anti-CD20 Monoclonal Antibody Research Articles

Isatuximab, Bortezomib, Lenalidomide, and Dexamethasone for Multiple Myeloma

BackgroundBortezomib, lenalidomide, and dexamethasone (VRd) is a preferred first-line treatment option for patients with newly diagnosed multiple myeloma. Whether the addition of the anti-CD38 monoclonal antibody isatuximab to the VRd regimen would reduce the risk of disease progression or death among patients ineligible to undergo transplantation is unclear.MethodsIn an international, open-label, phase 3 trial, we randomly assigned, in a 3:2 ratio, patients 18 to 80 years of age with newly diagnosed multiple myeloma who were ineligible to undergo transplantation to receive either isatuximab plus VRd or VRd alone. The primary efficacy end point was progression-free survival. Key secondary end points included a complete response or better and minimal residual disease (MRD)–negative status in patients with a complete response.ResultsA total of 446 patients underwent randomization. At a median follow-up of 59.7 months, the estimated progression-free survival at 60 months was 63.2% in the isatuximab-VRd group, as compared with 45.2% in the VRd group (hazard ratio for disease progression or death, 0.60; 98.5% confidence interval, 0.41 to 0.88; P<0.001). The percentage of patients with a complete response or better was significantly higher in the isatuximab-VRd group than in the VRd group (74.7% vs. 64.1%, P=0.01), as was the percentage of patients with MRD-negative status and a complete response (55.5% vs. 40.9%, P=0.003). No new safety signals were observed with the isatuximab-VRd regimen. The incidence of serious adverse events during treatment and the incidence of adverse events leading to discontinuation were similar in the two groups.ConclusionsIsatuximab-VRd was more effective than VRd as initial therapy in patients 18 to 80 years of age with newly diagnosed multiple myeloma who were ineligible to undergo transplantation. (Funded by Sanofi and a Cancer Center Support Grant; IMROZ ClinicalTrials.gov number, NCT03319667.)

The early and rapid response to daratumumab in children with chronic refractory immune thrombocytopenia from a referral single centre of China.

Chronic refractory primary immune thrombocytopenia (CRITP) is currently defined as refractory to multiple therapeutic of second-line agents with or without splenectomy, faced with the threat of severe bleeding and challenging to obtain effective treatment. Although stable and effective drug therapy is needed, it is tough to find one. Daratumumab (Dara), an anti-CD38 monoclonal antibody presented the target cloned plasma cells in multiple myeloma, has also been reported to be effective in refractory autoimmune cytopenia in some case or series reports and ongoing clinical trials for adult patients with CRITP. Here, we report the early and durable response of Dara combination with avatrombopag in three CRITP patients (2 male and 1 female aged 12, 5 and 7 years, respectively) in our centre, with a follow-up period of more than 25 weeks. Before Dara, the duration of immune thrombocytopenia was 9, 1.4 and 4 years, respectively, a baseline platelet count of 4, 6, 9 × 109/L, the bleeding score was all above level 2 and the number of previous drugs was >3. The time to response (R: Plt ≥30 × 109/L with at least a twofold increase in the baseline count) of Dara was on Day 45, 6 and 4 and achieved complete response (CR: Plt ≥100 × 109/L) on Day 51, 6 and 8, the sustained response (SR: Plt >30 × 109/L following Dara at ≥75% of the platelet count assessment at follow-up end-point since the patient achieved response) was 48, 175 and 204 days with the follow-up time of 39.1, 25.9 and 29.7 weeks. The bleeding score decreased from grade 3 to grade 0 during follow-up. No significant treatment-related adverse events were found during follow-up. Dara combination with avatrombopag may be a safe and efficacious therapy for children with CRITP, but it needs to be further explored.

Navigating High-Risk and Ultrahigh-Risk Multiple Myeloma: Challenges and Emerging Strategies.

Despite significant improvement in the outcomes of patients with newly diagnosed multiple myeloma (NDMM) with novel therapies, there is still an underserved high-risk (HR) population that experiences early disease progression and death. With the median survival crossing 10 years, we defined ultrahigh-risk (uHR)MM as MM leading to death within 24-36 months of diagnosis and HRMM as MM leading to death within 36-60 months. Several features have emerged as markers of uHRMM: the co-occurrence of two or more high-risk cytogenetic abnormalities, extramedullary disease, plasma cell leukemia and a high-risk gene expression profiling signature. The heterogeneous risk definition across trials, the few trials available designed for HR patients, and the small HR subgroups in all-comers trials make it difficult to generate recommendations with high levels of evidence. Nevertheless, regardless of treatment administered, several studies consistently showed that achieving and maintaining measurable residual disease negativity is now considered the main factor able to mitigate the adverse prognosis related to baseline features. For fit patients with HR transplant-eligible (TE) NDMM, quadruplet induction/consolidation treatment with anti-CD38 monoclonal antibodies, immunomodulatory agents, proteasome inhibitors and dexamethasone, and autologous stem-cell transplant and maintenance with, if available, at least a doublet combination could be considered the option of choice. For non-TE NDMM, considering the recent data generated and carefully reviewing those upcoming, quadruplet treatment consisting of anti-CD38 monoclonal antibodies, immunomodulatory agents, proteasome inhibitors, and dexamethasone should also be considered. Future trials integrating BCMA-directed novel generation immunotherapies hold great potential for further advancing the treatment landscape in all NDMM patients with HR disease.

