Abstract: J Antimicrob Chemother doi:10.1093/jac/dkab256 The association of remdesivir and in-hospital outcomes for COVID-19 patients treated with steroids 1 1 *, Yoshihisa Miyamoto2, Masao Iwagami3, Miho Ishimaru3, Mai Takahashi1 and Natalia N. Egorova4 Department of Medicine, Icahn School of Medicine at Mount Sinai, Mount Sinai Beth Israel, New York, NY, USA; 2Division of Nephrology and Endocrinology, The University of Tokyo, Tokyo, Japan; 3Department of Health Services Research, University of Tsukuba, Tsukuba, Japan; 4Department of Population Health Science and Policy, Icahn School of Medicine at Mount Sinai, New York, NY, USA *Corresponding author. E-mail: Toshiki.Kuno@mountsinai.org; kunotoshiki@gmail.com Received 11 May 2021; accepted 25 June 2021 Background: Remdesivir has been shown to decrease SARS-CoV-2 viral loads and the duration of COVID-19 symptoms. However, current evidence regarding the association between remdesivir and in-hospital mortality for patients with COVID-19 steroid treatments is limited. We aimed to investigate whether remdesivir reduces in-hospital mortality among patients with COVID-19 treated with steroids. Methods: In this retrospective multicentre study, we reviewed the medical records of 3372 patients discharged between 1 March 2020 and 30 March 2021, with laboratory confirmed COVID-19 in the Mount Sinai Health System and treated with steroids. We evaluated the effect of remdesivir on the outcomes using propensity score analyses. Subgroup analyses were conducted by stratification of patients by endotracheal intubation and COVID-19 antibody status. Acute kidney injury (AKI) was defined as an absolute serum creatinine increase of 0.3 mg/dL or a relative increase of 50%. Results: Of the 3372 eligible patients, 1336 (39.6%) received remdesivir. After 1:1 propensity score matching (N = 999 pairs), in-hospital mortality was similar between those with and without remdesivir (21.4% versus 21.6%, respectively, P = 0.96). Remdesivir was not significantly associated with in-hospital mortality regardless of endotracheal intubation or COVID-19 antibody status. However, there was a signal that remdesivir was associated with a reduced risk of AKI in the propensity matched analysis (17.5% versus 23.4%, respectively, P = 0.001). Conclusions: Remdesivir was not associated with reduced risk of in-hospital mortality in patients with COVID-19 treated with steroids but potentially associated with decreased risk of AKI. These findings should be confirmed in prospective studies focusing on COVID-19 patients treated with steroids.