Efficacy and safety of ReDuNing injection as a treatment for COVID-19 and its inhibitory effect against SARS-CoV-2.

BACKGROUND: Although the rapid emergence of coronavirus disease 2019 (COVID-19) poses a considerable threat to global public health, no specific treatment is available for COVID-19. ReDuNing injection (RDN) is a traditional Chinese medicine known to exert antibacterial, antiviral, antipyretic, and anti-inflammatory effects. In addition, RDN has been recommended in the diagnosis and treatment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-associated pneumonia by the National Health Council and the National Administration of Chinese Medicine. However, there is no information regarding its efficacy against COVID-19. AIM OF STUDY: This study was designed to determine the clinical efficacy of RDN in patients with COVID-19 and characterize its antiviral activity against SARS-CoV-2 in vitro. MATERIALS AND METHODS: A total of 50 adults with COVID-19 were included in this study, and the primary endpoint was recovery from clinical symptoms following 14 days of treatment. General improvements were defined as the disappearance of the major symptoms of infection including fever, fatigue, and cough. The secondary endpoints included the proportion of patients who achieved clinical symptom amelioration on days 7 and 10, time to clinical recovery, time to a negative nucleic acid test result, duration of hospitalization, and time to defervescence. Plaque reduction and cytopathic effect assays were also performed in vitro, and reverse-transcription quantitative PCR was performed to evaluate the expression of inflammatory cytokines (TNF-α, IP-10, MCP-1, IL-6, IFN-α, IFN-γ, IL-2 and CCL-5) during SARS-CoV-2 infection. RESULTS: The RDN group exhibited a shorter median time for the resolution of clinical symptoms (120 vs. 220 h, P < 0.0001), less time to a negative PCR test result (215 vs. 310 h, P = 0.0017), shorter hospitalization (14.8 vs. 18.5 days, P = 0.0002), and lower timeframe for defervescence (24.5 vs. 75 h, P = 0.0001) than the control group. In addition, time to improved imaging was also shorter in the RDN group than in the control group (6 vs.8.9 days, P = 0.0273); symptom resolution rates were higher in the RDN group than in the control group at 7 (96.30% vs. 39.13%, P < 0.0001) and 10 days (96.30% vs. 56.52%, P = 0.0008). No allergic reactions or anaphylactic responses were reported in this trial. RDN markedly inhibited SARS-CoV-2 proliferation and viral plaque formation in vitro. In addition, RDN significantly reduced inflammatory cytokine production in infected cells. CONCLUSIONS: RDN relieves clinical symptoms in patients with COVID-19 and reduces SARS-CoV-2 infection by regulating inflammatory cytokine-related disorders, suggestion that this medication might be a safe and effective treatment for COVID-19.

Development of an antibody-dependent cellular cytotoxicity reporter assay for measuring anti-Middle East Respiratory Syndrome antibody bioactivity.

Middle East Respiratory Syndrome coronavirus (MERS-CoV) is a highly virulent pathogen that causes Middle East Respiratory Syndrome (MERS). Anti-MERS-CoV antibodies play an integral role in the prevention and treatment against MERS-CoV infections. Bioactivity is a key quality attribute of therapeutic antibodies, and high accuracy and precision are required. The major methods for evaluating the antiviral effect of antiviral antibodies include neutralization assays using live viruses or pseudoviruses are highly variable. Recent studies have demonstrated that the antibody-dependent cellular cytotoxicity (ADCC) activity of antiviral antibodies is more consistent with the virus clearance effect in vivo than neutralization activity. However, no reports evaluating the ADCC activity of anti-MERS antibodies have been published to date. Here, we describe the development of a robust and reliable cell-based reporter gene assay for the determination of ADCC activity of anti-MERS antibodies using 293T/MERS cells stably expressing the spike protein of MERS-CoV (MERS-S) as target cells and the engineered Jurkat/NFAT-luc/FcγRIIIa stably expressing FcγRIIIA and NFAT reporter gene as effector cells. According to the ICH-Q2 analytical method guidelines, we carefully optimized the experimental conditions and assessed the performance of our assay. In addition, we found that the ADCC activity of afucosylated anti-MERS antibodies is higher than their fucosylated counterparts. The establishment of this ADCC determination system provides a novel method for evaluating the bioactivity of anti-MERS antibodies and improving ADCC activity through modification of N-glycosylation of the Fc segment.