Rituximab in combination with cyclosporine and steroid pulse therapy for childhood-onset multidrug-resistant nephrotic syndrome: a multicenter single-arm clinical trial (JSKDC11 trial).

BACKGROUND: Only 80% of children with idiopathic nephrotic syndrome respond well to glucocorticoid therapy. Multidrug-resistant nephrotic syndrome (MRNS) is associated with a poor kidney prognosis. Several retrospective studies have identified rituximab as an effective treatment for MRNS; however, prospective studies are required to assess its efficacy and safety. METHODS: We conducted a multicenter, non-blinded, single-arm trial to investigate the efficacy and safety of rituximab in patients with childhood-onset MRNS who were resistant to cyclosporine and more than three courses of steroid pulse therapy. The enrolled patients received four 375 mg/m2 doses of rituximab in combination with baseline cyclosporine and steroid pulse therapy. The primary endpoint was a > 50% reduction in the urinary protein/creatinine ratio from baseline on day 169. Complete and partial remissions were also evaluated. RESULTS: Six patients with childhood-onset MRNS were enrolled. All patients were negative for pathogenic variants of podocyte-related genes. On day 169, five patients (83.3%) showed a > 50% reduction in the urinary protein/creatinine ratio, two patients showed partial remission, and two patients showed complete remission. No deaths occurred and severe adverse events occurred in two patients (infection in one patient and acute kidney injury in one patient). Three patients needed treatment for moderate-to-severe infection. CONCLUSIONS: The study treatment effectively reduced the urinary protein/creatinine ratio in patients with childhood-onset MRNS. The adverse events in this study were within the expected range; however, attention should be paid to the occurrence of infections.

Pharmacogenetic implementation for CYP2C19 and pharmacokinetics of voriconazole in children with malignancy or inborn errors of immunity.

BACKGROUND: Voriconazole pharmacokinetics (PK) are known to be affected by genetic polymorphisms of drug-metabolizing enzymes such as CYP2C19; however, such information is limited for the pediatric population. The primary aim of this study is to establish a voriconazole PK model incorporating CYP2C19 phenotypes in Japanese children with malignancy or inborn errors of immunity. METHODS: CYP2C19 genotypes were assessed by whole-genome genotyping and defined as follows: *17/*17: ultrarapid metabolizer (URM), *1/*17: rapid metabolizer (RM), *1/*1:normal metabolizer (NM), *1/*2, *1/*3, *2/*17:intermediate metabolizer (IM), and *2/*2, *2/*3, *3/*3: poor metabolizer (PM). Population PK analysis was performed. The voriconazole serum concentration profile was described by a two-compartment model with first-order absorption, mixed linear and nonlinear (Michaelis-Menten) elimination. RESULTS: Voriconazole concentration data were available from 60 patients with a median age of 5.3 years. The phenotypes predicted from CYP2C19 genotypes were RM in 1 (2 %), NM in 21 (35 %) patients, IM in 27 (45 %) patients, and PM in 11 (18 %) patients. Underlying diseases included 38 (63%) patients with hematological malignancy and 18 (30 %) patients with inborn errors of immunity. Among the CYP2C19 phenotypes, PM was predicted to show complete inhibition (the degree of Vmax inhibition [Vmax, inh] = 100 %; Vmax = 0). The estimated parameters of Vmax,inh were +0.8 higher in patients with gamma-glutamyl transpeptidase (γ-GTP) Grade 2 or higher and +2.7 higher when C-reactive protein (CRP) levels were 2.0 mg/dL or higher. CONCLUSION: CYP2C19 genetic polymorphisms, γ-GTP, and CRP affect Vmax,inh of voriconazole in children with malignancy or inborn errors of immunity.

Mycophenolate Mofetil after Rituximab for Childhood-Onset Complicated Frequently-Relapsing or Steroid-Dependent Nephrotic Syndrome.

