Nafamostat mesilate for anticoagulation in continuous renal replacement therapy

Risk factors for unplanned weaning of continuous renal replacement therapy in ICU patients: a meta-analysis

OBJECTIVE

To systematically review the risk factors for unplanned weaning during continuous renal replacement therapy in ICU patients.

METHODS

A combination of subject words + free words was used to search the relevant literature published in CNKI, Wanfang, VIP, CBM, PubMed, EMbase, Web of Science, Cochrane Library, Mediline and other databases. The search period was from the establishment of the databases to June 25, 2024. Revman 5.4 software and Stata15.0 software was used to meta-analyze the risk factors for unplanned weaning during continuous renal replacement therapy in ICU patients.

RESULTS

A total of 23 studies were included in this meta-analysis, describing 15 variables, 3793 patients, and using 7197 filters. Meta-analysis results showed that risk factors for unplanned weaning during continuous renal replacement therapy in ICU patients were as follows: Low mean arterial pressure [OR = 1.02, 95%CI (1.00, 1.03), p < 0.05], hypothermia [OR = 3.40, 95%CI (1.78, 6.47), p < 0.05], age (≥60 years) [OR = 4.45, 95%CI (3.18, 6.22), p < 0.05], comorbid underlying disease [OR = 3.63, 95%CI (2.70, 4.88), p < 0.05], agitation [OR = 4.97, 95%CI (3.20, 7.74), p < 0.05], no anticoagulant use [OR = 1.65, 95%CI (1.25, 2.17), p < 0.05], short activated partial prothrombin time [OR = 1.23, 95%CI (1.13, 1.34), p < 0.05], hyper-hematocrit [OR = 1.73, 95%CI (1.13, 2.66), p = 0.01], low ionized calcium concentration [OR = 1.48, 95% CI (1.08, 2.02), p = 0.01], CRRT that was treated at a high dose [OR = 1.42, 95%CI (1.14, 1.76), p < 0.05], mechanical ventilation [OR = 4.25, 95%CI (2.67, 6.77), p < 0.05], and lack of dedicated care [OR = 5.08, 95%CI (2.51, 10.28), p < 0.05]. However, it is unclear whether platelet count, prothrombin activity, and blood flow velocity are risk factors for unplanned weaning during CRRT in ICU patients, and more studies are needed for further validation.

CONCLUSION

Available evidence suggests that a variety of factors contribute to unplanned weaning of CRRT in ICU patients. Early detection of these risk factors is essential for healthcare professionals to develop preventive and curative strategies.

REGISTRATION

This study is registered on the PROSERO website under registration number CRD42024543554.

Pathophysiological dynamics in the contact, coagulation, and complement systems during sepsis: Potential targets for nafamostat mesilate

Sepsis is a life-threatening syndrome resulting from a dysregulated host response to infection. It is the primary cause of death in the intensive care unit, posing a substantial challenge to human health and medical resource allocation. The pathogenesis and pathophysiology of sepsis are complex. During its onset, pro-inflammatory and anti-inflammatory mechanisms engage in intricate interactions, possibly leading to hyperinflammation, immunosuppression, and long-term immune disease. Of all critical outcomes, hyperinflammation is the main cause of early death among patients with sepsis. Therefore, early suppression of hyperinflammation may improve the prognosis of these patients. Nafamostat mesilate is a serine protease inhibitor, which can inhibit the activation of the complement system, coagulation system, and contact system. In this review, we discuss the pathophysiological changes occurring in these systems during sepsis, and describe the possible targets of the serine protease inhibitor nafamostat mesilate in the treatment of this condition.

The role of nafamostat mesylate anticoagulation in continuous kidney replacement therapy for critically ill patients with bleeding tendencies: a retrospective study on patient outcomes and safety

BACKGROUND

Continuous kidney replacement therapy (CKRT) is crucial in the management of acute kidney injury in intensive care units (ICUs). Nonetheless, the optimal anticoagulation strategy for patients with bleeding tendencies remains debated. This study aimed to evaluate patient outcomes and safety of nafamostat mesylate (NM) compared with no anticoagulation (NA) in critically ill patients with bleeding tendencies who were undergoing CKRT.

METHODS

This retrospective study enrolled 2,313 patients who underwent CKRT between March 2013 and December 2022 at the third affiliated hospital in South Korea. After applying the exclusion criteria, 490 patients were included in the final analysis, with 245 patients in the NM and NA groups each, following 1:1 propensity score matching. Subsequently, in-hospital mortality, incidence of bleeding complications, agranulocytosis, hyperkalemia, and length of hospital stay were assessed.

RESULTS

No significant differences were observed between the groups regarding the lengths of hospital and ICU stays or the incidence of agranulocytosis and hyperkalemia. The NM group showed a smaller decrease in hemoglobin levels during CKRT (-1.90 g/dL vs. -2.39 g/dL) and less need for blood product transfusions than the NA group. Furthermore, the NM group exhibited a survival benefit in patients who required transfusion of all three blood products.

CONCLUSION

NM is an effective and safe anticoagulant for CKRT in critically ill patients, especially those requiring transfusion of all three blood products. Although these findings are promising, further multicenter studies are needed to validate them and explore the mechanisms underlying the observed benefits.

Dose of nafamostat mesylate during continuous kidney replacement therapy in critically ill patients: a two-centre observational study

BACKGROUND

Nafamostat mesylate is an anticoagulant used for critically ill patients during continuous kidney replacement therapy (CKRT), characterised by its short half-life. However, its optimal dosage remains unclear. This study aimed to explore the optimal dosage of nafamostat mesylate during CKRT.

