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Exhibit 10.33
ENTREMED, INC.

                     CHILDREN'S HOSPITAL RESEARCH AGREEMENT

       This Agreement ("Agreement") entered into this 24th day of June, 1999
(the "Effective Date"), by and between Children's Hospital, 300 Longwood Avenue,
Boston, Massachusetts 02115-5737 ("Hospital"), and EntreMed, Inc., 9640 Medical
Center Drive, Suite 200, Rockville, Maryland 20850 ("EntreMed")

       WHEREAS, Hospital owns certain inventions that may be useful in the
treatment of diseases in humans or animals and is interested in having a
corporate sponsor and licensee to clinically develop these inventions;

       WHEREAS, EntreMed is interested in funding and/or implementing the
clinical development of certain of the inventions in return for options for
licensing certain of the inventions;

       WHEREAS, Hospital and EntreMed entered into a Children's Hospital
Research Agreement dated September 29, 1993, as amended on August 23, 1995 (the
"1993 Agreement);

       WHEREAS, the parties now wish to amend and restate the 1993 Agreement in
its entirety as of the Effective Date by entering into three agreements dated
June 24, 1999; and

       WHEREAS, the research program contemplated by this Agreement is of mutual
interest and benefit to Hospital and to EntreMed and may further the practice of
medicine and the research agenda of the Hospital in a manner consistent with its
status as a non-profit, tax-exempt, teaching Hospital.

       NOW, THEREFORE, the parties agree as follows:

1.     Scope of Work

       (a)    Hospital agrees to use reasonable efforts to perform the Research
              and Clinical Development Program entitled "Angiogenesis Research
              Program" ("Program") in accordance with Exhibit A, attached hereto
              and made a part of this Agreement as the same may be amended by
              the parties from time to time.

       (b)    Any alteration in or amendment to the Program must be approved in
              writing by both Hospital and EntreMed prior to such alteration or
              amendment being effective.

2.     Period of Performance

       (a)    The Program shall be conducted during the period beginning on the
              Effective Date, through September 29, 2000, and will be subject to
              renewal only by written mutual agreement of EntreMed and Hospital.


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3.     Principal Investigator

       (a)    The Principal Investigator for the Program will be Dr. M. Judah
              Folkman ("Principal Investigator") of the Department of Surgery.
              In the event the Principal Investigator becomes unable to complete
              the Program for any reason, EntreMed and Hospital may mutually
              agree upon a substitute Principal Investigator, in which event
              this Agreement shall continue in full force and effect. If
              EntreMed and Hospital cannot agree on a substitute, either party
              may immediately thereafter terminate this Agreement, subject to
              the requirements of Section 11(f) of this Agreement.

4.     Research Program Support

       (a)    Primary Program Support. EntreMed agrees to pay Hospital One
              Million Four Hundred Thousand Dollars ($1,400,000) to fund the
              Program in accordance with the conditions and terms of this
              Agreement.

       (b)    Payments. On September 29, 1999, EntreMed will pay Hospital the
              sum of $700,000 and thereafter will make one additional payment of
              $700,000 on March 29, 2000, in accordance with the conditions and
              terms set forth herein.

       (c)    Payments. Payments of all sums due hereunder shall be made by
              check payable as follows:

                      Children's Hospital
                      Research Finance Office
                      300 Longwood Avenue
                      Boston, MA 02115-5737

       (d)    Late Payments. Late payments shall bear interest from the due date
              until payment at a rate of the lower of one and one-half percent
              (1 1/2%) per month, or the maximum amount permitted by law. The
              payment of such interest shall not forclose Hospital from
              exercising any other rights it may have as a consequence of the
              lateness of any payment, including without limitation termination
              under Article 11(d).

5.     Equipment

       (a)    Equipment purchased as part of the Program shall be owned by
              the Hospital, shall be physically located at the Hospital, and
              shall remain as property of the Hospital following completion of
              the Program.

