Glomerular Endothelial Cell Receptor ADGRF5 and the Integrity of the Glomerular Filtration Barrier.

BACKGROUND: Glomerular endothelial cells are recognized to be important for maintaining the glomerular filtration barrier. ADGRF5, an adhesion G protein-coupled receptor, has been suggested to be involved in endothelial cell function. However, the role of ADGRF5 in the glomerular filtration barrier integrity remains elusive. METHODS: Cellular expression of ADGRF5 in mouse glomerulus was determined by histological analyses. The impact of ADGRF5 deletion on the glomerular morphology, kidney function, and glomerular endothelial gene/protein expression was then analyzed using ADGRF5 knockout (Adgrf5-/-) mice and human primary glomerular endothelial cells. RESULTS: ADGRF5 was specifically expressed in the capillary endothelial cells within the glomerulus. Adgrf5-/- mice developed albuminuria and impaired kidney function with morphological defects in the glomeruli, namely glomerular hypertrophy, glomerular basement membrane splitting and thickening, diaphragmed fenestration and detachment of the glomerular endothelial cells, and mesangial interposition. These defects were accompanied by the altered expression of genes responsible for glomerular basement membrane organization (type IV collagens and laminins) and Krüppel-like factor 2 (Klf2) in glomerular endothelial cells. Moreover, ADGRF5 knockdown decreased COL4A3 and COL4A4 expression and increased KLF2 expression in human primary glomerular endothelial cells. CONCLUSIONS: The loss of ADGRF5 resulted in altered gene expression in glomerular endothelial cells, and perturbed the structure and permselectivity of the glomerular filtration barrier.

Eculizumab for adult patients with atypical haemolytic-uraemic syndrome: full dataset analysis of Japanese post-marketing surveillance.

BACKGROUND: Eculizumab has been approved for atypical haemolytic-uraemic syndrome (aHUS) in Japan since 2013. Post-marketing surveillance enrolled patients with aHUS who received ≥ 1 dose of eculizumab to assess eculizumab safety and effectiveness. METHODS: We evaluated serious adverse events and effectiveness endpoints, i.e., haematologic normalization, a decrease of ≥ 25% in serum creatinine (sCr) levels, and complete thrombotic microangiopathy (TMA) response in adult patients with aHUS without other underlying diseases. In addition, the difference of baseline characteristics between patients who did and did not meet effectiveness endpoints was examined. RESULTS: In this safety and effectiveness analysis, 79 adult patients were included; median age was 54.0 years, median treatment duration was 30 weeks. Total exposure time of eculizumab was 75.51 patient-years, and 94 serious adverse events were reported in 39 patients. No unexpected safety signals were identified in this population. Mean platelet count, lactate dehydrogenase and estimated glomerular filtration rate significantly improved after 7 days of treatment. Complete TMA response, haematologic normalization and the improvement of sCr levels were met by 35.3%, 40.4% and 51.3% of patients, respectively. Median treatment duration was shorter in patients who did not achieve complete TMA response (6 weeks) than in patients who did (114 weeks). Multivariate analysis suggested that the time from the most recent TMA episode to start of eculizumab treatment was negatively associated with kidney function improvement. CONCLUSIONS: No unexpected safety signals of eculizumab were identified in Japanese patients with aHUS in a real-world setting. Renal outcomes were negatively associated with the time from the most recent TMA episode to the initiation of eculizumab treatment.

Nationwide epidemiological survey of polyarteritis nodosa in Japan in 2020.

Polyarteritis nodosa (PAN) is a systemic necrotizing vasculitis that predominantly affects medium-sized arteries. With advances in our understanding of the pathogenesis and classification of vasculitis, PAN and microscopic polyangiitis (MPA), a disease of anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV), were separated from the group of diseases previously diagnosed as periarteritis nodosa (PN) at the Chapel Hill Consensus Conference (CHCC) in 1994 (1).

