By Reuters Staff
NEW YORK (Reuters Health) - Following steroid withdrawal, the anti-CD20 monoclonal antibody rituximab is effective in maintaining long-term remission of steroid-dependent nephrotic syndrome (SDNS) while low-dose mycophenolate mofetil (MMF) is not, according to results of a randomized controlled trial.
"Given the limited adverse effects, rituximab should be considered as the main steroid-sparing drug in patients with SDNS," researchers write in JAMA Pediatrics.
Data are conflicting on the ability of MMF to maintain steroid-free remission in children with SDNS, Dr. Gian Marco Ghiggeri of Instituto Giannina Gaslini, in Genoa, Italy, and colleagues note. The minimum dose of MMF sufficient to maintain remission of SDNS is unknown, and variable doses ranging from 700 to 1,200 mg/m2 daily have been reported.
They designed a randomized clinical trial to test the superiority of a single dose of rituximab (375 mg/m2) versus a low-dose of MMF (350 mg/m2 twice daily) in preventing the recurrence of SDNS.
Participants were between three and 24 years old with SDNS requiring prednisone 0.3 to 1.0 mg/kg/d during at least six months before enrollment.
After 30 participants were enrolled (15 in each group), the study was stopped due to "unexpectedly" high rates of relapse in the MMF group, the team reports.
In the MMF group, there were 12 relapses and only three remissions. In the rituximab group, there were only two relapses (none in the first six months) and 13 remissions. The odds of relapse were significantly higher with MMF (odds ratio, 26; 95% confidence interval, 2.9 to 311.0).
The median time to the relapse in the MMF group was 3.15 months (95% CI, 2.5 to 9.9 months). No adverse effects were observed in either group and none related to rituximab infusion.
"This study aimed to address the efficacy of low-dose MMF, and the inefficacy provides useful evidence for designing future trials," the research team writes.
The study showed that rituximab is effective in maintaining long-term remission of SDNS, while MMF given at low dose (350 mg/m2 twice daily) is not.
"The effect of higher doses (1200 mg/m2)" deserves "testing in randomized clinical trials. Lack of efficacy of low-dose MMF may have implications in clinical practice or research of other immune-mediated conditions," they say.
Dr. Ghiggheri did not respond to a request for comment by press time.
The study had no commercial funding and the authors have indicated no relevant disclosures.
SOURCE: https://bit.ly/3dCM6kH JAMA Pediatrics, online February 22, 2021.