Association between Nafamostat Mesylate and In-Hospital Mortality in Patients with Coronavirus Disease 2019: A Multicenter Observational Study

The Effectiveness and Safety of Nafamostat Mesylate in the Treatment of COVID-19: a Meta-Analysis

Nafamostat mesylate, a synthetic serine protease inhibitor, has been shown to have antiviral activity against SARS-CoV-2 and anticoagulant properties that may be beneficial in the treatment of COVID-19. We conducted a meta-analysis to evaluate the effectiveness and safety of nafamostat mesylate for the treatment of COVID-19. PubMed, Embase, Cochrane Library, Scopus, Web of Science, medRxiv, and bioRxiv were searched up to July 2023 for studies comparing the outcomes of nafamostat mesylate treatment and no nafamostat mesylate treatment in patients with COVID-19. Mortality, disease progression, and adverse events were analyzed. Six studies involving 16,195 patients were included in the analysis. Meta-analysis revealed no significant difference in mortality (odds ratio [OR]: 0.88, 95% CI: 0.20-3.75, P = 0.86) or disease progression (OR: 2.76, 95% CI: 0.31-24.68, P = 0.36) between groups. However, nafamostat mesylate was associated with an increased risk of hyperkalemia (OR: 7.15, 95% CI: 2.66-19.24, P < 0.0001). Nafamostat mesylate did not improve mortality or morbidity in hospitalized patients with COVID-19. The risk of hyperkalemia is a serious concern that requires monitoring and preventive measures. Further research in different COVID-19 populations is required.

RAndomized Clinical Trial Of NAfamostat Mesylate, A Potent Transmembrane Protease Serine 2 (TMPRSS2) Inhibitor, in Patients with COVID-19 Pneumonia

Even though SARS-CoV-2 was declared by WHO as constituting no longer a public health emergency, the development of effective treatments against SARS-CoV-2 infection remains a critical issue to prevent complications, particularly in fragile patients. The protease inhibitor nafamostat, currently used in Japan and Korea for pancreatitis, owing to its anticoagulant properties for disseminated intravascular coagulation (DIC), is appealing for the treatment of COVID-19 infection, because it potently inhibits the transmembrane protease serine 2 (TMPRSS2) that, after virus binding to ACE-2, allows virus entry into the cells and replication. Moreover, it could prevent the DIC and pulmonary embolism frequently associated with COVID-19 infection. The goal of the RAndomized Clinical Trial Of NAfamostat (RACONA) study, designed as a prospective randomized, double-blind placebo-controlled clinical trial, was to investigate the efficacy and safety of nafamostat mesylate (0.10 mg/kg/h iv for 7 days), on top of the optimal treatment, in COVID-19 hospitalized patients. We could screen 131 patients, but due to the predefined strict inclusion and exclusion criteria, only 15 could be randomized to group 1 (n = 7) or group 2 (n = 8). The results of an ad interim safety analysis showed similar overall trends for variables evaluating renal function, coagulation, and inflammation. No adverse events, including hyperkalemia, were found to be associated with nafamostat. Thus, the RACONA study showed a good safety profile of nafamostat, suggesting that it could be usefully used in COVID-19 hospitalized patients.

Comparing clinical outcomes of ARB and ACEi in patients hospitalized for acute COVID-19

Continued receipt of Renin-Angiotensin-Aldosterone inhibitors in patients with COVID-19 has shown potential in producing better clinical outcomes. However, superiority between ACEi (angiotensin-converting enzyme inhibitors) and ARB (angiotensin II receptor blockers) regarding clinical outcomes in this setting remains unknown. We retrospectively collected data on patients hospitalized for acute COVID-19 using the nationwide administrative database (Diagnosis and Procedure Combinations, DPC). The DPC data covered around 25% of all acute care hospitals in Japan. Patient outcomes, with focus on inpatient mortality, were compared between patients previously prescribed ACEi and those prescribed ARB. Comparisons based on crude, multivariate and propensity-score adjusted analysis were conducted. We examined a total of 7613 patients (ARB group, 6903; ACEi group 710). The ARB group showed lower crude in-hospital mortality, compared to the ACEi group (5% vs 8%; odds ratio, 0.65; 95% CI 0.48-0.87), however not in the multivariate-adjusted model (odds ratio, 0.95; 95% CI 0.69-1.3) or propensity-score adjusted models (odds ratio, 0.86; 95% CI 0.63-1.2). ARB shows potential in reducing hospital stay duration over ACEi in patients admitted for COVID-19, but does not significantly reduce in-hospital mortality. Further prospective studies are needed to draw a definitive conclusion, but continuation of either of these medications is warranted to improve clinical outcomes.

