Background Evidence regarding the impact of remdesivir (RDV) on SARS-CoV-2 viral clearance (VC) is scarce. The aim of this study was to compare VC timing in hospitalized COVID-19 patients who did or did not receive RDV. Methods This was a matched-cohort study of patients hospitalized with pneumonia, a SARS-CoV-2-positive nasopharyngeal swab (NPS) at admission, and at least one NPS during follow-up. Patients who received RDV (cases) and those who did not (controls) were matched in a 1:2 ratio by age, sex, and PaO 2 /FiO 2 (P/F) values at admission. NPSs were analyzed using real-time polymerase chain reaction. Time to VC (within 30 days after hospital discharge) was estimated using the Kaplan–Meier curve. A multivariable Cox proportional hazard model was fitted to determine factors associated with VC. Results There were 648 patients enrolled in the study (216 cases and 432 controls). VC was observed in 490 patients (75.6%), with a median time of 25 (IQR 16–34) days. Overall, time to VC was similar between cases and controls (p = 0.519). However, time to VC was different when considering both RDV treatment status and age (p = 0.007). A significant finding was also observed when considering both RDV treatment status and P/F values at admission (p = 0.007). A multivariate analysis showed that VC was associated with a younger age (aHR = 0.990, 95% CI 0.983–0.998 per every 10-year increase in age; p = 0.009) and a higher baseline P/F ratio (aHR=1.275, 95% CI 1.029–1.579; p=0.026), but not with RDV treatment status. Conclusion Time to VC was similar in cases and controls. However, there was a benefit associated with using RDV in regard to time to VC in younger patients and in those with a P/F ratio ≤200 mmHg at hospital admission.

Background Evidence regarding the impact of remdesivir (RDV) on SARS-CoV-2 viral clearance (VC) is scarce. Aim of this study was to compare VC timing in COVID-19 patients who received RDV with those who did not. Methods Matched-cohort study conducted (25 February 2020-15 April 2021) at the IRCSS San Raffaele, Milan, Italy. The study enrolled hospitalized patients with pneumonia and a SARS-CoV-2 positive nasopharyngeal swab (NPS) at admission and at least one NPS during follow-up. Follow-up started at hospital admission and ended at the date of the first negative NPS (within 30 days after discharge). Patients who received RDV (cases) and patients who did not (controls) were matched based on age (±5 years), sex and PaO2/FiO2 (P/F; ±10 mmHg) values at admission. NPS were analyzed with RT-PCR. Results described as median (IQR) or frequency (%). Time to VC was estimated with Kaplan-Meier curve and compared with log-rank test. Results 648 patients were enrolled: 216 cases and 432 controls. Patients’ characteristics at admission are reported in Table 1. VC was observed in 490 patients (75.6%) in a median time of 25 (16-34) days. Overall, time to VC was similar in patients receiving or not receiving remdesivir (p=0.519). However, time to VC was different when considering both the use of RDV (yes vs no) and age (≤ or > 63 years), as shown in Figure 1A. A significant finding was also observed considering the use of RDV and P/F values at admission (≤ or > 200 mmHg), as reported in Figure 1B. Among the 490 patients who reached VC during follow-up, overall time to VC was similar in patients receiving or not receiving RDV (p=0.075; Figure 2A); however, RDV use was associated with a higher probability of VC in the subgroup of patients with P/F admission values ≤ 200mmHg (p=0.035; Figure 2B), in the age group 55-65 years (p=0.025; Figure 2C) and in patients with comorbidities (p=0.028). Time to viral clearance among the 490 patients who reached VC during follow-up. Panel A: time to VC according to RDV use. Panel B: time to VC according to RDV and P/F ratio value at admission. Panel C: time to VC according to RDV in the age group 55-65 years. Conclusion Time to viral clearance was similar in patients receiving or not receiving remdesivir; however the use of RDV was associated with a benefit on time to viral clearance in younger patients and in those with a P/F ratio at admission ≤200 mmHg. Disclosures Vincenzo Spagnuolo, MD, ViiV Healthcare (Other Financial or Material Support, Preparation of educational material) Antonella Castagna, MD, Gilead Sciences (Other Financial or Material Support, Speaking fee)Jansenn-Cilag (Other Financial or Material Support, Speaking fee)MSD (Other Financial or Material Support, Speaking fee)Theratechnologies (Other Financial or Material Support, Speaking fee)ViiV Healthcare (Other Financial or Material Support, Speaking fee)