
==== Front
Medicine (Baltimore)
Medicine (Baltimore)
MD
Medicine
0025-7974
1536-5964
Lippincott Williams & Wilkins Hagerstown, MD

39029053
MD-D-24-05700
00055
10.1097/MD.0000000000039035
3
4900
Research Article
Observational Study
The effect of early versus late remdesivir treatment in hospitalized mild to moderate COVID-19 patients in the Omicron era: A retrospective study
Ryu Byung-Han MD, PhD qudhany@naver.com
ab
Lee Ju Young MD, PhD zzanmery@gmail.com
b
https://orcid.org/0000-0003-2093-3628
Lee Sun Hee MD, PhD c*
a Department of Internal Medicine, Division of Infectious Diseases, Gyeongsang National University Changwon Hospital, Changwon, Korea
b Department of Internal Medicine, Anyang SAM Hospital, Anyang, Korea
c Department of Internal Medicine, Division of Infectious Diseases, Pusan National University School of Medicine and Medical Research Institute, Pusan National University Hospital, Busan, Korea.
* Correspondence: Sun Hee Lee, Department of Internal Medicine, Division of Infectious Diseases, Pusan National University School of Medicine and Medical Research Institute, Pusan National University Hospital, 179 Gudeok-ro, Seo-gu, Busan 49241, Korea (e-mail: zzanmery@gmail.com).
19 7 2024
19 7 2024
103 29 e3903523 5 2024
30 6 2024
01 7 2024
Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.
2024
https://creativecommons.org/licenses/by-nc/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial License 4.0 (CCBY-NC), where it is permissible to download, share, remix, transform, and buildup the work provided it is properly cited. The work cannot be used commercially without permission from the journal.

Although real-world studies have found that remdesivir is effective in preventing poor prognosis, more information is needed on the optimal timing of remdesivir administration in high-risk coronavirus disease 2019 (COVID-19) patients in the Omicron era. From February 2022 to January 2023, a single-center retrospective study was performed in Korea. We compared the clinical characteristics and treatment outcomes between early (remdesivir treatment within 0–3 days from symptom onset) and late (≥ 4 days from symptom onset) treatment groups of patients who received remdesivir monotherapy. Of 284 patients, 225 were classified into the early treatment group and 59 were classified into the late treatment group. The early treatment group had a lower rate of 28-day progression to severe disease than the late treatment group (1.4% vs 7.4%, P = .03). Delaying remdesivir treatment ≥ 4 days from symptom onset (adjusted odds ratio [aOR], 6.17; 95% CI, 1.18–32.44; P = .03) and Charlson comorbidity index ≥ 3 (aOR, 9.62; 95% CI, 1.65–56.10; P = .01) were independent risk factors for 28-day progression to severe disease. Our results suggest that early administration of remdesivir could be associated with better prognosis in COVID-19 patients with the Omicron variant, and within 3 days from symptom onset seems to be the appropriate timing.

antiviral treatment
COVID-19
Omicron
remdesivir
OPEN-ACCESSTRUE
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pmc1. Introduction

Four years have passed since the coronavirus disease 2019 (COVID-19) pandemic began, and the world has gradually returned to its past daily life.[1] However, the end of COVID-19 still seems to be a long way off, and it is expected to cause repetitive community or hospital infections with highly contagious Omicron sub-lineages.[2,3]

The currently available intravenous antiviral drug remdesivir was developed before the Omicron era. As a result, mutations in the RNA-dependent RNA polymerase (target for remdesivir) possessed by the Omicron variant have raised concerns regarding the effectiveness of remdesivir. Fortunately, laboratory studies have confirmed the inhibitory effect of remdesivir against the Omicron variant,[4,5] and the preventive effect of progression to severe disease or death has also been proven in real-world studies conducted during the Omicron era.[6–10]

The appropriate timing of administration is the most important issue in antiviral treatment. The advantage of early antiviral administration in respiratory viral infections has been demonstrated by reduced mortality in influenza virus infection, and neuraminidase inhibitors are recommended within 2 days (48 hours) from symptom onset.[11] A similar strategy can also be applied to COVID-19; rapid antiviral treatment against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) can inhibit early viral replication and prevent progression to severe disease due to a late immune response.[12] Based on randomized controlled studies conducted on this rationale, remdesivir should be administered within 7 days from symptom onset.[13]

There is limited data available on the clinical effectiveness of administering remdesivir earlier than the conventional recommendation within 7 days from symptom onset. A notable study conducted before the Omicron era suggested a potential link between administering remdesivir within 3 days from symptom onset and a reduced mortality rate.[14] Recent studies during the Omicron era have reported clinical benefits for patients who received antiviral treatment earlier than the conventional recommendations.[6,15] However, more information on the appropriate timing of remdesivir use in Omicron patients is needed. Thus, we conducted a comparative analysis between early (remdesivir treatment within 0–3 days from symptom onset) and late (≥ 4 days) treatment groups of patients who received remdesivir monotherapy during the Omicron era.