Clinical practice guidelines of the Japan Research Committee of the Ministry of Health, Labour, and Welfare for Intractable Vasculitis for the management of microscopic polyangiitis and granulomatosis with polyangiitis: The 2023 update - secondary publication.

OBJECTIVE: To revise the 2017 clinical practice guidelines (CPG) for the management of microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA) to reflect advancements in the field. METHODS: Similar to the 2017 CPG, the Grading of Recommendations, Assessment, Development, and Evaluation system was adopted for this revision. The intended users of this CPG include patients diagnosed with MPA or GPA in Japan and their families and healthcare professionals, including specialists and non-specialists. Based on a scoping review, four clinical questions (CQs) of the 2017 guidelines were modified, and six new CQs were added. RESULTS: We suggest a combination of glucocorticoid and cyclophosphamide or rituximab for remission induction therapy. In cases where cyclophosphamide or rituximab is used, we suggest the use of avacopan over high-dose glucocorticoid. Furthermore, we suggest against the use of plasma exchange in addition to the standard treatment in severe cases of MPA/GPA. Finally, we suggest the use of glucocorticoid and rituximab over glucocorticoid and azathioprine for remission maintenance therapy. CONCLUSIONS: The recommendations have been updated based on patient preference, certainty of evidence, benefit and risk balance, and cost.

Evaluation of Ministry of Health, Labour and Welfare diagnostic criteria for antineutrophil cytoplasmic antibody-associated vasculitis compared to ACR/EULAR 2022 classification criteria.

OBJECTIVE: This study aimed to evaluate the Ministry of Health, Labour and Welfare (MHLW) diagnostic criteria for antineutrophil cytoplasmic antibody-associated vasculitis compared to the new American College of Rheumatology/European Alliance of Associations for Rheumatology 2022 criteria. METHODS: Two nationwide cohort studies were used, and participants were categorised as having eosinophilic granulomatosis with polyangiitis, granulomatosis with polyangiitis (GPA), or microscopic polyangiitis (MPA) according to the American College of Rheumatology/European Alliance of Associations for Rheumatology 2022 and MHLW criteria. RESULTS: Of the entire patient population, only 10 (2.1%) were unclassifiable according to the MHLW probable criteria, while a significant number of patients (71.3%) met at least two criteria. The MHLW probable criteria for MPA had some challenges in differentiating between MPA and eosinophilic granulomatosis with polyangiitis, and the same was true for MHLW probable criteria for GPA in differentiating MPA from GPA. Nevertheless, improved classification results were obtained when the MHLW probable criteria were applied in the order of eosinophilic granulomatosis with polyangiitis, MPA, and GPA. CONCLUSIONS: The application of MHLW criteria could categorise a substantial number of patients with antineutrophil cytoplasmic antibody-associated vasculitis into one of the three antineutrophil cytoplasmic antibody-associated vasculitis diseases. The classification was in accordance with the American College of Rheumatology/European Alliance of Associations for Rheumatology 2022 criteria when considering the order of application.

Examine the optimal multidisciplinary care teams for patients with chronic kidney disease from a nationwide cohort study.

Background: Multidisciplinary team-based integrated care (MDC) has been recommended for patients with chronic kidney disease (CKD). However, team-based specific structured care systems are not yet established. Therefore, we investigated the efficacy of MDC system and the optimal number of professionals that make up the team for maintaining kidney function and improving prognosis. Methods: This nationwide, multicenter, observational study included 2,957 Japanese patients with CKD who received MDC from 2015 to 2019. The patients were divided into four groups according to the number of professionals in the MDC team. Groups A, B, C, and D included nephrologists and one, two, three, and four or more other professionals, respectively. Changes in the annual decline in estimated glomerular filtration rate before and after MDC were evaluated. Cox regression was utilized to estimate the correlation between each group and all-cause mortality and the start of renal replacement therapy (RRT) for 7 years. Results: The change in eGFR significantly improved between before and at 6, 12, and 24 months after MDC in all groups (all p < 0.0001). Comparing group D to group A (reference), the hazard ratio (HR) for all-cause mortality and the start of the RRT was 0.60 (95% confidence interval, 0.48-0.73; p < 0.0001) after adjustment for multiple confounders. Lower HR in group D was confirmed in both diabetes and nondiabetes subgroups. Conclusion: An MDC team comprised of five or more professionals might be associated with improvements in mortality and kidney prognosis. Furthermore, MDC might be effective for treating CKD other than diabetes.