METHODS

We conducted a two-centre observational study. We screened all critically ill adult patients who required CKRT in the intensive care unit (ICU) from September 2013 to August 2021; we included patients aged ≥ 18 years who received nafamostat mesylate during CKRT. The primary outcome was filter life, defined as the time from CKRT initiation to the end of the first filter use due to filter clotting. The secondary outcomes included safety and other clinical outcomes. The survival analysis of filter patency by the nafamostat mesylate dosage adjusted for bleeding risk and haemofiltration was performed using a Cox proportional hazards model.

RESULTS

We included 269 patients. The mean dose of nafamostat mesylate was 15.8 mg/hr (Standard deviation (SD), 8.8; range, 5.0 to 30.0), and the median filter life was 18.3 h (Interquartile range (IQR), 9.28 to 36.7). The filter survival analysis showed no significant association between the filter life and nafamostat mesylate dosage (hazard ratio 1.12; 95 CI 0.74-1.69, p = 0.60) after adjustment for bleeding risk and addition of haemofiltration to haemodialysis.

CONCLUSIONS

We observed no dose-response relationship between the dose of nafamostat mesylate (range: 5 to 30 mg/h) and the filter life during CKRT in critically ill patients. The optimal dose to prevent filter clotting safely needs further study in randomised controlled trials.

TRIAL REGISTRATION

Not applicable.

Efficacy and safety of Nafamostat mesylate in patients with end-stage renal failure

BACKGROUND

Recent studies on dialysis anticoagulation therapy in patients with renal failure have shown that Nafamostat mesylate, a broad-spectrum potent serine protease inhibitor, has strong anticoagulation and anti-fiber activity.

AIM

To evaluate the efficacy and safety of Nafamostat mesylate in patients with end-stage renal failure.

METHODS

Seventy-five patients with end-stage renal failure who received hemodialysis at our hospital between January 2020 and August 2021 were selected and divided into the observation group (Nafamostat mesylate for injection, n = 33) and control group (heparin sodium injection, n = 32). General patient data, indicators of clinical efficacy, dialyzer hemocoagulation parameters, coagulation function indices, and hemoglobin concentration and platelet count before and after treatment, and the occurrence of adverse reactions after treatment were compared between the two groups.

RESULTS

The two groups showed no significant differences in general patient data (P > 0.05). The post-treatment effectiveness rate in the control group was lower than that in the observation group (P < 0.05). The two groups showed no significant difference in the number of patients in grade I (P > 0.05), while the number of patients in grade 0 was lower in the control group, and the number of patients in grades II and III was higher in the control group (P < 0.05). The post-treatment prothrombin time, activated partial thromboplastin time, thrombin time, and international normalized ratio values in the control group were higher than those in the observation group, while the fibrinogen level in the control group was lower than that in the observation group (P < 0.05). The two groups showed no significant difference in the platelet count and hemoglobin level before and after treatment (P > 0.05). The total number of post-treatment adverse reactions in the observation group was lower than that in the control group (P < 0.05).

CONCLUSION

Treatment of patients showing end-stage renal failure with Nafamostat mesylate can significantly improve therapeutic efficacy and has high safety and clinical value.

Anticoagulation options for continuous renal replacement therapy in critically ill patients: a systematic review and network meta-analysis of randomized controlled trials

BACKGROUND

Continuous renal replacement therapy (CRRT) is a widely used standard therapy for critically ill patients with acute kidney injury (AKI). Despite its effectiveness, treatment is often interrupted due to clot formation in the extracorporeal circuits. Anticoagulation is a crucial strategy for preventing extracorporeal circuit clotting during CRRT. While various anticoagulation options are available, there were still no studies synthetically comparing the efficacy and safety of these anticoagulation options.

METHODS

Electronic databases (PubMed, Embase, Web of Science, and the Cochrane database) were searched from inception to October 31, 2022. All randomized controlled trials (RCTs) that examined the following outcomes were included: filter lifespan, all-cause mortality, length of stay, duration of CRRT, recovery of kidney function, adverse events and costs.

RESULTS

Thirty-seven RCTs from 38 articles, comprising 2648 participants with 14 comparisons, were included in this network meta-analysis (NMA). Unfractionated heparin (UFH) and regional citrate anticoagulation (RCA) are the most frequently used anticoagulants. Compared to UFH, RCA was found to be more effective in prolonging filter lifespan (MD 12.0, 95% CI 3.8 to 20.2) and reducing the risk of bleeding. Regional-UFH plus Prostaglandin I2 (Regional-UFH + PGI2) appeared to outperform RCA (MD 37.0, 95% CI 12.0 to 62.0), LMWH (MD 41.3, 95% CI 15.6 to 67.0), and other evaluated anticoagulation options in prolonging filter lifespan. However, only a single included RCT with 46 participants had evaluated Regional-UFH + PGI2. No statistically significant difference was observed in terms of length of ICU stay, all-cause mortality, duration of CRRT, recovery of kidney function, and adverse events among most evaluated anticoagulation options.

CONCLUSIONS

Compared to UFH, RCA is the preferred anticoagulant for critically ill patients requiring CRRT. The SUCRA analysis and forest plot of Regional-UFH + PGI2 are limited, as only a single study was included. Additional high-quality studies are necessary before any recommendation of Regional-UFH + PGI2. Further larger high-quality RCTs are desirable to strengthen the evidence on the best choice of anticoagulation options to reduce all-cause mortality and adverse events and promote the recovery of kidney function. Trial registration The protocol of this network meta-analysis was registered on PROSPERO ( CRD42022360263 ). Registered 26 September 2022.

