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                                                                    Exhibit 10.2


                              SUBLICENSE AGREEMENT


         THIS SUBLICENSE AGREEMENT (this "Agreement") is made effective as of
the 24th day of February, 2004 (the "Effective Date"), between Houston
Pharmaceuticals, Inc., a Texas corporation ("HPI"), and Callisto
Pharmaceuticals, Inc., a Delaware corporation ("Callisto").

                                    RECITALS

         WHEREAS, HPI and Callisto have entered into an Asset Purchase
Agreement, dated as of the date hereof (the "Purchase Agreement"), pursuant to
which Callisto has agreed to purchase the 784 Patent Rights (as defined in the
Purchase Agreement) from HPI;

         WHEREAS, HPI holds an exclusive license (subject to certain
pre-existing rights) to use the 412 Patent Rights, as defined below, pursuant to
that certain License Agreement, dated October 29, 1997, by and between HPI and
the Inventors (as defined below), attached hereto as Exhibit A;

         WHEREAS, in connection with the transactions contemplated by the
Purchase Agreement, Callisto wishes to obtain an exclusive license (subject to
certain pre-existing rights) to use the 412 Patent Rights, on the terms and
subject to the conditions set forth herein; and

         WHEREAS, the closing of the transactions contemplated by the Purchase
Agreement is conditioned upon, among other things, the execution and delivery of
this Agreement.

         NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, HPI and Callisto hereby agree as
follows:

                                    AGREEMENT

                                    ARTICLE 1
                                   DEFINITIONS

         1.1 "412 Patent Rights" shall mean (a) that certain United States
Patent number 5,874,412, issued on February 23, 1999, entitled
"Bis-Anthracyclines with high activity against doxorubicin resistant tumors,"
(b) any and all foreign (including International) patents and patent
applications that claim priority either directly or indirectly from US 5,874,412
or US Provisional Patent Application 60/013,869, (c) any provisionals,
substitutions, divisionals, reissues, renewals, continuations,
continuations-in-part, substitute applications and inventors' certificates that
claim priority either directly or indirectly from US 5,874,412 or US Provisional
Patent Application 60/013,869, and (d) any foreign or domestic patents issuing
from any of the foregoing patent applications.

         1.2 "Affiliate" shall mean any corporation or other entity that
controls, is controlled by, or is under common control with, a party. A
corporation or other entity shall be regarded as in control of another
corporation or entity if it owns or directly or indirectly controls more than
50% of the voting securities or other ownership interest of the other
corporation or entity, or if it possesses, directly or indirectly, the power to
direct or cause the direction of the management and policies of the corporation
or other entity.


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         1.3 "Licensed Process" shall mean any process that is covered in whole
or in part by an issued, unexpired valid and enforceable claim contained in the
412 Patent Rights.

         1.4 "Licensed Product" shall mean any product that is covered in whole
or in part by an issued, unexpired valid and enforceable claim in the 412 Patent
Rights.

         1.5 "Net Sales" shall mean the gross amounts received by Callisto or
its Affiliates or Sublicensees for the sale of Licensed Products to Third
Parties, less the following: (a) discounts actually granted, (b) credits,
rebates or allowances actually granted upon claims, damaged goods, rejections or
returns of Licensed Products, including recalls, (c) freight, postage, shipping
and insurance charges actually allowed or paid for delivery of Licensed
Products, to the extent billed, and (d) taxes, duties or other governmental
charges (other than income taxes) levied on, absorbed or otherwise imposed on
sales of Licensed Products.

         1.6 "Sublicensee" shall mean a third party to whom Callisto grants a
sublicense of certain rights granted to Callisto pursuant to this Agreement.

         1.7 "Term" means the period of time beginning on the date hereof and
ending upon the expiration of the last to expire of the 412 Patent Rights.

         1.8 "Third Party" shall mean any entity other than Callisto or HPI or
an Affiliate of Callisto or HPI.

                                   ARTICLE 2
                                     GRANTS

         2.1 License. Subject to the terms and conditions of this Agreement, HPI
hereby grants to Callisto an exclusive, world-wide, royalty-bearing right
(subject to certain pre-existing rights described below) to make, have made,
use, lease, sell and import the Licensed Products and to practice the Licensed
Processes and the 412 Patent Rights during the Term. Callisto agrees to practice
the license granted under this Section 2.1 in accordance with all applicable
laws, regulations and governmental guidelines.

