TOPLINE

Maintenance therapy and treatment duration longer than 6 months are associated with improved relapse-free survival in patients with monoclonal gammopathy of renal significance (MGRS), according to a retrospective analysis of 50 patients. Among patients with a plasma cell clone, median relapse-free survival was not reached with maintenance therapy vs 2.9 years without maintenance.

METHODOLOGY

• The role of maintenance strategies in MGRS remains undefined, and the benefit of autologous stem cell transplantation in the era of novel therapies has not been well studied.
• Researchers retrospectively analyzed 50 patients with biopsy-provenMGRS treated across three institutions in the US between 2010 and 2025, with median follow-up of 6.15 years.
• A total of 42 patients had a plasma cell clone and eight patients had a B-cell clone; the most common histopathology was proliferative glomerulonephritis with monoclonal immunoglobulin deposits (72%).
• Among patients with a plasma cell clone, 37 received treatment with common induction regimens including daratumumab-based therapy (32.4%), cyclophosphamide-bortezomib-dexamethasone (29.7%), and bortezomib-dexamethasone (29.7%).
• Maintenance therapy was administered to 13 of 37 treated patients (35.1%) in the plasma cell group, using the same backbone as induction but given less frequently.
• Relapse-free survival was defined as a composite endpoint including increase in monoclonal protein, estimated glomerular filtration rate decline > 25%, increased proteinuria, need for repeat kidney biopsy, or death.

TAKEAWAY

• Among patients with a plasma cell clone achieving complete response or very good partial response, median relapse-free survival was 8.4 years vs 1.19 years for those with partial response or lower (P = .017).
• Maintenance therapy was independently associated with reduced risk for relapse in multivariate analysis (hazard ratio [HR], 0.13; P = .043).
• Induction duration > 6 months was independently associated with improved overall survival (HR, 0.21; P = .03).
• Autologous stem cell transplantation showed no significant differences in relapse-free survival or overall survival compared with patients who did not undergo transplantation.

IN PRACTICE

“Maintenance therapy and prolonged treatment duration may improve disease control in MGRS and support further evaluation of extended treatment strategies to prevent renal damage and improve long-term outcomes,” the authors of the study wrote.

SOURCE

The study was led by Francesca Cottini, MD, Ohio State University Wexner Medical Center in Columbus, and Matias Sanchez, MD, University of Illinois Chicago in Chicago. It was published online in Blood Advances.

LIMITATIONS

The retrospective design introduces potential selection bias, and the relatively small sample size of 50 patients limits statistical power. The predominance of proliferative glomerulonephritis with monoclonal immunoglobulin deposits (72%) may affect generalizability to other MGRS subtypes. Limited data on B-cell clones (only 8 patients) and post-kidney transplant maintenance restricted the ability to draw firm conclusions on these subgroups. The absence of validated criteria for disease progression in MGRS required use of a composite endpoint that, while clinically meaningful, has not been formally validated.

DISCLOSURES

Cottini disclosed receiving consulting or advisory role fees from Sanofi and research funding from Pfizer. Sanchez disclosed receiving consulting or advisory role fees from Janssen and Regeneron. The remaining authors reported having no competing financial interests.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.