FDA Adds Boxed Warning to Takeda's Adzynma Over Risk of Neutralizing Antibodies
The FDA has issued a boxed warning for Adzynma, Takeda's enzyme replacement therapy, due to reports of neutralizing antibodies that can cause serious outcomes, including death.
4 reports on this incident · first at Aug 26, 2026, 4:40 p.m. ET
This recall is open. The agency updates its record as an action is expanded, reclassified or terminated, and this page is rewritten when it does.
We last searched for new coverage of this at Aug 26, 2026, 4:40 p.m. ET — checked 2h ago.
Earlier reports
Aug 26, 2026, 4:51 p.m. ET
FDA Adds Boxed Warning to Takeda's Adzynma Over Risk of Neutralizing Antibodies
The U.S. Food and Drug Administration has added a boxed warning to Adzynma, Takeda's enzyme replacement therapy for an ultra-rare clotting disorder, according to Medical Daily. The warning addresses the risk of neutralizing antibodies against ADAMTS13, with serious outcomes including death reported in patients treated with the drug.
The agency advises monitoring all patients closely for ADAMTS13 activity and development of ADAMTS13 neutralizing antibodies. Adzynma is the only approved enzyme replacement therapy for this condition.
Aug 26, 2026, 4:46 p.m. ET
FDA Adds Boxed Warning to Takeda's Adzynma Over Risk of Neutralizing Antibodies
The U.S. Food and Drug Administration has added a boxed warning to Adzynma, Takeda's enzyme replacement therapy for an ultra-rare clotting disorder, after reports of serious side effects, including death, according to Medical Daily.
The warning follows reports of neutralizing antibodies against ADAMTS13 in patients treated with the drug, which have been associated with serious outcomes, including death. The FDA advises monitoring all patients closely for ADAMTS13 activity and the development of neutralizing antibodies.
Adzynma is the only approved enzyme replacement therapy for the ultra-rare clotting disorder.
Aug 26, 2026, 4:40 p.m. ETFirst report
FDA Adds Boxed Warning to Takeda's Adzynma Over Risk of Neutralizing Antibodies
The U.S. Food and Drug Administration (FDA) has added a boxed warning to Adzynma, the only approved enzyme replacement therapy for an ultra-rare clotting disorder, according to a report from Medical Daily. The warning is based on reports of neutralizing antibodies against ADAMTS13, which have led to serious outcomes, including death, in patients treated with the drug.
The FDA has instructed healthcare providers to monitor all patients closely for ADAMTS13 activity and the development of ADAMTS13 neutralizing antibodies. The drug is manufactured by Takeda.
The cause of the adverse events has not been determined, and the FDA's action is a precautionary measure. The boxed warning is the agency's most prominent warning level.
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- Version 126 Aug 2026, 20:52current
First published.
- Version 126 Aug 2026, 20:40current
First published.
- Version 126 Aug 2026, 20:46current
First published.
- Version 126 Aug 2026, 20:51current
First published.
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