<PAGE>
                                                                   EXHIBIT 10.75


                 MUTUAL GENERAL RELEASE AND SEVERANCE AGREEMENT

            This Mutual General Release and Severance Agreement (the
"Agreement") is entered into by and between CytRx Corporation, a Delaware
Corporation (the "Company") and Gregory R. Liberman ("Liberman") as of the date
on which Liberman executes and dates this Agreement. The Company and Liberman
are referred to collectively as the "Parties."

                                    RECITALS

            A.    Whereas, Liberman has been employed by the Company, as its
General Counsel and Corporate Secretary, since January 12, 2004 pursuant to an
employment agreement of that same date (the "Employment Agreement"); and

            B.    Whereas, Liberman has alleged that he has suffered a
constructive discharge in violation of his Employment Agreement and other
rights; and

            C.    Whereas, the Company denies that it constructively discharged
Liberman or otherwise violated his rights; and

            D.    Whereas, the Parties wish to avoid the time, expense,
inconvenience, publicity, risks, and costs involved in litigation of Liberman's
threatened claims, and on the terms set forth below, the Parties desire to
extinguish the Employment Agreement and compromise and settle all disputes
between them, including, but not limited to, all claims arising out of or
relating to Liberman's employment with the Company or the termination of that
employment.

            NOW, therefore, in consideration of the foregoing stipulated facts,
and the mutual promises, agreements and understandings contained herein, the
Parties hereby agree as follows:

            1.    Settlement Consideration

            Subject to the terms and conditions set forth below, the Company
shall provide the following payments and compensation:

                  a.    The Company will pay Liberman fifty-eight thousand three
hundred thirty-four dollars ($58,334) (equal to four (4) months salary), with
the Company to withhold appropriate taxes, by cashier's check delivered to
Liberman concurrent with his delivery of this executed Agreement.

                  b.    The Company will pay Liberman twenty-nine thousand one
hundred sixty-seven dollars ($29,167) (equal to an additional two (2) months of
salary), with the Company to withhold appropriate taxes, by cashier's check
delivered to Liberman on May 14, 2004 (the "Severance Date").


                                       1
<PAGE>
                  c.    Within two (2) business days from the date Liberman
delivers this executed Agreement, the Company will deposit into escrow, for
Liberman's benefit, with an escrow holder reasonably acceptable to the Parties,
the gross sum of fifty-eight thousand three hundred thirty-four dollars
($58,334) (equal to an additional four (4) months of salary). Beginning with the
first day of the 6th month after the Severance Date, and also beginning with the
first day of each subsequent month through the 9th month after the Severance
Date, with each such month calculated as 30-day periods following the Severance
Date, Liberman may draw from the escrow account up to fourteen-thousand five
hundred eighty-three dollars ($14,583), depending upon his earnings for the
previous month. To effect a withdrawal, Liberman shall present to the escrow
officer an affidavit regarding his employment and consulting income, if any,
from the month preceding the date on which he draws from the escrow account. At
such time as the affidavit is presented to the escrow officer, the escrow
officer shall pay Liberman fourteen-thousand five hundred eighty-three dollars
($14,583) minus income Liberman earned from employment and consulting during the
previous month. After the 8th month after the Severance Date, and once Liberman
has been paid any amount to which he is entitled under this Agreement, any
amount remaining in escrow shall be returned to the Company. The Company agrees
to pay all fees and costs of the escrow and to cause to be created an escrow
account consistent with this Agreement and take all other steps to effect the
intent of this paragraph.

                  d.    The Company will pay for up to twelve (12) months of
COBRA insurance coverage for Liberman, commencing on the Severance Date and
ending on the first anniversary of the Severance Date. The Company's obligation
to provide such coverage will cease on the date Liberman obtains comparable
coverage from another full-time employer. Liberman shall provide the Company
with notice that he has obtained comparable coverage promptly, but not later
than three business days after he obtains such coverage. If Liberman is
self-employed during the time the Company is required to provide COBRA insurance
coverage, the Company shall continue to provide COBRA insurance coverage until
twelve (12) months from the Severance Date. In the event the Company's COBRA
policy is cancelled for any reason whatsoever during the period in which
Liberman is to receive such COBRA coverage, the Company will obtain and pay for
comparable insurance coverage from an alternative reputable insurance provider
(such as Aetna, Blue Cross or Travelers, by way of examples).

                  e.    Effective immediately, the Company shall vest options to
purchase 87,500 shares of the Company's common stock, which the Company granted
Liberman in connection with the commencement of his employment with the Company.
Liberman will have 10 years from the date such options were granted within which
to exercise such options, on either a cash or cashless basis.

                  f.    The Company will pay Liberman's counsel, Alschuler
Grossman Stein & Kahan LLP ("AGS&K"), the sum of five thousand dollars ($5,000),
which the Company shall pay by cashier's check exchanged concurrent with
Liberman's delivery of this signed Agreement. The Company shall issue a Tax Form
1099 only to AGS&K for this amount.

                  g.    At the time this Agreement is executed, the Company
shall pay Liberman a cashier's check for the gross sum of five thousand eight
hundred thirty-three dollars ($5,833), less appropriate withholding taxes, which
constitutes payment in full for unused vacation to which he is entitled.


