KalVista Pharmaceuticals' unexpectedly messy path to approval ended Monday when the Food and Drug Administration signed off on its emergency treatment for swelling attacks associated with a rare, genetic disease.
Ekterly, formerly sebetralstat, is the first and only pill to treat swelling attacks that occur with hereditary angioedema, or HAE. The approval follows a rough road. The FDA was originally due to make an approval decision on June 17, but delayed that deadline, citing a lack of resources. Later, Endpoints reported FDA Commissioner Marty Makary sought to reject KalVista's drug.
KalVista shrugged off the report, saying in an email to Investor's Business Daily that it was "unaware of any internal deliberations at the FDA and we do not comment on rumors." But the biotech stock still took a hit. Shares hit a 2025 peak at 14.87 on June 9 and have since fallen more than 19%, as of the close on Friday.
On Monday, though, KalVista shares ramped up 25.7% to 15.06.
KalVista Rises On 'Relief'
Needham analyst Serge Belanger called the approval a "relief," given the FDA's original delay and "ensuing noise about additional delays."
Ekterly tries to solve a key problem in on-demand treatment for HAE swelling attacks. Other drugs are injected or infused. But those are painful and hard to carry, Chief Executive Benjamin Palleiko told IBD. These drawbacks often cause patients to skip or delay treatment for hours, allowing the swelling to become significantly worse.
Swelling attacks can take place anywhere, but often occur in the extremities, stomach or larynx. The label for Ekterly is clean with no restrictions for treating attacks in any location, Belanger said in a report to clients. He sees a peak of $700 million in sales.
"We believe there are key dynamics specific to the HAE on-demand market, such as a stable patient pool, low competition, broad payer access (with mostly commercial coverage), and high interest for oral treatments that should provide confidence for a strong sebetralstat launch starting in mid-2025," he said.
Leerink Partners analyst Joseph Schwartz called the pill the "holy grail in HAE."
"Convenience and route of administration are major shortcomings of the legacy treatment options, and we see a significant opportunity for oral Ekterly," he said in a report.
Stringer forecasts gross peak sales of $470 million in the U.S. and Europe.
This story has been updated to correct Joseph Schwartz's name.
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