Efficacy and safety of plasma diafiltration: Review of case reports and case series

Plasma diafiltration (PDF), a blood purification procedure that combines dialysis with plasma filtration by a selective membrane, has been used to treat acute liver failure, sepsis, and other acute conditions. We reviewed 14 eligible case reports and case series that examined PDF in 357 patients to assess its efficacy and safety. Fourteen diseases may be indications for PDF. The primary indication in the included studies was acute liver failure without obvious inducement or cause not mentioned. Eighty-three patients reached the primary endpoint (31 deaths, 52 recoveries) and the efficacy was 62.7%. There were large changes in 16 toxins or clinical markers after PDF, including total bilirubin, IL-18, IL-6. In conclusion, PDF appears to be an effective treatment for clearance of bilirubin and other inflammatory mediators in patients with acute liver injury or a disease characterized by a systemic inflammatory state. Randomized controlled trials are needed to compare PDF with other blood purification methods, such as plasma exchange and the Molecular Adsorbent Recirculating System™.

Unfractionated heparin versus nafamostat mesylate for anticoagulation during continuous kidney replacement therapy: an observational study

BACKGROUND

Unfractionated heparin sodium and nafamostat mesylate have long been used as anticoagulants in continuous kidney replacement therapy (CKRT) where citrate is unavailable. This study aimed to determine whether heparin or nafamostat mesylate used during CKRT was associated with a longer filter life.

METHODS

In this single-centre observational study, we included adult patients who required CKRT and used heparin or nafamostat mesylate for their first CKRT in the intensive care unit from September 1, 2013, to December 31, 2020. The primary outcome was filter life (from the start to the end of using the first filter). We used propensity score matching to adjust for the imbalance in patients' characteristics and laboratory data at the start of CKRT and compared the outcomes between the two groups. We also performed restricted mean survival time analysis to compare the filter survival times.

RESULTS

We included 286 patients, 157 patients on heparin and 129 patients on nafamostat mesylate. After propensity score matching, the mean filter life with heparin was 1.58 days (N = 91, Standard deviation [SD], 1.52) and with nafamostat mesylate was 1.06 days (N = 91, SD, 0.94, p = 0.006). Multivariable regression analysis adjusted for confounding factors supported that heparin was associated with a longer filter life compared with nafamostat mesylate (regression coefficient, days, 0.52 [95% CI, 0.15, 0.89]). The between group difference of the restricted mean filter survival time in the matched cohort was 0.29 (95% CI, 0.07-0.50, p = 0.008).

CONCLUSION

Compared to nafamostat mesylate, heparin was associated with one-third to one-half a day longer filter life.

TRIAL REGISTRATION

Not applicable.

Efficacy and safety of nafamostat mesilate anticoagulation in blood purification treatment of critically ill patients: a systematic review and meta-analysis

BACKGROUND

Nafamostat mesilate (NM), a broad-spectrum and potent serine protease inhibitor, can be used as an anticoagulant during extracorporeal circulation, as well as a promising drug effective against coronavirus disease 2019 (COVID-19). We conducted a systematic meta-analysis to evaluate the safety and efficacy of NM administration in critically ill patients who underwent blood purification therapy (BPT).

METHODS

The Cochrane Library, Web of Science and PubMed were comprehensively searched from inception to August 20, 2021, for potential studies.

RESULTS

Four randomized controlled trials (RCTs) and seven observational studies with 2723 patients met the inclusion criteria. The meta-analysis demonstrated that conventional therapy (CT) significantly increased hospital mortality compared with NM administration (RR = 1.25, p = 0.0007). In subgroup analyses, the in-hospital mortality of the NM group was significantly lower than that of the anticoagulant-free (NA) group (RR = 1.31, p = 0.002). The CT interventions markedly elevated the risk ratio of bleeding complications by 45% (RR = 1.45, p = 0.010) compared with NM interventions. In another subgroup analysis, NM used exhibited a significantly lower risk of bleeding complications than those of the low-molecular-weight heparin (LMWH) used (RR = 4.58, p = 0.020). The filter lifespan was decreased significantly (MD = -10.59, p < 0.0001) in the NA groups compared with the NM groups. Due to the poor quality of the included RCTs, these results should be interpreted with caution.

CONCLUSION

Given the better survival outcomes, lower risk of bleeding, NM anticoagulation seems to be a safe and efficient approach for BPT patients and could yield a favorable filter lifespan. More multi-center RCTs with large samples are required for further validation of this study.

Integration of transcriptomics and metabolomics reveals the molecular mechanisms underlying the effect of nafamostat mesylate on rhabdomyolysis-induced acute kidney injury

Objective: To investigate the role and mechanisms of action of nafamostat mesylate (NM) in rhabdomyolysis-induced acute kidney injury (RIAKI). Methods: RIAKI rats were assigned into control group (CN), RIAKI group (RM), and NM intervention group (NM). Inflammatory cytokines and proenkephalin a 119-159 (PENKID) were assessed. Cell apoptosis and glutathione peroxidase-4 (GPX4) were detected using TUNEL assay and immunohistochemical staining. Mitochondrial membrane potential (MMP) was detected by JC-1 dye. The expression of genes and metabolites after NM intervention was profiled using transcriptomic and metabolomic analysis. The differentially expressed genes (DEGs) were validated using qPCR. The KEGG and conjoint analysis of transcriptome and metabolome were used to analyze the enriched pathways and differential metabolites. The transcription factors were identified based on the animal TFDB 3.0 database. Results: Serum creatinine, blood urea nitrogen, and PENKID were remarkably higher in the RM group and lower in the NM group compared to the CN group. Pro-inflammatory cytokines increased in the RM group and notably decreased following NM treatment compared to the CN group. Tubular pathological damages were markedly attenuated and renal cell apoptosis was reduced significantly in the NM group compared to the RM group. The expression of GPX4 was lower in the RM group compared to the CN group, and it increased significantly after NM treatment. A total of 294 DEGs were identified in the RM group compared with the NM group, of which 192 signaling pathways were enriched, and glutathione metabolism, IL-17 signaling, and ferroptosis-related pathways were the top-ranking pathways. The transcriptional levels of Anpep, Gclc, Ggt1, Mgst2, Cxcl13, Rgn, and Akr1c1 were significantly different between the NM and RM group. Gclc was the key gene contributing to NM-mediated renal protection in RIAKI. Five hundred and five DEGs were annotated. Compared with the RM group, most of the upregulated DEGs in the NM group belonged to Glutathione metabolism, whereas most of the downregulated DEGs were related to the transcription factor Cytokine-cytokine receptor interaction. Conclusion: NM protects the kidneys against RIAKI, which is mainly associated with NM mediated regulation of glutathione metabolism, inflammatory response, ferroptosis-related pathways, and the related key DEGs. Targeting these DEGs might emerge as a potential molecular therapy for RIAKI.