Rapid reduction of free light chains and improvement in renal outcomes in patients with newly diagnosed multiple myeloma admitted with acute kidney injury with daratumumab-based therapy and without plasmapheresis.

7525 Background: Cast nephropathy is the most common cause of acute kidney injury (AKI) in patients with multiple myeloma (MM), where light chain accumulation in the distal nephron leads to obstruction and injury of the distal and collecting tubules. A prompt reversal of renal injury is paramount to improve outcomes. Daratumumab (dara), an anti-CD38 monoclonal antibody, has significant clinical efficacy in MM. We report the effects of early initiation of dara-based therapy on sFLC reduction and renal recovery in pts admitted with a new diagnosis of MM and AKI. Methods: Between April 2016 and Dec 2023, pts admitted with newly diagnosed MM (NDMM) with AKI (sCr ≥2 mg/dL and/or eGFR &lt;30 mL/min/1.73 m2 by CKD-EPI) and involved sFLC ≥500 mg/L who started dara-based therapy were identified and retrospectively reviewed. We studied pts who started treatment ≤14 days of presentation. Outcomes included sFLC kinetics and renal outcomes per IMWG criteria at 3 months. Results: We identified 20 NDMM pts. Median age was 65 (range 44-87). Median peak sCr at admission was 6.5 mg/dL (range 3.1-17.8) with median eGFR of 8 mL/min/1.73 m2 (range 2-16). Nine pts started hemodialysis (HD). The median peak sFLC at diagnosis was 6603 mg/L (range 1839-26,023). Initial dara regimens included cyclophosphamide, bortezomib, and dexamethasone in 11 pts (55%) and with bortezomib and dexamethasone in 9 pts (45%). Median time between presentation and dara start was 3 days (range 0-10). No pts underwent plasmapheresis. Within 1 cycle of therapy, all 20 pts achieved sFLC reduction ≥50% at a median of 3 days (95% CI, 3-7 days). Median time to sFLC ≤500 mg/L was 13 days (95% CI, 9-33 days), and this was in 15 out of 16 pts (94%) assessable for response after 1 cycle of treatment. At 3 m, the overall renal response (≥minor response) was 85% (N=17), with complete, partial, and minor responses in 50% (N=10), 10% (N=2), and 25% (N=5), respectively. Twelve pts (60%) recovered renal function with eGFR ≥40 mL/min. Of 9 pts who required HD, 4 and 6 pts were free of HD at 3 m and 12 m, respectively. Two pts on HD died within 3 m (age 86, from aspiration pneumonia; age 87, from progressive disease); and 1 continued on HD at 12 months. Fourteen pts (70%) later added lenalidomide, and 3 pts (15%) underwent autologous stem cell transplant. The IMWG ORR was 100% with VGPR 90%. With a median follow up of 25 m, median PFS was 47 m (95% CI 12-not reached) and 2-year OS was 84% (95% CI 68-100%). Conclusions: This is the largest reported cohort of NDMM pts hospitalized with AKI treated with dara-based induction therapy. Treatment with dara combinations shows rapid and deep reductions in sFLC, improving renal recovery outcomes. These findings highlight the efficacy of early use of dara in pts with MM-induced AKI and provide an approach without plasmapheresis.

Ultra-low-dose rituximab is effective for the treatment of patients with minimal change disease - A retrospective study

Background purposeRituximab (RTX),an anti-CD20 monoclonal antibody can effectively treat minimal change disease (MCD),with low toxicity and a reduced steroid dosage. The optimal dosage of RTX for treating MCD remains unclear. This study aimed to investigate the efficacy of an ultra-low-dose regimen of RTX (100 mg per week for 4 weeks) for treating MCD. MethodsWe retrospectively analyzed clinical data from 31 patients with MCD who received RTX. Seventeen patients received ultra-low-dose RTX (ULD-RTX) therapy, and 14 patients received standard-dose RTX (SD-RTX) therapy (500 mg weekly for 4 weeks). All patients were followed up for at least 6 months. ResultsBoth groups showed significant increases in the serum albumin levels and notable decreases in the urinary protein levels in the 1st and 6th months after RTX therapy. There were no significant differences in the plasma albumin or urinary protein levels between the groups (p > 0.05). B-cell depletion was observed in all patients after 1 month of RTX administration. At 6 months after RTX treatment, the remission rate was 93% in the SD-RTX group and 88% in the ULD-RTX group (p > 0.05). The ULD-RTX therapy incurred lower costs than did the SD-RTX therapy. One patient in the SD-RTX group developed community-acquired pneumonia. ConclusionUltra-low-dose RTX is effective at inducing remission in patients with MCD at a lower cost.

EPCORE FL-2: Phase 3 trial of epcoritamab with rituximab and lenalidomide (R2) vs chemoimmunotherapy or R2 in previously untreated follicular lymphoma.

