Travere Therapeutics offered a disappointing update from a two-year study of a kidney disease drug, and TVTX stock crashed Tuesday.
The company tested its drug, sparsentan, in patients with focal segmental glomerulosclerosis, or FSGS. The condition causes scarring on the kidneys. After 108 weeks, sparsentan patients showed improvement on a measure of how well the kidneys are working. But the result wasn't statistically significant.
Analysts cautioned against reading too much into the results for another Travere program in a kidney disease called immunoglobulin A nephropathy, or IgAN. Sparsentan sells under the brand name Filspari as a treatment for IgAN. But Filspari's accelerated approval is contingent upon a confirmatory study.
SVB Securities analyst Joseph Schwartz says both FSGS are IgAN are glomerular diseases, which involve damage to nerve clusters called glomeruli. This lets protein and sometimes red blood cells leak into the urine, and impacts the kidneys' ability to clear waste. But they are distinctive diseases, he said.
"As the trial miss increases regulatory uncertainty, we are lowering our probability-of-success in FSGS to 50% from 75% and trimming our sales estimates there," he said in a report to clients. "But we're not wavering on our stance that this has zero read-through to IgAN."
Still, on today's stock market, TVTX stock plummeted 30.8%, ending the regular session at 15.65. Shares were consolidating with a buy point at 30.45, but dropped well below the lower bound of that base on the news, according to MarketSmith.com.
TVTX Stock: A Potential Yearlong Delay
Wedbush analyst Laura Chico noted that improvement in estimated glomerular filtration rate, or eGFR, is tricky in patients with the kidney disease FSGS. This metric examines how well the kidneys are working. Sparsentan outperformed a standard drug in the study, but the results weren't statistically significant.
Sparsentan patients showed a 50% improvement in the level of protein in their blood, compared with a 32% reduction for patients who received the standard drug. That appears durable after roughly two years, Chico said. But the results were stronger in IgAN patients.
Chico kept her outperform rating on TVTX stock but lowered her price target to 27 from 29.
"What now?" she said in a report. "Travere will complete more fulsome analyses of the study data and meet with the Food and Drug Administration to better understand potential paths forward for sparsentan in FSGS."
Chico expects the drug to be delayed by one year.
Follow Allison Gatlin on Twitter at @IBD_AGatlin.
