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                                                                   EXHIBIT 10.26

                            ALLOS THERAPEUTICS, INC.
                        2001 EMPLOYEE STOCK PURCHASE PLAN

               ADOPTED BY THE BOARD OF DIRECTORS FEBRUARY 28, 2001
                   APPROVED BY STOCKHOLDERS ____________, 2001


1.       PURPOSE.

         (a) The purpose of the Plan is to provide a means by which Employees of
the Company and certain designated Related Corporations may be given an
opportunity to purchase shares of the Common Stock of the Company.

         (b) The Company, by means of the Plan, seeks to retain the services of
such Employees, to secure and retain the services of new Employees and to
provide incentives for such persons to exert maximum efforts for the success of
the Company and its Related Corporations.

         (c) The Company intends that the Purchase Rights granted under the Plan
be considered options issued under an Employee Stock Purchase Plan.


2.       DEFINITIONS.

         (a) "BOARD" means the Board of Directors of the Company.

         (b) "CODE" means the Internal Revenue Code of 1986, as amended.

         (c) "COMMITTEE" means a committee appointed by the Board in accordance
with Section 3(c) of the Plan.

         (d) "COMMON STOCK" means the common stock of the Company.

         (e) "COMPANY" means Allos Therapeutics, Inc., a Delaware corporation.

         (f) "CORPORATE TRANSACTION" means the occurrence, in a single
transaction or in a series of related transactions, of any one or more of the
following events:

                  (i) a sale, lease, license or other disposition of all or
substantially all of the consolidated assets of the Company;

                  (ii) a sale or other disposition of at least ninety percent
(90%) of the outstanding securities of the Company;


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                  (iii) a merger, consolidation or similar transaction following
which the Company is not the surviving corporation; or

                  (iv) a merger, consolidation or similar transaction following
which the Company is the surviving corporation but the shares of Common Stock
outstanding immediately preceding the merger, consolidation or similar
transaction are converted or exchanged by virtue of the merger, consolidation or
similar transaction into other property, whether in the form of securities, cash
or otherwise.

         (g) "DIRECTOR" means a member of the Board.

         (h) "ELIGIBLE EMPLOYEE" means an Employee who meets the requirements
set forth in the Offering for eligibility to participate in the Offering,
provided that such Employee also meets the requirements for eligibility to
participate set forth in the Plan.

         (i) "EMPLOYEE" means any person, including Officers and Directors, who
is employed for purposes of Section 423(b)(4) of the Code by the Company or a
Related Corporation. Neither service as a Director nor payment of a director's
fee shall be sufficient to make an individual an Employee of the Company or a
Related Corporation.

         (j) "EMPLOYEE STOCK PURCHASE PLAN" means a plan that grants Purchase
Rights intended to be options issued under an "employee stock purchase plan," as
that term is defined in Section 423(b) of the Code.

         (k) "EXCHANGE ACT" means the Securities Exchange Act of 1934, as
amended.

         (l) "FAIR MARKET VALUE" means the value of a security, as determined in
good faith by the Board. If the security is listed on any established stock
exchange or traded on the Nasdaq National Market or the Nasdaq SmallCap Market,
the Fair Market Value of the security, unless otherwise determined by the Board,
shall be the closing sales price (rounded up where necessary to the nearest
whole cent) for such security (or the closing bid, if no sales were reported) as
quoted on such exchange or market (or the exchange or market with the greatest
volume of trading in the relevant security of the Company) on the relevant
determination date (or if the relevant determination date does not fall on a
Trading Day, the Trading Day prior to the relevant determination date), as
reported in The Wall Street Journal or such other source as the Board deems
reliable.

         (m) "OFFERING" means the grant of Purchase Rights to purchase shares of
Common Stock under the Plan to Eligible Employees.

         (n) "OFFERING DATE" means a date selected by the Board for an Offering
to commence.

         (o) "OFFICER" means a person who is an officer of the Company within
the meaning of Section 16 of the Exchange Act and the rules and regulations
promulgated thereunder.


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         (p) "PARTICIPANT" means an Eligible Employee who holds an outstanding
Purchase Right granted pursuant to the Plan.

         (q) "PLAN" means this Allos Therapeutics, Inc. 2001 Employee Stock
Purchase Plan.

