Disease-Modifying Therapies in Lupus Nephritis: A Narrative Review Evaluating Currently Used Pharmacologic Agents

As more lupus nephritis (LN) medications become available, identifying treatments that are disease-modifying is critical in making treatment decisions. Based on our 2022 published working definition of LN disease modification as 'minimizing disease activity with the fewest treatment-associated toxicities and slowing progression to end-stage kidney disease' (ESKD), the objective of this review was to classify current LN treatments according to the proposed kidney disease modification criteria, excluding toxicities. Based upon a selection of LN clinical trial (n = 27) and observational study (n = 20) publications, as well as the authors' clinical experiences, we evaluated the disease modification potential for 16 LN treatments (inclusive of antimalarials, glucocorticoids, immunosuppressants, calcineurin inhibitors and biologics) according to the proposed kidney disease activity and organ damage criteria at year 1, years 2-5, and > 5-year time points. Fulfilling criteria at year 1 and years 2-5 was considered evidence for disease modification potential. Satisfying criteria at > 5 years (slowing or preventing progression in SLICC/ACR Damage Index [SDI] and ESKD, and/or doubling of serum creatinine) was used to confirm disease modification. Each treatment was designated as one of the following at each time point: (a) criterion met; (b) inconclusive; (c) no available supportive data. This review excluded an assessment of potential toxicities. All LN treatments met at least one of the potential kidney disease-modification criteria at any time point, but limited relevant data in the literature meant disease modification > 5 years could only be confirmed for cyclophosphamide. Belimumab met more criteria across the three time points than any other biologic treatment but lacked > 5-year data to confirm disease modification. Further research is needed to support the classification of LN treatments as disease modifiers, particularly for > 5 years. We discuss considerations for future studies, challenges to the classification, and possible updates to published criteria.