Effective treatment with rituximab for the maintenance of remission in frequently relapsing minimal change disease

[State-of-the-art paradigm of corticosteroid therapy for immune-mediated inflammatory kidney diseases]

Since 1950's corticosteroids (CS) have remained the cornerstone of immunosuppressive therapy for immune-mediated kidney diseases. However multiple adverse events, associated with the prolonged CS therapy, became the basis for the development of novel treatment approaches. Current evidence supports the implementation of the steroid-sparing regimens for the treatment of different types of glomerulonephritis. Randomised controlled trial PEXIVAS demonstrated the efficacy and safety of early steroid tapering, starting from the second week of therapy, in patients with ANCA-associated vasculitis with kidney involvement. Several trials showed the efficacy of oral prednisolone 0.3-0.5 mg/kg/daily as a part of multitarget therapy for severe proliferative lupus nephritis. A combination of calcineurin inhibitors and low-dose CS are effective for remission induction in membranous nephropathy, as well as the steroid-free rituximab regimen for the patients with moderate risk of disease progression. Medium dose CS showed promising effect in patients with IgA-nephropathy. Long-term high dose CS remain the standard-of-care for the treatment of minimal change disease and focal segmental glomerulosclerosis, however patients with steroid-dependent and relapsing disease tacrolimus and rituximab can help to achieve steroid-sparing effect. The role of CS pulse-therapy is currently debated, nevertheless it remains a compulsory treatment in several conditions. Thus, overall trend is directed towards the minimization of the maximal doses of CS and/or treatment duration. However, to implement this approach morphological verification of the diagnosis and personalized assessment of the potential risk and benefit are required.

[Diagnosis and treatment of Minimal Change Disease in adults-2023]

Minimal change disease is a glomerulopathy that clinically manifests as acute onset nephrotic syndrome. A diagnosis is made by renal biopsy, implying the absence of glomerular lesions on light microscopy but detection of extensive podocyte foot process effacement on electron miscroscopy. Considering the typically excellent response to immunosuppressive measures (especially to glucocorticoids), an autoimmune pathogenesis is assumed. Although general prognosis is overall beneficial, steroid-dependent, steroid-resistant and frequently-relapsing disease courses may complicate the management of these patients and necessitate the use of alternative immunosuppressive treatment strategies. Here, the Austrian Society of Nephrology (ÖGN) provides a consensus on how to best diagnose and manage adult patients with minimal change disease.

Age of Onset and Disease Course in Biopsy-Proven Minimal Change Disease: An Analysis From the Cure Glomerulonephropathy Network

RATIONALE & OBJECTIVE

Adolescent- and adult-onset minimal change disease (MCD) may have a clinical course distinct from childhood-onset disease. We characterized the course of children and adults with MCD in the Cure Glomerulonephropathy Network (CureGN) and assessed predictors of rituximab response.

STUDY DESIGN

Prospective, multicenter, observational study.

STUDY PARTICIPANTS

CureGN participants with proven MCD on biopsy.

EXPOSURE

Age at disease onset, initiation of renin-angiotensin-aldosterone system (RAAS) blockade, and immunosuppression including rituximab during the study period.

OUTCOME

Relapse and remission, change in estimated glomerular filtration rate (eGFR), and kidney failure.

ANALYTICAL APPROACH

Remission and relapse probabilities were estimated using Kaplan-Meier curves and gap time recurrent event models. Linear regression models were used for the outcome of change in eGFR. Cox proportional hazards models were used to estimate the association between rituximab administration and remission.

RESULTS

The study included 304 childhood- (≤12 years old), 49 adolescent- (13-17 years old), and 201 adult- (≥18 years) onset participants with 2.7-3.2 years of follow-up after enrollment. Children had a longer time to biopsy (238 vs 23 and 36 days in adolescent- and adult-onset participants, respectively; P<0.001) and were more likely to have received therapy before biopsy. Children were more likely to be treated with immunosuppression but not RAAS blockade. The rate of relapse was higher in childhood- versus adult-onset participants (HR, 1.69 [95% CI, 1.29-2.21]). The probability of remission was also higher in childhood-onset disease (HR, 1.33 [95%CI, 1.02-1.72]). In all groups eGFR loss was minimal. Children were more likely to remit after rituximab than those with adolescent- or adult-onset disease (adjusted HR, 2.1; P=0.003). Across all groups, glucocorticoid sensitivity was associated with a greater likelihood of achieving complete remission after rituximab (adjusted HR, 2.62; P=0.002).

LIMITATIONS

CureGN was limited to biopsy-proven disease. Comparisons of childhood to nonchildhood cases of MCD may be subject to selection bias, given that childhood cases who undergo a biopsy may be limited to patients who are least responsive to initial therapy.

