Ligand Pharmaceuticals Incorporated (NASDAQ:LGND) partner Retrophin, Inc. today announced additional results from the Phase 2 DUET study of sparsentan for the treatment of focal segmental glomerulosclerosis (FSGS), a rare kidney disorder without an FDA-approved pharmacologic treatment that often leads to end-stage renal disease. These new findings are being presented today in the late-breaking High-Impact Clinical Trials oral session at the American Society of Nephrology (ASN) Kidney Week 2016 in Chicago. "The prevalence of FSGS is on the rise and without an approved therapy, many patients diagnosed with the disorder face a progressive decline and the high likelihood of end-stage renal disease," said Howard Trachtman, MD, Professor of Pediatrics; Director, Division of Pediatric Nephrology, NYU School of Medicine, NYU Langone Medical Center. "These findings from the DUET study underscore the potential of sparsentan as a first-in-class treatment for FSGS." As announced in September, top-line data from DUET showed the sparsentan treatment group achieved statistical significance in the study's primary efficacy endpoint, reduction of proteinuria. These results showed a greater than two-fold reduction of proteinuria compared to irbesartan, after an eight-week, double-blind treatment period. An analysis of the secondary endpoint presented today showed that a significantly greater proportion of patients receiving sparsentan achieved modified partial remission of proteinuria, compared to irbesartan-treated patients. Modified partial remission, defined as proteinuria levels of less than or equal to 1.5 g/g and greater than 40 percent reduction of proteinuria from baseline, is associated with long-term preservation of renal function in FSGS. In addition, four patients receiving sparsentan achieved complete remission, compared to zero irbesartan-treated patients. Also presented today was a post-hoc, intention-to-treat (ITT) analysis showing that the sparsentan treatment group again demonstrated a greater than two-fold reduction of proteinuria, compared to irbesartan. Further analysis of the safety database from the initial eight-week, double-blind treatment period presented today showed sparsentan was generally safe and well-tolerated.