Comparison of nafamostat mesilate to citrate anticoagulation in pediatric continuous kidney replacement therapy

BACKGROUND

Regional citrate anticoagulation (RCA) is the preferred continuous kidney replacement therapy (CKRT) anticoagulation strategy for children in the USA. Nafamostat mesilate (NM), a synthetic serine protease, is used widely for CKRT anticoagulation in Japan and Korea. We compared the safety and efficacy of NM to RCA for pediatric CKRT.

METHODS

Starting June 2019, the most recent 100 medical records of children receiving CKRT with either RCA or NM were reviewed retrospectively, at one children's hospital in Japan (NM) and one in the USA (RCA). The number of hours a single CKRT filter was in use, was the primary outcome. Safety was assessed by bleeding complications for the NM group and citrate toxicity leading to RCA discontinuation or electrolyte imbalance in the RCA group.

RESULTS

Eighty patients received NM and 78 patients received RCA. Median filter life was longer for the NM group (NM: 38 [22, 74] vs. RCA: 36 [17, 66] h, p = 0.02). When filter life was censored for discontinuation other than clotting, the 60-h survival rate was higher for RCA (71% vs. 54%). The hazard ratio comparing NM over RCA varied over time (HR 0.7; 0.2-1.5, p = 0.33 at 0 h to HR 5.5; 1.3-23.7, p = 0.334 at 72 h). The lack of difference in filter survival persisted controlling for filter surface area, catheter diameter, and pre-CKRT platelet count. Major bleeding rates did not differ between groups (NM: 5% vs. RCA: 9%).

CONCLUSIONS

RCA and NM provide satisfactory anticoagulation for CKRT in children with no difference in major bleeding rates. A higher resolution version of the Graphical abstract is available as Supplementary information.

Anticoagulation with nafamostat mesilate during extracorporeal life support

Nafamostat mesylate (NM) affects coagulation and fibrinolysis and impedes obesity-associated protein demethylase activity, which regulates Na+/K+ transport properties and the NF-κB signaling pathway. NM significantly decreases macrophage, neutrophil, and T lymphocyte infiltration, thereby reducing inflammation and apoptosis after reperfusion and promoting recovery in patients with severe conditions such as near-fatal asthma and cardiac arrest. Extracorporeal life support (ECLS) devices are used for cardiac and/or pulmonary support as a bridge to recovery, decision, surgery, or transplant in patients with refractory cardio-circulatory or respiratory diseases and provide essential opportunities for organ support and patient survival. However, they can lead to some potential adverse events such as hemorrhage and thrombosis. NM provides a sustained innate immune response of coagulation and anti-inflammation in extracorporeal circuits, principally due to its activation of the contact and complement systems. Heparin is the main anticoagulant used in extracorporeal circuits; however, it may cause massive bleeding and heparin-induced thrombocytopenia. Although no antidote is available, NM has a very short half-life of approximately 8-10 min and might have positive effects on patients who require coagulation and anti-inflammation. NM has been used for anticoagulation in continuous renal replacement therapy, extracorporeal membrane oxygenation, hemodialysis, and left ventricular assist devices. In this review, we focused on the pharmacology, monitoring parameters, and considerations for the special use of NM in patients receiving ECLS. Our findings suggest that systemic anticoagulation with NM during ECLS might be a feasible and safe alternative with several advantages for critically ill patients with high-risk bleeding and might improve their prognosis.

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.

Use of nafamostat mesilate for anticoagulation during extracorporeal membrane oxygenation: A systematic review

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) represents an advanced option for supporting refractory respiratory and/or cardiac failure. Systemic anticoagulation with unfractionated heparin (UFH) is routinely used. However, patients with bleeding risk and/or heparin-related side effects may necessitate alternative strategies: among these, nafamostat mesilate (NM) has been reported.

METHODS

We conducted a systematic literature search (PubMed and EMBASE, updated 12/08/2021), including all studies reporting NM anticoagulation for ECMO. We focused on reasons for starting NM, its dose and the anticoagulation monitoring approach, the incidence of bleeding/thrombosis complications, the NM-related side effects, ECMO weaning, and mortality.

RESULTS

The search revealed 11 relevant findings, all with retrospective design. Of these, three large studies reported a control group receiving UFH, the other were case series (n = 3) or case reports (n = 5). The main reason reported for NM use was an ongoing or high risk of bleeding. The NM dose varied largely as did the anticoagulation monitoring approach. The average NM dose ranged from 0.46 to 0.67 mg/kg/h, but two groups of authors reported larger doses when monitoring anticoagulation with ACT. Conflicting findings were found on bleeding and thrombosis. The only NM-related side effect was hyperkalemia (n = 2 studies) with an incidence of 15%-18% in patients anticoagulated with NM. Weaning and survival varied across studies.

