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                                                                   EXHIBIT 10.42

                          ESPERION THERAPEUTICS, INC.

                             1998 STOCK OPTION PLAN
                      (Amended, Effective April 18, 2002)


1.       PURPOSE

         The purpose of the Esperion Therapeutics, Inc. 1998 Stock Option Plan
(the "Plan') is to further the growth and success of Esperion Therapeutics, Inc.
(the "Company") by attracting and retaining the services of directors, officers,
selected employees, consultants and advisors by enabling them to acquire shares
of the Company's Common Stock, par value $.001 per share (the "Common Stock").
Except where the context otherwise requires, the term "Company" shall include
the parent corporation and all subsidiary corporations, if any, of the Company
as defined in Sections 424(e) and 424(f) of the Internal Revenue Code of 1986,
as amended (the "Code").

2.       TYPES OF OPTIONS.

         Options granted under the Plan may be either "incentive stock options"
("ISOs"), intended to qualify as such under the provisions of Section 422 of the
Code, or "non-qualified stock options" ("NQOs") not intended to qualify as ISOs
under Section 422 of the Code.

3.       ADMINISTRATION.

         (a)      Board of Directors/Committee.

         Options under the Plan shall be granted, and the Plan shall be
initially administered, by the Board of Directors of the Company (the "Board")
and, upon designation by the Board, by a committee (the "Committee") consisting
of two or more members of the Board who are "outside directors" as defined under
section 162(m) of the Code and "non-employee directors" as defined under Rule
16b-3 under the Securities Exchange Act of 1934, as amended (the "Exchange
Act"). The members of the Committee shall be appointed, and may be removed at
any time with or without cause, by resolution adopted by the Board. Any vacancy
on the Committee, whether due to action of the Board or any other cause, shall
be filled by resolution adopted by the Board. The Committee may delegate
authority to one or more subcommittees as it deems appropriate, which must
consist of two or more persons who are both "outside directors" as defined under
section 162(m) of the Code and "non-employee directors" as defined under Rule
16b-3 under the Exchange Act. To the extent that a subcommittee administers the
Plan, references in the Plan to "Committee" shall be deemed to refer to the
subcommittee.

         (b)      Procedures.

         The Committee shall select from among its members a Chairman and may
adopt such rules and regulations as it shall deem appropriate concerning the
holding of meetings and the administration of the Plan. A majority of the entire
Committee shall constitute a quorum and the action of a majority of the members
of the Committee present at a meeting at which a quorum is present, or an action
approved in writing by all of the members of the Committee, shall be the act of
the Committee.



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         (c)      Interpretation.

         The Committee shall have full power and authority to interpret the
provisions of the Plan and any Option Agreement (as defined in Section 6(c)
below), to prescribe, amend and rescind rules and regulations relating to the
Plan and to resolve all questions arising under the Plan. All decisions of the
Committee shall be conclusive and binding on all participants in the Plan.

         (d)      Delegation of Authority

         Notwithstanding the foregoing, the Committee may delegate to either, or
both, of the Chief Executive Officer and the Chief Financial Officer of the
Company the authority to make grants under the Plan to employees, consultants
and advisors of the Company and its subsidiaries who are, at the time of the
grant, not subject to the restrictions of section 16(b) of the Exchange Act and
not expected to be subject to the limitations of section 162(m) of the Code. The
grant of authority under this Subsection 3(d) shall be subject to such
conditions and limitations as may be determined by the Committee.

4.       SHARES OF STOCK SUBJECT TO THE PLAN.

         (a)      Number of Shares.

         Subject to the provisions of Section 11 below (relating to adjustments
upon changes in capital structure), the number of shares of Common Stock
available for sale upon exercise of options granted under the Plan shall not
exceed 1,784,575 shares. If and to the extent that options granted under the
Plan terminate, expire or are cancelled without having been fully exercised, new
options may be granted under the Plan with respect to the shares of Common Stock
covered by the unexercised portion of such terminated, expired or cancelled
options, all of which may be granted as ISOs.

         (b)      Character of Shares.

                  The shares of Common Stock issuable upon exercise of an option
granted under the Plan may be (i) authorized but unissued shares of Common
Stock, (ii) shares of Common Stock held in the Company's treasury, or (iii) a
combination of both.

         (c)      Reservation of Shares.

         The number of shares of Common Stock reserved by the Company for
issuance under the Plan shall at no time be less than the maximum number of
shares which may be purchased at any time pursuant to outstanding options.