CONCLUSIONS

Among patients with MCD who underwent kidney biopsy, there were differences in the course (relapse and remission) of childhood-onset compared with adolescent- and adult-onset disease, as well as rituximab response.

PLAIN-LANGUAGE SUMMARY

Minimal change disease is a biopsy diagnosis for nephrotic syndrome. It is diagnosed in childhood, adolescence, or adulthood. Patients and clinicians often have questions about what to expect in the disease course and how to plan therapies. We analyzed a group of patients followed longitudinally as part of the Cure Glomerulonephropathy Network (CureGN) and describe the differences in disease (relapse and remission) based on the age of onset. We also analyzed rituximab response. We found that those with childhood-onset disease had a higher rate of relapse but also have a higher probability of reaching remission when compared with adolescent- or adult-onset disease. Children and all steroid-responsive patients are more likely to achieve remission after rituximab.

Review of the Role of Rituximab in the Management of Adult Minimal Change Disease and Immune-Mediated Focal and Segmental Glomerulosclerosis

Background

Minimal change disease and primary FSGS are podocytopathies but are also immune-mediated diseases. Rituximab acts via multiple mechanisms by tilting the balance between autoreactive B and T cells in favor of regulatory B and T cells. The consequences are decreased production of cytokines, chemokines, and permeability factors by these cells. In the past decade, we have seen the discovery of autoantibodies mediating nephrotic syndrome (anti-annexin A2 antibody, anti-UCHL1 antibody, and anti-nephrin antibody), and rituximab decreases their production. Rituximab also binds to podocyte SMPDL3b and has direct podocyte actions.

Summary

Rituximab's role in managing these primary podocytopathies has been discussed in this brief review. Rituximab has been used extensively in children and adults with frequently relapsing and steroid-dependent nephrotic syndrome. However, rituximab is not very promising in adult steroid-resistant nephrotic syndrome. Although ofatumumab would cause prolonged B-cell depletion and is fully humanized, it is unclear if it is superior to rituximab in preventing relapse of nephrotic syndrome.

Key Messages

Rituximab therapy can induce prolonged remission in adults with frequently relapsing and steroid-dependent nephrotic syndrome. However, no good data exist on using rituximab in steroid-resistant nephrotic syndrome.

Case report: Successful outcome of treatment using rituximab in an adult patient with refractory minimal change disease and β-thalassemia complicating autoimmune hemolytic anemia

Minimal change disease (MCD) is one of the common causes of idiopathic nephrotic syndrome (INS), accounting for 10-20% of INS in adults. Glucocorticoids are the most commonly used and effective drugs in the treatment of MCD, but there is still a proportion of adult patients with MCD who are characterized by glucocorticoid resistance, glucocorticoid dependence, and frequent relapse, which are defined as refractory nephrotic syndrome. Glucocorticoid combination with immunosuppressants is frequently used in patients with refractory nephrotic syndrome, and patients concerned about adverse effects caused by long-term high-dose glucocorticoid therapy. Recent studies have suggested that Rituximab (RTX), a chimeric monoclonal antibody targeted against the pan-B-cell marker CD20, combined with a small or medium dose of glucocorticoid has a beneficial effect with less adverse effects on adult patients with refractory MCD. β-thalassemia is an inherited hemoglobulin disorder caused by the mutation of genes that encode β-globin and results in ineffective erythropoiesis. We here report a case of an adult patient with refractory MCD complicated with β-thalassemia minor accompanied by autoimmune hemolytic anemia (AIHA). MCD relapsed several times despite treatment using glucocorticoid combined with or without different immunosuppressive agent regimens. The β-thalassemia minor was caused by heterozygosity for a 4-base deletion mutation [codons 41/42 (-TTCT) BETA0] of the β-globin gene. After the administration of RTX, MCD achieved clinical complete remission, and the anemia due to mild β-thalassemia recovered to normal as well. The disease situation remained stable during 36 months of follow-up. These findings suggest that RTX may contribute to the improvement of refractory MCD and anemia in β-thalassemia minor accompanied by AIHA.

Rituximab Dosing in Glomerular Diseases: A Scoping Review

Purpose of Review

Rituximab is increasingly prescribed for glomerular diseases. However, the recently published Kidney Disease Improving Global Outcomes (KDIGO) 2021 Clinical Practice Guideline for the Management of Glomerular Diseases lacks details on recommended dosing regimens for most individual glomerular diseases. We performed this scoping review summarizing the evidence for rituximab dosing in glomerular disease.

Sources of Information

PubMed database.