2. Methods

2.1. Study patients and design

This retrospective observational study was performed at Anyang SAM Hospital (Anyang, Korea), a 320-bed general hospital located in the Seoul metropolitan area. We used data from laboratory-confirmed adult COVID-19 patients admitted to the study site from February 2022 to January 2023, which was the Omicron variant-dominant period in Korea. All study patients did not have hypoxia at the time of admission or diagnosis. The hospitalization of these patients was influenced by several factors: the government policy of fully covering COVID-19 medical expenses, the high proportion of elderly patients and those with underlying diseases, and one-third of the patients were cases of in-hospital transmission.

Patients who met any of the following criteria were excluded from the study: patients who received symptomatic treatment only, severe COVID-19 (radiographic evidence of pneumonia and need for supplemental oxygen to maintain peripheral capillary oxygen saturation (SpO2) ≥ 94%) at the time of admission or diagnosis (in case of in-hospital infection),[16] asymptomatic during the hospital stay, follow-up loss within 7 days from diagnosis, incomplete medical records, or coinfection with another respiratory virus. After that, we excluded patients who received nirmatrelvir-ritonavir (= no detection of 28-day progression to severe disease), molnupiravir (= a small number of patients), or more than one type of antiviral treatment. Finally, patients with mild-to-moderate COVID-19 (mild = symptomatic and SpO2 ≥ 94% in room air, moderate = radiographic evidence of pneumonia and SpO2 ≥ 94% in room air) who received remdesivir monotherapy were included in the study.[16] The included patients were categorized into the early and late treatment groups according to the timing of remdesivir treatment.

2.2. Data collection

We reviewed the electronic medical records of each patient and collected data regarding age, sex, underlying disease, Charlson comorbidity index (CCI), body mass index, high risk of severe COVID-19, vaccination status, prior history of COVID-19, severity of COVID-19 at presentation, prescribed medications (remdesivir, nirmatrelvir-ritonavir, molnupiravir, enoxaparin [10–20 mg/day], and dexamethasone [5–6 mg/day]), and clinical outcomes (length of hospital stay and 28-day progression to severe disease/all-cause mortality/COVID-19 related mortality).

2.3. Definitions

The early treatment group was defined as those who received remdesivir within 3 days from symptom onset. The late treatment group was defined as those who received remdesivir 4 days or later after symptom onset. Symptoms were defined as complaints of one or more of the following: fever (≥37.8°C), chills, myalgia, malaise, headache, sore throat, rhinorrhea, nasal stuffiness, cough, sputum, dyspnea, chest discomfort, nausea/vomiting, diarrhea, dysosmia, or dysgeusia. Immunosuppression was defined as receipt of steroids [≥20 mg prednisone or equivalent/day] for > 2 weeks or use of other immunosuppressants (tacrolimus, mycophenolate mofetil, azathioprine, cyclosporine A, anti-CD3 monoclonal antibody [OKT-3], or anti-TNF-α inhibitor) for > 1 week within the previous 1 month. We used the original CCI[17] rather than the age-adjusted CCI[18] because age can be a significant variable alone for the prognosis of COVID-19 by the Omicron variant. A high risk for severe COVID-19 was defined as having one or more underlying medical conditions, as suggested by the CDC.[19] COVID-19-related mortality was defined as death from no other identifiable cause within 28 days from the onset of COVID-19 symptoms.

2.4. Statistical analysis

For binary variables, the χ2 test or 2-tailed Fisher exact test was used. For continuous variables, the Mann–Whitney U test or Kruskal-Wallis test was used. Continuous variables were expressed as mean ± standard deviation (SD) or as median and interquartile range (IQR). Statistical analysis results were considered significant when the P value was <.05. Multivariate analysis to determine independent risk factors for 28-day progression to severe disease was performed using logistic regression models with statistically significant factors (P value of <.1) in the univariate analysis. All tests were performed using the IBM SPSS Statistics for Windows (version 25.0; IBM Corp., Armonk, NY).