6.     Publications

       (a)    EntreMed acknowledges that Hospital is an academic medical center
              and that Dr. Folkman and his collaborators shall be free to
              publish results of their studies without restraint.
              Notwithstanding this, Hospital agrees to send EntreMed copies of
              any manuscripts resulting from the Program and submitted for
              consideration for publication or any abstracts that are submitted
              to a conference no later than the same day the manuscript or
              abstract is submitted. Hospital agrees to use reasonable efforts


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       to notify EntreMed at least one month in advance of any instances where
       the results of the Program will be presented at a conference by
       invitation and without abstract. EntreMed will notify Hospital if any
       action is necessary to secure patent protection for the technology and
       Hospital agrees to take such action, subject to the terms and conditions
       hereof. If EntreMed so elects, Hospital agrees to include in any
       publication of the results of the Program acknowledgment of EntreMed's
       financial and technical support.

7.     Intellectual Property

       (a)    Any invention conceived or first reduced to practice by Hospital
              or Hospital personnel in the performance of the Program shall be
              owned by Hospital ("Invention"). Any invention conceived or first
              reduced to practice by EntreMed or EntreMed personnel at
              EntreMed's facilities during the term of this Agreement shall be
              owned by EntreMed. Any invention conceived or first reduced to
              practice jointly by Hospital or Hospital personnel and EntreMed or
              EntreMed personnel shall be jointly owned by Hospital and
              EntreMed; for jointly-owned inventions, Hospital agrees to offer
              an option to license the Hospital's interest in the invention
              according to Section 7(c).

       (b)    Hospital agrees to notify EntreMed as soon as possible when a new,
              potentially patentable Invention has been identified and disclosed
              to the Technology Transfer Office. EntreMed will immediately order
              a patentability and infringement search and, if the Invention is
              patentable, will be responsible, at EntreMed's expense, for filing
              and prosecuting patent applications on behalf of Hospital in
              Hospital's name covering the new Inventions, with appropriate and
              timely review and approval by Hospital. EntreMed shall solicit
              Hospital's comments prior to any significant actions required
              during filing and prosecution and provide Hospital with drafts of
              proposed actions and responses sufficiently in advance to allow
              time for comment and with file copies after the action is
              completed. If EntreMed decides not to file a patent application,
              EntreMed will notify Hospital within [ninety) [90] days of
              receiving disclosure of the new Invention and if EntreMed decides
              not to maintain prosecution of any patent application, EntreMed
              will notify Hospital in a timely fashion. Hospital may elect to
              file or maintain prosecution of such patent rights at its own
              expense; and Hospital shall be entitled to dispose of such patent
              rights without limitation, and EntreMed shall have no further
              option, license or other rights thereto.

       (c)    For Inventions for which EntreMed shall elect to file and maintain
              prosecution of a patent application, Hospital grants to EntreMed
              an exclusive nine-month option to decide whether or not to
              negotiate an exclusive license. Such option period shall begin at
              the date of filing of a provisional patent application or a
              non-provisional patent application. At the end of the nine-month
              option period after filing of a provisional patent application,
              EntreMed may request an additional six-month option period. In
              consideration for granting the additional six-month period,
              EntreMed will agree to file a non-provisional patent application
              at EntreMed's expense. If EntreMed chooses to license such patent
              rights during either option period, EntreMed shall have an
              additional three-month period in which to negotiate and enter into
              a license on the terms and conditions of the model license
              agreement (Exhibit B). During this three-month period, EntreMed
              will provide a development plan to Hospital which will include a
              time frame for implementation of the


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              development plan. This development plan will be updated
              semiannually. If EntreMed chooses not to license each patent
              rights, Hospital shall have the right to license to a third party;
              and EntreMed shall have no further option, license or other rights
              thereto.

       (d)    Any license granted pursuant to this Agreement shall conform to
              the terms and conditions of the License attached as Exhibit B.