Methods

The PubMed search methodology was developed with a medical librarian and performed by the first, with review by a second, author. Randomized controlled trials (RCTs) and prospective cohort studies (PCSs) examining rituximab efficacy and/or safety in antineutrophil cytoplasm antibody (ANCA)-associated vasculitis (AAV), membranous nephropathy (MN), lupus nephritis (LN), or podocytopathies (minimal change disease or focal segmental glomerulosclerosis [FSGS]) were included. Fifty-three studies (14 RCTs and 39 PCSs) were included.

Key Findings

We identified 16 different rituximab dosing regimens studied as induction therapy for one or more of the 5 glomerular diseases of interest. The most frequently studied rituximab induction regimens were 1000 mg as 2 doses 2 weeks apart (17 studies, 32%) and 4 doses of 375 mg/m2/week (18 studies, 33.9%). Twenty-six studies (49%) examined rituximab as monotherapy or in conjunction with corticosteroids alone, while the remaining studies examined rituximab as part of combination immunosuppression. Adapting treatment to achieve B-cell depletion, with frequent evaluation of disease-specific biomarkers, might prove the optimal approach to achieving and maintaining remission. Rituximab might also enable steroid minimization or avoidance.

Limitations

Restriction of the search to a single database and to studies published in the English language, and with an accompanying abstract, could have led to selection bias. While the search was limited to prospective observational studies and RCTs, no formal assessment of study quality was performed.

Steroids as treatment for glomerulonephritis: time for a rethink

Glucocorticoids have been a cornerstone of treatment for inflammatory and autoimmune kidney diseases for almost 70 years, yet it is fair to say, we still do not know how ‘best’ to use them. Significant adverse events are associated with their continued use, which contribute to premature patient mortality. Steroid avoidance or minimization is possible and has been tested in various glomerular diseases, as a result of novel agents or innovative regimens using established therapeutics. It is now time to seriously address our use of steroids and educate physicians on better ways of managing inflammatory kidney diseases.

Rituximab for Adults With Multi-Drug Resistant Focal Segmental Glomerulosclerosis: A Case Series and Review of the Literature

Background:

Adults with primary focal segmental glomerulosclerosis (FSGS) are frequently resistant to multiple immunosuppressive agents, which is associated with ongoing complications of nephrotic syndrome and a high risk of progression to end-stage renal disease (ESRD). Rituximab, a monoclonal antibody against the B cell CD20 antigen, has shown some preliminary evidence in treating nephrotic syndrome.

Objectives:

Describe the usage and the efficacy of rituximab for adults with FSGS in British Columbia (BC) (Canada) and perform a literature review of multi-immunosuppressive drug resistant FSGS in adult patients treated with rituximab to estimate the overall response rate.

Design:

Case series report and a literature review.

Patients:

For the case-series, all BC patients who received rituximab for a diagnosis of primary FSGS were included. The literature review included all cases of immunosuppressive-resistant FSGS patients treated with rituximab. We excluded transplant and pediatric patients in both groups.

Methods:

We describe all cases of adults with native-kidney FSGS resistant to conventional immunosuppressive medications from our provincial health database who were treated with rituximab from 2014 to 2018. A review of the existing literature was performed via PubMed, MEDLINE, and Embase using the following keywords: rituximab, focal segmental glomerulosclerosis, and FSGS up to August 2019.

Results:

We characterize four immunosuppressive-resistant FSGS patients who were treated with rituximab as part of our provincial program, all of whom showed a response to rituximab with a sustained remission. We found 29 specific cases in the literature of adults with native-kidney FSGS treated with rituximab after being resistant to other immunosuppressive medications, of whom 15 cases showed a response to rituximab. This has increased the total response rate from 15/29 (52%) to 19/33 (58%).

Limitations:

Literature on this topic is coming predominantly from case series. Prospective trials are needed to confirm efficacy, tolerability, and duration of remission.

Conclusions:

Due to the low number of currently reported cases and variable response rates, these four cases provide critical data to generate a more accurate understanding of the role of rituximab in adults with resistant FSGS. Adding these results to the confirmed literature cases of multiple-immunosuppressive-resistant FSGS patients treated with rituximab results in a total remission rate of 19/33 cases.

Rituximab Use for the Treatment of Childhood Nephrotic Syndrome by Canadian Pediatric Nephrologists: A National Survey

Background:

There is known practice variation in the treatment of frequently relapsing, steroid-dependent, and steroid-resistant nephrotic syndrome in children. Rituximab is an emerging therapy for difficult-to-treat nephrotic syndrome; however, there are no clear treatment guidelines. We therefore hypothesized that a wide variety of approaches to this therapy exist.

Objective:

To evaluate when and how rituximab is used for the treatment of childhood nephrotic syndrome in Canada.

Design and setting:

An online survey was used.

