Mirapex

RE: Mirapex (pramipexole dihydrochloride) tablets

04-07-05

The purpose of this letter is to advise you that effective May 1, 2005, Boehringer Ingelheim Pharmaceuticals, Inc. (BIPI), will be the exclusive promoter of Mirapex (pramipexole) in the US. As such, BIPI's newly expanded Neurology sales force will be responsible for all field support on this brand; the Pfizer field force will no longer be providing field support for the product.

This was a joint decision made by BIPI and Pfizer. The companies have been working together to ensure that the transition occurs without disruption to patients, caregivers and healthcare professionals. The change will have no impact on the availability of your retail stocking or sales of MIRAPEX. Please note that the MIRAPEX label will change and the wording "co-marketed by Boehringer Ingelheim Pharmaceuticals, Inc. and Pfizer Inc," will be removed.

We are excited about this transition to our expanded Neurology sales force. It is our strong belief that this expansion will help assure the continued growth of the MIRAPEX brand. We look forward to working with our retail partners to ensure that this transition goes smoothly.

Regards,

Robert W. Belknap

Executive Director, Trade Relations

Boehringer Ingelheim Pharmaceuticals, Inc.