CONCLUSION

Anticoagulation with NM in ECMO has not been prospectively studied. While several centers have experience with this approach in high-risk patients, prospective studies are warranted to establish the optimal space of this approach in ECMO.

The role of nafamostat mesilate as a regional anticoagulant during extracorporeal membrane oxygenation

BACKGROUND

Anticoagulation during extracorporeal membrane oxygenation (ECMO) usually is required to prevent thrombosis. The aim of this study was to investigate the usefulness of nafamostat mesilate (NM) as a regional anticoagulant during veno-arterial ECMO (VA-ECMO) treatment.

METHODS

We retrospectively reviewed the medical records of 16 patients receiving VA-ECMO and NM from January 2017 to June 2020 at Haeundae Paik Hospital. We compared clinical and laboratory data, including activated partial thromboplastin time (aPTT), which was measured simultaneously in patients and the ECMO site, to estimate the efficacy of regional anticoagulation.

RESULTS

The median patient age was 68.5 years, and 56.3% of patients were men. Cardiovascular disease was the most common primary disease (75.0%) requiring ECMO treatment, followed by respiratory disease (12.5%). The median duration of ECMO treatment was 7.5 days. Among 16 patients, seven were switched to NM after first using heparin as an anticoagulation agent, and nine received only NM. When comparing aPTT values in the NM group between patients and the ECMO site, that in patients was significantly lower than that at the ECMO site (73.57 vs. 79.25 seconds; P=0.010); in contrast, no difference was observed in the heparin group.

CONCLUSIONS

NM showed efficacy as a regional anticoagulation method by sustaining a lower aPTT value compared to that measured at the ECMO site. NM should be considered as a safer regional anticoagulation method in VA-ECMO for patients at high risk of bleeding.

Broad antiviral and anti-inflammatory efficacy of nafamostat against SARS-CoV-2 and seasonal coronaviruses in primary human bronchiolar epithelia

Antiviral strategies that target host systems needed for SARS-CoV-2 replication and pathogenesis may have therapeutic potential and help mitigate resistance development. Here, we evaluate nafamostat mesylate, a potent broad-spectrum serine protease inhibitor that blocks host protease activation of the viral spike protein. SARS-CoV-2 is used to infect human polarized mucociliated primary bronchiolar epithelia reconstituted with cells derived from healthy donors, smokers and subjects with chronic obstructive pulmonary disease. Nafamostat markedly inhibits apical shedding of SARS-CoV-2 from all donors (log10 reduction). We also observe, for the first-time, anti-inflammatory effects of nafamostat on airway epithelia independent of its antiviral effects, suggesting a dual therapeutic advantage in the treatment of COVID-19. Nafamostat also exhibits antiviral properties against the seasonal human coronaviruses 229E and NL6. These findings suggest therapeutic promise for nafamostat in treating SARS-CoV-2 and other human coronaviruses.

Cytokine expressions of spinal cord injury treated by neurotropin and nafamostat mesylate

Background

Spinal cord injury (SCI) leads to severe physical disability and sensory dysfunction. Neurotropin (NTP) has been used clinically to alleviate neuropathic pain, while nafamostat mesylate (NM) used clinical on pancreatitis patients through inhibiting synthetic serine protease. Our previous studies showed that NTP and NM were able to repair SCI. However, the underlying mechanism has not been fully explored after treatment with these 2 different drugs.

Methods

The drugs NTP and NM were administered on a contusion SCI Wistar rat model. Cytokine array analysis was performed to describe the changes of 67 proteins after acute SCI. Hierarchical clustering and volcano plot analysis were conducted to clarify protein change profiles. The differently expressed proteins related to biological processes were analyzed by functional protein association networks, Gene Ontology and pathway analysis. Flow cytometric analysis was detected to reflect the activation of immune system after drug intervention, while withdrawal threshold and BBB score were detected to evaluated the mechanical allodynia and functional recovery after SCI.

Results

HGF, β-NGF, and activin were the 3 most upregulated proteins, while the receptor for RAGE, IL-1α, and TNF-α were the 3 most downregulated proteins after NTP treatment. Adiponectin, decorin and CTACK were the 3 most upregulated proteins, while RAGE, IL-1α, and IL-1β were the 3 most downregulated proteins in the NM group. Number of lymphocytes was decreased while BBB score was increased both in NTP and NM group. But only NTP could improve mechanical pain threshold after SCI.

Conclusions

The PI3K-Akt, Jak-STAT signaling pathway and apoptosis might participate in SCI restoration by NTP, while the MAPK and NOD-like receptor signaling pathway may participated in repairing SCI with NM. We concluded that NTP regulated the microenvironment via a neuroprotective effect and inhibition of inflammation to repair SCI, while NM healed SCI through an anti-inflammatory effect. Both NTP and NM could down-regulate the activation of immune system and improve the functional recovery while only NTP could improve the pathological neuralgia after SCI. Elucidating the molecular mechanisms of these 2 clinical drugs indicates that they their expected to be effective clinical treatment for SCI.

