What happened

The stock of Travere Therapeutics (TVTX 4.10%) was on the decline by almost 17% in midafternoon trading Wednesday. That was on the back of dispiriting regulatory news from the rare-disease biotech.

So what

Travere disclosed that the Food and Drug Administration won't grant accelerated approval to its pipeline drug sparsentan as the company had hoped. According to Travere, the regulator said it cannot support such approval based on the company's interim analysis from a recent phase 3 trial of the drug.

A researcher studying a sample in a petri dish.

Image source: Getty Images.

That's a big setback, as sparsentan -- which treats a kidney disorder called focal segmental glomerulosclerosis (FSGS) -- is a leading pipeline drug for Travere. It wanted to formally submit it for accelerated approval in the second half of this year; it no longer expects to do so.

Still, it continues to believe in sparsentan, and is hopeful for its potential. "Based upon our ongoing dialogue with FDA, we believe the [kidney function] data need to further mature to support our New Drug Application for accelerated approval in this indication," the company quoted CEO Eric Dube as saying.

He added that he and his team "still have a potential opportunity to pursue a path to an accelerated approval submission in the U.S. next year."

Now what

The immediate prospects for sparsentan might be brighter in the European Union, where Travere says it has "received administrative support" for getting conditional marketing authorization for the drug. As with its previous U.S. ambitions, the biotech wants to put sparsentan on the market in the second half of 2021.