Inpatient multidisciplinary care can prevent deterioration of renal function in patients with chronic kidney disease: a nationwide cohort study.

Background: Multidisciplinary care is necessary to prevent worsening renal function and all-cause mortality in patients with chronic kidney disease (CKD) but has mostly been investigated in the outpatient setting. In this study, we evaluated the outcome of multidisciplinary care for CKD according to whether it was provided in an outpatient or inpatient setting. Methods: This nationwide, multicenter, retrospective, observational study included 2954 Japanese patients with CKD stage 3-5 who received multidisciplinary care in 2015-2019. Patients were divided into two groups: an inpatient group and an outpatient group, according to the delivery of multidisciplinary care. The primary composite endpoint was the initiation of renal replacement therapy (RRT) and all-cause mortality, and the secondary endpoints were the annual decline in the estimated glomerular filtration rate (ΔeGFR) and the changes in proteinuria between the two groups. Results: Multidisciplinary care was provided on an inpatient basis in 59.7% and on an outpatient basis in 40.3%. The mean number of health care professionals involved in multidisciplinary care was 4.5 in the inpatient group and 2.6 in the outpatient group (P < 0.0001). After adjustment for confounders, the hazard ratio of the primary composite endpoint was significantly lower in the inpatient group than in the outpatient group (0.71, 95% confidence interval 0.60-0.85, P = 0.0001). In both groups, the mean annual ΔeGFR was significantly improved, and proteinuria significantly decreased 24 months after the initiation of multidisciplinary care. Conclusion: Multidisciplinary care may significantly slow deterioration of eGFR and reduce proteinuria in patients with CKD and be more effective in terms of reducing initiation of RRT and all-cause mortality when provided on an inpatient basis.

Effectiveness and current status of multidisciplinary care for patients with chronic kidney disease in Japan: a nationwide multicenter cohort study.

BACKGROUND: Multidisciplinary care is well established in clinical practice, but its effectiveness in patients with chronic kidney disease (CKD) remains unclear. The aim of this study was to determine whether multidisciplinary care could help to avoid worsening kidney function in patients with CKD. METHODS: This nationwide study had a multicenter retrospective observational design and included 3015 Japanese patients with CKD stage 3-5 who received multidisciplinary care. We assessed the annual decrease in estimated glomerular filtration rate (ΔeGFR) and urinary protein in the 12 months before and 24 months after the start of multidisciplinary care. All-cause mortality and initiation of renal replacement therapy were investigated according to baseline characteristics. RESULTS: Most of the patients had CKD stage 3b or higher and a median eGFR of 23.5 mL/min/1.73 m2. The multidisciplinary care teams consisted of health care professionals from an average of four disciplines. ΔeGFR was significantly smaller at 6, 12, and 24 months after initiation of multidisciplinary care (all P < 0.0001), regardless of the primary cause of CKD and its stage when multidisciplinary intervention was started. Urinary protein level also decreased after initiation of multidisciplinary care. After a median follow-up of 2.9 years, 149 patients had died and 727 had started renal replacement therapy. CONCLUSION: Multidisciplinary care may significantly slow the decline in eGFR in patients with CKD and might be effective regardless of the primary disease, including in its earlier stages. Multidisciplinary care is recommended for patients with CKD stage 3-5. TRIAL REGISTRATION: UMIN00004999.

