Nearly half of patients with newly diagnosed lupus nephritis (LN) in a US cohort began treatment with an immunosuppressant, real-world data show, but there is substantial variation in regimen selection, treatment duration, and therapy switching. Anisha Patel, PhD, of Genentech, Inc., presented the data at the American College of Rheumatology Convergence 2025, held October 24 to 29 in Chicago, Illinois.

These study findings highlight evolving LN management in US clinical practice and underscore the need for clinician awareness of new therapies and updated guidelines.

Using 2018-2023 US health insurance claims from the IQVIA PharMetrics Plus database, investigators conducted a retrospective cohort analysis of 2052 adults with newly diagnosed LN to characterize contemporary treatment practices. The cohort was 82% female with a mean age of 44 years, and 45% lived in the South. Most (94%) had private insurance, and 74% had a prior diagnosis of systemic lupus erythematosus. Before LN diagnosis, 35% had used an immunosuppressant, mostly systemic corticosteroids (60%) and nonsteroidal options (35%). The study's mean follow-up was 2.5 years.

Nearly all patients (95%) received at least 1 LN-related treatment, with a median start time of 11 days from diagnosis. Immunosuppressant therapy was used as the first line of treatment in 946 patients (48%), with mycophenolate mofetil most common (66%), followed by azathioprine (10%), and/or belimumab (6%). Median treatment duration varied across these agents, with 257 days for mycophenolate mofetil, 254 for azathioprine, and 322 for belimumab.

Among those taking a first-line immunosuppressant, 80% also received systemic glucocorticoids, 65% were prescribed antimalarials, and 54% took antihypertensives. At the end of follow-up, 27% remained on their initial regimen for a median of 456 days, while 19% transitioned to a second line of therapy, typically mycophenolate mofetil, belimumab, or azathioprine. A total of 16% discontinued and later restarted therapy after more than 90 days, and 37% permanently discontinued immunosuppressants.

In addition, 18% of patients who initially received non-immunosuppressive therapy later began an immunosuppressant regimen. This dynamic treatment activity illustrates the clinical complexity of LN management and individualized decision-making across treatment phases.

"Variability in treatment duration and regimens reflects dynamic patient needs and treatment practices," Dr Patel's team stated. "Understanding these patterns is essential for optimizing LN care and informing future monitoring of treatment changes following practice guideline updates and availability of newer therapies."

References:

Patel A, Miller A, Lindsay L, et al. Real-world immunosuppressant treatment patterns in lupus nephritis: a retrospective claims database analysis in the United States. Presented at: American College of Rheumatology Convergence 2025; October 24-29, 2025; Chicago, IL. Abstract 1038.