ImmunityBio Plunges 23% After FDA Warning Over Anktiva Claims
Regulator says promotional materials overstated cancer therapy's effectiveness in third compliance action
ImmunityBio shares plunged 23% on Tuesday after the US Food and Drug Administration issued a warning letter accusing the company of making false and misleading promotional claims about its flagship bladder cancer treatment, Anktiva.
The stock dropped $2.18 to $7.22, wiping more than $2.6bn from the company's $8.7bn market capitalization, according to market data. The steep decline came after the FDA's Office of Prescription Drug Promotion found that a television advertisement and a podcast featuring top executives overstated the therapy's effectiveness beyond its approved uses.
The promotional materials, which featured chief executive Richard Adcock and executive chairman Dr. Patrick Soon-Shiong, suggested that Anktiva could "treat all cancers," prevent cancer in individuals exposed to radiation, and serve as a single injection treatment, according to an analysis by Investing.com. However, the drug is specifically approved only for adult patients with BCG-unresponsive non-muscle invasive bladder cancer with carcinoma in situ, and must be administered directly into the bladder in combination with BCG therapy.
"These representations were not supported by clinical data," the FDA stated in the warning letter, noting that the company failed to properly present risk information and omitted material facts about the drug's approved indication.
The regulatory action marks the third time the FDA has communicated with ImmunityBio regarding similar promotional issues. The agency had previously sent "untitled letters" to the company's subsidiary, Altor BioScience, in September 2025 and January 2026 concerning misleading claims on its websites about Anktiva.
ImmunityBio has been given 15 working days to respond to the warning letter with a plan to address the violations and implement corrective communications for audiences who received the misleading promotional materials, according to the FDA's notice.
The enforcement action poses significant risks to the company's commercial strategy for Anktiva, its first FDA-approved therapy and primary revenue driver. The company reported $113.3m in trailing twelve-month revenue but remains unprofitable with a loss of $0.38 per share and negative book value of $0.50 per share, according to company filings.
Despite the regulatory setback, analysts maintain bullish expectations for the stock. The consensus price target sits at $14.80, more than double Tuesday's closing price, with four analysts rating it a buy—including one strong buy—according to market data. However, the governance concerns raised by the repeated FDA violations could test that confidence.
The warning letter highlights broader challenges in biotechnology commercialization, where companies face intense pressure to drive adoption of innovative therapies while navigating strict promotional regulations. Anktiva represents a novel immunotherapy approach for patients with limited treatment options, making accurate communication about its capabilities critical for physician and patient trust.
ImmunityBio's insider ownership stands at 63.7%, one of the highest levels in the biotechnology sector, while institutional ownership remains relatively low at 16.9%. The stock had previously rallied to a 52-week high of $12.43 before Tuesday's steep decline, reflecting investor enthusiasm for the company's cancer immunotherapy platform.
The company did not immediately respond to requests for comment on the FDA warning or its plans for corrective action.