         (r) "PURCHASE DATE" means one or more dates during an Offering
established by the Board on which Purchase Rights granted under the Plan shall
be exercised and as of which purchases of shares of Common Stock shall be
carried out in accordance with such Offering.

         (s) "PURCHASE PERIOD" means a period of time specified within an
Offering beginning on the Offering Date or on the next day following a Purchase
Date within an Offering and ending on a Purchase Date, at the end of which there
shall be purchased shares of Common Stock on behalf of Participants. An Offering
may consist of one or more Purchase Periods.

         (t) "PURCHASE RIGHT" means an option to purchase shares of Common Stock
granted pursuant to the Plan.

         (u) "RELATED CORPORATION" means any parent corporation or subsidiary
corporation, whether now or hereafter existing, as those terms are defined in
Sections 424(e) and (f), respectively, of the Code.

         (v) "SECURITIES ACT" means the Securities Act of 1933, as amended.

         (w) "TRADING DAY" means any day the exchange(s) or market(s) on which
shares of Common Stock are listed, whether it be any established stock exchange,
the Nasdaq National Market, the Nasdaq SmallCap Market or otherwise, is open for
trading.

3.       ADMINISTRATION.

         (a) The Board shall administer the Plan unless and until the Board
delegates administration to a Committee, as provided in Section 3(c). Whether or
not the Board has delegated administration, the Board shall have the final power
to determine all questions of policy and expediency that may arise in the
administration of the Plan.

         (b) The Board (or the Committee) shall have the power, subject to, and
within the limitations of, the express provisions of the Plan:

                  (i) To determine when and how Purchase Rights to purchase
shares of Common Stock shall be granted and the provisions of each Offering of
such Purchase Rights (which need not be identical).

                  (ii) To designate from time to time which Related Corporations
of the Company shall be eligible to participate in the Plan.

                  (iii) To construe and interpret the Plan and Purchase Rights
granted under the Plan, and to establish, amend and revoke rules and regulations
for the administration of the Plan. The Board, in the exercise of this power,
may correct any defect, omission or inconsistency in


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the Plan, in a manner and to the extent it shall deem necessary or expedient to
make the Plan fully effective.

                  (iv) To amend the Plan as provided in Section 15.

                  (v) Generally, to exercise such powers and to perform such
acts as it deems necessary or expedient to promote the best interests of the
Company and its Related Corporations and to carry out the intent that the Plan
be treated as an Employee Stock Purchase Plan.

         (c) The Board may delegate administration of the Plan to a Committee of
the Board composed of one (1) or more members of the Board. If administration is
delegated to a Committee, the Committee shall have, in connection with the
administration of the Plan, the powers theretofore possessed by the Board,
subject, however, to such resolutions, not inconsistent with the provisions of
the Plan, as may be adopted from time to time by the Board. The Board may
abolish the Committee at any time and revest in the Board the administration of
the Plan. If administration is delegated to a Committee, references to the Board
in this Plan and in the Offering document shall thereafter be deemed to be to
the Board or the Committee, as the case may be.

4.       SHARES OF COMMON STOCK SUBJECT TO THE PLAN.

         (a) Subject to the provisions of Section 14 relating to adjustments
upon changes in stock, the shares of Common Stock that may be sold pursuant to
Purchase Rights granted under the Plan shall not exceed in the aggregate one
million five hundred thousand (1,500,000) shares of Common Stock, plus an annual
increase to be added on the first day of each calendar year, commencing on
January 1, 2002 and ending on (and including) January 1, 2011, equal to the
lesser of (i) two percent (2%) of the shares of Common Stock outstanding on each
January 1 (rounded down to the nearest whole share and calculated on a fully
diluted basis, that is assuming the exercise of all outstanding stock options
and warrants to purchase shares of Common Stock) or (ii) four hundred forty
thousand (440,000) shares of Common Stock; provided, however, that the Board may
determine a lesser number of shares of Common Stock than each of (i) and (ii).
Notwithstanding the foregoing, any such automatic share reserve increases in the
aggregate shall not exceed one million (1,000,000) shares of Common Stock. If
any Purchase Right granted under the Plan shall for any reason terminate without
having been exercised, the shares not purchased under such Purchase Right shall
again become available for issuance under the Plan.