Aprotinin-Drug against Respiratory Diseases

Aprotinin (APR) was discovered in 1930. APR is an effective pan-protease inhibitor, a typical "magic shotgun". Until 2007, APR was widely used as an antithrombotic and anti-inflammatory drug in cardiac and noncardiac surgeries for reduction of bleeding and thus limiting the need for blood transfusion. The ability of APR to inhibit proteolytic activation of some viruses leads to its use as an antiviral drug for the prevention and treatment of acute respiratory virus infections. However, due to incompetent interpretation of several clinical trials followed by incredible controversy in the literature, the usage of APR was nearly stopped for a decade worldwide. In 2015-2020, after re-analysis of these clinical trials' data the restrictions in APR usage were lifted worldwide. This review discusses antiviral mechanisms of APR action and summarizes current knowledge and prospective regarding the use of APR treatment for diseases caused by RNA-containing viruses, including influenza and SARS-CoV-2 viruses, or as a part of combination antiviral treatment.

Intravenous methylprednisolone pulse therapy and the risk of in-hospital mortality among acute COVID-19 patients: Nationwide clinical cohort study

BACKGROUND

Steroids are widely used to modulate the inflammatory reactions associated with coronavirus disease 2019 (COVID-19); however, the optimal upper limit dose of steroid use for acute COVID-19 care remains unclear and currently available data may suffer from a time-dependent bias of no effectiveness or reversed causation given the desperate situation of treatment during this pandemic. Accordingly, the aim of this study was to elucidate the impact of intravenous pulse therapy with methylprednisolone (500 mg or greater per day) on the risk of in-hospital mortality among patients with COVID-19 by controlling for time-dependent bias.

METHODS

We performed a prospective cohort study with 67,348 hospitalised acute COVID-19 patients at 438 hospitals during 2020-2021 in Japan. The impact of intravenous methylprednisolone pulse therapy on the risk of in-hospital mortality was examined based on hazard ratios (HRs) and 95% confidence intervals (95% CIs), with stratification according to the status of invasive mechanical ventilation (iMV). Time-dependent bias was controlled for in a marginal structural model analysis, with reference to patients without methylprednisolone therapy.

RESULTS

During the study period, 2400 patients died. In-hospital mortality rates of iMV-free patients without or with methylprednisolone pulse therapy were 2.3% and 19.5%, and the corresponding values for iMV-receiving patients were 24.7% and 28.6%, respectively. The marginal structural model analysis showed that intravenous pulse therapy with methylprednisolone was associated with a lower risk of in-hospital mortality among patients receiving-iMV (HR 0.59; 95% CI 0.52-0.68). In contrast, pulse therapy with methylprednisolone increased the risk of in-hospital mortality among iMV-free patients (HR 3.38; 95% CI 3.02-3.79). The benefits of pulse therapy for iMV-receiving patients were greater than in those treated with intermediate/higher doses (40-250 mg intravenously) of methylprednisolone (HR 0.80; 95% CI 0.71-0.89).

CONCLUSION

The results of our study suggest that intravenous methylprednisolone showed dose-response efficiencies, and pulse therapy may benefit critically ill patients with acute COVID-19, such as those requiring iMV.

Serious mental illness and in-hospital mortality among hospitalized patients with acute COVID-19: A large-database analysis in Japan

OBJECTIVE

The association of serious mental illness (affective or non-affective psychotic disorders) with higher mortality in patients infected with acute coronavirus disease 2019 (COVID-19) has been suggested. Although this association remains significant after adjusting for medical comorbidities in previous studies, admission clinical status and treatment modalities should be considered as important confounding factors.

METHODS

We aimed to assess whether serious mental illness is associated with in-hospital mortality, in patients with COVID-19 by adjusting for comorbidities, admission clinical status, and treatment modalities. Our nationwide cohort in Japan included consecutive patients admitted to 438 acute care hospitals for laboratory-confirmed acute COVID-19 from January 1, 2020 to November 30, 2021.

RESULTS

Of 67,348 hospitalized patients (mean [standard deviation] age, 54 [18.6] years; 3891 [53.0%] female), 2524 patients (3.75%) had serious mental illness. In-hospital mortality was 282/2524 (11.17%) among patients with serious mental illness, while it was 2118/64,824 (3.27%) in other patients. In the fully adjusted model, serious mental illness was significantly associated with in-hospital mortality (odds ratio, 1.49; 95% CI, 1.27-1.72). E-value analysis confirmed the robustness of the results.

CONCLUSION

Serious mental illness remains a risk for mortality in acute COVID-19 after adjusting for comorbidities, admission clinical status, and treatment modalities. Vaccination, diagnosis, early assessment and treatment should be prioritized for this vulnerable group.

Prevalence and characteristics of antibiotic prescription for acute COVID-19 patients in Japan

COVID-19 is a viral infection and does not require antibiotics. The study aimed to elucidate a prescribing pattern of antibiotics for COVID-19. A nationwide cross-sectional study was conducted in Japan. The Diagnosis and Procedure Combinations (DPC) data was used to collect information, covering 25% of all acute care hospitals in the country. In 140,439 COVID-19 patients, 18,550 (13.21%) patients received antibiotics. Antibiotics were prescribed more often in inpatients (10,809 out of 66,912, 16.15%) than outpatients (7741 out of 73,527, 10.53%) (p < 0.001). Outpatient prescription was significantly associated with older patients (odds ratio [OR], 4.66; 95% confidence interval [CI] 4.41-4.93) and a greater Charlson index (OR with one-point index increase, 1.22; 95% CI 1.21-1.23). Inpatient prescription was significantly associated with older patients (OR 2.10; 95% CI 2.01-2.21), male gender (OR 1.12, 95% CI 1.07-1.18), a greater Charlson index (OR with one-point increase, 1.06; 95% CI 1.05-1.07), requirement of oxygen therapy (OR 3.44; 95% CI 3.28-3.60) and mechanical ventilation (OR 15.09; 95% CI 13.60-16.74). The most frequently prescribed antibiotic among outpatients was cefazolin, while that among inpatients was ceftriaxone. Antibiotic prescription is relatively low for acute COVID-19 in Japan. Antibiotic prescription was associated with older age, multi-morbidity, severe disease, and winter season.

