Corticosteroids Plus Rituximab Not Likely to Injure Kidneys of SSc Patients

High doses of corticosteroids may be given alongside rituximab, used at lower doses, without affecting the kidneys of people with scleroderma, a study reports.

The retrospective study, “Effect of short interval rituximab and high‐dose corticosteroids on kidney function in systemic sclerosis: long‐term experience of a single center,” was published in The International Journal of Clinical Practice.

Scleroderma, also known as systemic sclerosis (SSc), causes progressive scarring in the skin and internal organs, including the kidneys.

Scleroderma renal crisis (SRC) is a rare but established complication of SSc, and can progress to end-stage kidney disease. A major risk factor for its development is the use of corticosteroids, a class of medications normally used to control inflammation.

In patients who experience adverse reactions to rituximab — an immunosuppressive antibody-based therapy developed by Roche that has been found to be safe and effective at easing some SSc symptoms — the use of corticosteroids is unavoidable.

Investigators at the Medical University of Graz, in Austria, evaluated the long-term safety and effectiveness of high-dose corticosteroid use in people with SSc.

They reviewed the medical records of 35 people (27 women and eight men, median age of 52), treated at the university’s Department of Internal Medicine between 2010 and 2019.

Treatment consisted on a low-dose regimen of rituximab (500 mg at study’s start and day 14, and then twice every three months) along with a high-dose, 100 mg course of intravenous prednisone given 30 minutes before each rituximab administration.

Kidney health was evaluated with each rituximab treatment, using the estimated glomerular filtration rate (eGFR).

When rituximab was started, one patient already had poor kidney function, as evident in an eGFR of less than 60 milliliters per minute per 1.73 square meters (mL/min/1.73m²). But in general, kidney function was within a normal range — median eGFR of 96 mL/min/1.73m² — in the patients when they began the study.

Rituximab treatment was preceded by high doses of prednisone for a median of 3.4 years.

During follow-up, eGFR was estimated to have dropped by 1.98 mL/min/1.73m² each year. At the end of the study’s observation period, eGFR had fallen to a median of 88.4 mL/min/1.73m².

Still, none of the patients in this analysis developed SRC or experienced a significant loss of kidney function during those years.