Validation of new ACR/EULAR 2022 classification criteria for anti-neutrophil cytoplasmic antibody-associated vasculitis.

OBJECTIVE: The objective of this study was to compare the American College of Rheumatology/European Alliance of Associations for Rheumatology 2022 criteria with the previous classification algorithm for anti-neutrophil cytoplasmic antibody-associated vasculitis. METHODS: We used data from two nationwide, prospective, inception cohort studies. The enrolled patients were classified as having eosinophilic granulomatosis with polyangiitis (EGPA), granulomatosis with polyangiitis (GPA), or microscopic polyangiitis (MPA) according to the new criteria; these criteria were compared with Watts' algorithm. RESULTS: Among 477 patients, 10.7%, 9.9%, and 75.6% were classified as having EGPA, GPA, and MPA, respectively; 6.1% were unclassifiable. Three patients met both the EGPA and MPA criteria, and eight patients met both the GPA and MPA criteria. Of 78 patients with GPA classified using Watts' algorithm, 27 (34.6%) patients were reclassified as having MPA. Ear, nose, and throat involvement was significantly less frequent in patients reclassified as having MPA than in those reclassified as having GPA. Of 73 patients unclassifiable using Watts' algorithm, 62 were reclassified as having MPA. All patients reclassified as having MPA were myeloperoxidase-anti-neutrophil cytoplasmic antibody positive, and 46 had interstitial lung disease. CONCLUSION: Although the American College of Rheumatology/European Alliance of Associations for Rheumatology 2022 criteria cause overlapping multiple criteria fulfilments in some patients, those items contribute to classifying unclassifiable patients using Watts' algorithm into MPA.

Efficacy and safety of avacopan in Japanese patients with antineutrophil cytoplasmic antibody-associated vasculitis: A subanalysis of a randomized Phase 3 study.

OBJECTIVES: This subgroup analysis of the randomized, double-blind, Phase 3 ADVOCATE study evaluated the efficacy and safety of avacopan compared with tapered prednisone in Japanese patients with antineutrophil cytoplasmic antibody-associated vasculitis. METHODS: Patients with microscopic polyangiitis (MPA) or granulomatosis with polyangiitis (GPA) received either avacopan 30 mg twice daily for 52 weeks plus prednisone-matching placebo or tapered prednisone over 20 weeks plus avacopan-matching placebo for 52 weeks. The two primary efficacy endpoints were clinical remission at Week 26 and sustained remission at Week 52. RESULTS: Compared with the overall population (N = 330), Japanese patients (N = 21) were older and had worse renal function, and a higher proportion were female and had MPA. The proportion of Japanese patients with clinical remission at Week 26 was 9/11 (81.8%) with avacopan vs. 7/10 (70.0%) with prednisone (overall population: 72.3% vs. 70.1%) and with sustained remission at Week 52 was 8/11 (72.7%) vs. 4/10 (40.0%), respectively (overall population: 65.7% vs. 54.9%). The safety profile of avacopan was similar in Japanese patients and the overall study population. CONCLUSIONS: The efficacy and safety of avacopan in Japanese patients with MPA or GPA were comparable to that observed in the overall ADVOCATE study population.

Nation-wide cohort study of remission induction therapy using rituximab in Japanese patients with antineutrophil cytoplasmic antibody-associated vasculitis: Effectiveness and safety in the first 6 months.

