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                                                                    EXHIBIT 10.4



                         CYTRX CORPORATION/ARAIOS, INC.

                       SCIENTIFIC ADVISORY BOARD AGREEMENT

      This Scientific Advisory Board Agreement (the "Agreement") dated as of
January 20, 2004 is made by Tariq M. Rana, Ph.D. (the "SAB Member"), CytRx
Corporation, a Delaware corporation ("CytRx") and Araios, Inc., a Delaware
corporation and subsidiary of CytRx ("Araios"), with CytRx and Araios being
collectively referred to as the "Companies".

                                    AGREEMENT

      1.    GENERAL. Effective as of the date of execution of this Agreement by
all parties, the approval of this Agreement by the Principal Institution
(defined below), and the execution of Schedule A hereto by all parties thereto,
with such date to be indicated below the signature of the SAB Member on the
signature page of this Agreement (the "Effective Date"), each of the Companies
shall retain the SAB Member, and the SAB Member agrees to serve, as a member of
both of the Companies' respective Scientific Advisory Boards ("SAB") and to
consult with the Companies in the Field (as hereinafter defined). The SAB Member
agrees to provide to each of the Companies such services in the Field as are
customarily performed by a member of a scientific advisory board to a company
such as the Companies (the "Services"). The Services will include, without
limitation:

      -     Consulting with each of the Companies' respective management within
            the SAB Member's professional area of expertise from time to time as
            reasonably requested by either of the Companies;

      -     Exchanging strategic and business development ideas with the
            Companies;

      -     Attending scientific, medical or business meetings with the
            Companies' management, such as United States Food & Drug
            Administration meetings, meetings with strategic or potential
            strategic partners and other meetings relevant to SAB Member's area
            of expertise; and

      -     Attending meetings of the SAB as provided herein.

      For purposes of this Agreement, the term "Field" means the use of RNAi
technology in, or the application of RNAi technology to, the discovery or
development of therapeutic products for humans or animals, and/or the use of
RNAi as a component of therapeutic products for humans or animals.
Notwithstanding anything else herein to the contrary, the term "Field" is
specifically understood to not include the use of RNAi technology in, or the
application of RNAi technology to, the discovery and development of reagents,
diagnostic products, agricultural products, or products or services developed
for or offered to the research tools and products market, or the use of RNAi as
a component of reagents, diagnostic products, agricultural products, or products
or services developed for or offered to the research tools and products market.
The Services shall not include those services prohibited by the Principal
Institution, including as set forth in "The University of Massachusetts Uniform
Consulting Agreement Provisions" attached hereto as Exhibit A and incorporated
herein (the "UMass Provisions") or

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any Affiliated Institution (as defined in Section 2 hereof). The SAB Member is
agreeing to provide the Services under this Agreement in consideration of the
compensation provided in Section 3 hereof.

      2.    PERFORMANCE OF SERVICES. As of the Effective Date, the SAB Member
agrees to make himself available to render the Services, at such time or times
and location or locations as may be mutually agreed, from time to time at the
request of the respective Companies and subject to the UMass Provisions. The SAB
Member agrees not to perform any Services for the respective Companies on the
premises of the University of Massachusetts Medical School (the "Principal
Institution"), any academic institution or any hospital with which he is or may
become affiliated (each such Principal Institution, academic institution and
hospital an "Affiliated Institution") or with the respective facilities or funds
of any such Affiliated Institution which could result in claims by such
Affiliated Institution of rights in any Inventions (as defined in Section 8
hereof), without the express prior agreement of the Companies and the Affiliated
Institution, as appropriate. Unless covered by an appropriate agreement between
any third party (other than an Affiliated Institution) and the respective
Companies, the SAB Member shall not knowingly engage in any activities or use
any facilities in the course of providing Services which could result in claims
of ownership to any Inventions being made by such third party. The SAB Member
agrees to devote his reasonable and diligent efforts to the performance of the
Services. The SAB Member agrees to attend at least four Araios SAB meetings and
two CytRx SAB meetings per year.

      3.    COMPENSATION.

            (A)   UP-FRONT CASH PAYMENT AND GRANT OF OPTION. The Companies will
compensate the SAB Member for serving as a member of the CytRx SAB and Araios
SAB and for providing the Services to the Companies as follows:

                  (1)   Upon the Effective Date and confirmation from the SAB
Member that he is permitted to commence providing the Services without violating
any other contractual arrangement by which he is bound, the Companies shall pay
the SAB Member a total of $50,000 in cash.

