ATA, AACE and TES respond to FDA postponement of workshop

March 19, 2004

Steven Galson, M.D.
Acting Director, Center for Drug Evaluation and Research
Food and Drug Administration
5600 Fishers Lane, HFD-240
Rockville, MD 20857

Dear Dr. Galson:

We are writing on behalf of our societies–the American Thyroid Association (ATA), The Endocrine Society (TES), and American Association of Clinical Endocrinologists (AACE) — to express our disappointment that FDA has postponed planning for the thyroxine therapeutic equivalence workshop, on which we had already begun working with your staff. We also want to share with you our deep concern that the agency has not had the opportunity to hear and consider thoroughly the views of the experts who guide clinical thinking about management of the 13 million Americans who take levothyroxine products.

Our societies understand that FDA wants first to resolve issues raised by the citizens’ petitions that have been filed by industry. At the same time, we feel strongly that the agency’s response to these petitions and approval of additional levothyroxine sodium products should be informed by the thoughtful discussion that had been planned for this workshop. This proposal for this meeting, which was made by your own CDER director, Dr. Woodcock, arose from our common recognition that the advice received by the agency at your March 13 Pharmacokinetic Advisory Committee was pharmacologically dogmatic and clinically uninformed. Dr. Woodcock herself was explicit at our September 15, 2003 meeting in expressing her disappointment with the clinical naiveté of the panel.

We had been heartened by the commitment that you made to plan and hold a workshop of sufficient depth and duration to address all of the relevant issues: bioequivalence testing baseline correction, optimal test subjects, and acceptable confidence limits; and TSH as a pharmacodynamic measure. We hope that FDA will follow through on its commitment to this meeting, and that the meeting will not become an empty exercise held after FDA has finalized decisions regarding these issues.

We urge FDA, as we did in our September 29, 2003 letter, to 1) suspend approval of new thyroxine formulations until these matters are resolved, and 2) not make final decisions regarding equivalence testing until you have heard from representatives of the real experts in this field— more than 4,600 clinical endocrinologist members of our societies–at the workshop that FDA itself proposed.

We look forward to hearing from you.

Yours truly,


Paul W. Ladenson, MD	E. Chester Ridgway, MD	Donald A. Bergman, MD
President-Elect	President	President
American Thyroid Association	Endocrine Society	American Association of Clinical Endocrinologists