TPS7084 Background: Follicular lymphoma (FL) is the most common indolent non-Hodgkin lymphoma. Most patients with advanced-stage FL in need of systemic therapy are treated with an anti-CD20 monoclonal antibody (eg, rituximab [R] or obinutuzumab [G]) with cyclophosphamide, doxorubicin, vincristine, and prednisone [CHOP] or bendamustine [benda]). Recent studies have shown R plus lenalidomide (R2) is a potent FL treatment in the 1L and relapsed or refractory (R/R) settings and is a promising backbone for combination therapies. Epcoritamab, a subcutaneous CD3xCD20 bispecific antibody, received breakthrough therapy designation by the FDA for R/R FL after ≥2 lines of systemic therapy. In the phase 1/2 trial (NCT04663347), epcoritamab plus R2 demonstrated high complete response (CR) rates in the 1L and R/R settings. The objective of this trial is to evaluate the safety and efficacy of 1L epcoritamab plus R2 vs CIT in patients with FL. Methods: EPCORE FL-2 (NCT06191744) is a global, randomized, open-label phase 3 trial. Eligible adult patients must have CD20+ histologically confirmed classic FL (previously grade 1–3A), stage III or IV disease (or bulky stage II), and in need of systemic treatment by meeting GELF criteria. Approximately 1080 patients will be randomized to 3 treatment arms (Table). Patients achieving CR or PR upon 6 cycles will move to epcoritamab on day 1 of cycles 7–12 (28-day cycles) and 13–21 (56-day cycles). After 120 weeks of treatment, patients will be followed for progression and survival. Dual primary endpoints will be CR rate at 30 months and progression-free survival in arm A vs arm B. Key secondary efficacy endpoints include overall survival, minimal residual disease negativity, and changes in patient-reported outcomes on the physical functioning scale of the European Organization for Research and Treatment of Cancer Quality of Life-C30 Questionnaire from baseline to week 25. Safety endpoints include incidence and severity of adverse events (AEs), including AEs of special interest (cytokine release syndrome, immune effector cell–associated neurotoxicity syndrome, and clinical tumor lysis syndrome). The study is open for enrollment. Clinical trial information: NCT06191744 . [Table: see text]

Quadruplet therapy for transplant-eligible newly diagnosed multiple myeloma (TENDMM): A systematic review and meta-analysis.

e19534 Background: Immunomodulatory drugs, proteasome inhibitors plus dexamethasone are the standard triplet induction regimen for TENDMM. We analyzed the efficacy of adding either anti-CD38 monoclonal antibodies (mAbs) or anti-SLAMF7 antibody to the triplet therapy. Methods: Ovid MEDLINE, EMBASE and published abstracts were systematically searched from each database’s inception through 01-31-2024 to identify II/III trials assessing quadruplet therapy versus triplet therapy in TENDMM patients. Hazard ratios (HR) for progression-free survival (PFS) and overall survival (OS), odds ratios (OR) for overall response rates (ORR), measurable residual disease (MRD) negativity rate (with sensitivity of 10 -5) and grade 3 or higher treatment-related adverse events (G≥3 TRAE) were summarized using random effects meta-analysis via inverse variance approach. Additional subgroup analyses based on the cytogenetic risk were performed. P-value of interaction (Pint ) &lt; 0.1 was pre-specified as statistically significant for the difference between the two groups. Results: 3806 studies were screened and seven trials were included with a total of 3546 patients. Four trials (2303 patients) assessed the addition of anti-CD-38 mAbs and three (1243 patients) assessed anti-SLAMF7 mAb, elotuzumab to the triplet regimen. Quadruplet therapy significantly improved PFS as compared to triplet (HR: 0.63; 95% CI: 0.43-0.92), and the PFS benefit was also observed in standard risk group (HR 0.5; 95% CI 0.2-0.9); however, results were insignificant for high-risk group (HR 0.8; 95% CI 0.62-1.93). No significant OS benefit was observed (HR: 0.79; 95% CI 0.49–1.26); however, data for three trials (CASSIOPEIA, DSMM XVII, PERSEUS) is immature, with longer-term follow-up ongoing. Quadruplet therapy showed significant results for very good partial response or better (OR: 1.7; 95% CI 1.2-2.36), stringent complete response (OR: 1.74; 95% CI 1.27-2.07) and complete response or better (OR: 1.91; 95% CI 1.19-3.06). MRD rate shows benefit with quadruplet therapy (OR: 2.59; 95% CI 2.22-3.01). Improved MRD rate was also observed for high-risk (OR 2.13; 95% CI 1.4-3.2) and standard-risk group (OR 2.58; 95% CI 1.68-3.94). Secondary analysis for efficacy of anti-CD38 mAbs showed benefit for PFS (HR: 0.44; 95% CI: 0.35-0.56), ORR (OR: 1.77;95% CI: 1.02-3.06), and MRD (OR: 2.98; 95% CI 1.8-4.8). G ≥3 TRAE did not significantly differ between the groups (OR: 1.05; 95% CI 0.97-1.12). However, quadruplet therapy showed significant risk of infection (OR: 1.2; 95% 1.05-1.35) and thrombocytopenia (OR: 1.41; 95% CI 1.24-1.59). Conclusions: Quadruplet therapy improved PFS, ORR, and MRD rates compared to triplet regimen and has demonstrated promising benefits to be considered the new standard of care for TENDMM patients.