BACKGROUND: Rituximab is the standard therapy for childhood-onset complicated frequently relapsing or steroid-dependent nephrotic syndrome (FRNS/SDNS). However, most patients redevelop FRNS/SDNS after peripheral B cell recovery. METHODS: We conducted a multicenter, randomized, double-blind, placebo-controlled trial to examine whether mycophenolate mofetil (MMF) administration after rituximab can prevent treatment failure (FRNS, SDNS, steroid resistance, or use of immunosuppressive agents or rituximab). In total, 39 patients (per group) were treated with rituximab, followed by either MMF or placebo until day 505 (treatment period). The primary outcome was time to treatment failure (TTF) throughout the treatment and follow-up periods (until day 505 for the last enrolled patient). RESULTS: TTFs were clinically but not statistically significantly longer among patients given MMF after rituximab than among patients receiving rituximab monotherapy (median, 784.0 versus 472.5 days, hazard ratio [HR], 0.59; 95% confidence interval [95% CI], 0.34 to 1.05, log-rank test: P=0.07). Because most patients in the MMF group presented with treatment failure after MMF discontinuation, we performed a post-hoc analysis limited to the treatment period and found that MMF after rituximab prolonged the TTF and decreased the risk of treatment failure by 80% (HR, 0.20; 95% CI, 0.08 to 0.50). Moreover, MMF after rituximab reduced the relapse rate and daily steroid dose during the treatment period by 74% and 57%, respectively. The frequency and severity of adverse events were similar in both groups. CONCLUSIONS: Administration of MMF after rituximab may sufficiently prevent the development of treatment failure and is well tolerated, although the relapse-preventing effect disappears after MMF discontinuation.

Population Pharmacokinetics and Pharmacodynamics of Meropenem in Critically Ill Pediatric Patients.

This study investigates the optimal meropenem (MEM) dosing regimen for critically ill pediatric patients, for which there is a lack of pharmacokinetic (PK) studies. We conducted a retrospective single-center PK and pharmacodynamic (PD) analysis of 34 pediatric intensive care unit patients who received MEM. Individual PK parameters were determined by a two-compartment analysis. The median (range) age and body weight were 1.4 (0.03 to 14.6) years and 8.9 (2.7 to 40.9) kg, respectively, and eight (23.5%) patients received continuous renal replacement therapy (CRRT), three of whom received extracorporeal membrane oxygenation. Renal function, the systemic inflammatory response syndrome (SIRS) score for the clearance (CL), and the use of CRRT for the central volume of distribution (Vc) were identified as significant covariates. The mean CL, Vc, and peripheral volume of distribution (Vp) were 0.45 liters/kg/h, 0.49 liters/kg, and 0.34 liters/kg, respectively. The mean population CL of MEM increased by 35% in patients with SIRS and Vc increased by 66% in patients on CRRT in the final model. Dosing simulations suggested that the standard dosing regimen provided insufficient PD exposures of a 100% free time above the MIC, and higher doses (40 to 80 mg/kg of body weight/dose every 8 h) with a prolonged 3-h infusion were required to ensure the appropriate PD exposures for patients with SIRS. Our PK model indicated that critically ill pediatric patients are at risk of subtherapeutic exposure under the standard dosing regimen of MEM. A larger, prospective investigation confirming the safety and efficacy of higher concentrations and prolonged infusion of MEM is necessary.

Live attenuated vaccines under immunosuppressive agents or biological agents: survey and clinical data from Japan.

Live attenuated vaccines are contraindicated for patients on immunosuppressive agents or biological agent, except for live attenuated varicella vaccine, although previous reports showed their effectiveness and safety. This study is the nationwide cross-sectional research about the current utilization of live attenuated vaccines for patients on immunosuppressive agents or biological agents in Japan. We sent questionnaires to pediatric centers and examined whether each institution offered live attenuated vaccines to patients with immunosuppressive agents or biological agents (institutional research). We also examined adverse events associated with live attenuated vaccines between 2013 and 2017 (patient research). In the institutional research, 46 out of 334 institutions (13.8%) administered live attenuated vaccines to patients receiving immunosuppressive agents. In contrast, only six out of 270 institutions (2.2%) administered live attenuated vaccines to patients receiving biological agents. However, 66.3% of physicians answered that patients receiving immunosuppressive agents should be immunized with live attenuated vaccines, and only 7.0% disagreed with them. In the patient research, data for 781 patients were collected. Vaccine-associated infections were observed in only two patients (0.3%), both of whom had varicella, although they recovered promptly. No life-threatening adverse events were noted. CONCLUSION: In pediatric centers, the demand for live attenuated vaccines in patients receiving immunosuppressive agents was high and most physicians think they should be immunized. Immunization with live attenuated vaccines appeared safe in patients receiving immunosuppressive agents, although further studies are needed for patients receiving biological agents What is known: • Live attenuated vaccines (LAV) are generally contraindicated for patients on immunosuppressive agents (IS) or biological agents (BA), except for live attenuated varicella vaccine, as immunocompromised patients are at greater risk for serious viral infection from the vaccine strains. • Viral infections, such as measles and varicella, cause serious complications in children receiving IS. • Several previous reports showed that LAV is relatively effective and safe for patients receiving IS. What is new: • In Japan, the demand for LAV in patients receiving IS was high, and most physicians hoped they should be immunized. • Vaccine-associated infection is rarely observed in patients with IS after LAV administration. • Immunization with LAV appeared safe in patients receiving IS. TRIAL REGISTRATION: University Hospital Medical Information Network (UMIN). TRIAL REGISTRATION NUMBER: UMIN000029176.Date of registration: 2017/09/19.