2.5. Ethical considerations

This study was approved by the Institutional Review Board of Anyang SAM Hospital (No. 2023002). Informed consent was waived by the board.

3. Results

3.1. Study patient

From February 2022 to January 2023, 715 laboratory-confirmed adult COVID-19 patients were admitted to the study site. After exclusion, 284 patients were included in the study. These patients were categorized according to the time from symptom onset to antiviral treatment: early treatment group (n = 225) and late treatment group (n = 59) (Fig. 1).

Figure 1. Flow chart of the study.

3.2. Demographic data and underlying condition

The early treatment group was older (mean ± SD years, 72.7 ± 14.6 vs 68.3 ± 16.1, P = .04) and showed a higher proportion of dementia (21.3% vs 8.5%, P = .02), patients at risk of progression to severe disease (96.9% vs 89.8%, P = .03), and mild disease (83.6% vs 67.8%, P = .007) than the late treatment group. The CCI (median [IQR], 1 (0–3) vs 1 (0–2), P = .051) and proportion of patients with CCI ≥ 3 (29.3% vs 18.6%, P = .1) were higher in the early treatment group than in the late treatment group without statistical significance (Table 1).

Table 1 Baseline characteristics of COVID-19 patients who received remdesivir monotherapy in the Omicron era.

Characteristic	Time from symptom onset
to remdesivir treatment	P value	
Early treatment
group: 0–3 d
(n = 225)	Late treatment
group: ≥4 d
(n = 59)	
Age (mean ± SD, yr)	72.7 ± 14.6	68.3 ± 16.1	.04 a	
Male	96 (42.7)	27 (45.8)	.67	
Underlying disease				
 Diabetes mellitus	67 (29.8)	16 (27.1)	.69	
 Hypertension	119 (52.9)	28 (47.5)	.46	
 Liver cirrhosis	10 (4.4)	0	.13	
 Chronic kidney disease	17 (7.6)	9 (15.3)	.07	
 End-stage renal disease	3 (1.3)	0	>.99	
 COPD	25 (11.1)	2 (3.4)	.08	
 Coronary vascular disease	27 (12)	9 (15.3)	.5	
 Cerebrovascular disease	55 (24.4)	8 (13.6)	.07	
 Dementia	48 (21.3)	5 (8.5)	.02 a	
 Solid cancer	21 (9.3)	3 (5.1)	.43	
 Hematologic disease	5 (2.2)	2 (3.4)	.64	
 Immunosuppression	10 (4.4)	6 (10.2)	.11	
 Others	51 (22.7)	11 (18.6)	.51	
Charlson comorbidity index (CCI)b, (median [IQR])	1 (0–3)	1 (0–2)	.051	
 CCI ≥ 3	66 (29.3)	11 (18.6)	.1	
BMI (mean ± SD)	23.0 ± 4.2	23.8 ± 3.9	.18	
 BMI ≥ 30	17 (7.6)	4 (6.8)	>.99	
High risk of severe disease	218 (96.9)	53 (89.8)	.03 a	
Vaccination status, including past infection (mean ± SD)	2.7 ± 1.3	2.4 ± 1.4	.12	
 0	35/218 (16.1)	12/57 (21.1)	.37	
 1–2	26/218 (11.9)	10/57 (17.5)	.26	
 ≥3	157/218 (72.0)	35/57 (61.4)	.12	
COVID-19 reinfection	21 (9.3)	2/58 (3.4)	.18	
COVID-19 grade				
 Mild disease	188 (83.6)	40 (67.8)	.007 a	
 Moderate disease (pneumonia)	37 (16.4)	19 (32.2)	.007 a	
Time from symptom onset to admission
(or isolation), (median [IQR], days)	1 (0–2)	5 (4–6)	<.001 a	
Time from diagnosis to admission
(or isolation), (median [IQR], days)	0 (0–0)	1 (0–4)	<.001 a	
Data are presented as number (%) of patients, unless otherwise indicated. BMI = body mass index, COPD = chronic obstructive lung disease, IQR = interquartile range, SD = standard deviation.

a Statistically significant P values (P < .05) are presented in boldface.

b The original version of Charlson comorbidity index. Not an age-adjusted version.

3.3. Management and clinical outcomes

The early treatment group showed a shorter duration of remdesivir (mean ± SD days, 3.5 ± 1.0 vs 4.0 ± 1.2, P = .001) and lower prescription rate of enoxaparin (12.4% vs 33.9%, P < .001) than the late treatment group. The prescription rate and duration of dexamethasone administration were not significantly different between the 2 groups (Table 2).

