For Medical Professionals

Supply Interruption of ONTAK® (denileukin diftitox) Drug Product

Sometime during the week of June 27, 2011, a supply interruption of ONTAK Drug Product occurred. Eisai has encountered challenges in the production of ONTAK and is actively working to resolve the manufacturing issue.

A trend in certain product characteristics, including out-of-specification results, requires an in-depth process review prior to releasing any further lots. The timing of this process review and any resulting production or testing modifications will result in a supply interruption. We cannot estimate the length of the supply interruption at this time.

Updates regarding product availability will be posted on http://www.ONTAK.com.

If any of your patients are currently being treated with ONTAK, please communicate with them about the anticipated supply interruption.

Eisai has developed an Access Program (Compassionate Use Program) for patients who are currently receiving ONTAK. Please call Eisai Medical Services at 1-888-422-4743 for specific details on the program including the protocol and informed consent. Please discuss this program as an option for your patients currently receiving ONTAK, along with the potential risks and benefits of participating in the program. Only patients currently receiving ONTAK may participate in the program, and physicians may enroll patients in the Access Program only after appropriate Institutional Review Board review of the Access Program protocol and informed consent.

For more information please contact Eisai Medical Services for any questions about the company’s products at 1-888-422-4743. You may also check http://www.ONTAK.com for updates on availability.