Principles of ethical consideration required for clinical research involving children.

Ethical considerations are more stringent in pediatric clinical research than in research targeting adults. However, in Japan, clear guidelines have yet to be presented on the necessary ethical considerations for clinical research involving children. The "Principles of Ethical Consideration Required for Clinical Research Involving Children" provide guiding principles for ethical considerations and the essential ways of thinking that all involved in clinical research on children need to understand in advance.

Population pharmacokinetic meta-analysis of individual data to design the first randomized efficacy trial of vancomycin in neonates and young infants.

OBJECTIVES: In the absence of consensus, the present meta-analysis was performed to determine an optimal dosing regimen of vancomycin for neonates. METHODS: A 'meta-model' with 4894 concentrations from 1631 neonates was built using NONMEM, and Monte Carlo simulations were performed to design an optimal intermittent infusion, aiming to reach a target AUC0-24 of 400 mg·h/L at steady-state in at least 80% of neonates. RESULTS: A two-compartment model best fitted the data. Current weight, postmenstrual age (PMA) and serum creatinine were the significant covariates for CL. After model validation, simulations showed that a loading dose (25 mg/kg) and a maintenance dose (15 mg/kg q12h if <35 weeks PMA and 15 mg/kg q8h if ≥35 weeks PMA) achieved the AUC0-24 target earlier than a standard 'Blue Book' dosage regimen in >89% of the treated patients. CONCLUSIONS: The results of a population meta-analysis of vancomycin data have been used to develop a new dosing regimen for neonatal use and to assist in the design of the model-based, multinational European trial, NeoVanc.

Lisinopril versus lisinopril and losartan for mild childhood IgA nephropathy: a randomized controlled trial (JSKDC01 study).

BACKGROUND: Persistent proteinuria seems to be a risk factor for progression of renal disease. Its reduction by angiotensin-converting inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs) is renoprotective. Our previous pilot study showed that 2-year lisinopril therapy is effective and safe for children with mild IgA nephropathy. When combined with ACEI and ARB, reported results are of greater decrease in proteinuria than monotherapy in chronic glomerulonephritis, including IgA nephropathy. To date, however, there have been no randomized controlled trials in children. METHODS: This is an open-label, multicenter, prospective, and randomized phase II controlled trial of 63 children with biopsy-proven proteinuric mild IgA nephropathy. We compared efficacy and safety between patients undergoing lisinopril monotherapy and patients undergoing combination therapy of lisinopril and losartan to determine better treatment for childhood proteinuric mild IgA nephropathy. RESULTS: There was no difference in proteinuria disappearance rate (primary endpoint) between the two groups (cumulative disappearance rate of proteinuria at 24 months: 89.3% vs 89% [combination vs monotherapy]). Moreover, there were no significant differences in side effects between the two groups. CONCLUSIONS: We propose lisinopril monotherapy as treatment for childhood proteinuric mild IgA nephropathy as there are no advantages of combination therapy. CLINICAL TRIAL REGISTRATION: Clinical trial registry, UMIN ID C000000006, https://www.umin.ac.jp .

