There is no drug approved to treat FSGS, a leading cause of kidney failure
The core idea stands, but key numbers or details have changed.
TaughtFocal segmental glomerulosclerosis scars the kidney's filters and marches toward dialysis or a transplant. There is no drug approved specifically for it; doctors borrow steroids and blood-pressure medicines off-label and hope.
NowOn 13 April 2026 the FDA gave full approval to sparsentan (Filspari) as the first medicine ever approved specifically to treat FSGS, based on the phase 3 DUPLEX trial showing it reduced the protein leakage that drives the disease.
What actually happened
FSGS is not a single disease so much as a pattern of scarring with many causes, which is part of why it went so long without a dedicated treatment. Sparsentan is a dual blocker of two receptors, endothelin and angiotensin, that both push the kidney toward damage, and it had already been approved for a different kidney disease, IgA nephropathy, before FSGS.
The fair framing is 'updated,' not 'cured.' Sparsentan lowers proteinuria, a marker strongly tied to how fast kidneys fail, rather than proven to stop every patient's decline, and FSGS remains serious. But the specific line taught for decades (that there is no approved drug for this disease, only improvised off-label combinations) is no longer true. There is now one, by name.
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Who was taught this
Still standard through 2026, so anyone who finished school between 1950 and 2026 learned the earlier version.