CSL Behring GmbH – FDA Warning Letter

The FDA issued a warning letter to CSL Behring on September 9, 2025, concerning a Direct-to-Consumer (DTC) television advertisement for HIZENTRA, a subcutaneous immune globulin. The advertisement, titled "Live in Strength: Supermarket," was found to overstate the drug"s effectiveness and minimize its safety risks, thereby misbranding HIZENTRA in violation of the Federal Food, Drug, and Cosmetic Act (FD&C Act). The ad misleadingly suggested that HIZENTRA provides comprehensive protection against germs and restores the immune system, which exceeds its approved indications for primary humoral immunodeficiency and chronic inflammatory demyelinating polyneuropathy.

The FDA noted that the risk information was not presented as prominently as the benefits, with distracting visuals and small, inconspicuous text undermining the communication of potential risks. The FDA"s Center for Biologics Evaluation and Research had previously advised CSL Behring to revise the ad, but the final version failed to address these concerns.

CSL Behring is required to take immediate corrective action, including ceasing misleading promotional communications. They must respond within 15 working days, detailing how they will address the violations and provide a plan for corrective communications to the affected audience. Failure to comply may result in legal actions such as seizure or injunction.