         (b) The shares of Common Stock subject to the Plan may be unissued
shares or shares that have been bought on the open market at prevailing market
prices or otherwise.


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5.       GRANT OF PURCHASE RIGHTS; OFFERING.

         (a) The Board may from time to time grant or provide for the grant of
Purchase Rights to purchase shares of Common Stock under the Plan to Eligible
Employees in an Offering (consisting of one or more Purchase Periods) on an
Offering Date or Offering Dates selected by the Board. Each Offering shall be in
such form and shall contain such terms and conditions as the Board shall deem
appropriate, which shall comply with the requirement of Section 423(b)(5) of the
Code that all Employees granted Purchase Rights to purchase shares of Common
Stock under the Plan shall have the same rights and privileges. The terms and
conditions of an Offering shall be incorporated by reference into the Plan and
treated as part of the Plan. The provisions of separate Offerings need not be
identical, but each Offering shall include (through incorporation of the
provisions of this Plan by reference in the document comprising the Offering or
otherwise) the period during which the Offering shall be effective, which period
shall not exceed twenty-seven (27) months beginning with the Offering Date, and
the substance of the provisions contained in Sections 6 through 9, inclusive.

         (b) If a Participant has more than one Purchase Right outstanding under
the Plan, unless he or she otherwise indicates in agreements or notices
delivered hereunder: (i) each agreement or notice delivered by that Participant
shall be deemed to apply to all of his or her Purchase Rights under the Plan,
and (ii) a Purchase Right with a lower exercise price (or an earlier-granted
Purchase Right, if different Purchase Rights have identical exercise prices)
shall be exercised to the fullest possible extent before a Purchase Right with a
higher exercise price (or a later-granted Purchase Right, if different Purchase
Rights have identical exercise prices) shall be exercised.

6.       ELIGIBILITY.

         (a) Purchase Rights may be granted only to Employees of the Company or,
as the Board may designate as provided in Section 3(b), to Employees of a
Related Corporation. Except as provided in Section 6(b), an Employee shall not
be eligible to be granted Purchase Rights under the Plan unless, on the Offering
Date, such Employee has been in the employ of the Company or the Related
Corporation, as the case may be, for such continuous period preceding such
Offering Date as the Board may require, but in no event shall the required
period of continuous employment be greater than two (2) years. In addition, the
Board may provide that no Employee shall be eligible to be granted Purchase
Rights under the Plan unless, on the Offering Date, such Employee's customary
employment with the Company or the Related Corporation is more than twenty (20)
hours per week and more than five (5) months per calendar year.

         (b) The Board may provide that each person who, during the course of an
Offering, first becomes an Eligible Employee shall, on a date or dates specified
in the Offering which coincides with the day on which such person becomes an
Eligible Employee or which occurs thereafter, receive a Purchase Right under
that Offering, which Purchase Right shall thereafter be deemed to be a part of
that Offering. Such Purchase Right shall have the same characteristics as any
Purchase Rights originally granted under that Offering, as described herein,
except that:


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                  (i) the date on which such Purchase Right is granted shall be
the "Offering Date" of such Purchase Right for all purposes, including
determination of the exercise price of such Purchase Right;

                  (ii) the period of the Offering with respect to such Purchase
Right shall begin on its Offering Date and end coincident with the end of such
Offering; and

                  (iii) the Board may provide that if such person first becomes
an Eligible Employee within a specified period of time before the end of the
Offering, he or she shall not receive any Purchase Right under that Offering.

         (c) No Employee shall be eligible for the grant of any Purchase Rights
under the Plan if, immediately after any such Purchase Rights are granted, such
Employee owns stock possessing five percent (5%) or more of the total combined
voting power or value of all classes of stock of the Company or of any Related
Corporation. For purposes of this Section 6(c), the rules of Section 424(d) of
the Code shall apply in determining the stock ownership of any Employee, and
stock which such Employee may purchase under all outstanding Purchase Rights and
options shall be treated as stock owned by such Employee.