OBJECTIVES: The aim of this article is to evaluate the effectiveness and safety of rituximab (RTX) for microscopic polyangiitis and granulomatosis with polyangiitis in Japan. METHODS: In this prospective observational study, all patients with microscopic polyangiitis and granulomatosis with polyangiitis administered RTX were enrolled at each institution. During the observation period of 2 years, data up to 6 months were analysed. Cox proportional hazards analysis was used to assess the factors associated with an outcome. RESULTS: Of the 75 patients who received RTX for remission induction therapy, 53 achieved remission by the sixth month and 50 were in remission at the sixth month. During therapy, 38 serious adverse events were observed in 24 patients, 21 serious infections in 16 patients, and 9 patients died. No factors were associated with remission; however, there was a significant difference between patients with and without remission in serious adverse events (22.6% vs. 54.5%), serious infections (11.3% vs. 45.4%), and death (1.9% vs. 36.4%). The hazard ratio (95% confidence interval) for serious infection was 3.49 (1.29-9.74) for patients aged ≥ 75 years and 3.53 (1.31-9.53) for pulmonary complications. Four patients maintained remission for 6 months. CONCLUSIONS: The effectiveness and safety of RTX for microscopic polyangiitis and granulomatosis with polyangiitis for up to 6 months was demonstrated.

Upadacitinib for moderate-to-severe atopic dermatitis, in adults and adolescents 12 years and older: review of international and Japanese populations.

INTRODUCTION: Atopic dermatitis is one of the most prevalent chronic skin diseases. Topical therapies continue to be the mainstay of treatment but are limited by noncompliance and side-effects from inappropriate or long-term use. Systemic therapies including cyclosporine and dupilumab have been the treatments of choice for refractory cases. However, outcomes may remain less than satisfactory, and cyclosporine use is further limited by nephrotoxicity.Upadacitinib, an oral Janus kinase inhibitor, is widely used for treating rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis and has recently received approval for atopic dermatitis in the United States, Europe, Japan, and other countries. These approvals were based on results from several randomized controlled trials in which upadacitinib demonstrated better and faster response versus placebo or dupilumab. AREA COVERED: Therapies for atopic dermatitis are reviewed, with emphasis on drug profile, efficacy, and safety profile of upadacitinib for atopic dermatitis. In the review of the clinical trials, special focus is placed on efficacy in the Japanese population. EXPERT OPINION: Currently, there are several treatment options for atopic dermatitis refractory to topical therapies. However, appropriate utilization of Janus kinase inhibitors in clinical practice remains challenging, especially with regard to proper case selection, optimal timing, and appropriateness of use.

Systematic review and meta-analysis for 2023 clinical practice guidelines of the Japan Research Committee of the Ministry of Health, Labour, and Welfare for Intractable Vasculitis for the management of ANCA-associated vasculitis.

OBJECTIVES: The objective of this study is to provide evidence for the revision of clinical practice guidelines for the management of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis by the Japan Research Committee for Intractable Vasculitis. METHODS: PubMed, CENTRAL, and the Japan Medical Abstracts Society databases were searched for articles published between 2015 and 2020 to update the systematic review for existing clinical questions, while PubMed, CENTRAL, EMBASE, and the Japan Medical Abstracts Society were searched for articles published between 2000 and 2020 to conduct a systematic review for newly developed clinical questions. The certainty of evidence was assessed with the GRADE approach. RESULTS: For remission induction, when used in conjunction with cyclophosphamide or rituximab, reduced-dose glucocorticoid lowered the risk of serious adverse events compared to standard-dose glucocorticoid. Avacopan improved sustained remission at 12 months compared to high-dose glucocorticoid. Addition of plasma exchange to remission induction therapy did not reduce the risk of death, end-stage kidney disease, or relapse. For remission maintenance, rituximab reduced the risk of relapse compared to azathioprine. Long-term rituximab or azathioprine reduced the risk of relapse compared to short-term rituximab or azathioprine, respectively. CONCLUSIONS: This systematic review provided evidence required to develop the 2023 clinical practice guideline for the management of ANCA-associated vasculitis.

Concordance between practice and published evidence in the management of ANCA-associated vasculitis in Japan: A cross-sectional web-questionnaire survey.

