ImmunityBio (IBRX) traded lower today as the market extended the risk-off reaction to the FDA’s recent promotional enforcement action involving ANKTIVA (nogapendekin alfa inbakicept-pmln). The warning letter focuses on promotional communications (including a TV ad and a podcast) that the agency said were false or misleading, keeping regulatory uncertainty elevated and pressuring sentiment. (fda.gov)

A key near-term focus is the FDA’s requirement that the company submit a written response within 15 working days of receipt of the warning letter, including an accounting of other promotional pieces with similar claims and a plan to discontinue or remediate such communications. With that compliance clock in view, traders are discounting the potential for ongoing scrutiny or additional corrective steps that could disrupt commercialization messaging. (fda.gov)

Separately, multiple law-firm notices have amplified attention on securities-fraud class action litigation tied to the same period surrounding the FDA action, with a stated lead-plaintiff motion deadline of May 26, 2026. While these notices don’t change fundamentals on their own, they can raise perceived headline risk and reinforce volatility for momentum-heavy biotech names. (globenewswire.com)