Nafamostat Mesylate for Treatment of COVID-19 in Hospitalised Patients: A Structured, Narrative Review

The search for clinically effective antivirals against the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is ongoing. Repurposing of drugs licensed for non–coronavirus disease 2019 (COVID-19) indications has been extensively investigated in laboratory models and in clinical studies with mixed results. Nafamostat mesylate (nafamostat) is a drug licensed in Japan and Korea for indications including acute pancreatitis and disseminated intravascular coagulation. It is available only for continuous intravenous infusion. In vitro human lung cell line studies with nafamostat demonstrate high antiviral potency against SARS-CoV-2 (half maximal inhibitory concentration [IC50] of 0.0022 µM [compared to remdesivir 1.3 µM]), ostensibly via inhibition of the cellular enzyme transmembrane protease serine 2 (TMPRSS2) preventing viral entry into human cells. In addition, the established antithrombotic activity is hypothesised to be advantageous given thrombosis-associated sequelae of COVID-19. Clinical reports to date are limited, but indicate a potential benefit of nafamostat in patients with moderate to severe COVID-19. In this review, we will explore the pre-clinical, pharmacokinetic and clinical outcome data presently available for nafamostat as a treatment for COVID-19. The recruitment to ongoing clinical trials is a priority to provide more robust data on the safety and efficacy of nafamostat as a treatment for COVID-19.

Haematological and biochemical pathology markers for a predictive model for ITU admission and death from COVID‐19: A retrospective study

Coronavirus disease (COVID‐19) caused by SARS‐CoV‐2 has affected over 227 countries. Changes in haematological and biochemical characteristics in patients with COVID‐19 are emerging as important features of the disease. This study aims to identify the pathological findings of COVID‐19 patients at Bedford Hospital by analysing laboratory parameters that were identified as significant potential markers of COVID‐19. Patients who were admitted to Bedford Hospital from March–July 2020 and had a positive swab for COVID were selected for this study. Clinical and laboratory data were collected using ICE system. Multiple haematological and biochemistry biomarkers were analysed using univariate and multivariate logistic regression to predict intensive therapy unit (ITU) admission and/or survival based on admission tests. Neutrophil‐to‐lymphocyte ratio (NLR) and C‐reactive protein were elevated in most patients, irrespective of ITU status, representing a common outcome of COVID‐19. This was driven by lymphopenia in 80% and neutrophilia in 42% of all patients. Multivariate logistic regression identified an increase in mortality associated with greater age, elevated NLR, alkaline phosphatase activity and hyperkalaemia. With the area under the receiver operating characteristic (ROC) curve of 0.706 +/− 0.04117, negative predictive value (NPV) 66.7% and positive predictive value (PPV) 64.9%. Analysis also revealed an association between increases in serum albumin and potassium concentrations and decreases in serum calcium, sodium and in prothrombin time, with admission to ITU. The area under the ROC curve of 0.8162 +/− 0.0403, NPV 63.3% and PPV 80.5%. These data suggest that using admission (within 4 days) measurements for haematological and biochemical markers, that we are able to predict outcome, whether that is survival or ITU admission.

Pharmacokinetics of Nafamostat, a Potent Serine Protease Inhibitor, by a Novel LC-MS/MS Analysis

Nafamostat, a synthetic serine protease inhibitor, has been used for the treatment of inflammatory diseases such as pancreatitis. Recently, an increasing number of studies have shown the promising antiviral effects of nafamostat for the treatment of coronavirus disease-19 (COVID-19). This study aimed to develop a novel liquid chromatography–tandem mass spectrometry (LC-MS/MS) analysis and to characterize the pharmacokinetics of nafamostat in rats. Nafamostat in the rat plasma was extracted by solid phase extraction, and ¹³C₆-nafamostat was used as an internal standard. The quantification limit of nafamostat in the rat plasma was 0.5 ng/mL. The LC-MS/MS method was fully validated and applied to characterize the pharmacokinetics of nafamostat in rats. Following intravenous injection (2 mg/kg), nafamostat in the plasma showed a multiexponential decline with an average elimination half-life (t_1/2) of 1.39 h. Following oral administration of nafamostat solutions (20 mg/kg) in 10% dimethyl sulfoxide (DMSO) and in 10% DMSO with 10% Tween 80, nafamostat was rapidly absorbed, and the average oral bioavailability was 0.95% and 1.59%, respectively. The LC-MS/MS method and the pharmacokinetic information of nafamostat could be helpful for the further preclinical and clinical studies of nafamostat.