XENE Stock Rallies 50% On Epilepsy Trial Data, But One Analyst Thinks Rival Biohaven Still Has ‘Room To Differentiate’

Xenon said that the late-stage study met its primary endpoint of median percent change from baseline in monthly FOS frequency to week 12 in both the 25 mg and 15 mg dose groups compared to placebo.

• Xenon plans to submit a new drug application for azetukalner to the U.S. Food and Drug Administration for the treatment of focal onset seizures in the third quarter of 2026.
• CEO Ian Mortimer said that the trial results “exceeded expectations.”
• Raymond James, meanwhile, kept a ‘Strong Buy’ rating on Biohaven shares following competitor Xenon’s data readout.

Xenon Pharmaceuticals Inc. (XENE) on Monday announced that it has commenced an underwritten public offering of $500 million of its common shares on the heels of the company announcing positive results from a trial of azetukalner in focal onset seizures (FOS).

The company said that the late-stage study met its primary endpoint of median percent change from baseline in monthly FOS frequency to week 12 in both the 25 mg and 15 mg dose groups compared to a placebo.

Shares of XENE closed 50% higher in the regular hours of trading.

Trial Data

With the higher 25 mg dose, a 53.2% median percent change from baseline in monthly FOS frequency was observed, compared with 10.4% for the placebo, the company said.

Azetukalner also demonstrated a safety and tolerability profile consistent with prior studies, prompting the company to plan submitting a new drug application to the U.S. Food and Drug Administration (FDA) for the treatment of focal onset seizures in the third quarter of 2026.

CEO Ian Mortimer said that the trial results “exceeded expectations.”

“Epilepsy is one of the most common neurological diseases, and foundational antiseizure medications do not provide sufficient seizure control for up to 50% of patients, so we are very optimistic about the opportunity for azetukalner to meaningfully shift the epilepsy treatment paradigm,” said CMO Chris Kenney.

Focal onset seizures, or epilepsy, originate in one localized area of the brain, causing symptoms based on that specific region.

Wall Street Reaction

Following the trial data announcement, several analysts hiked their price targets on the stock, while also reflecting on the news’ impact on the shares of Biohaven (BHVN), which is developing an investigational drug Opakalim for epilepsy, depression, and pain.

Jefferies raised the firm's price target on Xenon Pharmaceuticals to $100 from $65 and kept a ‘Buy’ rating on the shares. The firm said it thinks azetukalner has the attributes of a top-selling epilepsy pill, driven by best-in-class focal epilepsy data. In 2026, Xenon shares could grind higher as Big Pharma interest rises and as the Street gauges azetuklaner's peak sales potential, the analyst told investors in a research note.

Biohaven Still Holds Chance

Raymond James, meanwhile, kept a ‘Strong Buy’ rating on Biohaven shares following competitor Xenon’s data readout. Azetukalner showed efficacy in-line with expectations, but with a meaningful safety disadvantage, giving opakalim room to differentiate, it said. The firm believes the results continue to highlight an opportunity for opakalim, or BHV-7000, which has shown meaningful evidence of efficacy with better safety and tolerability.

Raymond James expects Biohaven to present topline results from the first pivotal trial for opakalim, testing a 25 mg and 50 mg dose, in the second half of 2026, which will more concretely establish the target product profile.

How Did Stocktwits Users React?

On Stocktwits, retail sentiment around XENE stock rose from ‘bullish’ to ‘extremely bullish’ over the past 24 hours, while message volume increased from ‘high’ to ‘extremely high’ levels.

XENE stock has gained 83% over the past 12 months.

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