Exhibit 3.04

BYLAWS        OF        ALLOS THERAPEUTICS, INC.        (A DELAWARE CORPORATION)

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BYLAWS

OF

ALLOS THERAPEUTICS, INC.

(A DELAWARE CORPORATION)

ARTICLE I
OFFICES

Section 1.Registered Office. The registered office of the corporation in the State of Delaware shall be in
the City of Wilmington, County of New Castle.

Section 2.Other Offices. The corporation shall also have and maintain an office or principal place of business at such place as
may be fixed by the Board of Directors, and may also have offices at such other places, both within and without the State of Delaware as the Board of Directors may from time to time determine or the
business of the corporation may require.

ARTICLE II
CORPORATE SEAL

Section 3.Corporate Seal. The corporate seal shall consist of a die bearing the name of the corporation
and the inscription, "Corporate Seal-Delaware." Said seal may be used by causing it or a facsimile thereof to be impressed or affixed or reproduced or otherwise.

ARTICLE III
STOCKHOLDERS' MEETINGS

Section 4.Place of Meetings. Meetings of the stockholders of the corporation shall be held at such place,
either within or without the State of Delaware, as may be designated from time to time by the Board of Directors, or, if not so designated, then at the office of the corporation required to be
maintained pursuant to Section 2 hereof.

Section 5.Annual Meeting.



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Section 6.Special Meetings.



Section 7. Notice of Meetings. Except as otherwise provided by law or the Certificate of Incorporation, written notice of each
meeting of stockholders shall be given not less than ten (10) nor more than sixty (60) days before the date of the meeting to each stockholder entitled to vote at such meeting, such
notice to specify the place, date and hour and purpose or purposes of the meeting. Notice of the time, place and purpose of any meeting of stockholders may be waived in writing, signed by the person
entitled to notice thereof, either before or after such meeting, and will be waived by any stockholder by his attendance thereat in person or by proxy, except when the stockholder attends a meeting
for the express purpose of objecting, at the beginning of the meeting, to the transaction of any business because the meeting is not lawfully called or convened. Any stockholder so waiving notice of
such meeting shall be bound by the proceedings of any such meeting in all respects as if due notice thereof had been given.

Section 8.Quorum. At all meetings of stockholders, except where otherwise provided by statute or by the Certificate of
Incorporation, or by these Bylaws, the presence, in person or by proxy duly authorized, of the holders of a majority of' the outstanding shares of stock entitled to vote shall constitute a quorum for
the transaction of business. In the absence of a quorum, any meeting of stockholders may be adjourned, from time to time, either by the chairman of the meeting or by vote of the holders of a majority
of the shares represented thereat, but no other business shall be transacted at such meeting. The stockholders present at a duly called or convened meeting, at which a quorum is present, may continue
to transact business until adjournment, notwithstanding "the withdrawal of enough stockholders to leave less than a quorum. Except as otherwise provided by law, the Certificate of Incorporation or
these Bylaws, all action taken by the holders of a majority of the vote cast, excluding abstentions, at any meeting at which a quorum is present shall be valid and binding upon the corporation;
provided, however, that directors shall be elected by a plurality of the votes of the shares

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present
in person or represented by proxy at the meeting and entitled to vote on the election of directors. Where a separate vote by a class or classes or series is required, except where otherwise
provided by the statute or by the Certificate of Incorporation or these Bylaws, a majority of the outstanding shares of such class or classes or series, present in person or represented by proxy,
shall constitute a quorum entitled to take action with respect to that vote on that matter and, except where otherwise provided by the statute or by the Certificate of Incorporation or these Bylaws,
the affirmative vote of the majority (plurality, in the case of the election of directors) of the votes cast, including abstentions, by the holders of shares of such class or classes or series shall
be the act of such class or classes or series.

Section 9. Adjournment and Notice of Adjourned Meetings. Any meeting of stockholders, whether annual or special, may be adjourned
from time., to time either by the chairman of the meeting or by the vote of a majority of the shares casting votes, excluding abstentions. When a meeting is adjourned to another time or place, notice
need not be given of the adjourned meeting if the time and place thereof are announced at the meeting at which the adjournment is taken. At the adjourned meeting, the corporation may transact any
business which might have been transacted at the original meeting. If the adjournment is for more than thirty (30) days or if after the adjournment a new record (late is fixed for the adjourned
meeting, a notice of the adjourned meeting shall be given to each stockholder of record entitled to vote at the meeting.