Graves-PCD: protocol for a randomised, dose-finding, adaptive trial of the plasma cell-depleting agent daratumumab in severe Graves’ disease

IntroductionSevere Graves’ disease is a life-changing condition with poor outcomes from currently available treatments. It is caused by directly pathogenic thyroid-stimulating hormone receptor-stimulating antibodies (TRAb), which are secreted from plasma...

Long-term survival outcomes in patients with relapsed/refractory large B-cell lymphoma after treatment of relma-cel: 4-year follow-up in RELIANCE study.

e19001 Background: RELIANCE study (NCT04089215) demonstrated the efficacy and safety of relma-cel, a CD19-targeted chimeric antigen receptor T-cell product, in patients with heavily pre-treated relapsed/refractory large B-cell lymphoma (r/r LBCL). We previously reported efficacy of relma-cel, noting objective response rate (ORR) in 77.59% of patients (CRR 53.45%), 2-year progression-free survival (PFS) rate and overall survival (OS) rate were 38.8% and 69.3%, respectively. Herein, we aimed to update the long-term survival results for 4-year follow-up (FU). Methods: Study design was previously published. Eligible patients were adults with histologically confirmed r/r LBCL and had failed at least two prior lines of therapy, including an anti-CD20 monoclonal antibody and an anthracycline-based regimen. Patients were enrolled at 10 clinical sites in China and underwent lymphodepletion prior to receiving relma-cel at a single dose of 100 × 106 (n=27) or 150 × 106 (n=32) CAR+ T cells. The primary endpoint was ORR at 3-month, as assessed by investigators. Secondary endpoints were duration of response (DOR), PFS, OS and safety profiles. For this abstract, we collected the survival status and updated the survival outcomes. Results: From Nov 2017 to Dec 2019, a total of 68 patients were enrolled, and 59 received relma-cel infusion. Among 58 evaluable efficacy patients with 2-year FU, 31 achieved CR (CR group), 14 achieved PR (PR group) and 13 had no response (Non-responder group). As of Dec 18, 2023, with 48.1 months (95% CI, 37.75 to 49.38) of median FU, 25 patients were still alive, 18 were died (5 deaths in CR group, 5 in PR group and 8 in Non-responder group), and 15 patients were censored due to lost to FU including 7 lost within 2 years and 8 after 2 years. The median OS were not reached (NR), and 1-year and 2-year OS rate were reported previously. The update estimated landmark OS rates were 69.3% at 3-year and 66.7% at 4-year. The OS rates of CR group at each year were numerically higher than those of PR group and Non-responder group (87.1% v.s. 59.3% v.s. 30.8% at 3-year and 82.5% v.s. 59.3% v.s. 30.8% at 4-year; Table). Conclusions: Four-year FU results in RELIANCE Study suggested that, although heavily pretreated, the patients who had response, especially who achieved CR, may experience greater survival benefits, from relma-cel therapy. Clinical trial information: NCT04089215 . [Table: see text]

Phase 3 study results of isatuximab, bortezomib, lenalidomide, and dexamethasone (Isa-VRd) versus VRd for transplant-ineligible patients with newly diagnosed multiple myeloma (IMROZ).

7500 Background: The first line of treatment (tx) is important for patients (pts) with newly diagnosed multiple myeloma (NDMM) as pts may not have a chance for subsequent therapy. VRd is currently a standard of care (SOC) in NDMM. Isa is an approved anti-CD38 monoclonal antibody (mAb) inducing myeloma cell death through multiple mechanisms. In the Phase 3 IMROZ study (NCT03319667), we investigate the efficacy and safety of Isa-VRd vs VRd in transplant-ineligible NDMM pts. Methods: IMROZ is a global, prospective, randomized, open-label study done at 102 study sites in 21 countries. Included pts had active, measurable NDMM not considered for transplant due to elderly age or comorbidities. Pts aged ≥80 were excluded. Pts were randomized 3:2 and stratified by age, R-ISS stage and China vs non-China, to receive Isa-VRd or VRd. Isa-VRd arm pts received Isa (10 mg/kg IV); both arms received V (1.3 mg/m2 SC), R (25 mg PO) and d (20 mg IV/PO). The primary endpoint was progression-free survival (PFS). Key secondary endpoints were complete response (CR), minimal residual disease negativity (MRD-) (10-5 by NGS) in pts with CR, very good partial response or better and overall survival. Adverse events (AEs) and laboratory parameters were graded with NCI CTCAE v4.03. Results: 446 pts (265 Isa-VRd, 181 VRd) were randomized; pt characteristics were well balanced. At data cutoff (26 Sep 2023), 125 (47.2%) and 44 (24.3%) pts in Isa-VRd and VRd arms were still on tx, respectively. Median (mdn) tx duration was 53.2 (Isa-VRd) vs 31.3 (VRd) mo; addition of Isa did not significantly affect relative dose intensity of VRd. At mdn follow-up of 59.7 mo, mdn PFS was not reached (Isa-VRd) vs 54.3 mo (VRd); HR 0.596 (98.5% CI 0.406–0.876), log-rank p=0.0005. From the current trend, projected Isa-VRd mdn PFS will reach ~90 mo. PFS benefit was consistent across subgroups and maintained through subsequent line of therapy (PFS2 HR 0.697; 95% CI: 0.51-0.952). Isa-VRd led to deep and sustained responses and was well-tolerated (Table). Exposure-adjusted Grade 5 TEAE rate was 0.03 (Isa-VRd) vs 0.02 (VRd). Conclusions: IMROZ is the first Phase 3 study of an anti-CD38 mAb with SOC VRd in this pt population to show a significantly reduced risk of progression or death by 40.4% vs VRd while providing deep and sustained responses. The safety profile was consistent with addition of Isa to VRd. Numerical differences in TEAEs are largely explained by longer exposure in the Isa-VRd arm. These results support Isa-VRd as a potential new SOC in pts not intended for transplant. Clinical trial information: NCT03319667 . [Table: see text]