5.       ELIGIBILITY

                  Options may be granted under the Plan only to Persons who are
directors, officers, employees or advisors to the Company at the time of grant.
Options granted to officers and employees of the Company shall be, in the
discretion of the Committee, either ISOs or NSOs, and options granted to
directors who are not employees of the Company and to consultants and advisors
shall be NSOs. Notwithstanding anything herein to the contrary, ISOs



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shall only be granted to those persons who qualify as an employee under Section
3401(c) of the Code.

6.       GRANT OF OPTIONS

         (a)      General.

         Options may be granted under the Plan at any time and from time to time
on or prior to the Expiration Date (as defined in Section 15 below). Subject to
the provisions of the Plan, the Committee may, in its discretion, determine.

         (i) the persons (from among the class of persons eligible under Section
5 above to receive options under the Plan) to whom options shall be granted (the
"Optionees");

         (ii) the time or times at which options shall be granted;

         (iii) the number of shares subject to each option;

         (iv)  the Option Price (as defined in Section 7 below) of the shares
subject to each option, which price, in the case of ISOs, shall be not less than
the minimum specified in Section 7 below;

         (v) the time or times when each option shall become exercisable and the
duration of the exercise period; and

         (vi) any restrictions on the sale of, and any repurchase rights with
respect to, shares purchased upon exercise of an option, as contemplated by
Section 13 below.

         (b)      Date of Grant.

         The date of grant of an option under the Plan shall be the date on
which the Committee approves the grant.

         (c)      Option Agreements.

         Each option granted under the Plan shall be designated as an ISO or an
NSO and shall be subject to the terms and conditions applicable to ISOs or NSOs
(as the case may be) set forth in the Plan, and each option shall be evidenced
by a written agreement (an "Option Agreement"), containing such terms and
conditions, not inconsistent with the Plan, as the Committee may, in its
discretion, determine. Each Option Agreement shall be executed by the Company
and the Optionee. Option Agreements may differ among Optionees.

         (d)      No Evidence of Employment.

         Neither the grant of an option nor any provision of the Plan or any
Option Agreement shall confer upon any Optionee any right with respect to the
continuation of his or her employment by, or his or her consulting or advisory
relationship to, the Company or interfere in any way with the right of the
Company at any time to terminate such employment or relationship





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or, in the case of employees (including officers), to increase or decrease the
compensation of the Optionee from the rate in existence at the time of the grant
of an option.

7.       OPTION PRICE.

         The price (the "Option Price") at which each share of Common Stock
subject to an option granted under the Plan may be purchased shall be determined
by the Committee at the time the option is granted; provided, however, that in
the case of an ISO, such Option Price shall in no event be less than one hundred
percent (100%) of the fair market value of such share of Common Stock at the
time of grant, as determined by the Committee and, in the case of a ten percent
(10%) owner (see Section 8(c) below, such Option Price shall be at least one
hundred ten percent (110%) of the fair market value of the stock subject to such
options.

8.       EXERCISE OF OPTIONS.

         (a)      General.

         Each option shall be exercisable, in whole or in part, at such time or
times, or within such period or periods, or upon the occurrence of such event or
events, as shall be determined by the Committee and set forth in the Option
Agreement evidencing such option. If an option is not at the time of grant
immediately exercisable full, the Committee may (i) in the Option Agreement
evidencing such option provide for the acceleration of the exercise date or
dates of such option, in whole or in part, upon the occurrence of specified
events, or (ii) at any time prior to the complete expiration of an option,
accelerate, in whole or in part, the exercise date or dates of such option.

         (b)      Restrictions on Exercise.

         (i) No option by its terms shall be exercisable after the expiration of
ten years from the date such option is granted.

         (ii) No option may be exercised at a time when the exercise thereof or
the issuance or transfer of shares upon such exercise would, in the opinion of
the Committee, constitute a violation of any law, federal, state, local or
foreign, or any regulations thereunder, or the requirements of the New York
Stock Exchange or any other national securities exchange or market.

         (iii) The Committee, in its discretion, may require an Optionee to (A)
represent in writing that the shares of Common Stock to be received upon
exercise of an option are being acquired for his or her own account for
investment and not with a view to distribution thereof, nor with any present
intention of distributing the same, and (B) make such other representations and
warranties as are deemed necessary by counsel to the Company. Stock certificates
representing shares of Common Stock not registered under the Securities Act of
1933, as amended (the "1933 Act"), acquired upon the exercise of options shall
bear the following legend:

"THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE BEEN ACQUIRED FOR
INVESTMENT AND HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED, OR ANY STATE SECURITIES LAW. THESE SECURITIES



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MAY NOT BE SOLD OR TRANSFERRED IN THE ABSENCE OF SUCH REGISTRATION OR ANY
EXEMPTION THEREFROM UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY
APPLICABLE STATE SECURITIES LAW."