                  (2)   No later than the signing of this Agreement by the SAB
Member and the Companies, CytRx shall grant the SAB Member a nonqualified stock
option (the "Option") under the CytRx 2000 Long-Term Incentive Plan to purchase
up to 812,500 shares (the "Option Shares") of common stock of CytRx. The Option
shall have an exercise price equal to the closing price of CytRx common stock on
the Effective Date, as reported on Nasdaq. The Option shall be for a term of ten
years and shall otherwise be in the form of the Nonqualified Stock Option
Agreement attached hereto as Exhibit B and incorporated herein by reference.
Vested Options shall not be subject to lapse for any reason prior to the end of
their ten year term. The Company covenants and agrees that it will file an
effective Form S-8 registration statement covering the Option and the Options
Shares no later than April 15, 2004, such that from and after the date of filing
(and in all events no later than April 15, 2004) the Option Shares shall be
freely tradable immediately upon any exercise of the Option. The Option may be
exercised pursuant to a cashless exercise, but only if the SAB Member is not
able at the time to obtain the cash proceeds for the exercise price in a
broker's transaction (with the Companies bearing any

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commission expenses charged by the broker in connection with selling sufficient
shares to generate the cash proceeds for the exercise price).

            (B)   VESTING OF OPTION. The Option shall be vested and exercisable
immediately upon the Effective Date as to 500,000 of the Option Shares and shall
vest and become exercisable as to the balance of the Option Shares as follows:
(i) as to 62,500 of such Option Shares if, during the Term (as defined in
Section 5 hereof) or within one year thereafter (the "Tail Period"), either of
the Companies or any of their respective affiliates or successors enters into a
strategic alliance, collaboration, joint venture or similar arrangement with a
Major Pharmaceutical Company (as defined below) for the development or
Commercialization of an RNAi Product (as hereinafter defined) (a "Strategic
Alliance"); (ii) as to any and all unvested Option Shares if, during the Term or
during the Tail Period, either of the Companies or any of their respective
affiliates, successors or strategic partners or licensees commences commercial
sales of any RNAi Product in the United States, the European Union nations or
Japan ("Commercialization"); and (iii) as to any and all unvested Option Shares
if during the Term or during the Tail Period, CytRx consummates a Sale (as
defined below).

            (C)   CERTAIN DEFINITIONS. For purposes of this Agreement:

                  (1)   The term "Major Pharmaceutical Company" means (i) any of
the 50 largest pharmaceutical/bio-pharmaceutical/biotechnology companies
worldwide as measured by market capitalization, or (ii) any
pharmaceutical/bio-pharmaceutical/biotechnology company with revenues from
product sales in excess of $3 billion.

                  (2)   The term "Sale" means (i) a consolidation or merger of
CytRx into or with any other entity or entities which results in the exchange of
outstanding shares of CytRx for securities or other consideration issued or paid
or caused to be issued or paid by any such entity or affiliate thereof (other
than a merger or consolidation in which the holders of outstanding shares of
CytRx become, solely by means of such merger or consolidation, the holders of a
majority of the voting securities of such other entity), or (ii) a sale, lease,
transfer or other disposition to an unaffiliated third party by CytRx or Araios
of all or substantially all of its respective assets or voting securities, or of
all or substantially all of the assets or voting securities of that Company.

                  (3)   The term "RNAi Product" means any human or animal
therapeutic product that (i) is discovered or developed through the use or
application of RNAi technology, or (ii) contains RNAi as a component thereof.

                  (4)   Notwithstanding the definition of the term "Tail Period"
in Section 3(B), in the event that (i) the Companies terminate this Agreement
without Cause (as hereinafter defined), or (ii) the SAB Member terminates this
Agreement for Good Reason (as hereinafter defined), then the Tail Period shall
be extended so as to be that period which is the longer of one year from the
date of termination or six years from the Effective Date. Notwithstanding
anything herein to the contrary, the Tail Period shall not be extended under
this Section 3(C)(4) in the event of a termination of this Agreement by either
party under Section 4 or 6(E).

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            (D)   MONTHLY CONSULTING FEE. In addition to the foregoing $50,000
payment and grant of the Option, for his Services hereunder the SAB Member shall
be entitled to a total monthly payment from the Companies of $6,667 for each
month during the Term, payable monthly in arrears, which will increase to $7,500
per month upon Commercialization, a Strategic Alliance or a Sale.

            (E)   EXPENSES. The respective Companies also shall promptly
reimburse the SAB Member for reasonable out-of-pocket expenses, including,
without limitation, travel expenses incurred by him in the performance of the
Services (including attendance at all SAB meetings), following the respective
Companies' receipt of a request for reimbursement from the SAB Member. The SAB
Member shall promptly provide the respective Companies with documentation
supporting all such expenses.

