CSL’s sparsentan did not achieve primary endpoint in glomerulosclerosis

CSL announced topline primary efficacy results from the pivotal Phase 3 DUPLEX Study of sparsentan, a Dual Endothelin Angiotensin Receptor Antagonist – DEARA -, in focal segmental glomerulosclerosis – FSGS – from its partner Travere Therapeutics. At the end of the 108-week double-blind period, sparsentan was observed to have a 0.3 mL/min/1.73m2 per year favorable difference on eGFR total slope and a 0.9 mL/min/1.73m2 per year favorable difference on eGFR chronic slope compared to the active control irbesartan, which was not statistically significant. After 108 weeks of treatment, sparsentan achieved a mean reduction in proteinuria from baseline of 50%, compared to 32% for irbesartan. Results from the two-year analysis demonstrated that sparsentan was well-tolerated and has shown a comparable safety profile to irbesartan. The secondary, topline exploratory and hard endpoints in the study trended favorably for sparsentan. A preliminary review of the safety results through 108 weeks of treatment indicate sparsentan has been generally well-tolerated and the overall safety profile in the study to date has been generally consistent between treatment groups. Travere Therapeutics intends to complete a full evaluation of the data from the DUPLEX Study and work with study investigators on future presentations and publication of the results at an upcoming medical meeting and/or in a peer-reviewed publication.