         (d) As specified by Section 423(b)(8) of the Code, an Eligible Employee
may be granted Purchase Rights under the Plan only if such Purchase Rights,
together with any other rights granted under all Employee Stock Purchase Plans
of the Company and any Related Corporations, do not permit such Eligible
Employee's rights to purchase stock of the Company or any Related Corporation to
accrue at a rate which exceeds twenty five thousand dollars ($25,000) of Fair
Market Value of such stock (determined at the time such rights are granted, and
which, with respect to the Plan, shall be determined as of their respective
Offering Dates) for each calendar year in which such rights are outstanding at
any time.

         (e) Officers of the Company and any designated Related Corporation, if
they are otherwise Eligible Employees, shall be eligible to participate in
Offerings under the Plan. Notwithstanding the foregoing, the Board may provide
in an Offering that Employees who are highly compensated Employees within the
meaning of Section 423(b)(4)(D) of the Code shall not be eligible to
participate.

7.       PURCHASE RIGHTS; PURCHASE PRICE.

         (a) On each Offering Date, each Eligible Employee, pursuant to an
Offering made under the Plan, shall be granted a Purchase Right to purchase up
to that number of shares of Common Stock purchasable either with a percentage or
with a maximum dollar amount, as designated by the Board, but in either case not
exceeding ten percent (10%), of such Employee's Earnings (as defined by the
Board in each Offering) during the period that begins on the Offering Date (or
such later date as the Board determines for a particular Offering) and ends on
the date stated in the Offering, which date shall be no later than the end of
the Offering.


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         (b) The Board shall establish one (1) or more Purchase Dates during an
Offering as of which Purchase Rights granted under the Plan and pursuant to that
Offering shall be exercised and purchases of shares of Common Stock shall be
carried out in accordance with such Offering.

         (c) In connection with each Offering made under the Plan, the Board may
specify a maximum number of shares of Common Stock that may be purchased by any
Participant on any Purchase Date during such Offering. In connection with each
Offering made under the Plan, the Board may specify a maximum aggregate number
of shares of Common Stock that may be purchased by all Participants pursuant to
such Offering. In addition, in connection with each Offering that contains more
than one Purchase Date, the Board may specify a maximum aggregate number of
shares of Common Stock that may be purchased by all Participants on any given
Purchase Date under the Offering. If the aggregate purchase of shares of Common
Stock issuable upon exercise of Purchase Rights granted under the Offering would
exceed any such maximum aggregate number, then, in the absence of any Board
action otherwise, a pro rata allocation of the shares of Common Stock available
shall be made in as nearly a uniform manner as shall be practicable and
equitable.

         (d) The purchase price of shares of Common Stock acquired pursuant to
Purchase Rights granted under the Plan shall be not less than the lesser of:

                  (i) an amount equal to eighty-five percent (85%) of the Fair
Market Value of the shares of Common Stock on the Offering Date; or

                  (ii) an amount equal to eighty-five percent (85%) of the Fair
Market Value of the shares of Common Stock on the applicable Purchase Date.

8.       PARTICIPATION; WITHDRAWAL; TERMINATION.

         (a) An Eligible Employee may become a Participant in the Plan pursuant
to an Offering by delivering a participation agreement to the Company within the
time specified in the Offering, in such form as the Company may provide. Each
such agreement shall authorize payroll deductions of up to the maximum
percentage specified by the Board of such Participant's Earnings (as defined in
each Offering) during the Offering. The payroll deductions made for each
Participant shall be credited to a bookkeeping account for such Participant
under the Plan and shall be deposited with the general funds of the Company. To
the extent provided in the Offering, a Participant may reduce (including to
zero) or increase such payroll deductions. To the extent provided in the
Offering, a Participant may begin such payroll deductions after the beginning of
the Offering. A Participant may make additional payments into his or her account
only if specifically provided for in the Offering and only if the Participant
has not already had the maximum permitted amount withheld during the Offering.

