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                                                                   EXHIBIT 10.38


                                  MYOGEN, INC.

                        2003 EMPLOYEE STOCK PURCHASE PLAN
                                    OFFERING

            ADOPTED BY THE BOARD OF DIRECTORS AS OF FEBRUARY 1, 2005


         In this document, capitalized terms not otherwise defined shall have
the same definitions of such terms as in the Myogen, Inc. 2003 Employee Stock
Purchase Plan.

1.       GRANT; OFFERING DATE.

         (A) The Board hereby authorizes a series of Offerings pursuant to the
terms of this Offering document.

         (B) The Offering shall begin on February 1, 2005 and shall end on
January 31, 2007, unless terminated earlier as provided below. Thereafter, an
Offering shall begin on the day after the last Purchase Date of the immediately
preceding Offering. The first day of an Offering is that Offering's "OFFERING
DATE." Each Offering shall be twenty-four (24) months in duration, with four (4)
Purchase Periods each of which shall be approximately six (6) months in length.
Except as provided below, a "PURCHASE DATE" is the last day of a Purchase Period
or of an Offering, as the case may be. The Offering shall consist of four (4)
Purchase Periods, with the first Purchase Period ending on July 31, 2005, the
second Purchase Period ending on January 31, 2006, the third Purchase Period
ending on July 31, 2006, and the fourth Purchase Period ending on January 31,
2007.

         (C) Notwithstanding the foregoing: (i) if any Offering Date falls on a
day that is not a Trading Day, then such Offering Date shall instead fall on the
next subsequent Trading Day, and (ii) if any Purchase Date falls on a day that
is not a Trading Day, then such Purchase Date shall instead fall on the
immediately preceding Trading Day.

         (D) Prior to the commencement of any Offering, the Board may change any
or all terms of such Offering and any subsequent Offerings. The granting of
Purchase Rights pursuant to each Offering hereunder shall occur on each
respective Offering Date unless prior to such date (i) the Board determines that
such Offering shall not occur, or (ii) no shares of Common Stock remain
available for issuance under the Plan in connection with the Offering.

         (E) If the Company's accountants advise the Company that the accounting
treatment of purchases under the Plan has changed in a manner that the Company
determines is detrimental to its best interests, then each Offering hereunder
that is then ongoing shall terminate as of the next Purchase Date (after the
purchase of stock on such Purchase Date) under such Offering.

         (F) Notwithstanding anything in this Section 1 to the contrary, if on
the first day of a new Purchase Period during the Offering the Fair Market Value
of a share of Common Stock is less than it was on the Offering Date for that
Offering, then that Offering shall immediately terminate and that day shall
become the Offering Date of a new Offering. Eligible Employees


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in the terminated Offering shall automatically be enrolled in the new Offering
that starts on such day.

2.       ELIGIBLE EMPLOYEES.

         (A) Each Employee of the Company or of a Subsidiary on the Offering
Date of an Offering hereunder (an "ELIGIBLE EMPLOYEE"), shall be granted a
Purchase Right on the Offering Date of such Offering.

         (B) Notwithstanding the foregoing, the following Employees shall not be
Eligible Employees or be granted Purchase Rights under an Offering:

             (I) part-time or seasonal Employees whose customary employment is
less than twenty (20) hours per week or less than five (5) months per calendar
year;

             (II) five percent (5%) stockholders (including ownership through
unexercised and/or unvested stock options) as described in Section 6(c) of the
Plan; or

             (III) Employees in jurisdictions outside of the United States if,
as of the Offering Date of the Offering, the grant of such Purchase Rights would
not be in compliance with the applicable laws of any jurisdiction in which the
Employee resides or is employed.

         (C) Notwithstanding the foregoing, each person who first becomes an
Eligible Employee during an Offering shall receive, on the day after the first
Purchase Date during that Offering, which occurs after the date such person
becomes an eligible employee, a Purchase Right under such Offering, which
Purchase Right shall thereafter be deemed to be a part of the Offering. Such
Purchase Right shall have the same characteristics as any Purchase Rights
originally granted under the Offering except that:

             (I) the date on which such Purchase Right is granted shall be the
"Offering Date" of such Purchase Right for all purposes except for the
application of the provision of Section 1(f) above (the application of which
shall be determined only by using the Offering Date of the ongoing Offering),
including determination of the exercise price of such Purchase Right; and

            (II) the Offering for such Purchase Right shall begin on its
Offering Date and end coincident with the end of the ongoing Offering.