Table 2 Management of COVID-19 patients who received remdesivir monotherapy in the Omicron era.

Management	Time from symptom onset to remdesivir treatment	P value	
Early treatment
group: 0–3 d
(n = 225)	Late treatment
group: ≥4 d
(n = 59)	
Duration of remdesivir
(mean ± SD), days	3.5 ± 1.0	4.0 ± 1.2	.001 a	
Duration of remdesivir > 5 d	2 (0.9)	1 (1.7)	.5	
Enoxaparin	28 (12.4)	20 (33.9)	<.001 a	
Duration of enoxaparin
(median [IQR]), days	5.0 (4.0–7.0)	5.0 (4.0–6.0)	.29	
Dexamethasone	14 (6.2)	6 (10.2)	.39	
Duration of dexamethasone
(median [IQR]), days	3.5 (3.0–5.0)	4.5 (2.5–5.0)	.9	
Data are presented as number (%) of patients, unless otherwise indicated. IQR = interquartile range, SD = standard deviation.

The purpose of using dexamethasone in non-severe COVID-19 patients was to control symptoms and manage COPD exacerbations, etc. Dexamethasone was started before the onset of hypoxia. The purpose of using enoxaparin (10–20 mg/day) in non-severe COVID-19 patients was to prevent venous thrombosis in high-risk individuals, such as elderly patients who were immobilized, etc.

a Statistically significant p values (P < .05) are presented in boldface.

Regarding clinical outcomes, length of hospital stay and 28-day all-cause/COVID-19-related mortality were comparable between the 2 groups. The proportion of patients who progressed to severe disease by day 28 was significantly lower in the early treatment group than in the late treatment group (1.4% vs 7.4%, P = .03) (Table 3).

Table 3 Clinical outcomes of COVID-19 patients who received remdesivir monotherapy in the Omicron era.

Outcome	Time from symptom onset to remdesivir treatment	P value	
Early treatment
group: 0–3 d
(n = 225)	Late treatment
group: ≥4 d
(n = 59)	
Length of hospital staysa
(median [IQR]), days	7 (5–8.25)	6 (4–7.25)	.17	
28-day progression to severe disease	3/211 (1.4)	4/54 (7.4)	.03 b	
28-day all-cause mortality	7/216 (3.2)	1/54 (1.9)	>.99	
28-day COVID-19 related mortality	1/216 (0.5)	1/54 (1.9)	.36	
Data are presented as number (%) of patients, unless otherwise indicated. SD = standard deviation.

a Total of 188 hospital admissions only for COVID-19 (134 for 0–3 d group and 54 for ≥ 4 d group), not for other medical needs or in-hospital COVID-19 transmission cases.

b Statistically significant p values (P < .05) are presented in boldface.

3.4. Risk factors for 28-day progression to severe disease

In the univariate analysis, the following variables were found to have P values of <.1: immunosuppression, CCI ≥ 3, late treatment group (= time from symptom onset to remdesivir treatment ≥ 4 days), moderate disease (= presence of pneumonia at the time of admission or diagnosis), and prescription of enoxaparin. In the multivariate analysis using these variables, CCI ≥ 3 (adjusted odds ratio [aOR], 9.62; 95% CI, 1.65–56.10; P = .01) and late treatment group (aOR, 6.17, 95% CI, 1.18–32.44; P = .03) were independent risk factors for 28-day progression to severe disease. Moderate disease was not included as an independent risk factor (aOR, 4.57, 95% CI, 0.90–23.17; P = .07) (Table 4).

Table 4 Risk factors for 28-day progression to severe disease in COVID-19 patients who received remdesivir monotherapy in the Omicron era.

Variable	Univariate analysis
OR (95% CI)	P value	Multivariate analysis
aOR (95% CI)	P value	
Age ≥ 65 yr	1.03 (0.19–5.40)	>.99			
Age ≥ 80 yr	1.38 (0.30–6.28)	.7			
Male	1.68 (0.37–7.68)	.7			
CKD	1.70 (0.20–14.76)	.49			
COPD	NA	>.99			
Dementia	1.71 (0.32–9.06)	.62			
Solid cancer	5.03 (0.92–27.68)	.1			
Immunosuppression	7.54 (1.33–42.61)	.053			
CCI ≥ 3	7.13 (1.35–37.61)	.02 a	9.62 (1.65–56.10)	.01	
High risk of severe disease	NA	>.99			
No past history of vaccination or COVID-19	1.88 (0.35–10.01)	.61			
Time from symptom onset to remdesivir treatment ≥ 4 d	5.55 (1.20–25.58)	.03 a	6.17 (1.18–32.44)	.03 a	
Moderate disease (= pneumonia) at the time of admission or diagnosis	5.83 (1.26–26.92)	.03 a	4.57 (0.90–23.17)	.07	
Enoxaparin	4.48 (0.96–20.83)	.07			
aOR = adjusted odds ratio, CCI = Charlson comorbidity index, CI = confidence interval, NA = not available, OR = odds ratio.

