Abivax Drops 32% On Cancer Signal: Jefferies Warns Of ‘Real’ Overhang But Retail Calls Selloff An ‘Overreaction’

• Jefferies downgraded Abivax to ‘Hold’ from ‘Buy’ and slashed the price target to $90 from $160, a 30% potential downside from the stock’s closing price on Monday.
• Abivax said its late-stage trial to treat ulcerative colitis showed strong results.
• However, there was a small number of reported skin cancer cases and other malignancies in the higher-dose group.

Shares of Abivax SA (ABVX) tumbled 32% in premarket trading on Tuesday after a cancer-related signal cast a shadow over its late-stage ulcerative colitis program, prompting Jefferies to turn cautious and warn that the unexpected outcome “complicates matters.”

ABVX shares are on track to crack their 200-day moving average for the first time since July 2025.

ABVX’s Promising Data Clouded By Cancer Update

On Monday, Abivax said its late-stage trial to treat ulcerative colitis showed strong results, with both the 25 mg and 50 mg doses of Obefazimod helping about 51% of patients achieve clinical remission at Week 44, compared with 10.4% on placebo.

However, there was a small number of reported skin cancer cases and other malignancies in the higher-dose group. Abivax said the events were rare, occurred mainly in older patients, and were unrelated to treatment.

Jefferies Says Overhang Will Be Real

Jefferies responded by downgrading Abivax to ‘Hold’ from ‘Buy’ and slashing the price target to $90 from $160, a 30% potential downside from the stock’s closing price on Monday.

Analyst Faisal Khurshid noted that while the study delivered the best-in-class efficacy, the cancer signal “complicates matters,” according to The Fly.

Khurshid noted that the “overhang will be real” and investor concerns could persist since no major data catalysts are expected over the next year.

However, Citizens raised the price target to $187 from $131 and maintained an ‘Outperform’ rating, stating Obefazimod achieved clinical remission rates far above expectations.

Retail Says ABVX Dip Is Overblown

Despite the pre-market slump, retail sentiment on Stocktwits shifted from ‘neutral’ to ‘extremely bullish’. It was among the most buzzing stocks on the platform, with message volumes increasing by a whopping 14,500% over a 24-hour period.

One user said the stock’s drop seems like an “overreaction.”

Another user said the safety issue was “overblown” and urged adding on the dips.

The stock has declined nearly 12% so far in 2026.

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