Continuous renal replacement therapy without anticoagulation in critically ill patients at high risk of bleeding: A systematic review and meta-analysis

The current clinical guideline recommends continuous renal replacement therapy (CRRT) proceed without anticoagulation in patients with contraindication to citrate and increased bleeding risk. Nevertheless, the efficacy of anticoagulation-free CRRT remains inconsistent. The purpose of our present systematic review is to evaluate the efficacy and safety of anticoagulant-free CRRT based on the current literatures. The primary outcomes were filter lifespan and risk factors for filter failure. Seventeen observational studies and three randomized controlled trials were included in our present meta-analysis. There was no significant difference in filter lifespan and azotemic control between the anticoagulation-free and systemic heparin group. The regional citrate anticoagulation (RCA) protocol seems to be superior to the anticoagulation-free protocol in terms of filter lifespan (WMD -23.01, 95% CI [-28.62, -17.39], p < 0.001; I²  = 0%, p = 0.53) and azotemic control. Nafamostat protocol could significantly prolong filter lifespan (WMD -8.4, 95% CI [-9.9, -6.9], p < 0.001; I²  = 33.7%, p = 0.21) as compared with anticoagulation-free protocol without better azotemic control. The conventional coagulation parameters showed poor predictive performence for filter failure and the necessity of anticoagulants use before CRRT. Currently, the optimal choice of anticoagulation strategy for critically ill patients with increased bleeding risk could be RCA under close monitoring.

Targeting Crucial Host Factors of SARS-CoV-2

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread worldwide since its first incidence in Wuhan, China, in December 2019. Although the case fatality rate of COVID-19 appears to be lower than that of SARS and Middle East respiratory syndrome (MERS), the higher transmissibility of SARS-CoV-2 has caused the total fatality to surpass other viral diseases, reaching more than 1 million globally as of October 6, 2020. The rate at which the disease is spreading calls for a therapy that is useful for treating a large population. Multiple intersecting viral and host factor targets involved in the life cycle of the virus are being explored. Because of the frequent mutations, many coronaviruses gain zoonotic potential, which is dependent on the presence of cell receptors and proteases, and therefore the targeting of the viral proteins has some drawbacks, as strain-specific drug resistance can occur. Moreover, the limited number of proteins in a virus makes the number of available targets small. Although SARS-CoV and SARS-CoV-2 share common mechanisms of entry and replication, there are substantial differences in viral proteins such as the spike (S) protein. In contrast, targeting cellular factors may result in a broader range of therapies, reducing the chances of developing drug resistance. In this Review, we discuss the role of primary host factors such as the cell receptor angiotensin-converting enzyme 2 (ACE2), cellular proteases of S protein priming, post-translational modifiers, kinases, inflammatory cells, and their pharmacological intervention in the infection of SARS-CoV-2 and related viruses.

Mast cell tryptase - Marker and maker of cardiovascular diseases

Mast cells are tissue-resident cells, which have been proposed to participate in various inflammatory diseases, among them the cardiovascular diseases (CVDs). For mast cells to be able to contribute to an inflammatory process, they need to be activated to exocytose their cytoplasmic secretory granules. The granules contain a vast array of highly bioactive effector molecules, the neutral protease tryptase being the most abundant protein among them. The released tryptase may act locally in the inflamed cardiac or vascular tissue, so contributing directly to the pathogenesis of CVDs. Moreover, a fraction of the released tryptase reaches the systemic circulation, thereby serving as a biomarker of mast cell activation. Actually, increased levels of circulating tryptase have been found to associate with CVDs. Here we review the biological relevance of the circulating tryptase as a biomarker of mast cell activity in CVDs, with special emphasis on the relationship between activation of mast cells in their tissue microenvironments and the pathophysiological pathways of CVDs. Based on the available in vitro and in vivo studies, we highlight the potential molecular mechanisms by which tryptase may contribute to the pathogenesis of CVDs. Finally, the synthetic and natural inhibitors of tryptase are reviewed for their potential utility as therapeutic agents in CVDs.

The Japanese clinical practice guideline for acute kidney injury 2016

Acute kidney injury (AKI) is a syndrome which has a broad range of etiologic factors depending on different clinical settings. Because AKI has significant impacts on prognosis in any clinical settings, early detection and intervention is necessary to improve the outcomes of AKI patients. This clinical guideline for AKI was developed by a multidisciplinary approach with nephrology, intensive care medicine, blood purification, and pediatrics. Of note, clinical practice for AKI management which was widely performed in Japan was also evaluated with comprehensive literature search.

The Japanese Clinical Practice Guideline for acute kidney injury 2016

Acute kidney injury (AKI) is a syndrome which has a broad range of etiologic factors depending on different clinical settings. Because AKI has significant impacts on prognosis in any clinical settings, early detection and intervention are necessary to improve the outcomes of AKI patients. This clinical guideline for AKI was developed by a multidisciplinary approach with nephrology, intensive care medicine, blood purification, and pediatrics. Of note, clinical practice for AKI management which was widely performed in Japan was also evaluated with comprehensive literature search.

Validation of Nafamostat Mesilate as an Anticoagulant in Extracorporeal Membrane Oxygenation: A Large-Animal Experiment

Background

Unfractionated heparin is commonly used for anticoagulation in extracorporeal membrane oxygenation (ECMO). Several studies have shown that nafamostat mesilate (NM) has comparable clinical outcomes to unfractionated heparin. This study compared anticoagulation with NM and heparin in a large-animal model.

Methods

Beagle dogs (n=8; weight, 6.5-9 kg) were placed on venovenous ECMO. Blood samples were taken every hour and the following parameters were compared: hemoglobin level, activated partial thromboplastin time (aPTT), thromboelastography (TEG) data, platelet function, and inflammatory cytokine levels.

Results

In both groups, the aPTT was longer than the baseline value. Although the aPTT in the NM group was shorter than in the heparin group, the TEG parameters were similar between the 2 groups. Hemoglobin levels decreased in both groups, but the decrease was less with NM than with heparin (p=0.049). Interleukin (IL)-1β levels significantly decreased in the NM group (p=0.01), but there was no difference in the levels of tumor necrosis factor alpha or IL-10 between the 2 groups.

Conclusion

NM showed a similar anticoagulant effect to that of unfractionated heparin, with fewer bleeding complications. NM also had anti-inflammatory properties during ECMO. Based on this preclinical study, NM may be a good alternative candidate for anticoagulation in ECMO.