Participants:

Canadian pediatric nephrologists.

Methods:

A cross-sectional survey was distributed across Canada through the Canadian Association of Pediatric Nephrologists (CAPN) to evaluate rituximab treatment practices.

Results:

Of a total of 20 responses, 19 (95%) use rituximab in the treatment of nephrotic syndrome, usually as a third or fourth agent. For the number of rituximab doses, the majority (68%) uses 2 doses each time they use it. Eighteen respondents (90%) measure B cells when using this medication, mostly monthly (50%) or every 3 months (39%). Respondents were administered additional doses of rituximab prophylactically (74%) or at first relapse (47%). Long-term drug safety and drug funding were identified as the main barriers to rituximab use.

Limitations:

This survey represents the practice styles of physicians in a single country, and there is a nonresponse bias of 63%. Also, associations were not calculated.

Conclusions:

Among Canadian pediatric nephrologists, rituximab use for nephrotic syndrome appears to be increasing, but significant practice variations remain, including approaches to B-cell monitoring. It is reserved mostly for second-line and third-line use due to cost, funding issues, and residual uncertainty regarding long-term safety. Understanding these critical areas of practice uncertainty is a first step to optimize treatment of nephrotic syndrome in children.

The management of membranous nephropathy - an update

In the last decades several important advances have taken place in the understanding of the pathogenesis underlying membranous nephropathy, which have sparked renewed interest in its management. Four landmark trials in membranous nephropathy, and a fifth clinical trial-which was a pilot study-, have been published in the last years. The results from some of these trials have had a significant impact in the recommendations included in the 2021 Kidney Disease: Improving Global Outcomes (KDIGO) Guideline for the Management of Glomerular Diseases, which represent a significant step forward compared to the previous guideline in several aspects such as diagnosis, disease monitoring and treatment strategies. However, considering the rapidly evolving advances in the knowledge of membranous nephropathy and the recent publication of the STARMEN and RI-CYCLO trials, several recommendations contained in the guideline warrant updates. This manuscript provides a perspective of the Immunonephrology Working Group of the European Renal Association (ERA) regarding the management of membranous nephropathy in native kidneys of adult patients.

Extended infusion of rituximab combined with steroids is effective in inducing remission and reducing relapse in adult minimal change disease

Background

Minimal change disease is a common cause of nephrotic syndrome in adults. Higher relapse rate put patients at risk of steroids toxicity due to long-term exposure. Rituximab has been suggested to maintain long time remission and withdraw steroids and other immunosuppressants with fewer adverse events. However, optimal dose and dosing interval have not been explored.

Methods

Twenty-five patients were enrolled from 2017-10 to 2020-03 in Nanfang Hospital in China. Clinical and biological data were extracted from medical records and laboratory databases. Therapy composed of 375mg/m² rituximab once three weeks for 3 dose and corticosteroid was applied. Complete remission was defined as reduction of proteinuria to 0.3g/d. Remission rate, relapse rate, steroids used before and after rituximab therapy and adverse effects were documented at a mean time of 14.71 months.

Results

Twenty-two patients achieved complete remission for an average of 3.26 months and only 3 patients experienced one relapse respectively during the follow-up period. The mean remission maintenance time was 11.6 months, and was 5 months after steroids withdrawal. Steroids dose at last follow-up was 6.09mg/d, which was significantly reduced compared to 28.15mg/d before rituximab. Relapse rate before and after rituximab was 1.43 and 0.1, respectively. Only four minor adverse events were recorded.

Conclusions

Therapy consisted of 375mg/m² rituximab once three weeks for 3 dose combined with corticosteroid is effective in inducing remission in adult patients with minimal change disease. Both of the relapse rate and dose of steroids used are significantly decreased with fewer side effects.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02437-4.

Efficacy and safety of rituximab in adult frequent-relapsing or steroid-dependent minimal change disease or focal segmental glomerulosclerosis: a systematic review and meta-analysis

Background

The efficacy and safety of rituximab (RTX) in adult frequent-relapsing (FR) or steroid-dependent (SD) nephrotic syndrome (NS), including minimal change disease (MCD) or focal segmental glomerulosclerosis (FSGS), are still inconclusive.

Methods

We performed a systematic review and meta-analysis registered in  PROSPERO (CRD42019148102) by pooling data of cohort studies or case series on adult patients with difficult-to-treat NS. Steroid-resistant NS was excluded. The primary outcomes were the complete remission (CR) rate and the relapse rate. Partial remission (PR) rate, no response (NR) rate and adverse events were the secondary outcomes. A random-effects model was performed for all the outcomes.