3.       PURCHASE RIGHTS.

         (A) Subject to the limitations herein and the Plan, unless a lower
percentage has been set by the Board or a committee thereof prior to the
commencement of the Offering, a Participant's Purchase Right shall permit the
purchase of the number of shares of Common Stock purchasable with up to twenty
percent (20%) of such Participant's Earnings paid during the period of such
Offering beginning immediately after such Participant first commences
participation; provided, however, that no Participant may have more than twenty
percent (20%) of such Participant's Earnings applied to purchase shares of
Common Stock under all ongoing


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Offerings under the Plan and all other plans of the Company and Related
Corporations that are intended to qualify as Employee Stock Purchase Plans.

         (B) For Offerings hereunder, "EARNINGS" means the base compensation
paid to an Eligible Employee, including all salary, wages and overtime pay
(including amounts elected to be deferred by such Eligible Employee, that would
otherwise have been paid, under any cash or deferred arrangement or other
deferred compensation program established by the Company or a Related
Corporation), but excluding commissions, bonuses, and other remuneration paid
directly to such Eligible Employee, profit sharing, the cost of employee
benefits paid for by the Company or a Related Corporation, education or tuition
reimbursements, imputed income arising under any Company or Related Corporation
group insurance or benefit program, traveling expenses, business and moving
expense reimbursements, income received in connection with stock options,
contributions made by the Company or a Related Corporation under any employee
benefit plan, and similar items of compensation.

         (C) Notwithstanding the foregoing, the maximum number of shares of
Common Stock that a Participant may purchase on any Purchase Date in an Offering
shall be such number of shares as has a Fair Market Value (determined as of the
Offering Date for such Offering) equal to (x) $25,000 multiplied by the number
of calendar years in which the Purchase Right under such Offering has been
outstanding at any time, minus (y) the Fair Market Value of any other shares of
Common Stock (determined as of the relevant Offering Date with respect to such
shares) that, for purposes of the limitation of Section 423(b)(8) of the Code,
are attributed to any of such calendar years in which the Purchase Right is
outstanding. The amount in clause (y) of the previous sentence shall be
determined in accordance with regulations applicable under Section 423(b)(8) of
the Code based on (i) the number of shares previously purchased with respect to
such calendar years pursuant to such Offering or any other Offering under the
Plan, or pursuant to any other Company or Related Corporation plans intended to
qualify as Employee Stock Purchase Plans, and (ii) the number of shares subject
to other Purchase Rights outstanding on the Offering Date for such Offering
pursuant to the Plan or any other such Company or Related Corporation Employee
Stock Purchase Plan.

         (D) The maximum aggregate number of shares of Common Stock available to
be purchased by all Participants under an Offering shall be the number of shares
of Common Stock remaining available under the Plan on the Offering Date. If the
aggregate purchase of shares of Common Stock upon exercise of Purchase Rights
granted under the Offering would exceed the maximum aggregate number of shares
available, the Board shall make a pro rata allocation of the shares available in
a uniform and equitable manner.

         (E) Notwithstanding the foregoing, the maximum number of shares of
Common Stock that a Participant may purchase on any Purchase Date during any
Offering shall not exceed Ten Thousand (10,000) shares.

4.       PURCHASE PRICE.

         The purchase price of shares of Common Stock under an Offering shall be
the lesser of: (i) eighty-five percent (85%) of the Fair Market Value of such




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shares of Common Stock on the applicable Offering Date, or (ii) eighty-five
percent (85%) of the Fair Market Value of such shares of Common Stock on the
applicable Purchase Date, in each case rounded up to the nearest whole cent per
share.