         (iv)     No option may be exercised for any fractional share.

         (c)      Limitation of Exercise of ISOs.

         To the extent that the aggregate fair market value (as determined by
the Committee as of the time the options with respect to such stock were
granted) of stock with respect to which options intended to be ISOs are
exercisable for the first time by an Optionee during any calendar year (under
all plans of the Company) exceeds $100,000, such options shall be treated as
NSOs. An ISO may not be granted to an individual who at the time an option is
granted, owns stock that has more than ten percent (10%) of the voting power of
all classes of stock of the Company ("ten percent (10%) owner"). An individual
is considered as owning stock, for purposes of the previous sentence, owned
directly or indirectly by or for his brothers, sisters, spouse, ancestors and
lineal descendants. An individual is also deemed to own stock held by a foreign
or domestic corporation, partnership, trust or estate for which the individual
is a shareholder, partner or beneficiary proportionately to his interest in the
corporation, partnership, trust or estate as a shareholder, partner or
beneficiary. Notwithstanding the foregoing prohibition on a "ten percent (10%)
owner," an ISO may be granted to a "ten percent (10%) owner" if (i) the ISO so
granted is not exercisable after the expiration of five (5) years from the date
of grant and (ii) the Option Price of such ISO is at least one hundred ten
percent (110%) of the fair market value of the stock subject to the ISO (as
provided in Section 7 hereof).

9.       PROCEDURE FOR EXERCISE.

         (a)      Payment.

         At the time an option is granted, the Committee shall, in its
discretion, specify one or more of the following forms of payment which may be
used by an Optionee upon exercise of his or her option:

         (i) cash or personal or certified check payable to the Company in an
amount equal to the aggregate Option Price of the shares with respect to which
the option is being exercised;

         (ii) stock certificates (in negotiable form) representing shares of
Common Stock having a fair market value (as determined by the Committee, which
determination, if the Common Stock is publicly traded, shall be based upon
market prices) equal to the aggregate Option Price of the shares with respect to
which the option is being exercised; provided, however, that this method of
payment may only be implemented if the Optionee has owned such shares of Common
Stock, beneficially and of record, for a period of at least six (6) consecutive
months immediately prior to exercise of his or her Option;

         (iii) cash proceeds equal to the aggregate Option Price of the shares
with respect to which the option is being exercised derived from the
simultaneous exercise of the option and sale of the underlying shares; or





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         (iv) a combination of any of such methods,

         (b)      Notice.

         An Optionee (or other person, as provided in Section 13(a) below) may
exercise an option, in whole or in part as provided in the Option Agreement
evidencing such option, by delivering a written notice (the "Notice") to the
Secretary of the Company. The Notice shall:

         (i) state that the Optionee elects to exercise the option and whether
the option being exercised is an ISO or an NSO;

         (ii) state the number of shares with respect to which the option is
being exercised (the "Optioned Shares");

         (iii) state the method of payment for the Optioned Shares (which method
must be available to the Optionee under the terms of his or her Option
Agreement) and, if applicable, that cash, a check and stock certificates (as the
case may be) are enclosed representing all or part of the aggregate Option Price
of such Optioned Shares;

         (iv) state the date upon which the Optionee desires to consummate the
purchase of the Optioned Shares (which date must be prior to termination of such
option under Section 10 below);

         (v) include any representation of the Optionee required pursuant to
Section 8(b)(iii) above,

         (vi) in the event the option is exercised pursuant to Section 13(a)
below by any person other than the Optionee, include evidence to the
satisfaction of the Committee of the right of such person to exercise the
option; and

         (vii) include such further provisions consistent with the Plan as the
Committee may from time to time require.

Within 30 days from the exercise date of any option, the Optionee shall deliver
to the Company a copy of any election filed by the Optionee with the Internal
Revenue Service under Section 83(b) of the Code.

         (c)      Issuance of Certificates.

         The Company shall issue a stock certificate in the name of the Optionee
(or such other person exercising the Option in accordance with the provisions of
Section 13(a) below) for the Optioned Shares as soon as practicable after
receipt of the notice and payment of the aggregate Option Price for such shares.
All such certificates, if so provided in the Option Agreement of such Optionee,
shall bear a legend in substantially the form set forth in Section 13(b) below,
and all certificates representing shares of Common Stock not registered under
the 1933 Act shall bear the legend set forth in Section 8(b)(iii) above. Neither
the Optionee nor any person exercising an option in accordance with the
provisions of Section 13(a) below shall have any privileges as a




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stockholder of the Company with respect to any shares of stock subject to an
option until such shares shall be registered on the books of the Company in the
name of such person.