Results

We included 21 studies involving 382 adult MCD/FSGS subjects with a median follow-up duration from 12 to 43 months. RTX treatment induced a pooled 84.2% CR rate [95% confidence interval (CI): 67.7–96.3%], while MCD patients had a high 91.6% CR rate and FSGS patients a moderate 43% CR rate. However, 27.4% (95% CI 20.7–34.5%) of the patients relapsed during the follow-up. The pooled PR and NR rates were 5.8% (95% CI 1.2–12.5%) and 5.2% (95% CI 0.0–15.0%), respectively. RTX was associated with trivial adverse events and good tolerance.

Conclusions

In summary, by pooling results of current pilot studies, RTX may be an effective and relatively safe alternative for most adult FR or SD MCD/FSGS to displace calcineurin inhibitors or prednisone in the hierarchy of treatment. More clinical trials comparing RTX with other immunosuppressants and concerning the long-term adverse events are needed.

Rituximab for the maintenance of minimal change nephropathy - A report of two pregnancies

Rituximab targets the CD20 antigen expressed on B-lymphocytes and is used to treat recurrent minimal change disease, but experience of its use in pregnancy is limited. We describe a 28-year-old Caucasian female, with recurrent nephrotic syndrome secondary to minimal change disease. She had failed to respond to non-teratogenic alternative therapies. The patient was successfully maintained in remission with rituximab during two consecutive pregnancies. Rituximab (1 g) was administered at 14⁺⁶ weeks 14 weeks and 6 days during Pregnancy 1 and 500 mg administered at 23⁺⁴ weeks 23 weeks and 4 days of Pregnancy 2. Rituximab had no apparent effect on infant B-cell development in either pregnancy, as neonatal lymphocyte titres were within normal range. There were no maternal complications in either pregnancy. Neither infant encountered infection-related complications. Although rituximab administration during pregnancy appeared safe, evidence of placental transfer is reported with neonatal B-cell depletion, thus alternatives with known safety profiles in pregnancy should be considered before rituximab administration.

Comparison of treatment options in adults with frequently relapsing or steroid-dependent minimal change disease

Background

Studies comparing all treatment options for frequently-relapsing/steroid-dependent (FR/SD) minimal change disease (MCD) in adults are lacking.

Methods

Medical records of 76 adults with FR/SD MCD who were treated with corticosteroids as the first-line therapy were reviewed. Treatment options were compared for the time to relapse, change of therapy and progression (relapse on full-dose treatment).

Results

Second-line treatments included rituximab (RTX; n = 13), mycophenolate mofetil (MMF; n = 12), calcineurin inhibitors (CNI; n = 26) and cyclophosphamide (CTX; n = 16). During the second-line treatments, 48 (71.6%) patients relapsed at median 17 (range 2–100)  months. The majority of relapses occurred during dose tapering or off drug. Twenty of 65 (30.8%) changed therapy after the first relapse. The median time to relapse after the second line was 66 versus 28 months in RTX versus non-RTX groups (P = 0.170). The median time to change of treatment was 66 and 44 months, respectively (P = 0.060). Last-line treatment options included RTX (n = 8), MMF (n = 4), CNI (n = 3) and CTX (n = 2). Seven (41.2%) patients had a relapse during the last-line treatment at median 39 (range 5–112)  months. The median time to relapse was 48 versus 34 months in the RTX versus non-RTX groups (P = 0.727). One patient in the RTX group died presumably of heart failure. No major adverse event was observed. During the median follow-up of 81 (range 9–355)  months, no patients developed end-stage renal disease.

Conclusions

Relapse is frequent in MCD in adults. Patients treated with RTX may be less likely to require a change of therapy and more likely to come off immunosuppressive drugs.

Efficacy of repeat-dose rituximab maintenance therapy for minimal change disease in adults

BACKGROUND

Rituximab (RTX) has been reported to effectively treat minimal change disease (MCD) in adults. However, the efficacy of RTX as maintenance therapy, especially in older patients, remains unclear. This study aimed to evaluate the efficacy of repeat-dose RTX maintenance therapy regardless of age.

METHODS

We retrospectively reviewed the clinical courses of 13 biopsy-proven adult MCD patients receiving RTX and evaluated the relapse rate, concomitant steroid and immunosuppressant use, relationship between B-cell depletion time and relapse, and adverse events.

RESULTS

Mean patient age at start of RTX therapy was 51.5 ± 20.1 years. Each RTX induction consisted of a single 375 mg/m² dose. One patient received two RTX doses with a 1-year interval. The remaining 12 patients received RTX at 6-month intervals up to four times after RTX introduction. The median observation period was 28 (16-60) months after RTX induction, median relapse frequency was significantly decreased from 0.83 (0.18-1.92) to 0 (0-0.71) times/year (P < 0.001), and median prednisolone dose was reduced from 25 (5-40) mg to 2.5 (0-10) mg (P < 0.001). CD19-positive B cells remained depleted during RTX administration in 6-month intervals. No serious adverse events were observed after RTX administration.

