ImmunityBio shares fall on FDA warning letter over cancer therapy claims in ad

March 24 (Reuters) - Shares of ImmunityBio IBRX.O fell 20% on Tuesday after the U.S. Food and Drug Administration issued a warning letter that said a television advertisement and podcast promoting its cancer therapy were false or misleading and violated federal law.

ImmunityBio's Anktiva was approved for a type of bladder cancer in April 2024.

"These violations are concerning from a public health perspective because the promotional communications create a misleading impression that Anktiva, a treatment for a certain type of bladder cancer, can cure and even prevent all cancer," the FDA said in the letter issued to the company on March 13.

The agency said the direct-to-consumer materials, which featured CEO Richard Adcock and Executive Chairman Patrick Soon‑Shiong, created the impression that Anktiva could cure cancer, prevent its return, work as a single-agent therapy, or function as a cancer vaccine.

ImmunityBio did not immediately respond to a Reuters request for comment.