The IPTA Nashville consensus conference on post-transplant lymphoproliferative disorders after solid organ transplantation in children: IV-consensus guidelines for the management of post-transplant lymphoproliferative disorders in children and adolescents.

The International Pediatric Transplant Association convened an expert consensus conference to assess current evidence and develop recommendations for various aspects of care relating to post-transplant lymphoproliferative disorders (PTLD) after pediatric solid organ transplantation. This report addresses the outcomes of deliberations by the PTLD Management Working Group. A strong recommendation was made for reduction in immunosuppression as the first step in management. Similarly, strong recommendations were made for the use of the anti-CD20 monoclonal antibody (rituximab) as was the case for chemotherapy in selected scenarios. In some scenarios, there is uncoupling of the strength of the recommendations from the available evidence in situations where such evidence is lacking but collective clinical experiences drive decision-making. Of note, there are no large, randomized phase III trials of any treatment for PTLD in the pediatric age group. Current gaps and future research priorities are highlighted.

Monitoring Response and Resistance to Treatment in Chronic Lymphocytic Leukemia.

The recent evolution in chronic lymphocytic leukemia (CLL) targeted therapies led to a progressive change in the way clinicians manage the goals of treatment and evaluate the response to treatment in respect to the paradigm of the chemoimmunotherapy era. Continuous therapies with BTK inhibitors achieve prolonged and sustained control of the disease. On the other hand, venetoclax and anti-CD20 monoclonal antibodies or, more recently, ibrutinib plus venetoclax combinations, given for a fixed duration, achieve undetectable measurable residual disease (uMRD) in the vast majority of patients. On these grounds, a time-limited MRD-driven strategy, a previously unexplored scenario in CLL, is being attempted. On the other side of the spectrum, novel genetic and non-genetic mechanisms of resistance to targeted treatments are emerging. Here we review the response assessment criteria, the evolution and clinical application of MRD analysis and the mechanisms of resistance according to the novel treatment strategies within clinical trials. The extent to which this novel evidence will translate in the real-life management of CLL patients remains an open issue to be addressed.

Ibrutinib followed by ofatumumab consolidation in previously untreated patients with chronic lymphocytic leukemia (CLL): GELLC-7 trial from the Spanish group of CLL (GELLC)

BTK inhibitors have been concurrently administered with anti-CD20 monoclonal antibodies (mAbs) in chronic lymphocytic leukemia (CLL). However, the optimal regimen for combining these two drugs remains pending. This multi-center phase 2 study aimed to analyze whether consolidation with ofatumumab improved the response in patients with CLL receiving front-line treatment with ibrutinib. Patients received 12 cycles of ibrutinib monotherapy. Those who achieved CR after this induction were maintained on ibrutinib. Conversely, those who did not attain CR continued with ibrutinib in addition to a consolidation, which involved 7 doses of ofatumumab. The primary objective was the complete response (CR) rate at cycle 20. This study is registered within the EU Clinical Trials Register (EudraCT 2016-004937-26). Between September 8, 2017, and May 21, 2018, 84 patients (median age, 69 years) were included. After completion of 12 cycles of ibrutinib (n=80), 4 patients (5%) were in CR, 67 (84%) in partial response (PR), and 6 patients (7%) had a PR with lymphocytosis (PRL). After consolidation with ofatumumab, 20 patients improved the response from PR to CR and 6 patients with PRL obtained a PR. Seventy-one patients (85%) completed 20 cycles of treatment, with a CR rate of 24/71 (34%). According to the intention-to-treat analysis at cycle 20, the ORR was 69/84 (82.2%), with a CRR of 24/84 (28.6%). Progression-free survival and overall survival at 48-months were 89.9% (CI: 82.4-95.5) and 92.2% (CI: 85.3-97.1), respectively. These findings underscore the potential for a consolidation strategy in CLL, wherein the addition of a mAb in patients with low tumor burden might enhance the quality of the response. The study was funded by Janssen that also supplied ibrutinib, whereas ofatumumab was supplied by Novartis.

