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Exhibit 10.33 MYOGEN, INC. 2003 EMPLOYEE STOCK PURCHASE PLAN
OFFERING Adopted by the Board of Directors July 8, 2004 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. Grant; Offering Date.  (a)
    
    The Board hereby authorizes a
series of Offerings pursuant to the terms of this
Offering document.(b)
    
    The Initial Offering shall begin
on August 1, 2004 and shall end on July 31, 2006,
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 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 Initial Offering
shall consist of four (4) Purchase Periods, with the
first Purchase Period ending on January 31, 2005, the
second Purchase Period ending on July 31, 2005, the
third Purchase Period ending on January 31, 2006, and
the fourth Purchase Period ending on July 31, 2006.(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.




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Eligible Employees in the terminated Offering shall
automatically be enrolled in the new Offering that
starts on such day. Eligible Employees.  (g)
    
    Each Employee of the Company or
of a Subsidiary incorporated in the United States on
the Offering Date of an Offering hereunder who has
been an Employee of the Company or a Subsidiary for a
continuous period ending on the applicable Offering
Date of at least ninety (90) days (an Eligible
Employee), shall be granted a Purchase Right on the
Offering Date of such Offering.(h)
    
    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.  (i)
    
    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. Purchase Rights.  (j)
    
    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 Offerings under the
Plan and all other plans of the Company and Related
Corporations that are intended to qualify as Employee
Stock Purchase Plans.




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(k)
    
    For Offerings hereunder,
Earningsmeans the base compensation paid to an
Eligible Employee, including all salary and wages
(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
overtime pay, 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.(l)
    
    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.(m)
    
    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.(n)
    
    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. 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
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.




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Participation.  (o)
    
    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%). Except as provided in paragraph (e)
below with respect to the Initial Offering,
Contributions may be made only by way of payroll
deductions.(p)
    
    A Participant may increase or
decrease his or her participation level during a
Purchase Period. A Participant may increase or
decrease (including a decrease to zero percent (0%))
his or her participation level only 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 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.(q)
    
    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.(r)
    
    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.(s)
    
    Notwithstanding the foregoing or
any other provision of this Offering document or of
the Plan to the contrary, with respect to the Initial
Offering only, each Eligible Employee who is employed
on the Initial Offering Date automatically shall be
enrolled in the Initial 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(c)-(f) 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 Initial Offering
(which may be for a percentage that is less than or
equal to 20% of the Eligible Employees Earnings).




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If an Eligible Employee elects not to authorize
payroll deductions, then the Eligible Employee shall
not purchase any shares of Common Stock during the
Initial Offering. After the end of the Initial
Offering, in order to participate in any subsequent
Offerings, an Eligible Employee must enroll and
authorize payroll deductions prior to the
commencement of the Offering, in accordance with
paragraph (a) above; provided, however,that once an
Eligible Employee enrolls in an Offering and
authorizes payroll deductions (including in
connection with the Initial Offering), the Eligible
Employee automatically shall be enrolled for all
subsequent Offerings until he or she elects to
withdraw from an Offering pursuant to paragraph (c)
above or terminates his or her participation in the
Plan. 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. 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. Exercise Contingent on Stockholder Approval.  (t)
    
    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. 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.