a Statistically significant P values (P < .05) are presented in boldface.

4. Discussion

It is widely understood that the highest amount of SARS-CoV-2 is present on the day symptoms first appear. Therefore, reducing the time from symptom onset to antiviral treatment could be a crucial factor in determining the prognosis of patients with COVID-19.[12,20] A small number of studies conducted before the Omicron era have reported the clinical benefit of the rapid initiation of remdesivir. They include faster clinical improvement, shorter hospital stays, lower rates of intensive care unit admission, mechanical ventilation, and mortality.[14,21–24] However, except for the Spanish study where remdesivir was applied within 3 days from symptom onset, the timing of remdesivir in these studies was not significantly different from that previously recommended, within 7 days from symptom onset.[14]

There are also a few studies on the timing of remdesivir administration conducted after the Omicron era, and they have shown somewhat mixed results. In a study of kidney transplant recipients from a Spanish center, remdesivir treatment within 7 days from symptom onset was related to a lower OR of severe disease or death compared to later treatment (OR, 0.13, 95% CI, 0.03–0.47; P = .002),[25] and Mexican researchers reported lower rates of severe progression in patients who received remdesivir within 7 days from symptom onset than in those who received remdesivir later (4/24, 16.7% vs 3/3, 100%; P = .012).[26] A Polish study showed that early initiation of remdesivir within 5 days from symptom onset led to a statistically significant reduction in the need for oxygen therapy compared to initiation thereafter (131/231, 56.7% vs 27/35, 77.1%; P = .02).[6] In a multicenter study of patients with hematologic disease or cell therapy recipients in Spain, delaying remdesivir treatment for 5 days or later was not related to an increased risk of COVID-19-related death (OR, 1.48, 95% CI 0.54–4.04; P = .43), but they included 28 patients with severe disease, requiring caution in interpretation.[27] Another Spanish study suggested a potential benefit of remdesivir treatment within 3 days from symptom onset in univariate analysis but failed to demonstrate this in multivariate analysis.[28] In summary, except for the Polish study, information on the benefits of administering remdesivir to Omicron patients earlier than the manufacturer instructions has yet to be obtained (Table 5).

Table 5 Studies comparing the effectiveness of early versus late remdesivir treatment in patients with Omicron COVID-19 patients.

Ref	Country	Setting	Omicron
Sub-variant	Study period	Time from symptom onset to treatment: Patient number	Result	
Cacho et al.
[25]
	Spain	Retrospective
Single center
Hospitalized KT recipients	Unknown	2021/11/1~
2022/2/28	0–7 d: 44
≥8 d: not mentioned
	Compared with late use, early remdesivir use (0–7 d from symptom onset) was related with reduced rate of severe disease or death:
OR 0.13 (95% CI 0.03–0.47), P = .002

Compared with late use or null administration of remdesivir, early remdesivir use was associated with reduced rate of severe disease or death in the time-to-event analysis: P value (log-rank) = .003	
Martin-Onraët et al.
[26]	Mexico	Retrospective
Single center
Hematologic malignancy patients (outpatients or hospitalized)	BA.1
BA.2	2021/12/1~
2022/3/31	0–7 d: 24
≥8 d: 3
	Early vs late remdesivir use, comparative analysis
Disease progression:
4/24 (16.7%) vs 3/3 (100%), P = .012	
Dobrowolska et al.
[6]	Poland	Retrospective
Nationwide
Hospitalized patients	Unknown	2022/1/1~
2022/4/30	0–5 d: 231
≥ 6 d: 35
	Early vs late remdesivir use, comparative analysis
Mortality:
25/231 (10.8%) vs 5/35 (14.3%), P > .05
Need for oxygen therapy:
131/231 (56.7%) vs 27/35 (77.1%), P = .02	
Piñana et al.
[27]	Spain	Retrospective
Multicenter
Nationwide
Outpatients with hematologic disease or cell therapy recipients	Unknown	2021/12/27~
2023/5/30	0–4 d: 190
≥ 5 d: 53
	Compared with early use, late remdesivir use (≥ 5 d from symptom onset) was not related with increased risk of COVID-19-related mortality in the univariate analysis:
OR 1.48 (95% CI 0.54–4.04), P = .43