       (e)    Any license granted pursuant to this Article shall be subject to a
              reservation of the unrestricted right of Hospital and inventors
              (while employed by Hospital or other non-profit institution) to
              use subject matter claimed in the licensed patent(s) or patent
              application(s) for research purposes only at no cost to Hospital
              and the right to license to non-profit institutions for research
              purposes only.

       (f)    EntreMed shall retain all invention disclosures submitted by
              Hospital in confidence and use its best efforts to prevent their
              disclosure to third parties. EntreMed shall be relieved of this
              obligation only when this information becomes publicly available
              through no fault of EntreMed.

8.     Indemnification

       (a)    EntreMed shall indemnify, defend and hold harmless Hospital and
              its board members, officers, medical staff, employees, and agents
              from and against any and all liability, damage, loss or expense
              (including reasonable attorneys' fees and expenses of litigation)
              incurred by or imposed upon it or any one of them in connection
              with any claims, suits, actions, demands or judgments arising out
              of, resulting from or related to performance under this Agreement,
              regardless of the theory of liability (including, but not limited
              to, actions in the form of tort, warranty, or strict liability),
              to the extent that such liability, loss, damage or expense is the
              result of the acts or omissions of EntreMed or any of its board
              members, officers, agents, servants, and employees.

       (b)    EntreMed agrees, at its own expense, to provide attorneys
              reasonably acceptable to the Hospital to defend against any
              actions brought or filed against any party indemnified hereunder
              with respect to the subject of indemnity contained herein, whether
              or not such actions are rightfully brought. Hospital shall
              promptly notify EntreMed if any such action shall be brought or
              flied or claim made.

       (c)    This Article 8 shall survive expiration or termination of this
              Agreement.

9.     Biological Materials Transfer

       (a)    Unique clones, chemicals, proteins or reagents developed or
              discovered under the Program by Hospital may be shared with
              scientists at non-profit academic or governmental institutions
              upon execution of Hospital's Materials Transfer Agreement for
              commercially significant materials. Requests for such materials
              that originate from commercial entities will be discussed with
              EntreMed, and Hospital will consider the potential effect of such
              transfers on the Program before deciding whether to transfer such
              materials.


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10.    Timely Pre-Clinical and Clinical Development

       (a)    As a condition to obtaining a license to the patent rights to
              Inventions under Section 7, EntreMed agrees to support clinical
              development, clinical trial and regulatory management of licensed
              products. If EntreMed decides to sublicense the licensed product
              and patent rights, in whole or for a field of use, the sublicensee
              must be acceptable to Hospital in that such sublicensee can
              provide the resources required to bring the Invention to the
              marketplace. Such acceptance of a sublicensee by Hospital will not
              be unreasonably withheld.

       (b)    EntreMed agrees to notify Hospital in a timely way of its decision
              to discontinue preclinical or clinical development of any licensed
              product and its reasons for doing so. The license(s) held by
              EntreMed to Patent Rights (as defined in the license agreement for
              such licensed product) for that Licensed Product (as defined in
              the license agreement for such licensed product) will be
              terminated upon notice from Hospital.

11.    Term and Termination

       (a)    The term of this Agreement begins on the Effective Date and
              terminates on September 29, 2000, unless sooner terminated as
              provided below.

       (b)    Performance under this Agreement may be terminated by EntreMed at
              any time with or without cause, and by Hospital without cause,
              upon one (1) year prior written notice to the other party. If
              Hospital terminates this Agreement under this Article 11(b), all
              options and rights to Inventions and patent rights granted in this
              Agreement to EntreMed shall remain in effect under Article 7 and
              all licenses granted prior to the effective date of termination
              shall remain in effect subject to the terms of the applicable
              license agreement entered into between EntreMed and Hospital.
              EntreMed shall continue to fund the Program for the shorter of
              either one year following notice of termination or the remainder
              of the term set forth in Article 11(a).

