BLISS-LN trial revisited: function matters.

This post hoc analysis of the Belimumab International Study in Lupus Nephritis (BLISS-LN) shows belimumab effectively reduced the time to 30% and 40% decreases in estimated glomerular filtration rate and persistent decreases in estimated glomerular filtration rate. Subgroup analysis found belimumab was most effective in proliferative lupus nephritis, and that there was no apparent benefit from the addition of belimumab in those with baseline nephrotic range proteinuria nor in those receiving cyclophosphamide/azathioprine. These results raise questions about trial end points and their relationship to long-term kidney function, the outcome of most importance to patients, caregivers, and health professionals alike.