5.       PARTICIPATION.

         (A) If an Eligible Employee intends to participate in an Offering, such
Eligible Employee shall elect his or her payroll deduction percentage on such
enrollment form as the Company provides. The completed enrollment form must be
delivered to the Company prior to the Offering Date of the applicable Offering,
unless a later time for filing the enrollment form is set by the Company for all
Eligible Employees with respect to a given Offering. Payroll deduction
percentages must be expressed in whole percentages of Earnings, with a minimum
percentage of one percent (1%) and a maximum percentage of twenty percent (20%).
Contributions may be made only by way of payroll deductions.

         (B) A Participant may increase or decrease (including a decrease to
zero percent (0%) his or her participation level at the beginning of each
Purchase Period and once during a Purchase Period. Any such increase or decrease
in participation level shall be made by delivering a notice to the Company or a
designated Subsidiary in such form as the Company provides at the beginning of
the Purchase Period or, with respect to the one change permitted during a
Purchase Period, prior to the ten (10) day period (or such shorter period of
time as determined by the Company and communicated to Participants) immediately
preceding the next Purchase Date of the Purchase Period for which it is to be
effective.

         (C) A Participant may withdraw from an Offering and receive a refund of
his or her Contributions (reduced to the extent, if any, such Contributions have
been used to acquire shares of Common Stock for the Participant on any prior
Purchase Date) without interest, at any time prior to the end of the Offering,
excluding only each ten (10) day period immediately preceding a Purchase Date
(or such shorter period of time determined by the Company and communicated to
Participants), by delivering a withdrawal notice to the Company or a designated
Subsidiary in such form as the Company provides. A Participant who has withdrawn
from an Offering shall not again participate in such Offering, but may
participate in subsequent Offerings under the Plan in accordance with the terms
of the Plan and the terms of such subsequent Offerings.

         (D) Notwithstanding the foregoing or any other provision of this
Offering document or of the Plan to the contrary, neither the enrollment of any
Eligible Employee in the Plan nor any forms relating to participation in the
Plan shall be given effect until such time as a registration statement covering
the registration of the shares under the Plan that are subject to the Offering
has been filed by the Company and has become effective.

         (E) Notwithstanding the foregoing or any other provision of this
Offering document or of the Plan to the contrary, each Eligible Employee who is
employed on the Offering Date automatically shall be enrolled in the Offering,
with a Purchase Right to purchase up to the number of shares of Common Stock
that are purchasable with 20% of the Eligible Employee's Earnings, subject to
the limitations set forth in Section 3 above. Each Eligible Employee shall be
provided a certain period of time, as determined by the Company in its sole
discretion, within which to elect to authorize payroll deductions for the
purchase of shares during the Offering



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(which may be for a percentage that is less than or equal to 20% of the Eligible
Employee's Earnings, including zero percent (0%)).

6.       PURCHASES.

         Subject to the limitations contained herein, on each Purchase Date,
each Participant's Contributions (without any increase for interest) shall be
applied to the purchase of whole shares, up to the maximum number of shares
permitted under the Plan and the Offering.

7.       NOTICES AND AGREEMENTS.

         Any notices or agreements provided for in an Offering or the Plan shall
be given in writing, in a form provided by the Company, and unless specifically
provided for in the Plan or this Offering, shall be deemed effectively given
upon receipt or, in the case of notices and agreements delivered by the Company,
five (5) days after deposit in the United States mail, postage prepaid.

8.       EXERCISE CONTINGENT ON STOCKHOLDER APPROVAL.

         The Purchase Rights granted under an Offering are subject to the
approval of the Plan by the stockholders of the Company as required for the Plan
to obtain treatment as an Employee Stock Purchase Plan.

9.       OFFERING SUBJECT TO PLAN.

         Each Offering is subject to all the provisions of the Plan, and the
provisions of the Plan are hereby made a part of the Offering. The Offering is
further subject to all interpretations, amendments, rules and regulations which
may from time to time be promulgated and adopted pursuant to the Plan. In the
event of any conflict between the provisions of an Offering and those of the
Plan (including interpretations, amendments, rules and regulations which may
from time to time be promulgated and adopted pursuant to the Plan), the
provisions of the Plan shall control.




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