      4.    PRINCIPAL INSTITUTION. The Companies recognize that the activities
of the SAB Member are or will be subject to the rules and regulations of the
Principal Institution and any other Affiliated Institution, now or in the
future, and the Companies agree that SAB Member shall be under no obligation to
perform Services if such performance would conflict with such rules and
regulations, or constitute a conflict of interest under the relevant policies of
the Affiliated Institution. The SAB Member has no reason to believe that the SAB
Member's performance of any of the services contemplated by this Agreement will
conflict with the applicable rules or policies of any Affiliated Institution,
each as presently in effect. In the event such rules and regulations shall, in
the Companies' reasonable opinion or the reasonable opinion of the SAB Member,
substantially interfere with the performance of Services by the SAB Member, the
Companies or the SAB Member may terminate this Agreement upon 30 days notice to
the other parties. Any such termination by the Companies shall not be considered
a termination for Cause, unless the Affiliated Institution's rules or policies
that are asserted by the Companies or the SAB Member to be in conflict with the
performance of the Services are rules or policies that are not generally applied
by that Affiliated Institution to other academic researchers at that
institution. The SAB Member shall provide copies to the Companies of all status
reports he delivers and other material correspondences he has with any
Affiliated Institution concerning this Agreement or the Services within three
business days of his delivery or receipt of such report or correspondence,
provided that the policies of any Affiliated Institution permit him to do so,
and provided further that the Companies agree to hold any such report or
correspondence in confidence.

      5.    TERM. The SAB Member's performance of Services shall commence on the
Effective Date and shall continue for a period of five years thereafter (such
period, including any extension of such period, the "Term"), unless either the
SAB Member or either of the Companies terminate this Agreement pursuant to
Sections 4 or 6 hereof, or unless this Agreement is extended by the mutual
written agreement of the SAB Member and the Companies.

      6.    TERMINATION; EFFECT OF TERMINATION.

            (A)   TERMINATION BY COMPANIES FOR CAUSE. The Companies may
terminate this Agreement (in addition to any other available remedy) at any time
for Cause. The term "Cause" shall mean the SAB Member's material failure to
perform his duties under this Agreement which goes uncured for more than 15 days
following written notice from either of the

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Companies, the SAB Member's conviction of or plea of no contest to any felony,
or the SAB Member's act or failure to act that materially and adversely affects
the business of either of the Companies.

            (B)   TERMINATION BY SAB MEMBER FOR GOOD REASON. The SAB Member may
terminate this Agreement (in addition to any other available remedy) at any time
for Good Reason. The term "Good Reason" shall mean (i) either of the Companies'
breach any of its material obligations under this Agreement in any material
respect (including without limitation, the Companies' payment obligations and
CytRx's obligations with respect to the Option and the Option Shares) if such
breach is not cured within 15 days (10 days in the case of a breach of a payment
obligation) after receipt by such party of written notice thereof, or (ii) the
occurrence any of the following events upon not less than 15 days prior written
notice to the Companies at any time after the occurrence of such events, but in
no event later than 60 days after written notice from the Companies to the SAB
Member of the occurrence of any of such events:

      -     a decree, judgment, or order by a court of competent jurisdiction
            shall have been entered adjudging both of the Companies as bankrupt
            or insolvent, or approving as properly filed a petition seeking
            reorganization of both of the Companies under any bankruptcy or
            similar law, and such decree of order shall have continued
            undischarged and unstayed for a period of 60 days; or a decree or
            order of a court of competent jurisdiction ordering the appointment
            of a receiver, liquidator, trustee, or assignee in bankruptcy or
            insolvency of both of the Companies, or for the winding up or
            liquidation of the affairs of both of the Companies, shall have been
            entered, and such decree, judgment, or order shall have remained in
            force undischarged and unstayed for a period of 60 days;

      -     both of the Companies shall institute proceedings to be adjudicated
            a voluntary bankrupt, or shall consent to the filing of a bankruptcy
            proceeding against it, or shall file a petition or answer or consent
            seeking reorganization under any bankruptcy or similar law or
            similar statute, or shall consent to the filing of any such
            petition, or shall consent to the appointment of a custodian,
            receiver, liquidator, trustee, or assignee in bankruptcy or
            insolvency of it or any of its assets or property, or shall make a
            general assignment for the benefit of creditors, or shall admit in
            writing its inability to pay its debts generally as they become due;
            or

      -     the Companies and their affiliates shall discontinue or suspend
            indefinitely substantially all research and development efforts in
            the Field.

            (C)   TERMINATION BY COMPANIES WITHOUT CAUSE; TERMINATION BY SAB
MEMBER WITHOUT GOOD REASON. The Companies or the SAB Member may terminate this
Agreement at any time after three years from the Effective Date (but not before
then) without cause and without liability to any other party upon 15 days prior
written notice to the Companies or the SAB Member, as the case may be.