CONCLUSIONS

Repeat-dose RTX as maintenance therapy efficiently prevented recurrence and was well tolerated in adult MCD patients including older. This regimen has the potential to maintain prolonged remission. Future studies in larger cohorts are needed to identify the optimal dose and frequency and evaluate the long-term effectiveness and safety of this regimen.

Rituximab in maintaining remission in adults with podocytopathy

Rituximab is currently used after the conventional agents have failed in the management of steroid-dependent (SD)/ steroid-resistant (SR) podocytopathies and have a safer toxicity profile. We report 53 adults with podocytopathies who were managed effectively with CD19-targeted rituximab therapy.

METHODS

This was a prospective study carried out at a tertiary care centre in India between January 2014 and June 2019. Adults between 16 and 60 years with SD, frequently relapsing (FR), and SR nephrotic syndrome (NS) due to podocytopathy received rituximab in a CD19-targeted approach.

PRIMARY OUTCOME

Percentage of patients who were in remission at 6 and 12 months. Secondary outcome: Percentage of patients in remission at the last follow-up, rituximab dose and adverse events of rituximab therapy.

RESULTS

Fifty-three adults with SD/FR/SR NS received CD19-targeted rituximab. The median age at the time of first rituximab injection was 30.09 ± 13.21 (16.53) years. At the time of first rituximab infusion, all patients were in remission with steroids and/or calcineurin inhibitors (CNIs). Fifty (94.33%) patients were in remission at the end of 6 and 12 months and the last follow-up (median: 36 months). The mean total dose of rituximab at 1 year was 788.7 ± 128.1 (6 001 100) mg. At last follow-up (median 36 months), 42 (79%) patients did not require any additional CNI or steroids therapy. No serious adverse events to rituximab were noted.

CONCLUSION

CD19-targeted rituximab therapy is safe and efficacious in the management of SD/SR adult podocytopathy. Also, rituximab is effective in maintaining remission in treatment naïve adult SD or FR podocytopathy.

Rituximab therapy for focal segmental glomerulosclerosis and minimal change disease in adults: a systematic review and meta-analysis

Background

Use of rituximab (RTX) for focal segmental glomerulosclerosis (FSGS) and minimal change disease (MCD) is widely described in children. Clinical evidence in adults is limited. The objective of this study was to determine the treatment outcomes of RTX in adults with FSGS and MCD.

Methods

Ovid MEDLINE, SCOPUS, and Cochrane Database of Systematic Reviews were searched up to September 2019. Out of 699 studies, we included 16 studies describing the treatment outcomes of rituximab in adult patients with FSGS or MCD. Results were reported in remission rate and relapse rate. Serious adverse events were also reported.

Results

A total of 16 studies were included in our review and analysis. All studies were observational studies and included a total of 221 patients (23.1% FSGS, 76.9% MCD). Mean follow-up duration was 26.3 ± 12.8 months. From the analysis of five studies with FSGS patients (n = 51), the overall remission rate and relapse rate of RTX therapy was 53.6% (95% CI, 15.8–87.6%) and 47.3% (95% CI, 25.4–70.2%), respectively. Complete remission occurred in 42.9%. In contrast, from the analysis of 11 studies with MCD patients (n = 170), the overall remission rate and relapse rate of RTX therapy was 80.3% (95% CI, 68.5–88.5%) and 35.9% (95% CI, 25.1–48.4), respectively. Complete remission occurred in 74.7%. Subgroup analyses showed that overall remission and relapse were not different after adjusted for study year and RTX dose for both FSGS and MCD. Incidence of serious adverse events was 0.092 events/year.

Conclusions

Rituximab may be considered as an additional treatment to the standard therapy for adult patients with FSGS and MCD. Remissions and relapses are similar between FSGS and MCD. Serious adverse effects of rituximab were uncommon. We encourage further randomized controlled trials to confirm the efficacy of rituximab therapy in these patients.