         (b) At any time during an Offering, a Participant may terminate his or
her payroll deductions under the Plan and withdraw from the Offering by
delivering to the Company a notice of withdrawal in such form as the Company may
provide. Such withdrawal may be elected at any time prior to the end of the
Offering, except as provided in the Offering. Upon such withdrawal from the
Offering by a Participant, the Company shall distribute to such


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Participant all of his or her accumulated payroll deductions (reduced to the
extent, if any, such deductions have been used to acquire shares of Common Stock
for the Participant) under the Offering, without interest (unless otherwise
specified in the Offering), and such Participant's interest in that Offering
shall be automatically terminated. A Participant's withdrawal from an Offering
shall have no effect upon such Participant's eligibility to participate in any
other Offerings under the Plan, but such Participant shall be required to
deliver a new participation agreement in order to participate in subsequent
Offerings under the Plan.

         (c) Purchase Rights granted pursuant to any Offering under the Plan
shall terminate immediately upon a Participant ceasing to be an Employee for any
reason or for no reason (subject to any post-employment participation period
required by law) or other lack of eligibility. The Company shall distribute to
such terminated or otherwise ineligible Employee all of his or her accumulated
payroll deductions (reduced to the extent, if any, such deductions have been
used to acquire shares of Common Stock for the terminated or otherwise
ineligible Employee) under the Offering, without interest (unless otherwise
specified in the Offering).

         (d) Purchase Rights granted under the Plan shall not be transferable by
a Participant otherwise than by will or the laws of descent and distribution, or
by a beneficiary designation as provided in Section 13 and, during a
Participant's lifetime, shall be exercisable only by such Participant.

9.       EXERCISE.

         (a) On each Purchase Date during an Offering, each Participant's
accumulated payroll deductions and other additional payments specifically
provided for in the Offering (without any increase for interest) shall be
applied to the purchase of shares of Common Stock up to the maximum number of
shares of Common Stock permitted pursuant to the terms of the Plan and the
applicable Offering, at the purchase price specified in the Offering. No
fractional shares shall be issued upon the exercise of Purchase Rights granted
under the Plan unless specifically provided for in the Offering.

         (b) If any amount of accumulated payroll deductions remains in a
Participant's account after the purchase of shares of Common Stock and such
remaining amount is less than the amount required to purchase one share of
Common Stock on the final Purchase Date of an Offering, then such remaining
amount shall be held in each such Participant's account for the purchase of
shares of Common Stock under the next Offering under the Plan, unless such
Participant withdraws from such next Offering, as provided in Section 8(b), or
is not eligible to participate in such Offering, as provided in Section 6, in
which case such amount shall be distributed to the Participant after said final
Purchase Date, without interest (unless otherwise specified in the Offering). If
any amount, of accumulated payroll deductions remains in a Participant's account
after the purchase of shares of Common Stock and such remaining amount is equal
to the amount required to purchase one (1) or more whole shares of Common Stock
on the final Purchase Date of the Offering, then such remaining amount shall be
distributed in full to the Participant at the end of the Offering without
interest (unless otherwise specified in the Offering).


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         (c) No Purchase Rights granted under the Plan may be exercised to any
extent unless the shares of Common Stock to be issued upon such exercise under
the Plan are covered by an effective registration statement pursuant to the
Securities Act and the Plan is in material compliance with all applicable
federal, state, foreign and other securities and other laws applicable to the
Plan. If on a Purchase Date during any Offering hereunder the shares of Common
Stock are not so registered or the Plan is not in such compliance, no Purchase
Rights granted under the Plan or any Offering shall be exercised on such
Purchase Date, and the Purchase Date shall be delayed until the shares of Common
Stock are subject to such an effective registration statement and the Plan is in
such compliance, except that the Purchase Date shall not be delayed more than
twelve (12) months and the Purchase Date shall in no event be more than
twenty-seven (27) months from the Offering Date. If, on the Purchase Date under
any Offering hereunder, as delayed to the maximum extent permissible, the shares
of Common Stock are not registered and the Plan is not in such compliance, no
Purchase Rights granted under the Plan or any Offering shall be exercised and
all payroll deductions accumulated during the Offering (reduced to the extent,
if any, such deductions have been used to acquire shares of Common Stock) shall
be distributed to the Participants, without interest (unless otherwise specified
in the Offering).

10.      COVENANTS OF THE COMPANY.

         (a) During the terms of the Purchase Rights granted under the Plan, the
Company shall ensure that the amount of shares of Common Stock required to
satisfy such Purchase Rights are available.

