(Reuters Health)—Intravenous belimumab combined with standard lupus therapy can help preserve kidney function in patients with active lupus nephritis and cut the odds of death or a renal-related event by half, a phase 3 multinational study has concluded.1
After two years of therapy, 43% of 224 volunteers getting the drug monthly showed a renal response compared to 32% of the same number of patients receiving placebo (P=0.03).
Thirty percent had a complete renal response vs. 20% with placebo (P=0.02). The difference was seen from the twelfth week onward.
A complete response was a ratio of urinary protein to creatinine of less than 0.5, an estimated glomerular filtration rate that was no worse than 10% below the value before a renal flare or at least 90 mL per minute per 1.73 square meters, and no use of rescue therapy. For a partial response, the urinary protein/creatinine had to be 0.7 or lower, the estimated glomerular filtration rate had to be no worse than 20% below the pre-flare value or at least 60 mL per minute or higher, and no rescue therapy.
Death or a renal-related event was seen in 35 of belimumab patients compared with 63 among placebo recipients (P=0.001).
The study was financed by GlaxoSmithKline, which helped collect, analyze and interpret the data.
“Most of the treatment effect was seen in patients who had received mycophenolate mofetil. No benefit was present in the subgroup of patients who received cyclophosphamide-azathioprine,” says Dr. Michael Ward and Dr. Maria Tektonidou in an editorial in The New England Journal of Medicine, where the study appears.2
Induction treatment was not randomly assigned. “If patients with more severe nephritis were preferentially treated with cyclophosphamide, a likely inclination among most physicians, the trial may be telling us that belimumab enhances responses only among less severely affected patients,” writes Dr. Ward of the U.S. National Institutes of Health and Dr. Tektonidou of the National and Kopodistrian University in Athens.
They also note that the primary endpoint of the study, known as BLISS-LN, was changed in 2017, which was five years after the trial began.
Lupus nephritis becomes a problem in 25% to 60% of patients with systemic lupus erythematosus. In spite of treatment, 27% to 66% have flares of nephritis and 10% to 30% develop end-stage kidney disease.
The rate of serious adverse events was 26% with the drug and 30% with placebo. Treatment-related serious advents were seen in 10% and 11% respectively.