Study protocol: multicenter double-blind, randomized, placebo-controlled trial of rituximab for the treatment of childhood-onset early-stage uncomplicated frequently relapsing or steroid-dependent nephrotic syndrome (JSKDC10 trial).

BACKGROUND: Eighty percent of children with idiopathic nephrotic syndrome respond well to steroid therapy, but up to 50% of patients with steroid-sensitive nephrotic syndrome exhibit frequently relapsing (FRNS) or steroid-dependent nephrotic syndrome (SDNS). Several studies identified the chimeric anti-CD20 monoclonal antibody rituximab as an effective treatment for patients with complicated FRNS/SDNS. Recent studies suggested that rituximab could also be a first-line treatment for early-stage uncomplicated FRNS/SDNS, although further studies are required to confirm its efficacy and safety. METHODS/DESIGN: We are conducting a multicenter, double-blind, randomized placebo controlled trial to investigate the efficacy and safety of rituximab for the treatment of childhood-onset early-stage uncomplicated FRNS/SDNS. Patients will be allocated to receive two 375 mg/m2 doses (maximum dose: 500 mg) of either rituximab or placebo. Investigators are permitted to request the disclosure of a subject's allocation code if he or she exhibits treatment failure. Additionally, if placebo-treated subjects display early relapse (a sign of treatment failure), they have the option to receive rituximab in an unblinded phase. The primary endpoint is relapse-free survival during the observation period. DISCUSSION: The results will provide important data on the use of rituximab for patients with uncomplicated FRNS/SDNS. In the future, rituximab treatment will enable most patients with uncomplicated FRNS/SDNS to discontinue or reduce steroid therapy without relapse, and it is possible that rituximab could represent an immunosuppressive therapy for these diseases. TRIAL REGISTRATION: This trial was prospectively registered to the JMACCT Clinical Trials Registry on September 6, 2018 (Trial ID: JMA-IIA00380 ).

Low-dose l-isoproterenol versus salbutamol in hospitalized pediatric patients with severe acute exacerbation of asthma: A double-blind, randomized controlled trial.

BACKGROUND: Although the guidelines in most countries do not recommend continuous inhalation of l-isoproterenol to treat pediatric patients with acute severe exacerbation of asthma, lower dose of l-isoproterenol has been widely used in Japan. To determine whether the efficacy of low-dose l-isoproterenol was superior to that of salbutamol, we conducted a double-blind, randomized controlled trial. METHODS: Hospitalized patients aged 1-17 years were eligible if they had severe asthma exacerbation defined by the modified pulmonary index score (MPIS). Patients were randomly assigned (1:1) to receive inhalation of l-isoproterenol (10 µg/kg/h) or salbutamol (500 µg/kg/h) for 12 hours via a large-volume nebulizer with oxygen. The primary outcome was the change in MPIS from baseline to 3 hours after starting inhalation. Trial registration number UMIN000001991. RESULTS: From December 2009 to October 2013, 83 patients (42 in the l-isoproterenol group and 41 in the salbutamol group) were enrolled into the study. Of these, one patient in the l-isoproterenol group did not receive the study drug and was excluded from the analysis. Compared with salbutamol, l-isoproterenol reduced MPIS more rapidly. Mean (SD) changes in MPIS at 3 hours were -2.9 (2.5) in the l-isoproterenol group and -0.9 (2.3) in the salbutamol group (difference -2.0, 95% confidence interval -3.1 to -0.9; P < 0.001). Adverse events occurred in 1 (2%) and 11 (27%) patients in the l-isoproterenol and salbutamol groups, respectively (P = 0.003). Hypokalemia and tachycardia occurred only in the salbutamol group. CONCLUSIONS: Low-dose l-isoproterenol has a more rapid effect with fewer adverse events than salbutamol.

Study protocol: mycophenolate mofetil as maintenance therapy after rituximab treatment for childhood-onset, complicated, frequently-relapsing nephrotic syndrome or steroid-dependent nephrotic syndrome: a multicenter double-blind, randomized, placebo-controlled trial (JSKDC07).