#358 The efficacy and safety of ripertamab (SCT400) in the treatment of primary membranous nephropathy: a single center retrospective study

Abstract Background and Aims Anti-CD20 monoclonal antibody is gaining increasing clinical acceptance in the treatment of primary membranous nephropathy (PMN). Ripertamab, a novel anti-CD20 monoclonal antibody developed in China, has been shown to be non-inferior to rituximab in efficacy and safety in patients with B-cell non Hodgkin's lymphoma. We aimed to identify the efficacy and safety of ripertamab in PMN retrospectively. Method The PMN patients who were diagnosed by renal biopsy and received ripertamab-based therapy between November 1 2022 and June 30 2023 were included. The inclusion criteria were: aged ≥ 18 years, and total B-lymphocyte ratio &amp;lt; 1% after using ripertamab. The exclusion criteria were: follow-up &amp;lt; 6 months, incomplete clinical data, secondary membranous nephropathy due to malignant tumor, systemic lupus erythematosus, hepatitis, etc. The primary outcome was clinical efficacy at 6 months after initial of treatment and secondary outcomes were clinical efficacy at 3 months, safety and the occurrence of adverse events. Complete remission (CR) was defined as urine protein/creatinine ratio (UPCR) &amp;lt; 300 mg/g or 24-hour urinary protein (UP) &amp;lt; 0.3 g, serum albumin &amp;gt;35 g, and stable renal function (eGFR with ≤50% reduction compared with baseline). Partial remission (PR) was defined as UPCR or UP with ≥ 50% reduction compared with baseline, serum albumin &amp;gt;30 g, and stable renal function. No response (NR) was defined as UPCR or UP with &amp;lt; 50% reduction compared with baseline. Results A total of 31 patients were included in this retrospective study. The baseline characteristics of the study population and ripertamab treatment responses were described in Table 1. At 6 months, 20 of 31 (64.6%) patients achieved CR (n = 10, 32.3%) or PR (n = 10, 32.3%) after ripertamab treatment (Table 2). Furthermore, 21 of 31 (67.7%) patients who were not given any immunosuppressive therapy before receiving ripertamab achieved CR or PR. Non-responders showed a higher level of proteinuria and a worse renal function at baseline than those of responders. All patients achieved complete B-cell depletion. No adverse events were observed in patients in this study. Conclusion Ripertamab can effectively induce remission of PMN and have a favorable safety profile.

#657 Obinutuzumab is effective for the treatment of frequently-relapsing/steroid-dependent minimal change disease in adults

Abstract Background and Aims Higher relapse rates and steroid dependency are challenges in the treatment of minimal change disease (MCD). The aim of this study was to evaluate the efficacy and safety of obinutuzumab, a humanised type II anti-CD20 monoclonal antibody, in adults with frequently relapsing (FR) or steroid-dependent (SD) minimal change disease (MCD). Method Patients with FR/SD MCD receiving obinutuzumab at our center between September 2022 and February 2023 were enrolled. Complete remission was defined as the reduction of proteinuria to 0.3g/d. The time to remission, the relapse rate, and adverse events were evaluated. Results Six patients with FR/SD MCD were included in the present study. The median age of the patients was 30.44 years (range 18.80-72.09 years) and 3 of them were male. Prior to treatment with obinutuzumab, five patients remained in nephrotic syndrome and one patient was in partial remission after previous treatment. One or two doses of 1g obinutuzumab were given. All six patients achieved a complete remission. Five patients with nephrotic syndrome achieved complete recovery within a range of 14 to 57 days. The patient, who initially achieved partial remission, reached complete remission within 27 days after receiving the first obinutuzumab dose. The average follow-up duration was 12.53 ± 1.97 months, during which there was no observed relapse. Furthermore, None of the patients experienced infusion-related adverse effects, serious infectious complications or neutropenia following treatment with obinutuzumab. Conclusion Obinutuzumab is an effective and safe treatment option for adult patients with FR/SD minimal change disease. Further randomized trials are needed to confirm these findings.

#1649 Obinutuzumab is effective for the treatment of rituximab-resistant membranous nephropathy