            (D)   TERMINATION DUE TO DEATH OR DISABILITY. This Agreement shall
automatically terminate upon the death of the SAB Member, or upon notice from
the Companies

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or the SAB Member following the "Disability" of the SAB Member. For purposes of
this Agreement, the SAB Member shall be considered "to have suffered a
"Disability" if: (i) he is incapacitated or disabled by accident, sickness or
otherwise so as to render him mentally or physically incapable of performing a
substantial part of the Services, with or without reasonable accommodation,
required to be performed by him under this Agreement for a period of at least 90
consecutive days, or for 90 days (whether or not consecutive) during any six (6)
month period. A termination by death or Disability shall not be considered a
termination for Cause.

            (E)   TERMINATION PURSUANT TO SECTION 4. Either party may terminate
this Agreement at any time subject to and in accordance with the provisions of
Section 4.

            (F)   SURVIVAL OF CERTAIN PROVISIONS. No termination of this
Agreement shall relieve the SAB Member or the Companies of any obligations
hereunder which by their terms are intended to survive the termination of the
SAB Member's association with the Companies, including, but not limited to, the
obligations of Sections 3 (as to only those provisions that are specifically
described as being applicable after the Term), 8, 9, 10, 11, 12, 15, 19, 20, 22
through 25 and 27 hereof.

            (G)   RETURN OF COMPANY PROPERTY. Upon termination of this Agreement
for any reason, the SAB Member shall promptly deliver to the Companies any and
all property of the Companies or their customers, licensees, licensors, or
affiliates which may be in his possession or control, including without
limitation, products, cell lines, materials, memoranda, notes, diskettes,
records, reports, laboratory notebooks, or other documents or photocopies of the
same and shall destroy any Confidential Information (as defined in Section 9
hereof) in intangible form.

      7.    INDEPENDENT CONTRACTOR. It is understood and agreed that the SAB
Member is an independent contractor and that neither this Agreement nor the
Services to be rendered hereunder shall for any purpose whatsoever or in any way
or manner create any employer-employee relationship between the parties. The SAB
Member shall not be entitled to any fringe benefits generally provided to
employees of either of the Companies and the Companies shall not be required to
maintain workers' compensation coverage for the SAB Member.

      8.    INVENTIONS. The SAB Member shall promptly disclose to the Companies,
and hereby assigns and agrees to assign to the Companies (or as otherwise
directed by the Companies), his full right, title and interest, if any, to all
Inventions (as defined below). The SAB Member agrees to cooperate fully with the
Companies, their attorneys and agents, in the preparation and filing of all
papers and other documents as may be required to perfect the Companies' rights
in and to any of such Inventions, including, but not limited to, execution of
any and all applications for domestic and foreign patents, copyrights or other
proprietary rights and the performance of such other acts (including, among
others, the execution and delivery of instruments of further assurance or
confirmation) requested by the Companies to assign the Inventions to the
Companies and to permit the Companies to file, obtain and enforce any patents,
copyrights or other proprietary rights in the Inventions, all at the Companies'
sole cost and expense. The SAB Member hereby designates the Companies as his
agent, and grants to the Companies a power of attorney with full power of
substitution, which power of attorney shall be deemed coupled with an interest,
for the purpose of effecting any such assignment hereunder

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from the SAB Member to the Companies. "Inventions" shall mean, for purposes of
this paragraph, ideas, discoveries, creations, manuscripts and properties,
innovations, improvements, know-how, inventions, trade secrets, apparatus,
developments, techniques, methods, biological processes, cell lines, laboratory
notebooks and formulas (whether or not patentable or copyrightable or
constituting trade secrets) conceived, made or discovered by the SAB Member
(whether alone or with others) within the Field as a result of consulting with
either of the Companies under this Agreement and/or as a result of Confidential
Information (as defined in Section 9 hereof) received from either of the
Companies.

      The Companies acknowledge and agree that the SAB Member is bound by the
UMass Provisions. In the event of any inconsistency between the terms and
provisions of this Section 8 and the UMass Provisions, the UMass Provisions
shall govern. In this respect, in no event shall the SAB Member's obligations
hereunder relate to any right, title or interest that the SAB Member may have in
ideas, discoveries, creations, manuscripts and properties, innovations,
improvements, know-how, inventions, trade secrets, apparatus, developments,
techniques, methods, biological processes, cell lines, laboratory notebooks and
formulas (whether or not patentable or copyrightable or constituting trade
secrets) conceived, made or discovered by the SAB Member (whether alone or with
others) with the use of facilities or fundings of any Affiliated Institution and
that the SAB Member is required to assign to his Affiliated Institution pursuant
to the rules and regulations of such Affiliated Institution. The SAB Member
agrees to not knowingly use or incorporate any third party proprietary
information into any Inventions or to disclose such information to the
Companies. Upon termination of this Agreement with the Companies, the SAB Member
shall provide to the Companies in writing a full, signed statement of all
Inventions in which the SAB Member participated prior to termination of this
Agreement.