         (b) The Company shall seek to obtain from each federal, state, foreign
or other regulatory commission or agency having jurisdiction over the Plan such
authority as may be required to issue and sell shares of Common Stock upon
exercise of the Purchase Rights granted under the Plan. If, after reasonable
efforts, the Company is unable to obtain from any such regulatory commission or
agency the authority that counsel for the Company deems necessary for the lawful
issuance and sale of shares of Common Stock under the Plan, the Company shall be
relieved from any liability for failure to issue and sell shares of Common Stock
upon exercise of such Purchase Rights unless and until such authority is
obtained.

11.      USE OF PROCEEDS FROM SHARES OF COMMON STOCK.

         Proceeds from the sale of shares of Common Stock pursuant to Purchase
Rights granted under the Plan shall constitute general funds of the Company.

12.      RIGHTS AS A STOCKHOLDER.

         A Participant shall not be deemed to be the holder of, or to have any
of the rights of a holder with respect to, shares of Common Stock subject to
Purchase Rights granted under the Plan unless and until the Participant's shares
of Common Stock acquired upon exercise of Purchase Rights granted under the Plan
are recorded in the books of the Company (or its transfer agent).


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13.      DESIGNATION OF BENEFICIARY.

         (a) A Participant may file a written designation of a beneficiary who
is to receive any shares of Common Stock and/or cash, if any, from the
Participant's account under the Plan in the event of such Participant's death
subsequent to the end of an Offering but prior to delivery to the Participant of
such shares of Common Stock or cash. In addition, a Participant may file a
written designation of a beneficiary who is to receive any cash from the
Participant's account under the Plan in the event of such Participant's death
during an Offering.

         (b) The Participant may change such designation of beneficiary at any
time by written notice. In the event of the death of a Participant and in the
absence of a beneficiary validly designated under the Plan who is living at the
time of such Participant's death, the Company shall deliver such shares of
Common Stock and/or cash to the executor or administrator of the estate of the
Participant, or if no such executor or administrator has been appointed (to the
knowledge of the Company), the Company, in its sole discretion, may deliver such
shares of Common Stock and/or cash to the spouse or to any one or more
dependents or relatives of the Participant, or if no spouse, dependent or
relative is known to the Company, then to such other person as the Company may
designate.

14.      ADJUSTMENTS UPON CHANGES IN SECURITIES; CORPORATE TRANSACTIONS.

         (a) If any change is made in the shares of Common Stock, subject to the
Plan, or subject to any Purchase Right, without the receipt of consideration by
the Company (through merger, consolidation, reorganization, recapitalization,
reincorporation, stock dividend, dividend in property other than cash, stock
split, liquidating dividend, combination of shares, exchange of shares, change
in corporate structure or other transaction not involving the receipt of
consideration by the Company), the Plan shall be appropriately adjusted in the
type(s), class(es) and maximum number of shares of Common Stock subject to the
Plan pursuant to Section 4(a), and the outstanding Purchase Rights granted under
the Plan shall be appropriately adjusted in the type(s), class(es), number of
shares and purchase limits of such outstanding Purchase Rights. The Board shall
make such adjustments, and its determination shall be final, binding and
conclusive. (The conversion of any convertible securities of the Company shall
not be treated as a "transaction not involving the receipt of consideration by
the Company.")

         (b) In the event of a Corporate Transaction, then: (i) any surviving or
acquiring corporation may continue or assume Purchase Rights outstanding under
the Plan or may substitute similar rights (including a right to acquire the same
consideration paid to stockholders in the Corporate Transaction) for those
outstanding under the Plan, or (ii) if any surviving or acquiring corporation
does not assume such Purchase Rights or does not substitute similar rights for
Purchase Rights outstanding under the Plan, then the Participants' accumulated
payroll deductions (exclusive of any accumulated interest that cannot be applied
toward the purchase of shares of Common Stock under the terms of the Offering)
shall be used to purchase shares of Common Stock immediately prior to the
Corporate Transaction under the ongoing Offering, and the Participants' Purchase
Rights under the ongoing Offering shall terminate immediately after such
purchase.


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15.      AMENDMENT OF THE PLAN.

