Study: Rituximab Effective and Well Tolerated in Treating Nephrotic Syndrome

Idiopathic nephrotic syndrome, which is characterized by edema, hypoalbuminemia, proteinuria, and hyperlipemia, is the most prevalent chronic glomerular disease in childhood. Although the disease can often be treated successfully with steroids, approximately 10% to 20% of patients develop resistance to steroid therapy. These patients may be treated with cyclosporine, but this therapy is associated with toxicity, and patients may also have disease resistant to cyclosporine. Therefore, identifying alternative treatments is critical for this group of patients.

Some case reports have suggested that rituximab can effectively treat nephrotic syndrome, and a recent study sought to assess the safety and effectiveness of rituximab in treating patients who have steroid- and cyclosporine-resistant pediatric nephrotic syndrome. The study included patients at Tehran, Iran’s Ali Asghar Children’s Hospital who were younger than 18 years and had steroid- and cyclosporine-resistant or steroid- and cyclosporine-dependent nephrotic syndrome between 2014 and 2015.

The primary endpoint of the study was treatment response. A complete response was defined as no proteinuria, and a partial response was defined as a reduction of more than 50% in protein in the patient’s 24-hour urine sample from the beginning of treatment until 3 months after the last dose.

In total, 40 patients received rituximab at a dose of 375 mg per m² once per week for 4 weeks and were followed for up to 2 years; 23 had steroid- and cyclosporine-resistant disease, 7 had late drug-resistant nephrotic syndrome, and 10 had steroid- and cyclosporine-dependent disease.

The researchers found the following with respect to response to treatment with rituximab:

• 24 patients (60.0%) had a complete response
• 3 patients (7.5%) had a partial response
• 13 patients (32.5%) had no significant response
• Among patients with steroid- and cyclosporine-resistant disease, 8 (34.8%) had a complete response and 3 (13%) had a partial response. Recurrence of disease occurred in 6 patients who responded to treatment during 6 months of follow-up.
• In patients with late drug-resistant disease, 6 (85.7%) had a complete response and none had a partial response. Recurrence of disease occurred in 2 patients during the follow-up period.
• In patients with steroid- and cyclosporine-dependent disease, all 10 patients had a complete response. In this group, no disease recurrences were observed in the follow-up period.

Adverse events were noted in 4 patients: 2 had leukopenia, 1 had alopecia, and 1 had eosinophila.

The researchers concluded that rituximab was effective in treating nephrotic syndrome, and was well tolerated. “In fact,” wrote the authors, “this medication can be administered with full confidence because of its high clinical efficacy, minimized drug-related side effects, and also reduced recurrence, especially in those children with steroid- and cyclosporine- dependent nephrotic syndrome.”

Reference

Hoseni R, Sabzian K, Otukesh H, et al. Efficacy and safety of rituximab in children with steroid- and cyclosporine-resistant and steroid- and cyclosporine-dependent nephrotic syndrome. Iran J Kidney Dis. 2018;12(1):27-32. http://www.ijkd.org/index.php/ijkd/article/view/3317/982. Published January 2018. Accessed February 12, 2018.