Rituximab use in adult glomerulopathies and its rationale

Glomerulopathies are one of the leading causes of end-stage renal disease. In the last years, clinical research has made significant contributions to the understanding of such conditions. Recently, rituximab (RTX) has appeared as a reasonably safe treatment. The Kidney Disease: Improving Global Outcomes guidelines (KDIGO) recommended RTX only as initial treatment in antineutrophil cytoplasm antibody associated vasculitis (AAV) and in non-responders patients with lupus nephritis (LN), but these guidelines have not been updated since 2012. Nowadays, RTX seems to be at least as effective as other immunosuppressive regimens in idiopathic membranous nephropathy (IMN). In minimal-change disease, (MCD) this drug might allow a long-lasting remission period in steroid-dependent or frequently relapsing patients. Preliminary results support the use of RTX in patients with pure membranous LN and immunoglobulin-mediated membranoproliferative glomerulonephritis (MPGN), but not in patients with class III/IV LN or complement-mediated MPGN. No conclusion can be drawn in idiopathic focal segmental glomerulosclerosis (FSGS) and anti-glomerular basement membrane antibody glomerulonephritis (anti-GBM GN) because studies are small, heterogeneous, and scarce. Lastly, immunosuppression including RTX is not particularly useful in IgA nephropathy. This review presents the general background, outcomes, and safety for RTX treatment in different glomerulopathies. In this regard, we describe randomized controlled trials (RCTs) performed in adults, whenever possible. A literature search was performed using clinicaltrials.gov and PubMed.

Rituximab use in adult glomerulopathies and its rationale

Glomerulopathies are one of the leading causes of end-stage renal disease. In the last years, clinical research has made significant contributions to the understanding of such conditions. Recently, rituximab (RTX) has appeared as a reasonably safe treatment. The Kidney Disease: Improving Global Outcomes guidelines (KDIGO) recommended RTX only as initial treatment in antineutrophil cytoplasm antibody associated vasculitis (AAV) and in non-responders patients with lupus nephritis (LN), but these guidelines have not been updated since 2012. Nowadays, RTX seems to be at least as effective as other immunosuppressive regimens in idiopathic membranous nephropathy (IMN). In minimal-change disease, (MCD) this drug might allow a long-lasting remission period in steroid-dependent or frequently relapsing patients. Preliminary results support the use of RTX in patients with pure membranous LN and immunoglobulin-mediated membranoproliferative glomerulonephritis (MPGN), but not in patients with class III/IV LN or complement-mediated MPGN. No conclusion can be drawn in idiopathic focal segmental glomerulosclerosis (FSGS) and anti-glomerular basement membrane antibody glomerulonephritis (anti-GBM GN) because studies are small, heterogeneous, and scarce. Lastly, immunosuppression including RTX is not particularly useful in IgA nephropathy. This review presents the general background, outcomes, and safety for RTX treatment in different glomerulopathies. In this regard, we describe randomized controlled trials (RCTs) performed in adults, whenever possible. A literature search was performed using clinicaltrials.gov and PubMed.

Low-dose rituximab is no less effective for nephrotic syndrome measured by 12-month outcome

OBJECTIVE

Rituximab is an effective treatment for children with steroid dependent or frequently relapsing nephrotic syndrome. The optimum dosing schedule for rituximab has not been established. We hypothesized that a single low dose of 375 mg/m² would have comparable outcomes to higher doses in reducing the frequency of relapse and time to B cell reconstitution.

METHODS

We conducted a multicenter retrospective observational cohort study of children with steroid-sensitive frequently relapsing nephrotic syndrome. Data were extracted from clinical records including the dates of diagnosis, treatment, relapses, the use of concomitant immunosuppression, and lymphocyte subset profiling. Patients treated earlier received variable doses of rituximab, although typically two doses of 750 mg/m². Later, patients received the current regimen of a single dose of 375 mg/m². The primary outcome was an absence of clinically confirmed relapse 12 months following rituximab administration. Secondary outcomes were median time to relapse, probability of being relapse-free at 6 and 24 months and time to reconstitution of CD19⁺ B cells.

RESULTS

Sixty patients received 143 courses of rituximab. Seven different dosing regimen strategies were used, ranging between 375 and 750 mg/m² per dose, with administration of 1-4 doses. There was no significant difference in event-free survival at 12 months between dosing strategies. The median time to reconstitution of B cells was not significantly different between groups.

CONCLUSIONS

Use of a single low-dose regimen of rituximab in the management of frequently relapsing nephrotic syndrome does not affect the probability of relapse at 12 months or time to B cell reconstitution compared to a conventional higher dose.