         (a) The Board at any time, and from time to time, may amend the Plan.
However, except as provided in Section 14 relating to adjustments upon changes
in securities and except as to amendments solely to benefit the administration
of the Plan, to take account of a change in legislation or to obtain or maintain
favorable tax, exchange control or regulatory treatment for Participants or the
Company or any Related Corporation, no amendment shall be effective unless
approved by the stockholders of the Company to the extent stockholder approval
is necessary for the Plan to satisfy the requirements of Section 423 of the Code
or other applicable laws or regulations.

         (b) It is expressly contemplated that the Board may amend the Plan in
any respect the Board deems necessary or advisable to provide Employees with the
maximum benefits provided or to be provided under the provisions of the Code and
the regulations promulgated thereunder relating to Employee Stock Purchase Plans
and/or to bring the Plan and/or Purchase Rights granted under the Plan into
compliance therewith.

         (c) The rights and obligations under any Purchase Rights granted before
amendment of the Plan shall not be impaired by any amendment of the Plan except
(i) with the consent of the person to whom such Purchase Rights were granted,
(ii) as necessary to comply with any laws or governmental regulations, or (iii)
as necessary to ensure that the Plan and/or Purchase Rights granted under the
Plan comply with the requirements of Section 423 of the Code.

16.      TERMINATION OR SUSPENSION OF THE PLAN.

         (a) The Board in its discretion may suspend or terminate the Plan at
any time. Unless sooner terminated, the Plan shall terminate on February 27,
2011. No Purchase Rights may be granted under the Plan while the Plan is
suspended or after it is terminated.

         (b) Any benefits, privileges, entitlements and obligations under any
Purchase Rights granted under the Plan while the Plan is in effect shall not be
impaired by suspension or termination of the Plan except (i) as expressly
provided in the Plan or with the consent of the person to whom such Purchase
Rights were granted, (ii) as necessary to comply with any laws, regulations, or
listing requirements, or (iii) as necessary to ensure that the Plan and/or
Purchase Rights granted under the Plan comply with the requirements of Section
423 of the Code.

17.      EFFECTIVE DATE OF PLAN.

         The Plan shall become effective as determined by the Board, but no
Purchase Rights granted under the Plan shall be exercised unless and until the
Plan has been approved by the stockholders of the Company within twelve (12)
months before or after the date the Plan is adopted by the Board.


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18.      MISCELLANEOUS PROVISIONS.

         (a) The Plan and Offering do not constitute an employment contract.
Nothing in the Plan or in the Offering shall in any way alter the at will nature
of a Participant's employment or be deemed to create in any way whatsoever any
obligation on the part of any Participant to continue in the employ of the
Company or a Related Corporation, or on the part of the Company or a Related
Corporation to continue the employment of a Participant.

         (b) The provisions of the Plan shall be governed by the laws of the
State of Colorado without resort to that state's conflicts of laws rules.


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                            ALLOS THERAPEUTICS, INC.

                        2001 EMPLOYEE STOCK PURCHASE PLAN
                                    OFFERING

               ADOPTED BY THE BOARD OF DIRECTORS FEBRUARY 28, 2001

         In this document, capitalized terms not otherwise defined shall have
the same definitions of such terms as in the Allos Therapeutics, Inc. 2001
Employee Stock Purchase Plan.

1. GRANT; OFFERING DATE.

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

         (b) The Offering hereunder shall begin on July 1, 2001 and end on June
30, 2003. The Offering shall consist of four (4) Purchase Periods, with the
first Purchase Period ending on December 31, 2001, the second Purchase Period
ending on June 30, 2002, the third Purchase Period ending on December 31, 2002,
and the fourth Purchase Period ending on June 30, 2003. Thereafter an Offering
shall begin on each July 1 and each Offering shall be approximately two (2)
years in duration, consisting of four (4) Purchase Period(s) each of which shall
be six (6) months in length. Each Offering shall end on the day prior to the
first day of the subsequent Offering except as provided below. Except as
provided below, a Purchase Date is the last day of a Purchase Period or of an
Offering, as the case may be.

         (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) 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 the shares of Common Stock is less than it was on the Offering Date for that
Offering, that day shall become the next Offering Date, and the Offering that
would otherwise have continued in effect shall immediately terminate and the
Employees who were employed in the terminated Offering shall automatically be
enrolled in the new Offering that starts such day.