*Twenty-eight severe COVID-19 patients were included.	
Ramos-Rincón et al.
[28]	Spain	Retrospective
Two centers
Outpatient	Unknown	2022/1/1~
2022/9/30	0–3 d: 144
≥ 4 d: 67
	Compared with early use, late remdesivir use (≥ 4 d from symptom onset) was related with tendency of increased rate of 30-day hospitalization or death in the univariate analysis:
OR 2.27 (0.99–10.73), P = .054

*Result of the multivariate analysis:
aOR 2.55 (0.52–10.45), P = .248	
PubMed search date: March 15, 2024 (keywords: Omicron AND remdesivir).

aOR = adjusted odds ratio, HR = hazard ratio, KT = kidney transplant, OR = odds ratio.

This study showed the clinical benefit for high-risk Omicron COVID-19 patients at the earliest time of remdesivir administration, within 3 days from symptom onset. Although the seriousness of COVID-19 is easily overlooked due to the current high vaccination rates, increased population with a history of past infection, and weak toxicity of the Omicron variant, elderly people with chronic diseases are still threatened with significantly high severity and death risks. In other words, the results of this study justify the need for rapid diagnostic tests and antiviral treatment if symptoms of COVID-19 are suspected in high-risk populations. Although it is difficult to prescribe intravenous remdesivir in an outpatient setting, its comparable efficacy to nirmatrelvir-ritonavir and fewer drug interactions make remdesivir an attractive treatment option for COVID-19.[29] In particular, remdesivir is suitable for physically deteriorated COVID-19 patients who cannot take tablets because of reduced oral intake or digestive function in the hospital setting.

This study has several limitations. First, retrospective data collection may have caused various types of biases. To minimize such biases, we excluded data from patients with incomplete medical records and conducted multiple regression analysis. Second, data from a single hospital at a specific location may not be applicable to most Omicron COVID-19 patients. Third, the number of patients in the late treatment group was markedly lower than that of the early treatment group. One can hypothesize that Korean policy of free testing and antiviral drugs had a significant impact, but it may also act as a significant statistical weakness. Fourth, whole-genome sequencing was not performed to identify the Omicron variant sub-lineages in this study. However, given the confirmed efficacy of antiviral agents in BA.1, BA.2, and BA.5, the predominant sub-lineages in Korea during this study period, this is unlikely to be a major problem.[5] Finally, at the time of admission, the late treatment group had significantly more patients with moderate disease than the early treatment group. Although moderate disease was not identified as a significant risk factor through multiple regression analysis with a marginal P value of 0.07, this may lead to controversy regarding the results of the study. Further studies with more patients are required to resolve this issue.

In conclusion, remdesivir should be administered as early as possible, and within 3 days from symptom onset seems to be the appropriate timing. Rapid and active diagnostic testing of high-risk patients should be considered.

Acknowledgments

This study is a revised and supplemented version of the author's doctoral dissertation.

Author contributions

Conceptualization: Byung-Han Ryu, Ju Young Lee, Sun Hee Lee.

Data curation: Byung-Han Ryu, Ju Young Lee.

Formal analysis: Byung-Han Ryu.

Methodology: Byung-Han Ryu, Ju Young Lee, Sun Hee Lee.

Software: Byung-Han Ryu.

Supervision: Sun Hee Lee.

Writing – original draft: Byung-Han Ryu.

Writing – review & editing: Byung-Han Ryu, Ju Young Lee, Sun Hee Lee.

Abbreviations:

aOR adjusted odds ratio

CCI Charlson comorbidity index

CI confidence interval

COVID-19 coronavirus disease 2019

IQR interquartile range

SARS-CoV-2 severe acute respiratory syndrome coronavirus-2

SD standard deviation

SpO2 = peripheral capillary oxygen saturation

The authors have no conflicts of interest to disclose.

All data generated or analyzed during this study are included in this published article [and its supplementary information files].

How to cite this article: Ryu B-H, Lee JY, Lee SH. The effect of early versus late remdesivir treatment in hospitalized mild to moderate COVID-19 patients in the Omicron era: A retrospective study. Medicine 2024;103:29(e39035).
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