key: cord-0700749-xgvtbn2e
authors: Fu, Dian; Cao, Ruiyuan; Zhao, Lei; Li, Wei; Zhong, Wu; Wen, Jiqiu
title: Oral favipiravir for patients with delayed SARS-CoV-2 viral RNA clearance: a case series
date: 2020-09-25
journal: Crit Care
DOI: 10.1186/s13054-020-03288-5
sha: e6208c6bc070e93a832bc0a3ad9e0e5a99834918
doc_id: 700749
cord_uid: xgvtbn2e

nan

From March 26, 2020, we administered oral favipiravir (two doses of 1600 mg on day 1 and 600 mg twice per day on days 2-10 or until SARS-CoV-2 RNA negative) to nine asymptomatic rehabilitation patients. Eight patients were analyzed, and one patient was lost to follow-up due to transfer to another hospital. Of the eight patients included in this analysis, one received the full 10-day course of favipiravir, and seven received 4 to 9 days of favipiravir treatment.

The demographic and clinical characteristics of the eight patients are shown in Table 1 . The median duration of positive detection of SARS-CoV-2 viral RNA in patients before the initiation of favipiravir treatment was 61.0 days (interquartile range, 52.8 to 67.3 days). Coexisting conditions included hypertension (four patients), diabetes (two patients), coronary heart disease (one patient), and malignant tumor (two patients). No interruption of treatment occurred due to adverse reactions.

Over the 14-day follow-up period, the median duration of viral shedding was 3 days (interquartile range, 2 to 6 days) and one patient remained SARS-CoV-2 RNA-positive after 14 days (Fig. 1a) . Notably, seven of eight patients showed a rapid viral clearance within 6 days. One patient kept sustained positive detection of SARS-CoV-2 viral RNA in the upper respiratory tract during the 14-day follow-up ( Fig. 1b) . The persistence of viral RNA detection in individual patients is shown in Fig. 1c . Seven patients were discharged after two consecutive negative viral RNA tests performed at least 24 h apart. The patients were followed for about 1-2 months for the detection of viral nuclear acid in the throat swabs, and the patients remained negative (Fig. 1d) .

It has been reported that the persistence of intestinal SARS-CoV-2 shedding in some patients has led to their re-admission after their pneumonia had resolved [4] . Antiviral therapies appear to be an important means to resolve the problem of viral persistence. Our study suggests that favipiravir is worth further investigation as a common and widely used method of treating asymptomatic convalescent patients and carriers. The small size of this cohort and the relatively short period of follow-up limit the strength of evidence obtained by this study, and the results should be interpreted with caution. However, the rapid elimination of viral RNA in seven of the eight patients strongly suggests that administration of favipiravir may have played a role in terminating the viral RNA persistence. Randomized controlled trials are required to determine the efficacy of favipiravir for terminating SARS-CoV-2 shedding in convalescent patients and healthy carriers with delayed viral clearance. 

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Experimental treatment with favipiravir for COVID-19: an open-label control study. Eng (Beijing)

Persistence of intestinal SARS-CoV-2 infection in patients with COVID-19 leads to re-admission after pneumonia resolved

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We thank the COVID-19 Huoshenshan Study Group and medical care personnel, who assisted in the care of the patients in this program: Xiaoli Xu, Xinyi Xia, Tangfeng 

Authors' contributions WZ and JW contributed to the study design. DF and JW contributed to the collection of clinical data. RC, LZ, and WL contributed to the data analysis and manuscript preparation. All authors revised the manuscript and approved the final version of the manuscript. All authors agreed to authorship contributions.

This work was supported by the National Science and Technology Major Project (2018ZX09711003) and the National Key R&D Program of China (2020YFC0841700).

The datasets generated and/or analyzed during the current study are available from the corresponding authors on request.Ethics approval and consent to participate All studies were approved by the institutional review board of the Huoshenshan Hospital (HSSLL008). Trial registration: ChiCTR2000033491. Registered on 2 June 2020. All patients provided written informed consent to participate in the study.

The authors declare that they have no competing interests.