2. ELIGIBLE EMPLOYEES.

         (a) All Employees of the Company shall be granted Purchase Rights to
purchase shares of Common Stock under each Offering on the Offering Date of such
Offering, provided


                                       1.
<PAGE>   14

that each such Employee otherwise meets the employment requirements of Section
6(a) of the Plan.

         (b) Notwithstanding the foregoing, the following Employees shall not be
Eligible Employees or be granted Purchase Rights under an Offering: (i) five
percent (5%) stockholders (including ownership through unexercised and/or
unvested stock options) as described in Section 6(c) of the Plan and (ii)
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 any Offering shall, on the day after the first Purchase
Date during that Offering as of which such person first becomes an Eligible
Employee, receive 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, 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 contain herein and in the Plan, on each
Offering Date each Eligible Employee shall be granted a Purchase Right to
purchase the number of shares of Common Stock purchasable with up to ten percent
(10%) of such Eligible Employee's Earnings paid during the period of such
Offering beginning after such Eligible Employee first commences participation;
provided, however, that no Eligible Employee may have more than ten percent
(10%) of such Eligible Employee's Earnings applied to purchase shares of Common
Stock under all ongoing Offerings under the Plan and all other plans of the
Company intended to qualify as Employee Stock Purchase Plans under Section 423
of the Code.

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

         (c) Notwithstanding the foregoing, the maximum number of shares of
Common Stock that an Eligible Employee may purchase on any Purchase Date in an
Offering shall be such


                                       2.
<PAGE>   15

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 plans intended to qualify as Employee Stock Purchase Plans
under Section 423 of the Code, 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 Employee Stock Purchase Plan.

         (d) The maximum aggregate number of shares of Common Stock available to
be purchased by all Eligible Employees 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 an Eligible Employee may purchase in any 12-month period
during any Offering shall not exceed two thousand five hundred (2,500) shares.

         (f) Notwithstanding the foregoing, the maximum number of shares of
Common Stock that an Eligible Employee may purchase during any Offering shall
not exceed five thousand (5,000) shares.

4. PURCHASE PRICE.

         The purchase price of shares of Common Stock under the Offering shall
be the lesser of: (i) eighty-five percent (85%) of the Fair Market Value of such
shares of Common Stock on the Offering Date or (ii) or 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) An Eligible Employee may elect to participate in an Offering on the
Offering Date or as of the first day following any Purchase Date; provided,
however, that a person who first becomes an Eligible Employee during an Offering
may elect to participate at the Offering Date applicable to such Eligible
Employee in accordance with Section 2(c) of this Offering document. An Eligible
Employee shall become a Participant in an Offering by delivering an enrollment
form authorizing payroll deductions. Such deductions must be in whole
percentages of Earnings, with a minimum percentage of one percent (1%) and a
maximum percentage of ten percent (10%). A Participant may not make additional
payments into his or her account. A


                                       3.
<PAGE>   16

Participant shall complete such enrollment form as the Company provides, and the
completed enrollment form must be delivered to the Company prior to the date
participation is to be effective, unless a later time for filing the enrollment
form is set by the Company for all Eligible Employees with respect to a given
Offering.

         (b) A Participant may reduce his or her participation level once during
the six (6) month period ending on a Purchase Date, excluding only each ten (10)
day period immediately preceding a Purchase Date (or such shorter period of time
as determined by the Company and communicated to Participants). In addition, a
Participant may reduce his or her participation level to zero percent (0%) at
any time during the course of an Offering, excluding only each ten (10) day
period immediately preceding a Purchase Date (or such shorter period of time as
determined by the Company and communicated to Participants). Any such change in
participation shall be made by delivering a notice to the Company or a
designated Related Corporation in such form and at such time as the Company
provides.

         (c) A Participant may withdraw from an Offering and receive his or her
accumulated payroll deductions from the Offering (reduced to the extent, if any,
such deductions 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 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.

6. PURCHASES.

         Subject to the limitations contained herein, on each Purchase Date,
each Participant's accumulated payroll deductions (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.


                                       4.
<PAGE>   17

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 a tax-qualified 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.


                                       5.