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                                                                   EXHIBIT 10.53




                                                               February 24, 2000


Dear Frank:

     On  behalf of Esperion Therapeutics, Inc. (the "Company"), I am pleased to
offer you a position with the Company. The following is an outline of the terms
of this offer:

     1.  The position offered is that of Director of Finance and Controller.

     2.  You shall be paid a monthly salary of $9,000.

     3.  You will be eligible for a bonus of up to 20%. We will provide you an
         advance on your first year's bonus of $10,000 within 2 weeks of your
         start date. The magnitude of the bonus, if any, will be determined by
         the Company's Board of Directors, based upon achievement of a series of
         mutually agreed upon performance milestones. A proposed series of
         milestones will be developed between you and the Vice President,
         Finance & CFO.

     3.  A benefits package will be provided to you which is equivalent to
         that offered to other similarly situated employees with the Company.
         This will include appropriate COBRA coverage for up to 1 year as
         determined between us.

     4.  Subject to meeting eligibility requirements, as incentive you will be
         granted an option to purchase 30,000 shares of the Company's common
         stock. The terms and conditions of this option shall be set forth in a
         Stock Option Agreement you will be required to execute.

     5.  In the event that your employment with the Company is terminated by the
         Company for reasons other than cause, you will be provided a severance
         package of 6 months of salary, with continuation of benefits during
         this period, and the Company will provide accelerated vesting such that
         25% of your as yet unvested stock options will immediately vest. In the
         event that your employment with the Company is terminated due to death
         or "permanent and total disability" (as such term may be defined by the
         Company's insurer) the company will provide accelerated vesting such
         that 25% of your yet unvested stock options will immediately vest. If
         you terminate your employment with the Company voluntarily, you will
         forfeit the severance package, as well as any of your unvested stock
         options. With respect to any vested options, in the event that you
         voluntarily terminate your employment

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         with the company, you will have 90 days to exercise these options, or
         otherwise they will be forfeited.

     6.  You will be required to execute the Company's standard forms of
         Non-Competition, as well as Confidentiality and Assignment Agreement.

     If  the terms of this offer are acceptable to you, please so indicate by
executing in the space provided below and fax, as well as mail (an original
copy) to the Company. Please respond to this offer within one week from the date
hereof. After this date (i.e. after March 2 , 2000), this offer may be withdrawn
at the discretion of the Company.

     Welcome to Esperion Therapeutics! We look forward to working with you to
bring new medicines to a world of unmet medical needs.


                                                   Sincerely,

                                                   /s/ Tim Mayleben

                                                   Tim Mayleben
                                                   Vice President, Finance & CFO



AGREED AND ACCEPTED:


/s/ Frank E. Thomas               2-26-00
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Name                                 Date