered for the treatment of COVID-19.