Section 10.Voting Rights. For the purpose of determining those stockholders entitled to vote at any meeting of the stockholders,
except as otherwise provided by law, only persons in whose names shares stand on the stock records of the corporation on the record date, as provided in Section 12 of these Bylaws, shall be
entitled to vote at any meeting of stockholders. Every person entitled to vote or execute consents shall have the right to do so either in person or by an agent or agents authorized by a proxy granted
in accordance with Delaware law. An agent so appointed need not be a stockholder. No proxy shall be voted after three (3) years from its date of creation unless the proxy provides for a longer
period.

Section 11.Joint Owners of Stock. If shares or other securities having voting power stand of record in the names of two
(2) or more persons, whether fiduciaries, members of a partnership, joint tenants, tenants in common, tenants by the entirety, or otherwise, or if two (2) or more persons have the same
fiduciary relationship respecting the same shares, unless the Secretary is given written notice to the contrary and is furnished with a copy of the instrument or order appointing them or creating the
relationship wherein it is so provided, their acts with respect to voting shall have the following effect: (a) if only one (1) votes, his act binds all; (b) if more than one
(1) votes, the act of the majority so voting binds all; (c) if more than one (1) votes, but the vote is evenly split on any particular matter, each faction may vote the securities
in question proportionally, or may apply to the Delaware Court of Chancery for relief as provided in the General Corporation Law of Delaware, Section 217(b). If the instrument filed with the
Secretary shows that any such tenancy is held in unequal interests, a majority or even-split for the purpose of subsection (c) shall be a majority or even-split
in interest.

Section 12. List of Stockholders. The Secretary shall prepare and make, at least ten (10) days before every meeting of
stockholders, a complete list of the stockholders entitled to vote at said meeting, arranged in alphabetical order, showing the address of each stockholder and the number of shares registered in the
name of each stockholder. Such list shall be open to the examination of any stockholder, for any purpose germane to the meeting, during ordinary business hours, for a period of at least ten
(10) days prior to the meeting, either at a place within the city where the meeting is to be held, which place shall be specified in the notice of the meeting, or, if not specified, at the
place where the meeting is to be held. The list shall be produced and kept at the time and place of meeting during the whole time thereof and may be inspected by any stockholder who is present.

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Section 13.Action Without Meeting.



Section 14. Organization.



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ARTICLE IV
DIRECTORS

Section 15.Number and Term of Office. The Board of Directors shall consist of one or more members. The
authorized number of directors of the corporation shall be fixed from time to time by resolution of the Board of Directors. Directors need not be stockholders. If for any cause, the directors shall
not have been elected at an annual meeting, they may be elected as soon thereafter as convenient at a special meeting of the stockholders called for that purpose in the manner provided in these
Bylaws.

Section 16. Powers. The powers of the corporation shall be exercised, its business conducted and its property controlled by the
Board of Directors, except as may be otherwise provided by statute or by the Certificate of Incorporation.

Section 17.Vacancies. Unless otherwise provided in the Certificate of Incorporation, any vacancies on the Board of Directors
resulting from death, resignation, disqualification, removal or other causes and any newly created directorships resulting from any increase in the number of directors, shall unless the Board of
Directors determines by resolution that any such vacancies or newly created directorships shall be filled by stockholders, be filled only by the affirmative vote of a majority of the directors then in
office, even though less than a quorum of the Board of Directors. Any director elected in accordance with the preceding sentence shall hold office for the remainder of the full term of the director
for which the vacancy was created or occurred and until such director's successor shall have been elected and qualified. A vacancy in the Board of Directors shall be deemed to exist under this Bylaw
in the case of the death, removal or resignation of any director.

Section 18.Resignation. Any director may resign at any time by delivering his written resignation to the Secretary, such
resignation to specify whether it will be effective at a particular time, upon receipt by the Secretary or at the pleasure of the Board of Directors. If no such specification is made, it shall be
deemed effective at the pleasure of the Board of Directors. When one or more directors shall resign from the Board of Directors, effective at a future date, a majority of the directors then in office,
including those who have so resigned, shall have power to fill such vacancy or vacancies, the vote thereon to take effect when such resignation or resignations shall become effective, and each
Director so chosen shall hold office for the unexpired portion of the term of the Director whose place shall be vacated and until his successor shall have been duly elected and qualified.

