December 1, 1997

Dear Healthcare Professional:

As you will recall, on November 3 Warner-Lambert informed you about a company-initiatied change in the prescribing information on Rezulin (troglitazone) which specified the need for monitoring of liver function with patients taking the drug. Rezulin has already been prescribed for over 600,000 patients in the U.S. and heightened awareness following the earlier labeling change has, as expected, generated some additional reports of hepatic dysfunction. You may also hear media reports or receive patient inquiries related to Glaxo Wellcome's decision to temporarily suspend marketing of Romozin, their brand of troglitazone in the U.K., pending their review of worldwide safety data. Glaxo Wellcome recently received approval of Romozin in the U.K. and has experience with only 5,000 patients. This decision has no impact on the availability of Rezulin in the United States.

Warner-Lambert and the FDA have already completed a thorough review of the worldwide safety experience with Rezulin. On November 3 the FDA asked physicians for reports on additional adverse events. You will be reassured to know that the additional reports received since early November do not indicate a greater frequency of liver injury or potential for serious harm than had been previously estimated. Rezulin has been shown to be very effective in helping patients achieve glycemic control. The FDA continues to find a favorable benefit to risk relationship for Rezulin therapy in appropriately selected and monitored type 2 diabetics.

All therapies that are currently available to treat type 2 diabetes have potentially serious side effects. Warner-Lambert and the FDA, on the recent advice of experts, have decided to take additional steps in an effort to assure that the potential for this rare liver injury in Rezulin-treated patients is reduced to the absolute minimum. This has resulted in a new recommendation that liver enzymes and bilirubin levels of Rezulin-treated patients be measured at the start of therapy and monthly for the first six months of therapy. These tests should then be measured every two months for the remainder of the first year of therapy, and periodically thereafter.

We trust that this information will be helpful to you in continuing to effectively treat your type 2 diabetes patients with this important therapy. Should you have questions regarding these changes, or if you want to recieve a copy of full prescribing information for Rezulin, please call 1-800-223-0432 between 8:00 am and 8:00 pm EST Monday through Friday, or contact your Parke-Davis or Sankyo Parke Davis representative. Updated prescribing information for Rezulin will be sent to you as soon as it's available.

Sincerely,

William Sigmund II, M.D., M.H.S., F.A.C.C.
Vice President, Medical and Scientific Affairs

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