BACKGROUND: Idiopathic nephrotic syndrome (INS) is the most common chronic glomerular disease in children. Approximately 80-90% of patients with childhood INS have steroid-sensitive nephrotic syndrome (SSNS), and can obtain remission with steroid therapy, while the remainder have steroid-resistant nephrotic syndrome (SRNS). Furthermore, approximately 50% of children with SSNS develop frequently-relapsing nephrotic syndrome (FRNS) or steroid-dependent nephrotic syndrome (SDNS). Children with FRNS/SDNS are usually treated with immunosuppressive agents such as cyclosporine, cyclophosphamide, or mizoribine in Japan. However, 10-20% of children receiving immunosuppressive agents still show frequent relapse and/or steroid dependence during or after treatment, which is defined as complicated FRNS/SDNS. Furthermore, 30% of SRNS patients who obtain remission after additional treatments such as cyclosporine also turn out to be complicated FRNS/SDNS. For such complicated FRNS/SDNS patients, rituximab (RTX) is currently used; however, recurrence after RTX treatment also remains an open issue. Because long-term use of existing immunosuppressive drugs has limitations, development of a novel treatment for maintenance therapy after RTX is desirable. Mycophenolate mofetil (MMF) is an immunosuppressive drug with fewer side effects than cyclosporine or cyclophosphamide. Importantly, recent studies have reported the efficacy of MMF in children with nephrotic syndrome. METHODS: We conduct a multicenter, double-blind, randomized, placebo-controlled trial to evaluate the efficacy and safety of MMF after RTX therapy in children with complicated FRNS/SDNS. Patients are allocated to either RTX plus MMF treatment group, or RTX plus placebo treatment group. For the former group, MMF is administered at a dose of 1000-1200 mg/m2/day (maximum 2 g/day) twice daily for 17 months after RTX treatment. The primary endpoint is time-to-treatment failure (development of frequent relapses, steroid dependence or steroid resistance). DISCUSSION: The results will provide important data on the use of MMF as maintenance therapy after RTX to prevent complicated FRNS/SDNS patients from declining into treatment failure. In future, MMF in conjunction with RTX treatment may permit increased duration of remission in 'complicated' FRNS/SDNS cases. TRIAL REGISTRATION: This trial was prospectively registered to UMIN Clinical Trials Registry on June 23, 2014 (UMIN Trial ID: UMIN000014347 ).

Study protocol: high-dose mizoribine with prednisolone therapy in short-term relapsing steroid-sensitive nephrotic syndrome to prevent frequent relapse (JSKDC05 trial).

BACKGROUND: Eighty percent of children with steroid-sensitive nephrotic syndrome (SSNS) relapse within 2 years and 40-50% patients show frequently-relapsing nephrotic syndrome (FRNS). Patients showing a relapse within 6 months after initial remission are at high risk of FRNS. Since frequent prednisolone treatment for FRNS induces severe prednisolone side effects, development of a treatment to prevent patients from shifting to FRNS is desirable. Mizoribine is an immunosuppressive drug with fewer side effects than prednisolone. Recent studies reported the efficacy of high-dose mizoribine in children with FRNS. METHODS/DESIGN: We conduct a multicenter, open, randomized controlled trial to investigate the efficacy and safety of standard prednisolone plus high-dose mizoribine therapy in children with SSNS showing a relapse within 6 months after an initial remission. Patients are allocated to either standard prednisolone alone treatment group, or standard prednisolone plus high-dose mizoribine group. For the former group, mizoribine is administered at a dose of 10 mg/kg/day once daily and continued for 2 years. The primary endpoint is the duration to frequent relapse. DISCUSSION: The results provide important data on use of high-dose mizoribine to prevent SSNS patients from shifting to FRNS. Since blood concentrations of mizoribine have not been investigated in detail until now, there is a possibility that mizoribine is underestimated in favor of other immunosuppressive drugs. In future, high-dose mizoribine therapy may lead to prevention of relapse in children at high risk of FRNS, and to decreased total dose of prednisolone. TRIAL REGISTRATION: UMIN000005103 , (Prospectively registered 1st March 2011).

Proposal for the development of biologics in pediatric rheumatology.