      The SAB Member agrees to cooperate to facilitate any efforts by the
Companies to acquire by assignment or exclusive license rights to the existing
inventions, technologies and other intellectual property in the Field that have
been developed or identified by the SAB Member and his laboratory prior to or
during the Term. The SAB Member shall not be in breach of this Agreement if,
despite such cooperation, the Companies fail to consummate the foregoing.

      9.    CONFIDENTIALITY. During the Term, the SAB Member will be exposed to
certain information concerning the respective Companies' research, business,
Inventions, products, proposed new products, designs, clinical testing programs,
manufacturing processes and techniques, customers, and other information and
materials that embody trade secrets or technical or business information that is
confidential and proprietary to the Companies and is not generally known to the
public (collectively, "Confidential Information"). Confidential Information
shall not include information that (i) is in the public domain on the Effective
Date of this Agreement, (ii) is or was disclosed to the SAB Member by a third
party having no fiduciary relationship with the Companies and having no known
obligation of confidentiality with respect to such information, (iii) is or was
independently known or developed by the SAB Member without reference to the
Confidential Information as reasonably demonstrated by the SAB Member by written
records or (iv) is required by law or in a legal proceeding to be disclosed,
provided that the SAB Member shall give the Companies prior written notice of
such proposed disclosure so that the Companies may take such legal steps as they
deem appropriate to protect the Confidential Information. The SAB Member hereby
agrees, for a period of seven years following his receipt of such Confidential
Information, not to disclose or make use of, or allow

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others to use, any Confidential Information, except to the Companies' employees
and representatives, without the Companies' prior written consent, unless such
information becomes publicly available through no fault of the SAB Member;
provided, however, that such obligations of the SAB Member shall expire after
five years from the termination or expiration of this Agreement. In addition,
the SAB Member further agrees not to make any notes or memoranda relating to the
Business of the Companies other than for the benefit of the Companies and not to
use or permit to be used at any time any such notes or memoranda other than for
the benefit of the Companies.

      10.   INJUNCTIVE RELIEF. The SAB Member agrees that any breach of this
Agreement by him could cause irreparable damage to the Companies and that in the
event of such breach the Companies shall have the right to obtain injunctive
relief, including, without limitation, specific performance or other equitable
relief to prevent the violation of his obligations hereunder. It is expressly
understood and agreed that nothing herein contained shall be construed as
prohibiting the Companies from pursuing any other remedies available for such
breach or threatened breach, including, without limitation, the recovery of
damages by the Companies.

      11.   NO ASSIGNMENT BY THE SAB MEMBER. The Services to be rendered by the
SAB Member are personal in nature. The SAB Member may not assign or transfer
this Agreement or any of his rights or obligations hereunder. In no event shall
the SAB Member assign or delegate responsibility for actual performance of the
Services to any other natural person.

      12.   PUBLICATIONS. The SAB Member agrees that he will not at any time
during the time limitations set forth in paragraph 9 hereof, publish any
Confidential Information that becomes known to him as a result of his
relationship with the Companies which is, or pursuant to the terms hereof
becomes, the property of either of the Companies or any of its clients,
customers, consultants, licensors, licensees, or affiliates except to such
extent as may be necessary in the ordinary course of performing in good faith
his duties as a member of the SAB of either of the Companies and with the prior
written consent of the Companies.

      During the Term and for a period of two years thereafter, the SAB Member
agrees to submit to the Companies for a period of at least 30 days (the "Review
Period") a copy of any proposed manuscript or other materials to be published or
otherwise publicly disclosed by the SAB Member (each a "Proposed Publication")
which contains information derived, in whole or in part, from Services performed
for the Companies in sufficient time to enable the Companies to determine if
patentable Inventions or Confidential Information would be disclosed. Nothing
herein shall be construed to restrict the SAB Member's right to publish material
which does not contain Confidential Information. Following the expiration of the
Review Period, if the Companies do not notify the SAB Member that the Proposed
Publication discloses patentable Inventions or Confidential Information such
Proposed Publication shall be deemed to be approved by the Companies for
publication. In addition, the SAB Member will cooperate with the Companies in
this respect and will delete from the manuscript or other disclosure any
Confidential Information if requested by the Companies and will assist the
Companies in filing for patent protection for any patentable Inventions prior to
publication or other disclosure.

