CONSULTING AGREEMENT

     THIS CONSULTING AGREEMENT (this "Agreement"), entered into as of the 8th
day of May, 2006 (the "Effective Date"), by and between VION PHARMACEUTICALS,
INC., a Delaware corporation having offices at Four Science Park, New Haven,
Connecticut 06511 (the "Corporation") and MARIO SZNOL, M.D., an individual
having an office at 186 Rimmon Rd., Woodbridge, CT 06525 ("Consultant").

     In consideration of the services provided hereunder for the Corporation by
Consultant, Consultant and the Corporation hereby agree as follows:

     1. Consulting Services. Consultant shall work on a day-to-day basis with
the Clinical Affairs group of the Corporation. Consultant shall report to the
Chief Executive Officer and shall perform such consulting services for the
Corporation as may be requested by the Chief Executive Officer, including, but
not limited to, the following:

     (a) Participating in the review of data derived from the pre-clinical and
clinical development programs and assisting in the preparation of reports and
publications; and

     (b) Participating in meetings with the U.S. Food and Drug Administration
and with Canadian and European regulatory authorities, assisting the Corporation
in its preparation for ODAC reviews.

     All such consulting services are collectively referred to herein as the
"Services". Consultant shall provide Services on a per diem basis during the
term of this Agreement, such days to be at the mutual convenience of the
Corporation and Consultant. Consultant shall be available for consultation with
the Corporation by correspondence or telephone, and, when necessary, by meetings
at such times and locations, including the Corporation's offices in New Haven,
Connecticut, as may be reasonably requested by the Corporation.

     2. Term. The term of this Agreement shall commence on the Effective Date
and expire on December 31, 2008. The term of this Agreement may be extended by
mutual agreement of the parties. Notwithstanding the foregoing, this Agreement
may be terminated at any time by the Corporation or Consultant by giving written
notice to the other party. Upon termination, the Consultant shall not incur any
further time charges or expenses on behalf of the Corporation and the
Corporation shall be obligated to pay time charges and expenses incurred prior
to termination subject to the limitations in this Agreement. Notwithstanding any
termination of this Agreement, the obligations of Consultant under Sections 4
and 5 hereof shall survive any such termination.

     3. Compensation. In consideration of the Services performed by Consultant
hereunder, Consultant shall receive compensation as follows:

     (a)  The Corporation shall pay Consultant the sum of One Thousand Five
          Hundred Dollars ($1,500.00) per full day of service. For purposes of
          this Agreement, a "full day" shall be deemed to mean any eight hour
          period of service. Fees shall be prorated for any period of less than
          eight hours at the rate of $187.50 per hour.



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     (b)  The Corporation shall reimburse Consultant for reasonable
          out-of-pocket travel, hotel and other business expenses incurred at
          the request of the Corporation as soon as practicable following
          submission of statements of expenses incurred, accompanied by
          appropriate supporting documentation, but no more than thirty (30)
          days following such submission.

     4. Confidential Information. Consultant acknowledges that during the term
of this Agreement, he may be exposed to secret and confidential information of
the Corporation and those of other companies with whom the Corporation does
business on a confidential basis. While such information will normally be marked
as confidential, Consultant realizes that all information about unreleased
products and other non-public information about the Corporation is a valuable
trade secret of the Corporation, disclosure of which could severely damage the
economic interests of the Corporation. Confidential information shall also
include the Corporation's proprietary products and drug-delivery techniques,
reports, interpretations, forecasts, records, trade secrets, strategies,
studies, data and know-how, techniques, marketing plans and opportunities, cost
and pricing data, customer lists, developments, improvements, discoveries,
technologies, processes, research, methods, procedures, designs, models, testing
systems, assays, compounds, molecules, organisms, computer software and programs
(including source code and related documentation), test, trial and/or
experimental data and results, laboratory notebooks, drawings and technical
information and materials. Consultant agrees not to disclose such confidential
information, either during the term of this Agreement or at any time thereafter,
to any person not employed by the Corporation, or not engaged to render services
to the Corporation, except with the prior written consent of the Board of
Directors of the Corporation, or if such information is required to be disclosed
because of subpoena or other requirement of law, until such time as the
information becomes public knowledge through no fault of their own. The
agreement made in this paragraph 4 shall be in addition to, and not in
limitation or derogation of, any obligations otherwise imposed by law or by
separate agreement upon Consultant in respect of confidential information of the
Corporation.

     Consultant hereby acknowledges that the Corporation would be irreparably
damaged if such information was disclosed to, or utilized on behalf of, others
in competition in any respect with the Corporation or companies in which it
invests, which damage cannot be adequately compensated for by an action at law.
In the event of a breach or threatened breach by Consultant of the provisions
hereof, Consultant agrees that the Corporation shall be entitled to an
injunction restraining them from such breach. Consultant hereby waives any right
to object to the Corporation's efforts to obtain such an injunction. Nothing
herein contained shall be construed as prohibiting the Corporation from pursing
any other remedies available at law or in equity for any breach or threatened
breach of this Agreement.