In order to assess the development, approval and early introduction into clinical practice of biologics in the pediatric field, we herein describe the current status of the development to approval of biologics as anti-rheumatic agents for children in Japan, discuss the present problems and provide a proposal for the future. It has become apparent that the duration of the review period required for the preparation of clinical trials and Pharmaceuticals and Medical Devices Agency approval is clearly reduced compared with the past. Thus, it was speculated that a rate-limiting step in the process from development to approval was the duration of clinical trials from start to end. Hence, we focused on the following key words with regard to promotion of the development of biologics and their early practical use: "registry", "centralization", and "global cooperation", all of which are related to the reduction of duration of a clinical trial. In conclusion, to reduce the duration of a clinical trial, it is essential to complete a world-scale registry system by developing the registry system established by the Pediatric Rheumatology Association of Japan. The next step is then to carefully plan to participate in the international network using the world-scale registry system, and develop global cooperative trials in which we can ensure a sufficient number of entries from Japan.

Long-term outcome of childhood-onset complicated nephrotic syndrome after a multicenter, double-blind, randomized, placebo-controlled trial of rituximab.

BACKGROUND: Although rituximab effectively prevents relapses of complicated frequently relapsing nephrotic syndrome (FRNS) and steroid-dependent nephrotic syndrome (SDNS), data of long-term outcomes and safety are limited. METHODS: Fifty-one patients (age, 3-38 years) with childhood-onset complicated FRNS or SDNS, who received rituximab in investigator-initiated multicenter prospective trials were enrolled. Rituximab was administered at 375 mg/m2 once weekly for 4 weeks, and immunosuppressive agents were discontinued according to the study protocol. We investigated relapses, re-administration of immunosuppressive agents, additional rituximab treatment, body height, renal function, and late adverse events during the observation period. RESULTS: Forty-eight patients (94%) developed relapses during the observation period (median, 59 months) and the 50% relapse-free survival was 261 days. Thirty patients (59%) developed SDNS, 44 (86%) required re-administration of immunosuppressive agents, and 22 (43%) received additional rituximab treatment. All patients who were receiving immunosuppressive agents at rituximab treatment required either immunosuppressive agents or additional rituximab treatment. On the contrary, 5 of the 13 patients without immunosuppressive agents at rituximab treatment required neither immunosuppressive agents nor additional rituximab treatment and 3 of them did not develop relapse during observation period. Growth failure due to steroid toxicity did not progress and none of the patients developed chronic renal insufficiency. None of the patients suffered from rituximab-related late adverse events. CONCLUSIONS: As most patients suffer from relapses after B-cell recovery, long-term immunosuppressive agents or additional rituximab treatment is necessary. However, some patients who can discontinue immunosuppressive agents before rituximab treatment may achieve long-term remission after rituximab treatment without immunosuppressive agents.

A multicenter randomized trial indicates initial prednisolone treatment for childhood nephrotic syndrome for two months is not inferior to six-month treatment.

In this multicenter, open-label, randomized controlled trial, we determined whether 2-month prednisolone therapy for steroid-sensitive nephrotic syndrome was inferior or not to 6-month therapy despite significantly less steroid exposure. The primary end point was time from start of initial treatment to start of frequently relapsing nephrotic syndrome. The pre-specified non-inferiority margin was a hazard ratio of 1.3 with one-sided significance of 5%. We randomly assigned 255 children with an initial episode of steroid-sensitive nephrotic syndrome to either 2 - or 6-month treatment of which 246 were eligible for final analysis. The total prednisolone exposure counted both initial and relapse prednisolone treatment administered over 24 months. Median follow-up in months was 36.7 in the 2-month and 38.2 in the 6-month treatment group. Time to frequent relaps was similar in both groups; however, the median was reached only in the 6-month group (799 days). The hazard ratio was 0.86 (90% confidence interval, 0.64-1.16) and met the non-inferior margin. Time to first relapse was also similar in both groups: median day 242 (2-month) and 243 (6-month). Frequency and severity of adverse events were similar in both groups. Most adverse events were transient and occurred during initial or relapse therapy. Thus, 2 months of initial prednisolone therapy for steroid-sensitive nephrotic syndrome, despite less prednisolone exposure, is not inferior to 6 months of initial therapy in terms of time to onset of frequently relapsing nephrotic syndrome.

Rituximab for childhood-onset, complicated, frequently relapsing nephrotic syndrome or steroid-dependent nephrotic syndrome: a multicentre, double-blind, randomised, placebo-controlled trial.