Abstract Background and Aims Membranous nephropathy (MN) is a leading cause of nephrotic syndrome in nondiabetic adults. Rituximab has become the first-line therapy for patients with MN after the recognition of MN as an autoimmune disease. However, 40% of patients with MN do not respond to rituximab. Obinutuzumab is a humanized and glycoengineered type II anti-CD20 monoclonal antibody that has superior in vitro B-cell cytotoxicity compared with rituximab which might provide an attractive option for rituximab-resistant MN. We presented our single-center experience of treating MN with obinutuzumab. Method Fourteen patients with rituximab-resistant PLA2R-associated MN who received obinutuzumab at the First affiliated hospital of Xi'an Jiaotong university between January 2022 and June 2023 were included in this retrospective study. Resistance to rituximab was defined as the failure to achieve complete (urinary protein excretion &amp;lt;0.3 g/d along with normal serum albumin concentration and stable renal function) or partial (urinary protein excretion &amp;lt;3.5 g/d or with ≥50% reduction vs baseline, accompanied by improvement or normalization of serum albumin concentration and stable GFR) remission of NS in 3-6 months after 2 doses of rituximab administration. Clinical and laboratory parameters were evaluated at presentation, before and after obinutuzumab administration. Results Of all patients with an average age of 50.0 ± 13.6 years, 10 (71.4%) patients were men, 8 (57.1%) patients had hypertension and 4 (28.6%) patients had diabetes. The median disease duration was 1.3 (1.0, 4.8) years. At presentation, the proteinuria and albumin levels were 7.94 ± 4.23 g/d and 21.5 ± 3.6 g/L, respectively. The mean serum creatinine level was 70.5 ± 10.7 µmol/L and the patients had a median baseline anti-PLA2R level of 193.5 (104.5,299.2) RU/mL. Six patients had been previously exposed to steroids, alkylating agents, calcineurin inhibitors in different combinations in addition to rituximab. Both patients received 1 g of obinutuzumab on day 0 and day 15. At obinutuzumab administration, the proteinuria and albumin levels were 8.43 ± 3.36 g/d and 22.4 ± 4.0 g/L, respectively. The mean serum creatinine level was 85.1 ± 28.5 µmol/L and median anti-PLA2R level decreased to 32.7 (10.7,178.) RU/mL compared with that at presentation. After a median follow-up of 5.4 (4.0, 9.7) months after obinutuzumab therapy, complete remission was achieved in 4 (28.6%) and partial remission was achieved in 8 (57.1%) of patients. Of the remaining two patients who did not achieve complete or partial remission, 1 patient had a follow-up of 4 months and had a 33% decline in proteinuria accompanied by improvement in serum albumin. The other patient had an anti-PLA2R level higher than 1500 RU/mL (exceeding detection upper limit) at obinutuzumab administration and an inadequate follow-up of 3 months without proteinuria decline. Whereas, anti-PLA2R level decreased to 18.17 RU/ml accompanied by B-lymphocyte depletion (absolute CD19 count &amp;lt;5 cells/ml) at that time. Of the 12 patients who achieved complete or partial remission, the median time from treatment to remission was 4.7 ± 2.3 months. Two patients with longer follow-up maintained complete remission at 1 year. At first complete or partial remission, the proteinuria and albumin levels were 3.47 ± 1.99 g/d and 32.5 ± 3.3 g/L, respectively. The mean serum creatinine level was 74.8 ± 24.1 µmol/L and anti-PLA2R levels of 11 patients had a decline in the titer to &amp;lt;2 RU/ml (negative result for our immunology laboratory). B-lymphocyte depletion was achieved in all these patients. Conclusion Obinutuzumab may represent an attractive alternative therapy in patients with resistance to rituximab. Larger prospective studies are needed to validate these findings.

#1927 Efficacy and safety of ripertamab in paediatic glomerular disease

Abstract Background and Aims Anti-B-cell treatment has been shown to be an efficient tactic for glomerular disease. Ripertamab as a novel anti-CD20 monoclonal antibody developed by China, has been structurally optimized to specifically bind to the transmembrane antigen CD20, with an amino acid difference in the constant region sequence compared to rituximab. This study reports the efficacy and safety of ripertamab in children with different glomerular diseases. Method We retrospectively report the data of 140 children with a diagnosis of glomerular disease and a treatment with ripertamab in a single center Results A total of 140 children (age, 11.2 ± 3.7 years; 58.6% boys) were included, 69/140 (49.3%) steroid-dependent nephrotic syndrome (SDNS), 38/140 (27.1%) steroid-resistant but CNIs-dependent nephrotic syndrome, 18/140 (12.9%) Lupus nephritis, 5/140 (3.6%) atypical hemolytic uremic syndrome, 4/140 (2.9%) ANCA associated vasculitis, 3/140 (2.1%) membranous nephropathy and 3/140 (2.1%) IgA vasculitis nephritis. The Median (IQR) duration of disease before the application of ripertamab was 4.4 (2.3, 7.4) years. They totally received 200 courses of ripertamab. A total of 83, 55, 1, and 1 patient received one, two, three, and four courses, respectively. Ripertamab 375 mg/m2 (maximum 500 mg) were injected per course. B cell depletion could be observed in 129/140 (92.1%) children one month after ripertamab. An additional course was administered due to recovery of B-cells or relapse. Median (IQR) follow-up was 0.8 (0.5, 1.1) years. The median relapse-free period after the first course was 4.7 months (IQR, 3.8, 5.6 months). Most of the relapses developed simultaneously with recovery of B-cells. About 36.7% of these children stopped steroid during the follow-up. One or more immunosuppressant (IS) drugs needed before ripertamab infusion could be withdrawn or reduced in 109/140 patients (77.9%). None of the patients developed life-threatening adverse events. Conclusion This study suggests that ripertamab could be an effective and safe treatment for various pediatric glomerular diseases.

Inotuzumab Ozogamicin: First Pediatric Approval.

Inotuzumab ozogamicin (BESPONSA™) is a CD22-targeted monoclonal antibody drug conjugate (ADC) developed by Pfizer for the treatment of CD22-postive B-cell precursor acute lymphoblastic leukaemia (ALL). Inotuzumab ozogamicin comprises a humanized IgG4 anti-CD22 monoclonal antibody covalently linked to the potent DNA-binding cytotoxic agent N-acetyl-gamma-calicheamicin dimethylhydrazide (CalichDMH) via a linker. Inotuzumab ozogamicin binds to CD22-expressing tumour cells, facilitating the delivery of conjugated CalichDMH, which after intracellular activation induces double strand DNA breaks, ultimately leading to cell cycle arrest and apoptotic cell death. Inotuzumab ozogamicin is approved in the USA, Europe and several countries worldwide for the treatment of relapsed or refractory CD22-positive B-cell precursor ALL in adults. On 6 March 2024, inotuzumab ozogamicin received its first pediatric approval in the USA for this indication in patients aged ≥1 years. Inotuzumab ozogamicin has since been approved in Japan in March 2024 for the same indication in pediatric patients. This article summarizes the milestones in the development of inotuzumab ozogamicin leading to this first approval for the treatment of relapsed or refractory CD22-positive B-cell precursor ALL in pediatric patients.