       (c)    In the event of termination by EntreMed under Article 11(b), all
              options and rights to Inventions and patent rights granted in
              Article 7 shall immediately terminate this Agreement and
              coincidentally with EntreMed's notice of termination. Any license
              agreement granted to EntreMed under Article 7 prior to such notice
              of termination, shall survive, subject to the terms of said
              license agreement.

       (d)    In the event of EntreMed's material breach of this Agreement,
              including without limitation, failure to meet its payment
              obligation under Article 4, Hospital shall have the right to give
              notice of breach, and EntreMed shall have thirty (30) days to
              cure. If EntreMed shall not cure such breach within the thirty-day
              period, Hospital shall have the right to immediately terminate
              this Agreement and all options and rights to Inventions and patent
              rights granted in Article 7 and/or all license and other rights
              granted in any license agreements executed prior to the date of
              notice of termination of Article 7 rights under this Agreement or
              the 1993 Agreement, such notice to be given in writing to
              EntreMed.


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       (e)    In the event of termination by Hospital under Article 11(b), and
              upon sending its notice of termination, Hospital agrees to
              promptly take all responsible steps to reduce the costs to
              EntreMed, and Hospital shall return at termination any unexpended
              funds to EntreMed less any non-refundable costs including
              non-cancelable obligations Hospital has incurred in the
              performance of the Program prior to the date of notice of such
              termination. In no event shall such deduction exceed the total
              support specified in Article 4.

       (f)    In the event of termination under Article 3 and upon the
              terminating party sending its notice of termination, Hospital
              agrees to promptly take all responsible steps to reduce the costs
              to EntreMed, and Hospital shall return at termination any
              unexpended funds to EntreMed less any non-refundable costs
              including, but not limited to non-cancelable obligations Hospital
              has incurred in the performance of the Program prior to the date
              of notice of such termination. In no event shall such deduction
              exceed the total support specified in Article 4. EntreMed agrees
              to fund salaries of essential personnel for a period of nine
              months from notice of termination. All options and rights to
              Inventions and patent rights granted in Article 7 to EntreMed
              shall remain in effect and all licenses granted prior to the
              effective date of termination shall remain in effect subject to
              the terms of the applicable license agreement entered into between
              EntreMed and Hospital.

       (g)    The following provisions shall survive any expiration or
              termination of this Agreement: 4(a) as to the Option, 5(a), 7(a),
              8, 11(b), 11(c), 11(f), 11(g), 12(a), 15 (except (b) and (g) and
              16.

12.    Communications

       (a)    Notice. All medical/scientific and other communications, reports,
              and notices shall be delivered by hand or sent by first class mail
              postage prepaid and addressed as follows:

If to EntreMed:
              President
              EntreMed, Inc.
              9640 Medical Center Drive, Suite 200
              Rockville, MD 20850

            With a copy to:

              James Dean Johnson, Ph.D.
              Jones & Askew
              2400 Monarch Tower
              2434 Peachtree Road
              Atlanta, GA 30326


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            If to Hospital:

            For all medical/scientific communications:

              Judah Folkman, M.D.
              Department of Surgery
              Children's Hospital
              300 Longwood Avenue
              Boston, MA 02115-5737

            With a copy to:

              Director
              Technology Transfer Office
              Children's Hospital
              300 Longwood Avenue
              Boston, MA 02115-5737

         For all other communications, reports, and notices:

              Director
              Technology Transfer Office
              Children's Hospital
              300 Longwood Avenue
              Boston, MA 02115-5737

       (b)    For the purpose of facilitating EntreMed's understanding of the
              research activities conducted by Hospital pursuant to the Program,
              Hospital will permit duly authorized employees or representatives
              of EntreMed to visit its facilities where the research is
              conducted, or attend restricted-access Hospital seminars on or off
              site, at reasonable times and with prior reasonable notice and
              approval by the Principal Investigator. All such visits, seminars
              or other communications, including without limitation, informal
              conversations, email and the like concerning research activities,
              will bc subject to the Mutual Nondisclosure Agreement between the
              parties of even date as this Agreement.