      13.   NO CONFLICTING AGREEMENTS. The SAB Member represents and warrants,
that he is not a party to any commitments or obligations that conflict with this
Agreement. In this

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regard, as a condition to the effectiveness of this Agreement the SAB Member
shall obtain the Principal Institution's execution of Exhibit A to this
Agreement. During the Term, the SAB Member will not enter into any agreement
either written or oral in conflict with this Agreement and will arrange to
provide Services under this Agreement in such a manner and at times that such
Services will not conflict with his responsibilities under any other agreement,
arrangement or understanding or pursuant to any employment relationship he has
at any time with any third party. In the event of any inconsistency between this
Agreement and any agreement or policy of any Affiliated Institution, the
agreement or policy of the Affiliated Institution shall control.

      14.   OTHER CONSULTING SERVICES. The Companies agree that SAB Member may
serve as a member of scientific advisory boards or in a similar capacity with,
and provide consulting services to, other companies in scientific areas outside
of the Field, provided that such service does not conflict or materially
interfere with his Services hereunder. The SAB Member shall notify the Companies
in writing in advance of such service, provided that the Companies shall hold
all such information in confidence, and provided further that the SAB Member
need not provide copies of any agreements with such other companies or any
information relating to his compensation for such services.

      15.   NONSOLICITATION. During the Term and for a period of one year
thereafter, the SAB Member, personally, will not, without the Companies' prior
written consent, directly solicit the employment of any employee of the
Companies or their affiliates with whom the SAB Member has had contact in
connection with the relationship arising under this Agreement. Nothing in this
Section 15 shall be deemed to prohibit general solicitations of employment by
any Affiliated Institution.

      16.   DISCLOSURE OF RELATIONSHIP. The parties each shall be entitled to
disclose that the SAB Member is serving on the SAB, including in any business
plan, press release, advertisement, prospectus or other offering document of
either of the Companies or their affiliates; provided that SAB Member shall have
the opportunity to review and approve press releases relating to announcement of
this Agreement and developments in the business of the respective Companies
prior to release, with approval of such press releases not to be unreasonably
delayed or withheld. Notwithstanding the foregoing, the Companies shall not
require the approval by the SAB Member of any press release or governmental
filing that in the opinion of the respective Companies' counsel is required to
be made.

      17.   SPONSORED RESEARCH AGREEMENT. The Companies shall use their
reasonable and diligent efforts to enter into as soon as is practicable after
the Effective Date a sponsored research agreement in the Field with the
Principal Institution with at least a three-year term under which the Company's
direct and indirect costs and expenses associated with the research payable to
the Principal Institution by either CytRx or Araios will be at least $750,000
per year.

      18.   NOTICES. All notices and other communications hereunder shall be
delivered or sent by facsimile transmission, recognized courier service,
registered or certified mail, return receipt requested. Any notice or required
submission of documents to CytRx made under the provisions of this Agreement
shall be deemed to have been constructively delivered to Araios for purposes of
this Agreement.

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            If to CytRx:

            Steven A. Kriegsman
            Chief Executive Officer
            CytRx Corporation
            11726 San Vicente Boulevard, Suite 650
            Los Angeles, CA 90049
            Fax: (310) 826-6139

            If to Araios:

            Mark A. Tepper, Ph.D.
            President
            Araios, Inc.
            One Innovation Drive
            Worcester, MA 01605
            Fax: (508) 767-3862

            with a copy to:

            General Counsel
            CytRx Corporation
            11726 San Vicente Boulevard, Suite 650
            Los Angeles, CA 90049
            Fax: (310) 826-6139

            If to the SAB Member:

            Tariq M. Rana, Ph.D.
            Professor and Director of Chemical Biology Program
            Department of Biochemistry and Molecular Pharmacology
            University of Massachusetts Medical School
            364 Plantation Street, LRB room 828,
            Worcester, MA 01605-2324
            Fax: (508) 856-8015

      Such notice or communication shall be deemed to have been given as of the
date sent by the facsimile or delivered to a recognized courier service, or
three days following the date sent by registered or certified mail.