Memory B cell–guided extended interval dosing of ocrelizumab in multiple sclerosis

Background: Ocrelizumab (OCR) is an anti-CD20 monoclonal antibody approved for the treatment of relapsing-remitting and primary-progressive multiple sclerosis (MS). We aimed to evaluate the effectiveness of an individualized OCR extended interval dosing (EID), after switching from standard interval dosing (SID). Methods: This was a retrospective, observational, single-centre study including MS patients regularly followed at the Neurocenter of Southern Switzerland. After a cumulative OCR dose ⩾1200 mg, stable patients were switched to EID (OCR infusions following CD19+ 27+ memory B cell repopulation). Results: A total of 128 patients were included in the study, and 113 (88.3%) were switched to EID with a median interval of 9.9 (8.8–11.8) months between infusions. No clinical relapses occurred; 2 (1.8%) patients experienced disability worsening. Three (2.7%) and 2 (1.8%) patients experienced new T2 brain and spinal lesions, respectively. There was a mild decrease in IgG and IgM concentrations during both SID and EID OCR regimens (β = −0.23, p = 0.001 and β = −0.07, p < 0.001, respectively). Conclusion: Switch to personalized dosing of OCR based on CD19+ 27+ memory B cell repopulation led to a great extension of the interval between infusions, with maintained clinical and radiological efficacy. Given the potential advantages in terms of safety and health costs, EID OCR regimens should be further investigated.

Zuberitamab, an innovative anti-CD20 monoclonal antibody, for patients with primary immune thrombocytopenia in China: a randomized, double-blind, placebo-controlled, phase 2 study

Primary immune thrombocytopenia (ITP) is an autoimmune disease, and rituximab (RTX) induces long-term effect as second-line treatments. Zuberitamab is an innovative anti-CD20 monoclonal antibody, which was first developed in China and launched in diffuse large B lymphoma. This study aimed to investigate the safety, efficacy, and anticipated therapeutic dose of zuberitamab in Chinese ITP patients. This randomised, double-blind, placebo-controlled, phase 2 study was conducted at 26 hospitals in China. Eligible patients were aged 18-70 years, had primary immune thrombocytopenia for more than 6 months, and did not respond or relapsed after previous treatment and had a pre-treatment platelet count of <30×109/L. Patients randomly received zuberitamab in a dose escalation (100/300/600mg) or placebo once-weekly for 4 weeks and followed up to 24 weeks. The primary endpoint is the proportion of patients with a platelet count ≥50×109/L at week 8. Secondary endpoints include the proportion of patients with platelet counts ≥50×109/L or ≥100×109/L at least once within week 12/24, the proportion of patients experiencing platelets increased twice more than baseline as well as ≥30×109/L at least once during the treatment. Adverse events, pharmacokinetic, B cell depletion and immunogenicity were also assessed. This study is registered with https://www.chictr.org.cn/as ChiCTR2100050513. From October 2021 to March 2023, 50 patients were screened for eligibility, of whom 32 patients were enrolled and randomly assigned to placebo (n=4), zuberitamab 100mg (n=10), 300mg (n=8) and 600mg (n=10) groups. The primary endpoint (PLT ≥50×109/L at week 8) was achieved by 40% of patients in the 100mg group, while none in the other groups. Within 12 weeks, the proportions of patients in each treatment group achieving at least one instance of platelet count ≥50×109/L or ≥100×109/L or an increase twice more than baseline as well as ≥30×109/L were (70%, 38%, 50%), (60%, 13%, 30%), and (80%, 50%, 70%) in zuberitamab 100/300/600mg groups, respectively. By week 24, the proportions of patients achieving these secondary endpoints remained relatively stable or showed a mild increase of around 10%. The anticipated therapeutic dose of zuberitamab was 100mg. The plasma concentration of zuberitamab showed an increasing trend with dose (100mg-600mg) and linear pharmacokinetic behavior. CD19+ B cells and CD20+ B lymphocytes rapidly declined to 0% within one week and consistently maintained reduced levels throughout the entire treatment phase in three groups. Adverse events occurred in all patients with most of them were mild to moderate, no severe infections occurred. A slight decrease in immunoglobulins was observed in the 600mg group, but gradually recovered at week 20. Three patients (2 in 100mg and 1 in 600mg group) were tested positive for anti-zuberitamab antibodies. We also observed that women, disease duration <12 months, and MAIPA+patients may have higher response rates. This study preliminarily confirmed that 100mg zuberitamab was safe and effective in treating ITP and was recommended to support further investigation. National Natural Science Foundation of China and Zhejiang Bioray Biopharmaceutical Co. Ltd.