OBJECTIVES: We conducted a descriptive study of the physicians' evidence-practice gap for adults covered by the 2017 clinical practice guidelines for the management of antineutrophil cytoplasmic antibody-associated vasculitis in Japan. METHODS: This web-based survey, conducted between January and February 2021, involved physicians who had treated at least five patients in the preceding year at a regional core hospital. The outcome was the physicians' experience in treating patients with microscopic polyangiitis or granulomatosis with polyangiitis [prevalence with 95% confidence intervals (CIs)], defined as treating at least 60% of their patients with the recommended therapy during the year. A modified Poisson regression analysis was performed to explore the factors associated with concordance. RESULTS: The 202 participants included 49 pulmonologists, 65 nephrologists, 61 rheumatologists, and other physicians. The concordance was 31.5% (95% CI, 25.1-38.5) of physicians who used cyclophosphamide or rituximab for the induction of remission. Rheumatology showed the highest concordance with published evidence (risk ratio = 2.4; 95% CI, 1.10-5.22, p = .03). CONCLUSIONS: These results suggest an evidence-practice gap, which varies substantially among subspecialties. Further studies and a new promotional initiative are necessary to close this gap in clinical practice.

Successful Kidney and Hematopoietic Stem Cell Transplantation for Malignant Lymphoma from Different Donors: A Case Report and Literature Review.

There are particularly few reports on kidney transplantation after hematopoietic stem cell transplantation (HSCT) for malignant lymphoma, and none of the cases reported a favorable outcome in patients who received kidney transplantation from a different donor to HSCT. In this report, we describe the first case of kidney transplantation from a different donor to HSCT with a successful outcome. Furthermore, we reviewed the previously reported cases. A 59-year-old female patient received an HSCT from her younger brother after chemotherapy for malignant lymphoma. After HSCT, she did not have graft-versus-host disease (GVHD) requiring maintenance treatment. The patient developed chronic kidney disease requiring kidney replacement therapy, probably due to drug toxicity or cardio-renal syndrome. At age 65, she underwent an ABO-compatible, HLA-A, -B, -DR 5/6 mismatched kidney transplantation from her husband. Immunosuppressive therapy with tacrolimus, mycophenolate mofetil, methylprednisolone, and basiliximab was administered. The patient had urinary tract infections at 7 days, 9 weeks, and 4 months after kidney transplantation, and cytomegalovirus antigenemia at 9 weeks after kidney transplantation, which improved with antibiotic and valganciclovir, respectively. When each infection occurred, we weakened immunosuppressive therapy. Four years after kidney transplantation, the patient is in good clinical condition with a serum creatinine of 1.2 mg/dL, without critical infection or malignancy. In this case, we believe that it was important to optimize the immunosuppressive therapy. In addition, from a review of previous cases, it seemed important that there was no GVHD requiring maintenance therapy in order to prevent excessive immunosuppression.

Clinical characteristics of patients with spondyloarthritis and inflammatory bowel disease versus inflammatory bowel disease-related arthritis.

The purpose of this study was to clarify the clinical characteristics of spondyloarthritis (SpA) patients with inflammatory bowel disease (IBD) compared to those without IBD. Furthermore, among patients with SpA and IBD, we aimed to clarify what clinical characteristics lead rheumatologists to diagnose "IBD-related arthritis." Utilizing SpA and psoriatic arthritis (PsA) patients' data from an international, cross-sectional, observational study, we analyzed information on demographics and disease characteristics, dichotomizing patients by IBD status. The presence or absence of IBD was determined based on data collection of treating rheumatologists. Patients with SpA (including PsA) and IBD were also categorized based on treating rheumatologists' definitive diagnosis in regard to SpA type, and compared by whether the patients had IBD-related arthritis or not. Among 4465 SpA patients, 287 (6.4%, 95%CI 5.7-7.2%) were identified with IBD. Compared to SpA patients without IBD, patients with SpA and IBD had a longer diagnostic delay (5.1 vs. 2.9 years, p < 0.001). In patients with SpA and IBD, 111 (38.7%, 95%CI 33.0-44.6%) were diagnosed with IBD-related arthritis. Multivariable analyses showed that HLA-B27 positivity [OR = 0.35, (95%CI 0.15-0.80)], psoriasis [OR = 0.14, (95%CI 0.04-0.50)], IBD as first symptom of SpA [OR = 3.32, (95%CI 1.84-6.01)], and need for IBD-specific treatment [OR = 5.41, (95%CI 2.02-14.50)] were independently associated with the definitive diagnosis of IBD-related arthritis. Collaboration with gastroenterologists is needed to shorten the diagnostic delay in patients with SpA and IBD. The recognition of the factors for the diagnosis of "IBD-related arthritis" may lead to the elucidation of the pathogenesis.