      19.   SUCCESSORS AND ASSIGNS. This Agreement shall be binding upon and
inure to the benefit of the parties and their respective legal representatives,
successors and permitted assigns. The SAB Member agrees that either of the
Companies may assign this Agreement, in whole but not in part, to any purchaser
of all or substantially all of its assets or to any successor corporation
resulting from any merger, consolidation or other reorganization of either of
the Companies with or into such corporations (including without limitation a
merger of Araios into CytRx or other acquisition by CytRx of all of the assets
of Araios). Each of the Companies also may assign this

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Agreement, in whole but not in part, to any person or entity controlled by, in
control of, or under common control with, the respective Companies, if it
obtains the prior written consent of the SAB Member, which consent shall not
unreasonably be withheld or delayed and which shall not be required in the case
of CytRx's acquisition of Araios by merger or otherwise; provided, however, that
no such assignment shall relieve either of the Companies of its liability to the
SAB Member hereunder. The Companies may not otherwise assign this Agreement
without the SAB Member's prior written consent.

      20.   INDEMNIFICATION. The Companies shall jointly and severally
indemnify, defend and hold harmless the SAB Member from any claim, loss,
liability or expense (including reasonable attorney's fees) incurred by him as a
result of the performance of his Services hereunder in accordance with the terms
hereof, a material breach by either of the Companies hereof or any gross
negligence or willful misconduct by either of the Companies or their respective
officers or directors in connection with this Agreement or otherwise relating to
or resulting from the performance of the Services hereunder, except where such
claim, loss, liability or expense is attributable primarily to the SAB Member's
own gross negligence or willful misconduct.

      21.   ENTIRE AGREEMENT; COUNTERPARTS. This Agreement constitutes the
entire agreement among the parties as to the subject matter hereof. No provision
of this Agreement shall be waived, altered or cancelled except in writing signed
by the party against whom such waiver, alteration or cancellation is asserted.
Any such waiver shall be limited to the particular instance and the particular
time when and for which it is given. This Agreement may be executed in one or
more counterparts, and by different parties hereto on separate counterparts,
each of which shall be deemed an original, but all of which together shall
constitute one and the same instrument.

      22.   GOVERNING LAW. This Agreement shall be governed by and construed in
accordance with the internal laws of the State of Delaware, without regard to
conflict of law principles.

      23.   ENFORCEABILITY. The invalidity or unenforceability of any provision
hereof as to an obligation of a party shall in no way affect the validity or
enforceability of any other provision of this Agreement, provided that if such
invalidity or unenforceability materially adversely affects the benefits the
other party reasonably expected to receive hereunder, that party shall have the
right to terminate this Agreement. Moreover, if one or more of the provisions
contained in this Agreement shall for any reason be held to be excessively broad
as to scope, activity or subject so as to be unenforceable at law, such
provision or provisions shall be construed by limiting or reducing it or them,
so as to be enforceable to the extent compatible with the applicable law as it
shall then appear.

      24.   CONSTRUCTION. This Agreement has been prepared jointly and shall not
be strictly construed against any party.

      25.   RESOLUTION OF DISPUTES. Any dispute arising under or in connection
with any matter related to this Agreement or any related agreement shall be
resolved exclusively by arbitration. The arbitration will be in conformity with
and subject to the applicable rules and

                                       11
<PAGE>

procedures of the American Arbitration Association. All parties agree to be (i)
subject to the jurisdiction and venue of the arbitration in Los Angeles,
California; and (ii) bound by the decision of the arbitrator as the final
decision with respect to the dispute.

      26.   ADVICE OF COUNSEL. Each party acknowledges that, in executing this
Agreement, such party has had the opportunity to seek the advice of independent
legal counsel, and has read and understood all of the terms and provisions of
this Agreement.

      27.   FEES AND EXPENSES. Upon request by the SAB Member and presentation
of invoices therefor in such detail as the Companies shall reasonably request,
the Companies shall pay or reimburse the SAB Member up to a total of $10,000 in
legal fees and disbursements incurred by him in connection with the negotiation
and preparation of this Agreement. Except as otherwise specifically provided in
this Agreement, the parties shall bear their own costs and expenses in
connection with this Agreement.

      IN WITNESS WHEREOF, the parties hereto have duly executed this Scientific
Advisory Board Agreement as a sealed instrument as the date first written above.

                                             CYTRX CORPORATION

                                             By:  /s/ Steven A. Kriegsman
                                                 -------------------------------
                                                   Steven A. Kriegsman
                                                   Chief Executive Officer

                                             ARAIOS, INC.

                                             By:  /s/ Mark A. Tepper
                                                 -------------------------------
                                                  Mark A. Tepper,  Ph.D.
                                                  President

SAB MEMBER

/s/ Tariz M. Rana
-------------------------------
Name:  Tariq M. Rana, Ph.D.

