EXHIBIT (A)(7)

                          [ESPERIOR THERAPEUTICS LOGO]

                                                        Date

Dear Stockholder:

     We are pleased to report that Esperion Therapeutics, Inc. has entered into
a merger agreement with Pfizer Inc. that provides for the acquisition of
Esperion at a price of $35.00 per share in cash. Under the terms of the proposed
transaction, Enzo Acquisition Corp., a wholly owned subsidiary of Pfizer, has
commenced a tender offer today for all of the outstanding shares of Esperion
common stock at $35.00 per share in cash. The tender offer is conditioned upon,
among other things, at least a majority of Esperion's outstanding shares of
Common Stock on a fully-diluted basis being tendered and the termination of any
waiting periods under applicable antitrust laws. Following the completion of the
tender offer, Enzo Acquisition Corp. will be merged with and into Esperion and
all shares of Esperion's common stock not purchased in the tender offer (other
than those owned by Esperion, Pfizer or Enzo Acquisition Corp. or by holders who
have perfected their appraisal rights) will be converted into the right to
receive $35.00 per share in cash in the merger.

     YOUR BOARD OF DIRECTORS HAS UNANIMOUSLY APPROVED THE TENDER OFFER AND THE
MERGER AGREEMENT, HAS UNANIMOUSLY DECLARED THAT THE MERGER IS ADVISABLE AND THAT
THE TERMS OF THE OFFER AND MERGER ARE FAIR TO, AND IN THE BEST INTERESTS OF,
ESPERION AND ITS STOCKHOLDERS, AND UNANIMOUSLY RECOMMENDS THAT ITS STOCKHOLDERS
ACCEPT THE OFFER AND TENDER THEIR SHARES OF COMMON STOCK PURSUANT TO THE OFFER.

     In addition to the Solicitation/Recommendation Statement that accompanies
this letter, also enclosed is Enzo Acquisition Corp.'s Offer to Purchase and
related materials, including a Letter of Transmittal for use in tendering
shares. These documents set forth the terms and conditions of the tender offer.
We urge you to read the enclosed information and consider it carefully before
making your decision to tender your common shares.

     The directors, management, and employees of Esperion thank you for the
support you have given Esperion.

                                          Sincerely,

                                              /s/ ROGER S. NEWTON, PH.D.
                                          --------------------------------------
                                           President & Chief Executive Officer