Continuous Renal Replacement Therapy and Anticoagulation: What Are the Options?

Continuous renal replacement therapy is currently used as a standard treatment for acute kidney injury in the intensive care unit, particularly for patients with unstable hemodynamic status. Because this therapy is continuous, for days or weeks, and the extracorporeal blood circuit is large, the circuit is prone to clotting. Several methods of keeping the extracorporeal circuit patent are available, including heparin infusion, flushes with physiological saline, use of thrombin inhibitors, and citrate. This article reviews methods for continuous renal replacement therapy, anticoagulation, efficacy, and implications for bedside critical care.

Nafamostat mesilate attenuates inflammation and apoptosis and promotes locomotor recovery after spinal cord injury

AIM

Spinal cord injury (SCI) leads to severe neural damage for which there is currently no effective treatment. Exploration of the neuroprotective effect among clinically approved drugs will speed up clinical translation of SCI. Nafamostat mesilate (NM) as a synthetic serine protease inhibitor has been used clinically in pancreatitis treatments. However, its effectiveness in SCI is unknown. The aim of this study was to confirm the efficacy of NM in ameliorating SCI.

METHODS

Intraperitoneal administration of NM was performed on a contusion SCI model in Wistar rat. Hematoxylin and eosin staining (H&E staining) and Luxol fast blue (LFB) staining were used to observe the histological lesions. Apoptosis was examined by TUNEL staining, Annexin V-FITC/PI, caspase-3, and Bcl-2. Cytokines and neurotrophins were tested by Western blot. Locomotion recovery assessed by hindlimb BBB score and the inclined plane test.

RESULTS

Nafamostat mesilate treatment significantly improved locomotion recovery as assessed by hindlimb BBB scores and the inclined plane test. H&E staining and LFB staining showed a significant increase in spared tissue in both gray matter and white matter. NM decreased the expression of the proinflammatory cytokines TNF-α and IL-6. In addition, apoptosis was also significantly decreased, as shown by TUNEL staining and Annexin V-FITC/PI and by Western blotting for caspase-3 and Bcl-2 expression. Due to the mechanism of action of NM as a serine protease inhibitor, the drug decreased thrombin expression in the damaged spinal cord. Furthermore, NM increased the expression of neurotrophins (NT-3, BDNF, and NGF).

CONCLUSIONS

Upon NM treatment, the functional and histological outcomes were improved, and microenvironment upon SCI was modulated. As a clinically approved drug, NM holds promise for clinical use after spinal cord injury.

Tryptase inhibitors: a patent review

INTRODUCTION

Tryptase is one of the main serine-proteinases located in the secretory granules of mast cells, and is released through degranulation, which is involved in the pathogenesis of allergic inflammatory disease, cardiovascular diseases, lung fibrosis and tumor. Therefore, inhibitors targeting tryptase may represent a new direction for the treatment of allergic inflammatory disease and other diseases. Areas covered: In this article, we discussed the history and development of tryptase inhibitors and described a variety of tryptase inhibitors via their structures and biological importance in clinical studies and drug development for tryptase-related diseases. Expert opinion: Initial tryptase inhibitors based on indole structure as the hydrophobic substituent on a benzylamine-piperidine template have low specificity and poor bioavailability. Therefore, designing new and specific inhibitors targeting tryptase should be involved in future clinical studies. Modifications toward indoles with varying N-substitution, introducing an amide bond, and growing the chain length contribute to an increase in the specific selectivity and potency of tryptase inhibitors. Tryptase has become the research hotspot to explore many related diseases. Therefore, there has been growing appreciation for the potential importance of the tryptase inhibitors as a target for treating these diseases.

Non anti-coagulant factors associated with filter life in continuous renal replacement therapy (CRRT): a systematic review and meta-analysis

BACKGROUND

Optimising filter life and performance efficiency in continuous renal replacement therapy has been a focus of considerable recent research. Larger high quality studies have predominantly focussed on optimal anticoagulation however CRRT is complex and filter life is also affected by vascular access, circuit and management factors. We performed a systematic search of the literature to identify and quantify the effect of vascular access, circuit and patient factors that affect filter life and presented the results as a meta-analysis.

METHODS

A systematic review and meta-analysis was performed by searching Pubmed (MEDLINE) and Ovid EMBASE libraries from inception to 29th February 2016 for all studies with a comparator or independent variable relating to CRRT circuits and reporting filter life. Included studies documented filter life in hours with a comparator other than anti-coagulation intervention. All studies comparing anticoagulation interventions were searched for regression or hazard models pertaining to other sources of variation in filter life.

RESULTS

Eight hundred nineteen abstracts were identified of which 364 were selected for full text analysis. 24 presented data on patient modifiers of circuit life, 14 on vascular access modifiers and 34 on circuit related factors. Risk of bias was high and findings are hypothesis generating. Ranking of vascular access site by filter longevity favours: tunnelled semi-permanent catheters, femoral, internal jugular and subclavian last. There is inconsistency in the difference reported between femoral and jugular catheters. Amongst published literature, modality of CRRT consistently favoured continuous veno-venous haemodiafiltration (CVVHD-F) with an associated 44% lower failure rate compared to CVVH. There was a trend favouring higher blood flow rates. There is insufficient data to determine advantages of haemofilter membranes. Patient factors associated with a statistically significant worsening of filter life included mechanical ventilation, elevated SOFA or LOD score, elevations in ionized calcium, elevated platelet count, red cell transfusion, platelet factor 4 (PF-4) antibodies, and elevated fibrinogen. Majority of studies are observational or report circuit factors in sub-analysis. Risk of bias is high and findings require targeted investigations to confirm.