10.      TERMINATION OF EMPLOYMENT; DISABILITY AND DEATH.

         (a)      General.

         Subject to the provisions of Section 8(b) above, the Committee may
determine the period or periods of time during which an Optionee may exercise an
option following (i) the termination by the Company, with or without cause, of
the Optionee's employment or other relationship with the Company, (ii) the
termination by the Optionee of any such relationship with the Company, or (iii)
the death or permanent and total disability of the Optionee (within the meaning
of Section 22(e)(3) of the Code). Such period or periods shall be set forth in
the Option Agreement evidencing each such option.

         (b)      Incentive Stock Options.

         No ISO may be exercised unless, at the time of exercise, the Optionee
is, and has continuously since the date of the grant of such ISO been, employed
by the Company, and, subject to the provisions of Section 8(b) above, the right
to exercise the unexercised portion of any ISO shall forthwith terminate upon
the first to occur of the following:

         (i) the expiration of not more than three months from the date of
termination of the Optionee's employment (other than a termination described in
subparagraph (ii) or (iii) below); provided, however, that if the Optionee shall
die or become permanently and totally disabled (within the meaning of Section
22(e)(3) of the Code) during such three-month period, the time of termination of
the unexercised portion of such option shall be determined in accordance with
subparagraph (ii) below;

         (ii) the expiration of not more than 12 months from the date of
termination of the Optionee's employment if such termination is due to such
Optionee's death or permanent and total disability (within the meaning of
Section 22(e)(3) of the Code);

         (iii) immediately upon the termination by the Company of the Optionee's
employment if such termination is for cause, as determined by the Committee, or
is otherwise attributable to a breach, as determined by the Committee, by the
Optionee of an employment agreement with the Company; or

         (iv) the expiration of such period of time or the occurrence of such
event as the Committee in its discretion may provide in the Option Agreement
evidencing such option.

11.      ANTIDULUTION.

         In the event the Common Stock is changed by reason of a stock split,
reverse stock split, stock dividend or recapitalization (exclusive of any future
public or private sales of Common Stock), or is converted into or exchanged for
other securities as a result of a merger, consolidation or reorganization in
which the Company is the surviving corporation, appropriate adjustments shall be
made, as determined by the Committee, in the terms of the outstanding





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options, or additional options may be granted under the Plan as shall be
equitable and appropriate, in order to make such outstanding options, as nearly
as may be practicable, equivalent to such options immediately prior to such
change. A corresponding adjustment changing the number and class of shares
allocated to, and the Option Price of, each option or portion thereof
outstanding at the time shall likewise be made. In the case of ISOs, no such
adjustment shall be made which would constitute a modification, extension or
renewal of such ISOs within the meaning of Section 424 of the Code.

12.      CORPORATE TRANSACTIONS.

         In the event the Common Stock is exchanged for securities, cash or
other property of any other corporation or entity as the result of a
reorganization, merger or consolidation in which the Company is not the
surviving corporation, the dissolution or liquidation of the Company, or the
sale of all or substantially all the assets of the Company, the Committee or the
Board of Directors of the Company may, in its discretion, as to outstanding
options (a) accelerate the exercise date or dates of such options pursuant to
Section 8(a) above, (b) upon written notice to the holders thereof, provided the
options have been accelerated pursuant to clause (a) above, terminate all such
options prior to the consummation of the transaction unless exercised within a
prescribed period, (c) provide for payment of an amount equal to the excess of
the fair market value, as determined by the Committee or such board, over the
Option Price of such shares as of the date of the transaction, in exchange for
the surrender of the right to exercise such options, or (d) provide for the
assumption of such options, or the substitution therefor of new options, by the
successor corporation or entity; provided, however, that with respect to ISOs
the requirements of Section 424 of the Code shall be met.

13.      RESTRICTIONS ON OPTIONS AND OPTIONED SHARES.

         (a)      Nonassignability of Option Rights.

         No option granted under this Plan shall be assignable or otherwise
transferable by the Optionee otherwise than by will or the laws of descent and
distribution, and shall be exercisable during the lifetime of the Optionee only
by him or her. In the event of the death of an Optionee, any option held by such
Optionee may thereafter be exercised by his or her representatives, executors or
administrators to the full extent to which such option was exercisable by the
Optionee at the time of his or her death.