Section 19. Removal. Subject to the rights of the holders of any series of Preferred Stock, no director shall be removed without
cause. Subject to any limitations imposed by law, the Board of Directors or any individual director may be removed from office at any time with cause by the affirmative vote of the holders of a
majority of the voting power of all the then-outstanding shares of voting stock of the corporation, entitled to vote at an election of directors (the "Voting Stock").

Section 20.Meetings.



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Section 21. Quorum and Voting.



Section 22.Action Without Meeting. Unless otherwise restricted by the Certificate of Incorporation or these Bylaws, any action
required or permitted to be taken at any meeting of the Board of Directors or of any committee thereof may be taken without a meeting, if all members of the Board of Directors or committee, as the
case may be, consent thereto in writing, and such writing or writings are filed with the minutes of proceedings of the Board of Directors or committee.

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Section 23.Fees and Compensation. Directors shall be entitled to such compensation for their services as may be approved by the
Board of Directors, including, if so approved, by resolution of the Board of Directors, a fixed sum and expenses of attendance, if any, for attendance at each regular or special meeting of the Board
of Directors and at any meeting of a committee of the Board of Directors. Nothing herein contained shall be construed to preclude any director from serving the corporation in any other capacity as an
officer, agent, employee, or otherwise and receiving compensation therefor.

Section 24.Committees.



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Section 25.Organization. At every meeting of the directors, the Chairman of the Board of Directors, or, if a Chairman has not been
appointed or is absent, the President, or if the President is absent, the most senior Vice President, or, in the absence of any such officer, a chairman of the meeting chosen by a majority of the
directors present, shall preside over the meeting. The Secretary, or in his absence, an Assistant Secretary directed to do so by the President, shall act as secretary of the meeting.

ARTICLE V
OFFICERS

Section 26.Officers Designated. The officers of the corporation shall include, if and when designated by
the Board of Directors, the Chairman of the Board of Directors, the Chief Executive Officer, the President, one or more Vice Presidents, the Secretary, the Chief Financial Officer, the Treasurer, the
Controller, all of whom shall be elected at the annual organizational meeting of the Board of Directors. The Board of Directors may also appoint one or more Assistant Secretaries, Assistant
Treasurers, Assistant Controllers and such other officers and agents with such powers and duties as it shall deem necessary. The Board of Directors may assign such additional titles to one or more of
the officers as it shall deem appropriate. Any one person may hold any number of offices of the corporation at any one time unless specifically prohibited therefrom by law. The salaries and other
compensation of the officers of the corporation shall be fixed by or in the manner designated by the Board of Directors.

Section 27.Tenure and Duties of Officers.



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Section 28. Delegation of Authority. The Board of Directors may from time to time delegate the powers or duties of any officer to
any other officer or agent, notwithstanding any provision hereof.

Section 29.Resignations. Any officer may resign at any time by giving written notice to the Board of Directors or to the President
or to the Secretary. Any such resignation shall be effective when received by the person or persons to whom such notice is given, unless a later time is specified therein, in which event the
resignation shall become effective at such later time. Unless otherwise specified in such notice, the acceptance of any such resignation shall not be necessary to make it effective. Any resignation
shall be without prejudice to the rights, if any, of the corporation under any contract with the resigning officer.

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Section 30.Removal. Any officer may be removed from office at any time, either with or without cause, by the affirmative vote of a
majority of the directors in office at the time, or by the unanimous written consent of the directors in office at the time, or by any committee or superior officers upon whom such power of removal
may have been conferred by the Board of Directors.

ARTICLE VI
EXECUTION OF CORPORATE INSTRUMENTS AND VOTING OF SECURITIES OWNED BY THE CORPORATION

Section 31.Execution of Corporate Instruments. The Board of Directors may, in its discretion, determine
the method and designate the signatory officer or officers, or other person or persons, to execute on behalf of the corporation any corporate instrument or document, or to sign on behalf of the
corporation the corporate name without limitation, or to enter into contracts on behalf of the corporation, except where otherwise provided by law or these Bylaws, and such execution or signature
shall be binding upon the corporation.