         2.2 Sublicense. Subject to the terms and conditions of this Agreement,
HPI hereby grants to Callisto an exclusive right to enter into sublicensing
agreements with any other entity for the rights, privileges and licenses granted
hereunder. Upon any termination of this Agreement, Sublicensees' rights shall
also terminate, subject to Section 8.5 of this Agreement. With respect to any
sublicenses granted pursuant to this Section 2.2, Callisto shall (a) include all
of the rights and obligations due to HPI or any other party under the terms of
this Agreement, and (b) collect and guarantee payment of all payments due,
directly or indirectly, from Sublicensees to HPI or any other party based on the
terms of this Agreement or any sublicense.

         2.3 Pre-existing Rights. Any rights granted pursuant to this Agreement
are explicitly made subject to those rights retained by the University of Texas
System pursuant to that certain Assignment, executed by the University of Texas
System in favor of Waldemar Priebe, Jonathan B. Chaires, Teresa Przewloka,
Izabela Fokt, and Roman Perez-Soler (together, the "Inventors") on October 8,
1998 (the "Assignment"). Under the terms of the Assignment, the University of
Texas System and its components hold a royalty-free, non-exclusive license to
use the 412 Patent Rights in educational, research and patient-care activities.


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                                   ARTICLE 3
                                  Consideration

         3.1 License Fee. In consideration of the license granted to Callisto by
HPI, Callisto shall pay to HPI the consideration described in Sections 1.3(a)
and 1.3(c) of the Purchase Agreement.

         3.2 Royalty. In addition to the consideration payable to HPI pursuant
to Section 3.1, Callisto agrees to pay to HPI a royalty equal to two percent
(2%) of Net Sales of Licensed Products.

         3.3 Manner and Place of Royalty Payments. All royalty payments
hereunder shall be payable in U.S. dollars on a bi-annual basis, beginning on
the first day of the sixth calendar month following the first sale of a Licensed
Product.

                                   ARTICLE 4
                     REPRESENTATIONS; WARRANTIES; COVENANTS

         4.1 Licensing Rights. HPI represents and warrants that it has the legal
right to grant the license granted under Section 2 of this Agreement.

         4.2 Corporate Power; Due Authorization. Each party hereto represents
and warrants that it is duly organized, validly existing and in good standing
under the laws of the state or other jurisdiction of its incorporation or
formation and has full power and authority to execute and deliver this Agreement
and to perform its obligations hereunder.

         4.3 Binding Agreement. Each party hereby represents and warrants that
this Agreement is a valid obligation binding upon it and is enforceable in
accordance with its terms. The execution, delivery and performance of this
Agreement by such party does not (a) contravene or conflict with its
organizational documents, (b) to its knowledge, contravene or conflict with or
constitute a material violation of any provision of any applicable legal
requirement binding upon or applicable to such party or (c) contravene or
constitute a default under any material contract of the party, in the case of
each of (a), (b) and (c), except as would not have a material adverse effect on
such party.

         4.4 Development and Commercialization Efforts. From and after the date
hereof, Callisto shall use its commercially reasonable efforts to develop and
commercialize at least one drug candidate resulting from the 412 Patent Rights
that meet Callisto's criteria for clinical development. Callisto shall have the
sole ownership in and to any and all intellectual property rights resulting from
Callisto's development efforts (the "Developments"). In the event that HPI
exercises its right to terminate this Agreement pursuant to Section 6 by reason
of Callisto's material breach of this Section 4.4 or as a result of a
determination by Callisto's Board of Directors to abandon its development and
commercialization efforts with respect to the 412 Patent Rights, Callisto agrees
to grant HPI, on commercially reasonable terms, a non-exclusive license to use
any of the Developments that, in the mutual determination of Callisto and HPI,
are necessary to enable HPI to develop and commercialize any drug candidates
resulting from the 412 Patent Rights.


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         4.5 Assignment of 412 Patent Rights. From and after the date hereof,
HPI shall use its commercially reasonable efforts to facilitate the assignment
of all of the Inventors rights, title and interest in and to the 412 Patent
Rights to Callisto on terms mutually agreed upon by the Inventors and Callisto.
The reasonable expenses incurred by HPI while acting pursuant to this Section
4.5 shall be borne by Callisto; provided, however, that Callisto shall not be
required to reimburse HPI for more than $2,500 in expenses pursuant to this
Section 4.5, and HPI shall not be obligated to incur any out-of-pocket costs
pursuant to this Section 4.5 unless such costs are subject to reimbursement by
Callisto.

         4.6 Disclaimer of Warranties. EXCEPT AS EXPRESSLY SET FORTH IN THIS
AGREEMENT, NEITHER PARTY MAKES ANY REPRESENTATION OR WARRANTY TO THE OTHER PARTY
OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING, WITHOUT LIMITATION, ANY WARRANTY OF
TITLE, NON-INFRINGEMENT, MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

         4.7 Indemnification. Callisto shall indemnify, hold harmless and defend
HPI and the Inventors against any and all claims, suits, losses, damage, costs,
fees, and expenses resulting from or arising out of Callisto's exercise of the
license or any sublicense granted pursuant to this Agreement. This
indemnification shall include, but not be limited to, any product liability.