CONCLUSION

The interaction of patient, pathology, anticoagulation, vascular access, circuit and staff factors contribute to CRRT filter life. There remains an ambiguity from published data as to which site and side should be the first choice for vascular access placement and what interaction this has with patient factors and timing. Early consideration of tunnelled semi-permanent access may provide optimal filter life if longer periods of CRRT are anticipated. There remains an absence of robust evidence outside of anti-coagulation strategies despite over 20 years of therapy delivery however trends favour CVVHD-F over CVVH.

Comparison of nafamostat mesilate and unfractionated heparin as anticoagulants during continuous renal replacement therapy

PURPOSE

Nafamostat mesilate (NM) can be used as a regional anticoagulant for continuous renal replacement therapy (CRRT). The primary aim of this study was to assess the association of the use of NM with risk of bleeding complications and compare it with the use of unfractionated heparin (UFH).

METHODS

We conducted a single-center retrospective observational study. We included adult patients who required CRRT in our intensive care unit from 2011 to 2013. The primary outcome was the risk of bleeding complications during CRRT and the secondary outcome was filter life for the first filter of CRRT.

RESULTS

We included 101 patients (76 with NM, 25 with UFH). Among the 101 patients, use of NM tended to be associated with lower risk of bleeding complications (6.6% vs. 16%; odds ratio, 0.37; p = 0.16). Propensity score matching generated 30 patients with NM and 15 patients with UFH with well-balanced baseline characteristics. Among the propensity score-matched cohorts, use of NM was significantly associated with decreased risk of bleeding complications (3.3% vs. 27%; odds ratio, 0.09; p = 0.04). In multivariate logistic analysis using the inverse probability of treatment weighting for sensitive analysis, the use of NM was independently associated with reduced risk of bleeding complications (p = 0.02). The median filter life was not significantly different for patients with NM and patients with UFH (25.5 hours vs. 30.5 hours, p = 0.16).

CONCLUSIONS

In our retrospective analysis, the use of NM as an anticoagulant during CRRT was associated with decreased incidence of bleeding complications compared with the use of UFH.

Nafamostat Mesilate as an Anticoagulant During Continuous Renal Replacement Therapy in Patients With High Bleeding Risk: A Randomized Clinical Trial

Nafamostat mesilate (NM), a synthetic serine protease inhibitor, has been used increasingly as an anticoagulant during continuous renal replacement therapy (CRRT). However, there, are limited data from randomized studies on NM use in patients with a bleeding tendency. This prospective study evaluated the efficacy and safety of NM use during CRRT in patients with acute kidney injury (AKI) patients at high risk of bleeding.Patients with AKI at high risk of bleeding were randomized into the NM and no anticoagulant (NA) groups. The primary outcome was the treatment efficacy represented by the filter lifespan. Several parameters, including safety and patient survival rates at 30 and 90 days, were analyzed as secondary outcomes.Fifty-five patients were included in this study (NM group = 31, NA group = 24). The baseline characteristics did not significantly differ between the groups. The mean filter lifespan was significantly longer in the NM group than in the NA group (31.7 ± 24.1 versus 19.5 ± 14.9 hours; P = 0.035). The most common cause of filter failure was filter clotting, which was significantly more frequent in the NA group than in the NM group (59.6% versus 37.7%, P = 0.024). The Cox proportional hazards model showed a 42.2% longer filter lifespan in the NM group compared with the NA group (hazard ratio, 0.578; 95% confidence interval, 0.362-0.923; P = 0.022). There were no significant differences in the frequencies of transfusions and major bleeding between the groups. Patient survival rates at 30 and 90 days after CRRT initiation were comparable between the groups.Nafamostat mesilate is a safe and effective anticoagulant for CRRT and allows sufficient filter survival without increasing the risk of bleeding in critically ill patients with AKI and bleeding tendencies.

Ability of nafamostat mesilate to prolong filter patency during continuous renal replacement therapy in patients at high risk of bleeding: a randomized controlled study

Continuous renal replacement therapy (CRRT) is considered as an effective modality for renal replacement therapy in hemodynamically unstable patients within intensive care units (ICUs). However, the role of heparin anticoagulation, which is used to maintain circuit patency, is equivocal due to the risk of bleeding and morbidity. Among various alternative anticoagulants, nafamostat mesilate has been shown to be an effective anticoagulant in patients prone to bleeding. Hence, we conducted a prospective, randomized controlled study investigating the effect of nafamostat mesilate on mortality, CRRT filter life span and adverse events in patients with bleeding tendency. Seventy-three Patients were randomized into either the futhan or no-anticoagulation group. Thirty-six subjects in the futhan group received nafamostat mesilate, while thirty seven subjects in the no-anticoagulation group received no anticoagulants. Baseline characteristics and appropriate laboratory tests were taken from each group. The mortality between the two groups was not significantly different. Nevertheless, between the futhan group and the no-anticoagulation group, the overall number of filters used during CRRT (2.71 ± 2.12 vs. 4.50 ± 3.25; p = 0.042) and the number of filters changed due to clots per 24 hours (1.15 ± 0.81 vs. 1.74 ± 1.62; p = 0.040) were significantly different. When filter life span was subdivided into below and over 12 hours, the number of filters functioning over 12 hours was significantly higher in the futhan group than in the no-anticoagulation group (p = 0.037, odds ratio 1.84). There were no significant differences in transfusion, mortality, or survival between the two groups, and no adverse events related to nafamostat mesilate were noted. Hence, nafamostat mesilate may be used as an effective and safe anticoagulant, without increasing the risk of major bleeding complications, in patients prone to bleeding.

TRIAL REGISTRATION

Clinicaltrials.gov NCT01761994.