Unless
otherwise specifically determined by the Board of Directors or otherwise required by law, promissory notes, deeds of trust, mortgages and other evidences of indebtedness of the
corporation, and other corporate instruments or documents requiring the corporate seal, and certificates of shares of stock owned by the corporation, shall be executed, signed or endorsed by the
Chairman of the Board of Directors, or the President or any Vice President, and by the Secretary or Treasurer or any Assistant Secretary or Assistant Treasurer. All other instruments and documents
requiring the corporate signature, but not requiring the corporate seal, may be executed as aforesaid or in such other manner as may be directed by the Board of Directors.

All
checks and drafts drawn on banks or other depositaries on funds to the credit of the corporation or in special accounts of the corporation shall be signed by such person or persons
as the Board of Directors shall authorize so to do.

Unless
authorized or ratified by the Board of Directors or within the agency power of an officer, no officer, agent or employee shall have any power or authority to bind the corporation
by any contract or engagement or to pledge its credit or to render it liable for any purpose or for any amount.

Section 32. Voting of Securities Owned by the Corporation. All stock and other securities of other corporations owned or held by
the corporation for itself, or for other parties in any capacity, shall be voted, and all proxies with respect thereto shall be executed, by the person authorized so to do by resolution of the Board
of Directors, or, in the absence of such authorization, by the Chairman of the Board of Directors, the Chief Executive Officer, the President, or any Vice President.

ARTICLE VII
SHARES OF STOCK

Section 33.Form and Execution of Certificates. Certificates for the shares of stock of the
corporation shall be in such form as is consistent with the Certificate of Incorporation and applicable law. Every holder of stock in the corporation shall be entitled to have a certificate signed by
or in the name of the corporation by the Chairman of the Board of Directors, or the President or any Vice President and by the Treasurer or Assistant Treasurer or the Secretary or Assistant Secretary,
certifying the number of shares owned by him in the corporation. Any or all of the signatures on the certificate may be facsimiles. In case any officer, transfer agent, or registrar who has signed or
whose facsimile signature has been placed upon a certificate shall have ceased to be such officer, transfer agent, -or registrar before such certificate is issued, it may be issued with
the same effect as if he were such officer, transfer agent, or registrar at the date of issue. Each certificate shall state upon the face or back thereof, in full or in summary, all of the powers,
designations, preferences, and rights, and the limitations or restrictions of the shares authorized to be issued or shall, except as otherwise required by

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law,
set forth on the face or back a statement that the corporation will furnish without charge to each stockholder who so requests the powers, designations, preferences and relative, participating,
optional, or other special rights of each class of stock or series thereof and the qualifications, limitations or restrictions of such preferences and/or rights. Within a reasonable time after the
issuance or transfer of uncertificated stock, the corporation shall send to the registered owner thereof a written notice containing the information required to be set forth or stated on certificates
pursuant to this section or otherwise required by law or with respect to this section a statement that the corporation will furnish without charge to each stockholder who so requests the
powers, designations, preferences and relative participating, optional or other special rights of each class of stock or series thereof and the qualifications, limitations or restrictions of such
preferences and/or rights. Except as otherwise expressly provided by law, the rights and obligations of the holders of certificates representing stock of the same class and series shall be identical.

Section 34.Lost Certificates. A new certificate or certificates shall be issued in place of any certificate or certificates
theretofore issued by the corporation alleged to have been lost, stolen, or destroyed, upon the making of an affidavit of that fact by the person claiming the certificate of stock to be lost, stolen,
or destroyed. The corporation may require, as a condition precedent to the issuance of a new certificate or certificates, the owner of such lost, stolen, or destroyed certificate or certificates, or
his legal representative, to advertise the same in such manner as it shall require or to give the corporation a surety bond in such form and amount as it may direct as indemnity against any claim that
may be made against the corporation with respect to the certificate alleged to have been lost, stolen, or destroyed.

Section 35.Transfers.



Section 36. Fixing Record Dates.



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Section 37.Registered Stockholders. The corporation shall be entitled to recognize the exclusive right of a person registered on
its books as the owner of shares to receive dividends, and to vote as such owner, and shall not be bound to recognize any equitable or other claim to or interest in such share or shares on the part of
any other person whether or not it shall have express or other notice thereof, except as otherwise provided by the laws of Delaware.

