FDA issues warning letter to ImmunityBio over misleading promotion of NAI

The FDA has issued a warning letter to ImmunityBio citing false or misleading promotional communications related to nogapendekin alfa inbakicept-pmln (NAI; Anktiva), an intravesical immunotherapy approved for select patients with non–muscle invasive bladder cancer (NMIBC).

The agency determined that both a direct-to-consumer (DTC) television advertisement and a podcast with founder and executive chairman Patrick Soon-Shiong, MD, overstated efficacy, omitted risk information, and suggested unapproved uses, raising concerns about patient safety and regulatory compliance.¹

The FDA’s Office of Prescription Drug Promotion (OPDP) concluded that the materials misbranded the drug under the Federal Food, Drug, and Cosmetic Act by implying that Anktiva could cure or prevent cancer broadly, despite its only approved indication being for a specific type of NMIBC. The agency emphasized that such claims are particularly concerning in oncology, with cancer being a significant public health issue affecting a particularly vulnerable patient population.

NAI received FDA approval in 2024 for use in combination with BCG for adult patients with BCG-unresponsive NMIBC with carcinoma in situ (CIS), with or without papillary tumors. The approval was based on findings from the phase 2/3 QUILT-3.032 trial, a single-arm, multicenter study evaluating intravesical NAI plus BCG.²

In that study, 77 patients with BCG-unresponsive high-risk NMIBC with CIS with or without Ta/T1 papillary disease achieved a complete response (CR) rate of 62% (95% CI, 51 to 73). Among responders, 58% maintained response for at least 12 months, and 40% for at least 24 months.

However, the single-arm design limits interpretation of time-to-event end points such as disease-free survival (DFS), as no comparator arm was included. The FDA warning letter reiterates this limitation, noting that claims suggesting durable cure or prevention are not supported by the available data. Additionally, a separate cohort evaluating Anktiva monotherapy in this setting was discontinued early due to futility. As such, the FDA noted that they are aware of data that would support efficacy of NAI alone for NMIBC.

According to the FDA, the promotional materials included several categories of violations:

• Overstated efficacy: Statements implying that Anktiva could “cure cancer” or prevent recurrence across all patients were deemed unsupported by clinical evidence.
• Unapproved indications: The materials suggested efficacy in “all cancers,” including lung cancer and post–checkpoint inhibitor settings, which fall outside the drug’s approved indication.
• Incorrect administration claims: The drug was described as a “single jab” or subcutaneous injection, despite being approved exclusively for intravesical use.
• Mischaracterization of mechanism: References to Anktiva as a “cancer vaccine” were deemed inaccurate; the agent is an IL-15 receptor agonist that stimulates NK, CD8+, and memory T-cell activity.
• Omission of risk information: The podcast reportedly contained no safety disclosures, and the TV advertisement minimized risk presentation relative to benefit claims.

The FDA also cited procedural violations, including failure to submit the podcast under Form FDA 2253 at the time of initial publication or dissemination.

Company response

In a public statement,³ ImmunityBio reported that it has submitted a formal response to the FDA and initiated corrective actions. The company stated that the cited podcast has been removed from its website and that it has requested removal from third-party platforms. Additionally, the company indicated that the television advertisement referenced in the warning letter was never broadcast.

ImmunityBio also described implementation of enhanced Promotional Review Committee processes, executive training, and external regulatory oversight to improve compliance. The company is also working with its legal and regulatory teams to complete “a comprehensive review of all promotional materials and external communications claims.”

The company characterized the statements made in the podcast as “aspirational and forward-looking” commentary on its broader immunotherapy platform rather than promotional claims tied to the approved indication. Specifically, ImmunityBio noted that references to multiple oncology indications were intended to focus on the investigational applications of the IL-15 platform, and references to “cancer vaccines” were intended to describe the mechanistic potential of immunotherapies that induce memory T cells.

“ImmunityBio takes promotional compliance with the utmost seriousness,” said Richard Adcock, President and CEO of ImmunityBio, in a news release from the company.³ “We are dedicated to maintaining a clear distinction between our investigational pipeline aspirations and the promoted indications for our approved therapies. We believe our substantive remedial actions and enhanced internal protocols address the Agency’s concerns.”

REFERENCES

1. Warning letter: ImmunityBio, Inc. US Food & Drug Administration. March 13, 2026. Accessed April 6, 2026. https://www.fda.gov/inspections-compliance-enforcement-and-criminal-investigations/warning-letters/immunitybio-inc-725468-03132026

2. Chamie K, Chang SS, Kramolowsky E, et al. IL-15 Superagonist NAI in BCG-Unresponsive Non-Muscle-Invasive Bladder Cancer. NEJM Evid. 2023;2(1):EVIDoa2200167. doi:10.1056/EVIDoa2200167

3. ImmunityBio Addresses FDA Correspondence and Reaffirms Commitment to Advertising Compliance. News release. ImmunityBio. April 6, 2026. Accessed April 6, 2026. https://www.businesswire.com/news/home/20260406166524/en/ImmunityBio-Addresses-FDA-Correspondence-and-Reaffirms-Commitment-to-Advertising-Compliance