         4.8 Limitation of Liability. NEITHER PARTY SHALL BE ENTITLED TO RECOVER
FROM THE OTHER PARTY ANY SPECIAL, INCIDENTAL, EXEMPLARY, CONSEQUENTIAL OR
PUNITIVE DAMAGES IN CONNECTION WITH THIS AGREEMENT.

                                   ARTICLE 5
                        PATENT MAINTENANCE; INFRINGEMENT

         5.1 Maintenance. Callisto shall diligently prosecute and maintain the
United States and foreign patents and applications in the 412 Patent Rights at
its sole expense using counsel of its choice. Callisto shall provide HPI, upon
request, with copies of all relevant documentation relating to such prosecution
and HPI shall keep this documentation confidential. All patents and patent
applications in the 412 Patent Rights shall be assigned solely to the Inventors
(excluding applications, such as continuation in part applications,
incorporating new matter).

         5.2 Infringement.

              (a) If HPI learns of any substantial infringement of the 412
Patent Rights, HPI shall so inform Callisto. During the Term, Callisto shall
have the right to prosecute in its own name and at its own expense any
infringement of any of the 412 Patent Rights. HPI or the Inventors may
voluntarily join such suit and may be represented by counsel of their choice,
each at their own expense. Callisto may not join HPI or the Inventors in a suit
initiated by Callisto without such party's prior written consent, provided,
however, that if HPI or the Inventors are determined by a court to be a
necessary or required party in any such suit, then no consent shall be required.
If, in a suit initiated by Callisto, HPI or the Inventors are involuntarily
joined other than by Callisto, or if HPI or the Inventors are joined because
they are deemed to be a necessary or required party, then Callisto will pay the
reasonable costs incurred by HPI or the Inventors, as applicable, arising out of
such suit, including but not limited to, any reasonable legal fees of counsel
that HPI or the Inventors select and retain to represent them in the suit.


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              (b) Recoveries from actions brought by Callisto pursuant to
Paragraph 5.2(a) shall belong to the Callisto, provided, however, that the
amount by which such recoveries exceed Callisto's expenses for such actions
shall be subject to the royalty in Section 3.2 above as if the net amount of any
such recovery is considered to be "Net Sales." In the event that Callisto does
not elect to exercise its right to prosecute an infringement on the 412 Patent
Rights pursuant to this Section 5.2, after written consent by Callisto, which
such consent shall not be unreasonably withheld or delayed, HPI may do so at its
own expense, controlling such action. In the event that HPI does not elect to
exercise its right to prosecute an infringement on the 412 Patent Rights
pursuant to this Section 5.2, then the Inventors may do so at their own expense,
controlling such action. Recoveries from such actions brought by HPI or the
Inventors shall belong entirely to HPI or the Inventors, as applicable.

              (c) Each party shall cooperate with the other in litigation
proceedings at the expense of the party bringing suit. Litigation shall be
controlled by the party bringing the suit, except that HPI and the Inventors may
be represented by counsel of their choice in any suit brought by Callisto.

                                    ARTICLE 6
                                   Termination

6.1      Termination by HPI.

              (a) If Callisto materially violates any term of this Agreement,
then HPI may give written notice of default ("Notice of Default") to Callisto.
If Callisto fails to cure the default within forty-five (45) days of the Notice
of Default, HPI may terminate this Agreement and the license granted herein
prior to the expiration of the Term by a second written notice ("Notice of
Termination") to Callisto. If a Notice of Termination is sent to Callisto, this
Agreement shall automatically terminate on the effective date of that notice.
Termination shall not relieve Callisto of its obligation to pay any fees owed at
the time of termination and shall not impair any accrued right of HPI or the
Inventors.

              (b) If the Board of Directors of Callisto shall determine to
abandon its development and commercialization efforts with respect to the 412
Patent Rights, Callisto shall notify HPI in writing within 10 days of the
Board's determination and HPI shall have the right to terminate this Agreement
prior to the expiration of the Term at any time upon thirty (30) days' prior
written notice to Callisto. Any sublicense of the 412 Patent Rights by Callisto
in accordance with the terms of this Agreement shall not trigger HPI's right to
terminate this Agreement so long as under the terms of any such sublicense,
Callisto retains the right to terminate such sublicense if the Sublicensee fails
to use its commercially reasonable efforts to develop and commercialize at least
one drug candidate resulting from the 412 Patent Rights that meets the
Sublicensee's criteria for clinical development. Callisto shall promptly
exercise its right to terminate if it learns that any Sublicensee of the 412
Patent Rights has failed to use its commercially reasonable efforts to develop
and commercialize at least one drug candidate resulting from the 412 Patent
Rights that meets the Sublicensee's criteria for clinical development and upon
such termination, shall promptly provide written notice to HPI (the "Notice").
HPI shall have the right to terminate this Agreement by written notice to
Callisto within forty-five (45) after receipt of the Notice by HPI.


