Travere Therapeutics (NASDAQ:TVTX) shares surged 44% on Tuesday after the U.S. Food and Drug Administration approved FILSPARI for the treatment of focal segmental glomerulosclerosis (FSGS), a rare kidney disorder.
The FDA cleared FILSPARI to reduce proteinuria in both adult and pediatric patients aged 8 and older with FSGS who do not have nephrotic syndrome. The approval makes FILSPARI the first and only FDA-approved therapy for FSGS, expanding its use beyond its existing indication in IgA nephropathy.
The company estimates that more than 30,000 patients in the U.S. fall within the eligible population for treatment—those with FSGS without nephrotic syndrome. Nephrotic syndrome is typically defined by proteinuria exceeding 3.5 g per 24 hours, along with edema and albumin levels below 3.0 g/dL.
In the Phase 3 DUPLEX study, patients receiving FILSPARI achieved a 46% reduction in proteinuria from baseline to Week 108, compared with a 30% reduction in patients treated with the maximum labeled dose of irbesartan. Among patients without nephrotic syndrome, FILSPARI delivered a 48% reduction versus 27% for irbesartan over the same period.
Patients treated with FILSPARI also showed improvements in kidney function, with an increase in eGFR of 1.1 mL/min/1.73 m² compared to baseline at Week 108. The drug was generally well tolerated in both adult and pediatric populations, with a safety profile similar to that of irbesartan.
Guggenheim analyst Vamil Divan raised his price target on the stock to $54 from $49 while maintaining a Buy rating. He noted: “Overall, we believe the final label is better than we expected, with the approved population broader than our prior working assumption in that it spans both primary and secondary FSGS rather than being limited to the primary/genetic population that we believe was the management’s and Street’s base case expectation.”