       (c)    All communications regarding the business terms in this Agreement
              shall be exclusively between EntreMed and the Technology Transfer
              Office.

13.    Use of Names

       (a)    Each party agrees not to use or cite in any manner the name of the
              other, its employees or Principal Investigator in any commercial
              or non-commercial advertising, article, press release or in any
              other forms of writing or publication medium, or orally to the
              extent practical, without the prior written permission of the
              party or individual whose name is to be used except as required by
              law. Hospital agrees to respond to any submission by EntreMed in a
              timely manner, and EntreMed agrees to submit such writings, and
              summarized oral comments to the extent practical, for approval at
              least ten (10) days prior to submission for public release.
              EntreMed agrees that any such writings or publications or oral
              comments or


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              presentations, and any references in its other communications to
              the public or third parties, will accurately reflect the
              contractual relationship between the parties and will not
              misrepresent or mislead others as to the nature of the
              relationship. The parties agree to meet within thirty (30) days
              alter the Effective Date to establish a set of rules to assist
              them in complying with this Article 13.(a).

       (b)    EntreMed agrees not to disclose any of Hospital's confidential or
              proprietary information in Invention disclosures or reports, data
              concerning scientific discoveries, data from evaluations, research
              results and the like in any commercial or non-commercial
              advertising, article, press release or in any other forms of
              writing or publication medium or to any third party without the
              prior written permission of Hospital.

14. Representations and Warranties. Hospital represents and warrants to EntreMed
as follows:

       (a)    The execution and delivery of this Agreement by Hospital have been
              duly and validly authorized and this Agreement constitutes a
              legal, valid and binding obligation of Hospital, enforceable in
              accordance with its terms. The execution, delivery and performance
              of this Agreement does not conflict with or violate any charter
              document or, to Hospital's knowledge, any contract binding upon
              Hospital.

       (b)    Hospital has not received notice of any assertion that any of the
              patents or subject Inventions infringe upon any third party's
              know-how, patent or other intellectual property rights, except as
              otherwise provided in writing to EntreMed, Inc.

       (c)    Hospital is and will be, during the term of this Agreement and
              thereafter, the owner of all rights in and to the inventions
              conceived or first reduced to practice by hospital or its
              employees or independent contractors as a part of and/or the
              projects which are included in the Program.

       EntreMed represents and warrants to Hospital as follows:

       (a)    The execution and delivery of this Agreement by EntreMed have been
              duly and validly authorized and this Agreement constitutes a
              legal, valid and binding obligation of EntreMed enforceable in
              accordance with its terms. The execution, delivery and performance
              of this Agreement does not conflict with or violate any charter
              document or, to EntreMed's knowledge, any contract binding upon
              EntreMed.

15.    General Provisions

       (a)    All rights and remedies hereunder will be cumulative and not
              alternative, and this Agreement shall be construed and governed by
              the laws of the Commonwealth of Massachusetts.

       (c)    Neither party may assign, transfer or delegate its rights, duties
              or obligations hereunder without the prior written consent of the
              other, and any assignment, transfer or delegation in violation of
              this provision shall be void. Subject to the terms


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              of this provision, this Agreement shall be binding upon and inure
              to the benefit of the parties hereto and their respective
              successors and assigns. Notwithstanding anything herein to the
              contrary, in the event EntreMed merges with another entity, is
              acquired by another entity, or sells all or substantially all of
              its assets to another entity, EntreMed may assign its rights and
              obligations hereunder to, in the event of a merger or
              acquisition, the surviving entity, and in the event of a sale,
              the acquiring entity, without Hospital's consent so long as: (i)
              EntreMed is not then in breach of this Agreement; (ii) the
              proposed assignee has a net worth at least equivalent to the net
              worth EntreMed had as of the date of this Agreement; (iii)
              EntreMed provides written notice of the assignment to Hospital,
              together with documentation sufficient to demonstrate the
              requirements set forth in subparagraphs (i) and (ii) above, at
              least twenty (20) days prior to the effective date of the
              proposed assignment; and (iv) Hospital receives from the proposed
              assignee, in writing, at least twenty (20) days prior to the
              effective date of the assignment an agreement to perform the
              obligations of EntreMed under this Agreement.