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         6.2 Termination by Callisto.

              (a) Callisto shall have the right at any time and for any reason
to terminate this Agreement prior to the expiration of the Term upon thirty (30)
days' prior written notice to HPI. Said notice shall state Callisto's reason for
terminating this Agreement.

              (b) Any termination under Section 6.2(a) shall not relieve
Callisto of any obligation or liability accrued under this Agreement prior to
termination or rescind any payment made to HPI or the Inventors or action by
Callisto prior to the time termination becomes effective. Termination shall not
affect in any manner any rights of HPI or the Inventors arising under this
Agreement prior to termination.

         6.3 Effect of Termination. Within sixty (60) days following the
expiration or termination of this Agreement, each party shall return to the
other party, or destroy, upon the written request of the other party, any and
all confidential information of the other party in its possession and shall
provide such other party with written certification to that effect, executed by
a duly authorized representative of such party.

                                   ARTICLE 7
                                  MISCELLANEOUS

         7.1 Assignment. Except as expressly provided hereunder, neither this
Agreement nor any rights or obligations hereunder may be assigned or otherwise
transferred by either party without the prior written consent of the other party
(which consent shall not be unreasonably withheld). The rights and obligations
of the parties under this Agreement shall be binding upon and inure to the
benefit of the successors and permitted assigns of the parties. Any assignment
not in accordance with this Agreement shall be void.

         7.2 Notices. All notices and other communications provided for
hereunder shall be in writing and shall be mailed by first-class, registered or
certified mail, postage paid, or delivered personally, by overnight delivery
service or by facsimile, with confirmation of receipt, addressed as follows:

         If to HPI:                         HOUSTON PHARMACEUTICALS, INC.
                                            4239 Emory Avenue
                                            Houston, TX 77005
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         If to Callisto:

                  Either party may by like notice specify or change an address
to which notices and communications shall thereafter be sent. Notices sent by
facsimile shall be effective upon confirmation of receipt, notices sent by mail
or overnight delivery service shall be effective upon receipt, and notices given
personally shall be effective when delivered.

         7.3 Governing Law. This Agreement shall be governed by, and construed
and enforced in accordance with, the laws of the State of New York, U.S.A., as
such laws apply to agreements between New York residents performed entirely
within the State of New York.

         7.4 Waiver. Except as specifically provided for herein, the waiver from
time to time by either party of any right or failure to exercise any remedy
shall not operate or be construed as a continuing waiver of the same right or
remedy or of any other of such party's rights or remedies provided under this
Agreement.

         7.5 Severability. In case any provision of this Agreement shall be
invalid, illegal or unenforceable, the validity, legality and enforceability of
the remaining provisions shall not in any way be affected or impaired thereby.

         7.6 Independent Contractors. It is expressly agreed that Callisto and
HPI shall be independent contractors and that the relationship between the two
parties shall not constitute a partnership, joint venture or agency of any kind.
Neither party shall have the authority to make any statements, representations
or commitments of any kind, or to take any action, which shall be binding on the
other party, without the prior written consent of the other party.

         7.7 Entire Agreement; Amendment. This Agreement sets forth all of the
agreements and understandings between the parties hereto with respect to the
subject matter hereof, and supersedes and terminates all prior agreements and
understandings between the parties with respect to the subject matter hereof,
other than the Purchase Agreement. There are no agreements or understandings
with respect to the subject matter hereof, either oral or written, between the
parties other than as set forth herein. Except as expressly set forth in this
Agreement, no subsequent amendment, modification or addition to this Agreement
shall be binding upon the parties hereto unless reduced to writing and signed by
the respective authorized officers of the parties.

         7.8 Headings. The captions contained in this Agreement are not a part
of this Agreement, but are merely guides or labels to assist in locating and
reading the several Articles hereof.

         7.9 Counterparts. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.



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


HOUSTON PHARMACEUTICALS, INC.           CALLISTO PHARMACEUTICALS, INC.


By: /s/Teresa Priebe                    By: /s/ Gary Jacob
    --------------------------------        ---------------------------------

Name: Teresa Priebe                     Name: Gary Jacob
      ------------------------------          -------------------------------

Title: President                        Title: Chief Executive Officer
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