BACKGROUND: Rituximab could be an effective treatment for childhood-onset, complicated, frequently relapsing nephrotic syndrome (FRNS) and steroid-dependent nephrotic syndrome (SDNS). We investigated the efficacy and safety of rituximab in patients with high disease activity. METHODS: We did a multicentre, double-blind, randomised, placebo-controlled trial at nine centres in Japan. We screened patients aged 2 years or older experiencing a relapse of FRNS or SDNS, which had originally been diagnosed as nephrotic syndrome when aged 1-18 years. Patients with complicated FRNS or SDNS who met all other criteria were eligible for inclusion after remission of the relapse at screening. We used a computer-generated sequence to randomly assign patients (1:1) to receive rituximab (375 mg/m(2)) or placebo once weekly for 4 weeks, with age, institution, treatment history, and the intervals between the previous three relapses as adjustment factors. Patients, guardians, caregivers, physicians, and individuals assessing outcomes were masked to assignments. All patients received standard steroid treatment for the relapse at screening and stopped taking immunosuppressive agents by 169 days after randomisation. Patients were followed up for 1 year. The primary endpoint was the relapse-free period. Safety endpoints were frequency and severity of adverse events. Patients who received their assigned intervention were included in analyses. This trial is registered with the University Hospital Medical Information Network clinical trials registry, number UMIN000001405. FINDINGS: Patients were centrally registered between Nov 13, 2008, and May 19, 2010. Of 52 patients who underwent randomisation, 48 received the assigned intervention (24 were given rituximab and 24 placebo). The median relapse-free period was significantly longer in the rituximab group (267 days, 95% CI 223-374) than in the placebo group (101 days, 70-155; hazard ratio: 0·27, 0·14-0·53; p<0·0001). Ten patients (42%) in the rituximab group and six (25%) in the placebo group had at least one serious adverse event (p=0·36). INTERPRETATION: Rituximab is an effective and safe treatment for childhood-onset, complicated FRNS and SDNS. FUNDING: Japanese Ministry of Health, Labour and Welfare.

Recommendations for HLA-B*15:02 and HLA-A*31:01 genetic testing to reduce the risk of carbamazepine-induced hypersensitivity reactions.

OBJECTIVE: To systematically review evidence on genetic risk factors for carbamazepine (CBZ)-induced hypersensitivity reactions (HSRs) and provide practice recommendations addressing the key questions: (1) Should genetic testing for HLA-B*15:02 and HLA-A*31:01 be performed in patients with an indication for CBZ therapy to reduce the occurrence of CBZ-induced HSRs? (2) Are there subgroups of patients who may benefit more from genetic testing for HLA-B*15:02 or HLA-A*31:01 compared to others? (3) How should patients with an indication for CBZ therapy be managed based on their genetic test results? METHODS: A systematic literature search was performed for HLA-B*15:02 and HLA-A*31:01 and their association with CBZ-induced HSRs. Evidence was critically appraised and clinical practice recommendations were developed based on expert group consensus. RESULTS: Patients carrying HLA-B*15:02 are at strongly increased risk for CBZ-induced Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) in populations where HLA-B*15:02 is common, but not CBZ-induced hypersensitivity syndrome (HSS) or maculopapular exanthema (MPE). HLA-B*15:02-positive patients with CBZ-SJS/TEN have been reported from Asian countries only, including China, Thailand, Malaysia, and India. HLA-B*15:02 is rare among Caucasians or Japanese; no HLA-B*15:02-positive patients with CBZ-SJS/TEN have been reported so far in these groups. HLA-A*31:01-positive patients are at increased risk for CBZ-induced HSS and MPE, and possibly SJS/TEN and acute generalized exanthematous pustulosis (AGEP). This association has been shown in Caucasian, Japanese, Korean, Chinese, and patients of mixed origin; however, HLA-A*31:01 is common in most ethnic groups. Not all patients carrying either risk variant develop an HSR, resulting in a relatively low positive predictive value of the genetic tests. SIGNIFICANCE: This review provides the latest update on genetic markers for CBZ HSRs, clinical practice recommendations as a basis for informed decision making regarding the use of HLA-B*15:02 and HLA-A*31:01 genetic testing in patients with an indication for CBZ therapy, and identifies knowledge gaps to guide future research. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.