Social Security Number:

_______________________________

Effective Date:  March 3, 2004

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<PAGE>

                                   SCHEDULE A

                             CONFLICTING AGREEMENTS

            UNIVERSITY OF MASSACHUSETTS UNIFORM CONSULTING AGREEMENT
                                   PROVISIONS

All faculty at the University of Massachusetts (the "University") are subject to
the University Policy on Faculty Consulting and Outside Activities (the
`Policy"). The Policy recommends that faculty at the University attach these
Uniform Consulting Agreement Provisions ("Uniform Provisions") to any agreement
or arrangement ("Consulting Agreement") under which a faculty member will
provide consulting services to, or will engage in other non-academic activities
in his or her area of expertise on behalf of any for-profit organization (a
"Company"). These Uniform Provisions are intended to clarify, among other
things, the respective legal rights of the University and the Company in any
intellectual property and other work product that may be developed or discovered
by the faculty member in the course of performing services for the Company. If
any term of the Uniform Provisions is inconsistent with a term of the Consulting
Agreement to which the Uniform Provisions are attached, the terms of the Uniform
Provisions govern.

University faculty are permitted to devote the equivalent of one day within the
academic week to the performance of outside activities, including consulting
with Companies. These activities must be reported to the Department Chair of the
faculty member in order to ensure compliance with this time restriction and the
ability of the faculty member to meet his or her responsibilities to the
University. In certain instances, these activities must also be reviewed by the
University's Conflicts Committee. The Conflicts Committee may impose
restrictions on the consulting relationship.

University faculty are ordinarily prohibited from using University-administered
funds, facilities, and equipment in the performance of services for a Company
pursuant to a Consulting Agreement. In addition, faculty must obtain special
approval to involve University students in consulting or other services for
Companies. Companies may obtain access to University facilities, equipment, and
personnel under a sponsored research agreement with the University.

University faculty may not use the name of the University in relation to any
outside activities, including consulting work, except to describe their
credentials.

University faculty are permitted to assign to a Company their rights in any
invention, discovery, or development (collectively, "Intellectual Property")
that arises while performing services under a Consulting Agreement, provided
that the faculty member did not use University-administered funds, facilities,
or equipment (collectively, "University Resources") in the course of developing
that Intellectual Property. If a faculty member made significant use of
University Resources, the faculty member is contractually obligated to assign to
the University all of his or her rights in that Intellectual Property.

                                       A-1
<PAGE>

The University presumes that a faculty member did make significant use of
University Resources in the development of Intellectual Property that is the
same as, directly related to, or substantially similar to a research project in
which that faculty member is engaged at the University. In order to avoid any
confusion regarding ownership of Intellectual Property, the University has
determined and Company agrees that the field of services to be provided under
this Consulting Agreement is directly related to or substantially similar to the
research projects undertaken by the faculty member at the University. Therefore,
any Intellectual Property developed by the faculty member during the term of
this Consulting Agreement is owned by the University, and the Company may enter
into negotiations to obtain license rights to the Intellectual Property.

No Consulting Agreement may limit the ability of a University faculty member to
use or publish information that (a) was developed, discovered, or acquired by
the faculty member in the course of research performed at the University or
otherwise outside the scope of the consulting services, (b) was in the public
domain before the consulting services were performed (c) entered the public
domain by means other than an unauthorized disclosure resulting from an act or
omission by the faculty member, (d) was known to the faculty member or the
University before the consulting services were performed, or (e) is required to
be disclosed in order to comply with applicable law, regulations, or a court
order.

A Company may require a faculty member to leave with the Company any notes,
data, and records developed in the performance of consulting services, provided
that the faculty member may retain one copy of those documents for archival
purposes.

Companies should be aware that, in addition to the Policy, University faculty
are subject to the University Intellectual Property Policy and the University
Policy on Conflicts of Interest Relating to Intellectual Property and Commercial
Ventures. The University will make the three policies available upon request.

                                      A-2
<PAGE>

These Uniform Provisions remain in effect during the entire term of the
Consulting Agreement to which they are attached.

AGREED AND ACCEPTED:

FACULTY MEMBER                                 CYTRX CORPORATION

By: /s/ Tariq M. Rana                          By: /s/ Steven A. Kriegsman
    ---------------------------                   ------------------------------
Printed Name: Tariq M. Rana                    Printed Name: Steven A. Kriegsman

Date:  Jan. 20, 2004                           Title: Chief Executive Officer

                                               Date:____________________________

UNIVERSITY OF MASSACHUSETTS                    ARAIOS, INC.

By: /s/ Chester A. Bisbee                      By: /s/ Mark A. Tepper
    ---------------------------                   ------------------------------
Printed Name: Chester A. Bisbee, Ph.D., J.D.   Printed Name: Mark A. Tepper

Title: Acting Director, Office of Technology   Title: President
         Management

                                               Date:____________________________
Date: 4-9-04

                                      A-3