       (c)    This Agreement may be amended only by written agreement signed by
              both parties.

       (d)    It is expressly agreed by the parties hereto that the Hospital and
              EntreMed are independent contractors and nothing in this Agreement
              is intended to create an employer relationship, joint venture, or
              partnership between the parties. Neither party has the authority
              to bind the other.

       (e)    This Agreement and its Exhibits constitute the entire agreement
              between the parties with respect to the subject matter hereof and
              supersedes all proposals, negotiations and other communications
              between the parties, whether written or oral, with respect to the
              subject matter hereof.

       (f)    If any provisions of this Agreement shall be held to be invalid,
              illegal or unenforceable, the validity, legality and
              enforceability of the remaining provisions of this Agreement shall
              not be impaired thereby.

       (g)    The use of vertebrate animals in the conduct of work under this
              Agreement shall comply with applicable portions of the Animal
              Welfare Act (P.L. 89-544 as amended) and will follow the
              guidelines prescribed in DHEW, NIH Publication No. 78-23,
              "Guide for the Care and Use of Laboratory Animals," as amended,
              and in any applicable state or local regulations.

       (h)    EXCEPT AS PROVIDED IN ARTICLE 14, AND TO THE EXTENT PERMITTED BY
              APPLICABLE LAW, HOSPITAL MAKES NO WARRANTY, EXPRESS OR IMPLIED,
              INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES OF
              MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE OR
              NONINFRINGEMENT, WITH RESPECT TO ANY PATENT, TRADEMARK, COPYRIGHT,
              SOFTWARE, TRADE SECRET, TANGIBLE RESEARCH PROPERTY, INVENTION,
              RESEARCH RESULTS, INFORMATION OR DATA PROVIDED OR UNDER OPTION TO
              ENTREMED HEREUNDER AND HEREBY DISCLAIMS THE SAME, AND HOSPITAL
              SHALL NOT BE LIABLE FOR ANY DIRECT, CONSEQUFNTIAL OR OTHER DAMAGES
              SUFFERED BY ENTREMED OR ANY LICENSEE OR


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              OTHERS RESULTING FROM USE OF THE SAME OR ANY RESULTING PRODUCT OR
              PROCESS.

       16. 1993 Agreement

       (a)    Hospital and EntreMed hereby terminate the 1993 Agreement, except
              that Articles 5(a), 7, 8, 14(a), (c), second 14(a), and 15 shall
              survive.

       (b)    All Inventions under the 1993 Agreement shall be governed by the
              provisions of any license agreement as amended from time to time,
              entered into prior to the Effective Date, subject to Article II of
              this Agreement, or the provisions of this amended and restated
              Agreement, if no license agreement has been cxecuted as of the
              Effective Date.

       IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first written above.

<TABLE>
<CAPTION>
CHILDREN'S HOSPITAL                               ENTRMED, INC.
<S>                                               <C>
By:       /s/ William G. New                      By:  /s/ John W. Holaday, Ph.D.
          -----------------------------------          ------------------------------
            William G. New                         John W. Holaday, Ph.D.

Title:    V.P. Research Administration             Title: President and CEO
          -----------------------------------             ---------------------------

Date:     June 24, 1999                            Date: June 24, 1999
          -----------------------------------            ----------------------------




 /s/ M. Judah Folkman, M.D.                        Date: June 24, 1999
---------------------------------------------            ----------------------------
M. Judah Folkman, M.D.
</TABLE>


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