Plasmapheresis for systemic vasculitis.

Systemic vasculitides include a variety of, and numerous diseases. In 2012, the International CHAPEL HILL Consensus Conference (CHCC2012) led to a major reorganization of the classification of vasculitis, and this is still in wide use today. Although the results of plasmapheresis for individual diseases have been sometimes shown, there are few systematic reviews that discuss the effects along with vasculitis classification. Therefore, we will discuss the efficacy and the latest evidence for each vasculitis according to the CHCC 2012 classification in this review. This review provides a comprehensive overview of the estimation of plasmapheresis in each of the vasculitides, with a particular focus on small vasculitides, which have recently discussed frequently. For some time now, plasma exchange therapy (PEX) has been frequently used and is expected to be effective in some diseases, most of which are included in small vessel vasculitides. In particular, data showing efficacy have been accumulated for immune complex vasculitis, and the recommendation seems to be high. For instance, anti-GBM nephritis, concomitant use of PEX is essential and strongly recommended. On the other hand, for ANCA-related vasculitis among small vessel vasculitis, RCTs have recently shown negative results. In particular, the PEXIVAS trial statistically showed that PEX has no potential to reduce the mortality and renal death in AAV, but the ASFA, ACR, and KDIGO guidelines following this trial all regard PEX as salvage therapy or selective treatment for severe cases. As plasmapheresis is often performed in combination with other therapies, it is difficult to evaluate to clarify its efficacy on its own, and this predisposition may be pronounced in vasculitis, a rare disease. Although statistically significant differences are not apparent, the diseases that show a trend toward efficacy may possibly include treatment-sensitive subgroups. Further analysis is expected in the future.

Effectiveness of neutralizing antibody cocktail in hemodialysis patients: a case series of 20 patients treated with or without REGN-COV2.

The number of patients with SARS-CoV-2 infection continues to increase, and it has become a global pandemic. Although there is an urgent need to establish an effective treatment, the medication available for dialysis patients has been limited. An antibody cocktail containing two SARS-CoV-2-neutrarizing antibodies, REGN-COV2 has been granted special approval for COVID-19 in Japan, since July 2021, and this intravenous preparation can be used for dialysis patients. At our hospital, we had 22 hemodialysis patients with COVID-19, and five of them were treated with REGN-COV2. On admission, four of the five patients had moderate disease (pneumonia but O2 inhalation) and one patient had mild disease (not having pneumonia). The mean duration of hospitalization treated with REGN-COV2 was 10.2 ± 2.86 days (mean ± SD), which was less than half, compared to patients untreated of similar severity on admission (22.12 ± 15.5). The time to fever resolution was average 7 days, and no cases progressed to severe illness or death. Among these patients, no obvious adverse reactions were shown. Although more studies with a larger number of patients could be needed for a rigorous evaluation of the effect, our result suggests that REGN-COV2 may be safe and having the possibilities in preventing severe disease in hemodialysis patients. Given the difficulty in securing inpatient beds tend to be in short supply, the strategy combined with neutralizing antibody could be beneficial for end-stage kidney disease (ESKD) patients with hemodialysis who are at high risk of severe disease.