ARTICLE VIII
OTHER SECURITIES OF THE CORPORATION

Section 38.Execution of Other Securities. All bonds, debentures and other corporate securities of the
corporation, other than stock certificates (covered in Section 33), may be signed by the Chairman of the Board of Directors, the President or any Vice President, or such other person as may be
authorized by the Board of Directors, and the corporate seal impressed thereon or a facsimile of such seal imprinted thereon and attested by the signature of the Secretary or an Assistant Secretary,
or the Chief Financial Officer or Treasurer or an Assistant Treasurer; provided, however, that where any such bond, debenture or other corporate security shall be authenticated by the manual
signature, or where permissible facsimile signature, of a trustee under an indenture pursuant to which such bond, debenture or other corporate security shall be issued, the signatures of the persons
signing and attesting the corporate seal on such bond, debenture or other corporate security may be the imprinted facsimile of the signatures of such persons. Interest coupons appertaining to any such
bond, debenture or other corporate security, authenticated by a trustee as aforesaid, shall be signed by the Treasurer or an Assistant Treasurer of the corporation or such other person as may be
authorized by the Board of Directors, or bear imprinted thereon the facsimile signature of such person. In case any officer who shall have signed or attested any bond, debenture or other corporate
security, or whose facsimile signature shall appear thereon or on any such interest coupon, shall have ceased to be such officer

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before
the bond, debenture or other corporate security so signed or attested shall have been delivered, such bond, debenture or other corporate security nevertheless may be adopted by the corporation
and issued and delivered as though the person who signed the same or whose facsimile signature shall have been used thereon had not ceased to be such officer of the corporation.

ARTICLE IX
DIVIDENDS

Section 39.Declaration of Dividends. Dividends upon the capital stock of the corporation, subject to the
provisions of the Certificate of Incorporation, if any, may be declared by the Board of Directors pursuant to law at any regular or special meeting. Dividends may be paid in cash, in property, or in
shares of the capital stock, subject to the provisions of the Certificate of Incorporation.

Section 40. Dividend Reserve. Before payment of any dividend, there may be set aside out of any funds of the corporation available
for dividends such sum or sums as the Board of Directors from time to time, in their absolute discretion, think proper as a reserve or reserves to meet contingencies, or for equalizing dividends, or
for repairing or maintaining any property of the corporation, or for such other purpose as the Board of Directors shall think conducive to the interests of the corporation, and the Board of Directors
may modify or abolish any such reserve in the manner in which it was created.

ARTICLE X
FISCAL YEAR

Section 41.Fiscal Year. The fiscal year of the corporation shall be fixed by resolution of the Board of
Directors.

ARTICLE XI
INDEMNIFICATION

Section 42.Indemnification of Directors, Executive Officers, Other Officers, Employees and Other Agents.



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ARTICLE XII
NOTICES

Section 43.Notices.



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ARTICLE XIII
AMENDMENT

Section 44.Amendments. Subject to paragraph (h) of Section 43 of the Bylaws, the
Bylaws may be altered or amended or new Bylaws adopted by the affirmative vote of at least sixty-six and two-thirds percent (662/3%) of the voting power of all
of the then-outstanding shares of the Voting Stock. The Board of Directors shall also have the power to adopt, amend, or repeal Bylaws.

ARTICLE XIV
LOANS TO OFFICERS

Section 45.Loans to Officers. The corporation may lend money to, or guarantee any obligation of, or
otherwise assist any officer or other employee of the corporation or of its subsidiaries, including any officer or employee who is a Director of the corporation or its subsidiaries, whenever, in the
judgment of the Board of Directors, such loan, guarantee or assistance may reasonably be expected to benefit the corporation. The loan, guarantee or other assistance may be with or without interest
and may be unsecured, or secured in such manner as the Board of Directors shall approve, including, without limitation, a pledge of shares of stock of the corporation. Nothing in these Bylaws shall be
deemed to deny, limit or restrict the powers of guaranty or warranty of the corporation at common law or under any statute.

ARTICLE XV
MISCELLANEOUS

Section 46.Annual Report.



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