Increased PD-1+CD154+ Tfh cells are possibly the most important functional subset of PD-1+ T follicular helper cells in adult patients with minimal change disease

T follicular helper (Tfh) cells, especially programmed cell death protein 1 (PD-1)⁺ Tfh cells, exert important functions in the normal immune response. The purpose of this study was to determine the frequency of different subsets of PD-1⁺ Tfh cells and their functional effects in adult patients with minimal change disease (MCD). The frequencies of circulating PD-1⁺, PD-1⁺CD154⁺, and PD-1⁺interleukin (IL)-21⁺ Tfh cells, and CD38⁺CD19⁺ and CD38⁺CD19⁺CD40⁺ B cells, as well as serum IL-2, IL-4, IL-17A, IL-6, IL-21, and interferon (IFN)-γ were significantly increased in the MCD patients compared with the healthy controls (HCs) (P < 0.05). However, no significant difference was found in PD-1⁺BCL-6⁺ or PD-1⁺ICOS⁺ Tfh cells. Furthermore, the percentages of PD-1⁺ Tfh and PD-1⁺CD154⁺ Tfh cells were negatively correlated with the estimated glomerular filtration rate (eGFR), but positively correlated with the 24-h urinary protein concentration and serum IL-21 level. The percentages of PD-1⁺ Tfh and PD-1⁺CD154⁺ Tfh cells were positively correlated with the percentages of CD38⁺ plasma cells and active CD38⁺CD40⁺ plasma cells, respectively. After an 8-12-week treatment with prednisolone, the percentages of PD-1⁺, PD-1⁺CD154⁺, and PD-1⁺IL-21⁺ Tfh cells as well as the serum level of IL-21 were significantly reduced; in contrast, the serum levels of IL-4 and IL-10 were increased (P < 0.05). We conclude that increased PD-1⁺CD154⁺ Tfh cells are possibly the most important functional subset of PD-1⁺ Tfh cells and may contribute towards the pathogenesis of MCD.

The Evolving Role of Rituximab in Adult Minimal Change Glomerulopathy

BACKGROUND

Minimal-change glomerulopathy is defined histologically by the presence of normal glomeruli on light microscopy and diffuse podocyte effacement on electron microscopy. Although effective in children, corticosteroid treatment in adults is more variable and time to response can be prolonged. Data to support rituximab use in adults with corticosteroid-dependent or resistant minimal-change glomerulopathy are limited. Here, we describe the clinical course of adults with corticosteroid-dependent or -resistant minimal-change glomerulopathy who received rituximab.

METHODS

Demographic and clinical data were collected and analyzed from all adult patients with native kidney, biopsy-proven, minimal-change glomerulopathy who were administered rituximab between 2009 and 2014 and cared for at the UNC Kidney Center.

RESULTS

Ten patients with corticosteroid-resistant (n = 5) or corticosteroid-dependent (n = 5) idiopathic minimal-change glomerulopathy were treated with rituximab between 2009 and 2014. Rituximab treatment induced remission in all 10 patients with a median time to remission of 2 months. The median time from rituximab to corticosteroid discontinuation was 3.5 months. The median remission time was 29 months and follow-up time was 39.5 months. No serious adverse events attributable to rituximab were observed.

CONCLUSION

Rituximab induced remission in all patients with corticosteroid-dependent or -resistant minimal-change glomerulopathy, and may hold great therapeutic potential with good efficacy and minimal toxicity. Mounting evidence implies that a well-conducted randomized controlled clinical trial using rituximab in adults with minimal-change glomerulopathy in both corticosteroid-resistant and corticosteroid-dependent patients is warranted.

Effective treatment with rituximab for the maintenance of remission in frequently relapsing minimal change disease

AIM

Treatment of frequently relapsing or steroid-dependent minimal change disease (MCD) in children and adults remains challenging. Glucocorticoids and/or other immunosuppressive agents are the mainstay of treatment, but patients often experience toxicity from prolonged exposure and may either become treatment dependent and/or resistant. Increasing evidence suggests that rituximab (RTX) can be a useful alternative to standard immunosuppression and allow withdrawal of maintenance immunosuppressants; however, data on optimal treatment regimens, long-term efficacy and safety are still limited.

METHODS

We undertook a prospective study of RTX to allow immunosuppression minimization in 15 young adults with frequently relapsing or steroid-dependent, biopsy-proven MCD. All patients were in remission at the start of treatment and on a calcineurin inhibitor. Two doses of RTX (1 gr) were given 6 months apart. A subset of patients also received an additional dose 12 months later, in order to examine the benefit of re-treatment. Biochemical and clinical parameters were monitored over an extended follow-up period of up to 43 months.

RESULTS

Median steroid-free survival after RTX was 25 months (range 4-34). Mean relapse frequency decreased from 2.60 ± 0.28 to 0.4 ± 0.19 (P < 0.001) after RTX. Seven relapses occurred, five of which (71%) when CD19 counts were greater than 100 µ. Immunoglobulin levels remained unchanged, and no major side effects were observed throughout the follow-up period.

CONCLUSIONS

Rituximab therapy is effective at maintaining prolonged steroid-free remission and reducing relapse frequency in this group of patients. Our study lends further support for the role of RTX in the treatment of patients with frequently relapsing or steroid-dependent MCD.