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         (b)      Right of First Refusal; Right of First Offer.

         The Committee, in its discretion, may provide in any Option Agreement
that the Company or its designee shall have a right of first refusal or right of
first offer on the sale or transfer of any shares of Common Stock issued upon
exercise of the option subject to such Option Agreement, in the manner provided
therein, such right of first refusal or right of first offer to expire upon the
consummation of the initial public offering of the Common Stock pursuant to the
1933 Act. Any certificate representing shares of Common Stock issued pursuant to
an Option Agreement containing a right of first refusal or right of first offer
shall bear a legend in substantially the following form:

"THE TRANSFER OF THESE SECURITIES IS SUBJECT TO THE TERMS AND CONDITIONS OF A
STOCK OPTION AGREEMENT DATED AS OF ______________ AMONG ESPERION THERAPEUTICS,
INC., AND THE HOLDER OF RECORD OF THIS CERTIFICATE, AND NO SALE, ASSIGNMENT,
TRANSFER, PLEDGE, HYPOTHECATION OR OTHER DISPOSITION OF SUCH SECURITIES SHALL BE
VALID OR EFFECTIVE EXCEPT IN ACCORDANCE WITH SUCH AGREEMENT AND UNTIL SUCH TERMS
AND CONDITIONS HAVE BEEN FULFILLED. COPIES OF SUCH AGREEMENT MAY BE OBTAINED AT
NO COST BY WRITTEN REQUEST MADE BY THE HOLDER OF RECORD OF THIS CERTIFICATE TO
THE SECRETARY OF ESPERION THERAPEUTICS, INC."

14.      EFFECTIVE DATE.

         The Plan initially became effective on June 30, 1998. The Plan was most
recently amended on April 18, 2002.

15.      EXPIRATION AND TERMINATION.

         Except with respect to options then outstanding, the Plan shall expire
on the earliest to occur of (a) the tenth anniversary of the date on which the
Plan was adopted by the Board, (b) the tenth anniversary of the date on which
the Plan is approved by the stockholders of the Company, or (c) the date as of
which the Board, in its sole discretion, determines to terminate the Plan (the
"Expiration Date"). Any options outstanding as of the Expiration Date shall
remain in effect until they have been exercised or have terminated or expired by
their respective terms.

16.      AMENDMENT.

         The Board may at any time terminate, modify or amend the Plan;
provided, however, that if the approval of the stockholders of the Company shall
be required for any modification or amendment under Section 422 of the Code,
with respect to ISOs, or under Rule 16b-3 under the Securities Exchange Act of
1934, as amended with respect to shares of Common Stock registered under such
Act, such approval shall be obtained before such modification or amendment shall
become effective. No termination, modification or amendment of the Plan may,


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without the consent of an Optionee, adversely affect his or her rights under an
option previously granted to such Optionee.

17.      DISQUALIFYING DISPOSITIONS.

         If stock acquired upon exercise of an ISO granted under the Plan is
disposed of by the Optionee within two years from the date of grant of the ISO
or within one year after the transfer of the Optioned Shares to such Optionee (a
"disqualifying disposition"), such Optionee shall, immediately prior to such
disqualifying disposition, notify the Company in writing of the date and terms
of such disposition and provide such other information regarding the disposition
as the Company may reasonably require.

18.      TAXES.

         The Company may deduct from any cash payments due to an Optionee upon
exercise of an option any federal, state or local withholding taxes and
employment taxes relating thereto or, as a condition of delivery of any Optioned
Shares due upon such exercise, require the Optionee to remit, or, in appropriate
cases, agree to remit when due, an amount sufficient to satisfy such taxes;
provided, however, that, subject to the prior approval of the Committee, the
Optionee may, in whole or in part, satisfy such obligations (a) by permitting
the Company to withhold some or all of such Optioned Shares, or (b) by
delivering shares of Common Stock already owned by him or her. Shares so
withheld or delivered shall have a fair market value, as determined by the
Committee, equal to such obligations as of the date or dates the amounts of such
taxes are required to be determined. At the time of any disqualifying
disposition, the Optionee shall remit to the Company in cash the amount of any
such taxes relating to such disposition.

19.      CAPTIONS.

         The use of captions in the Plan or any Option Agreement is for the
convenience of reference only and shall not affect the meaning of any provision
of the Plan or such Option Agreement.

20.      GOVERNING LAW.

         The validity and construction of the Plan and the Option Agreements
shall be construed in accordance with and governed by the law of the State of
Delaware.









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