     Consultant hereby acknowledges that confidential, non-public information is
"inside information" under the securities laws of the United States and should
not be provided to any person that may trade in the Corporation's securities.

     5.   Inventions.

     (a) Consultant agrees that the Corporation is the sole owner of all right,
title and interest in all improvements, processes, products, technical
information, discoveries ideas, original works of authorship, developments,
trade secrets and work products and related material


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that are developed for or in conjunction with, or paid for by, the Corporation
in connection with the performance of any Services provided by Consultant before
or after the date hereof (collectively, "Consultant Inventions"). Consultant
shall promptly disclose to the Corporation any and all Consultant Inventions,
whether or not patentable, which Consultant conceives or makes, solely or
jointly, within the term of this Agreement and which are related specifically to
Services rendered under this Agreement, or as a result of the receipt of
confidential information from the Corporation;

     (b) Consultant shall promptly grant, assign and convey to the Corporation
(or its designee) all his rights in and to such Consultant Inventions, and, upon
request, at the Corporation's expense, promptly execute all applications,
assignments or other instruments which the Corporation (or its designee) shall
deem necessary in order to apply for and obtain invention rights, patents,
patent applications, letters patent, copyrights and reissues thereof ("Rights")
in the Untied States and foreign countries on said Consultant Inventions, in
order to assign and convey to the Corporation (or its designee) the sole and
exclusive rights, title and interest in and to Consultant's right in and to said
Consultant Inventions and Rights;

     (c) The Corporation (or its designee) will bear the cost of patent
applications and assignments and the cost of prosecution of all such patent
applications in the Untied States Patent Office and in the patent offices of
foreign countries; and

     (d) Consultant shall render to the Corporation (and its designee) other
assistance as it may require in the prosecution of Rights, in the prosecution or
defense of interferences which may be declared involving any of said Rights, and
in any litigation in which the Corporation may be involved relating to such
Rights, provided that Consultant shall be entitled to additional compensation,
at an hourly fee reasonable and customary for a consultant of similar experience
and qualifications, for any consultation or testimony provided pursuant to this
Section 5(d).

     6. Competitive Employment. The Corporation acknowledges that Consultant is
free to provide consulting services or pursue employment or business
opportunities with companies, institutions and other entities other than the
Corporation; provided that, such other companies, institutions and other
entities do not compete, either directly or indirectly, with the Corporation.

     7. Representation of Consultant. Consultant represents and warrants that he
is permitted to enter into this Agreement and that the terms of this Agreement
are not inconsistent with and are not in violation of his other contractual
obligations. The Corporation recognizes that Consultant's activities are and
will be subject to the policies, rules and regulations of Yale University
("Institute Policy") and the Corporation agrees that Consultant shall be under
no obligation to perform Services if such performance would conflict with
Institute Policy. In the event of a conflict, Institute Policy shall control.

     8. Independent Contractor. Consultant's relationship with the Corporation
shall be that of an independent contractor, and Consultant shall not be deemed
an employee of the Corporation for any purpose whatsoever.

     9. Indemnification. The Corporation shall hold harmless, indemnify and
defend Consultant against any and all third-party claims, liabilities, losses,
costs or expenses (including reasonable attorney's fees) arising out of or in
connection with the Services under this Agreement unless such claims,
liabilities, losses, costs or expenses arise from an act or omission


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by Consultant constituting willful misconduct, gross negligence, self dealing or
fraud, or an act or omission the payment of indemnification for which is
prohibited by law.

     10. Notices. Any notice of other communication hereunder shall be in
writing, shall be given either manually or by mail, addressed to the party to be
notified at its address first set forth above, and shall be deemed sufficiently
given as of the third day thereafter. Either party may, by notice to the other,
change its address for receiving such notices and communications.

     11. Assignability. This Agreement shall inure to the benefit of any
assignee of the Corporation, and Consultant specifically agrees on demand to
execute any and all reasonably necessary documents in connection therewith. This
Agreement may not be assigned by Consultant.

     12. Entire Agreement. This Agreement constitutes the entire understanding
of the parties hereto with reference to the subject matter hereof and shall not
be changed or modified except by a written instrument signed by both parties;
provided that, this Agreement shall not supersede the Proprietary Information
and Inventions Agreement, dated February 5, 2001 with respect to Consultants
prior service as an employee of the Corporation.

     13. Governing Law. This Agreement shall be governed by and construed in
accordance with the laws of the State of Connecticut, without regard to its
conflicts of laws principles.

     14. Counterparts. This Agreement may be executed in any number of
counterparts, and each counterpart hereof shall be deemed an original
instrument, but all such counterparts together shall constitute but one
agreement.

     IN WITNESS WHEREOF, this Agreement has been executed by the parties hereto,
as of the day and year first above written.

                                                  VION PHARMACEUTICALS, INC.


                                                  By: /s/ Alan Kessman
                                                      --------------------------
                                                  Name: Alan Kessman
                                                  Title: Chief Executive Officer


                                                  CONSULTANT

                                                  By: /s/ Mario Sznol, MD
                                                      --------------------------
                                                  Name: MARIO SZNOL, MD





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