                                       2
<PAGE>
            2.    General Release by Mr. Liberman

            Except for the obligations set forth in this Agreement and those
claims expressly reserved hereby, Liberman on behalf of himself, his attorneys
and agents, hereby releases, acquits and forever discharges the Company and all
of its current or former shareholders, officers, directors, agents, attorneys,
employees, representatives, predecessors-in-interest, successors and assigns,
and all individuals or entities acting by, through, under or in concert with any
of them (collectively, the "Released Company Parties"), from any and all
charges, controversies, claims, wages, rights, agreements, actions, costs or
expenses, causes of action, obligations, damages, losses, promises and
liabilities of whatever kind or nature (such as claims for emotional distress,
wages and attorneys' fees), in law or equity or otherwise, whether known or
unknown, suspected or unsuspected, from the beginning of time to the date he
signs this Agreement, provided, however, that nothing in this Agreement or
provision shall be deemed a release of the following claims: (a) claims for
defense and indemnification to which Liberman may be entitled pursuant to common
or statutory law, including but not limited to Labor Code Section 2802 or
Corporations Code Section 317, by virtue of his role as an employee or officer
of the Company; (b) claims for outstanding, unpaid medical expenses submitted to
the Company's medical insurance plan; (c) claims for amounts to be paid and
stock options awarded pursuant to this Agreement; and (d) claims to enforce this
Agreement.

            Liberman expressly agrees that, other than those claims expressly
reserved herein, this Agreement and General Release extends to all claims of
every nature and kind, known or unknown, suspected or unsuspected, vested or
contingent, past, present or future, arising from or attributable to any alleged
act or omission of the Released Parties or their respective agents or
representatives, occurring prior to the execution of this Agreement, including,
without limitation, claims arising from the employment by, or the termination of
Liberman's employment with, any of the Released Parties.

            3.    General Release by the Company

            Except for the obligations set forth in this Agreement, the Company,
on behalf of itself, its attorneys, its officers, directors and agents, acquits
and forever discharges Liberman and his representatives, agents and assigns
(collectively, the "Released Liberman Parties"), from any and all charges,
controversies, claims, wages, rights, agreements, actions, costs or expenses,
causes of action, obligations, damages, losses, promises and liabilities of
whatever kind or nature (such as claims for attorneys' fees), in law or equity
or otherwise, whether known or unknown, suspected or unsuspected, from the
beginning of time to the date it signs this Agreement, provided, however, that
nothing in this Agreement or provision shall be deemed a release of the
following claims: (a) claims for defense and indemnification to which the
Company may be entitled pursuant to common or statutory law by reason of its
role as Liberman's employer; and (b) claims to enforce this Agreement.

            The Company, its attorneys, officers, directors, and agents
expressly agree that this Agreement and General Release extends to all claims of
every nature and kind, known or unknown, suspected or unsuspected, vested or
contingent, past, present or future, arising from or attributable to any alleged
act or omission of Liberman occurring prior to the execution of this


                                       3
<PAGE>
Agreement (except for representations and warranties and other obligations
created by this Agreement), including, without limitation, claims arising from
Liberman's employment.

            4.    Civil Code Section 1542 Waiver

            The Parties are aware of and have been advised by counsel of
California Civil Code Section 1542, which provides as follows:

            "A GENERAL RELEASE DOES NOT EXTEND TO CLAIMS WHICH THE CREDITOR DOES
NOT KNOW OR SUSPECT TO EXIST IN HER FAVOR AT THE TIME OF EXECUTING THE RELEASE,
WHICH IF KNOWN BY HIM MUST HAVE MATERIALLY AFFECTED HER SETTLEMENT WITH THE
DEBTOR."

            With full awareness and understanding of this provision, as to the
claims released by this Agreement, the Parties hereby waive all rights, that
this provision or any comparable provision under any state or federal law may
give to them. They intend the mutual general releases set forth in this
Agreement to apply to claims which they do not presently know to exist at this
time. They understand that the facts with respect to which this Agreement is
given may hereafter prove to be different from the facts now known or believed
by them (other than as to representations and warranties contained herein), and
they hereby accept and assume the risk thereof and agree that this Agreement
shall be and shall remain, in all respects, effective and not subject to
termination or rescission by reason of any such difference in facts.

            5.    Representation and Warranty of No Fraud

            By signing this Agreement, in exchange for the Company's release of
unknown claims by waiving Civil Code section 1542 in Paragraph 4 above, Liberman
represents and warrants that during his employment with the Company, he did not
engage in fraud or other intentionally unlawful conduct relating in any way to,
or arising from or in connection with, his employment with the Company. The
Company represents and warrants that it is not aware of any fraud or other
intentionally unlawful conduct by Liberman with respect to performance of his
duties for the Company.

            6.    Supplemental Mutual General Releases With Civil Code Section
                  1542 Waivers

            As a material portion of the consideration for the Parties' releases
herein, the Parties each agree that they will each execute supplemental mutual
general releases and 1542 waivers in favor of each other, in the form of Exhibit
A hereto, within one (1) business day after Liberman's Severance Date and,
again, at the conclusion of the consulting period in Paragraph 9 below.

            7.    Resignation/Limited Duties/Indemnity

            Provided the Company has signed this Agreement and has delivered all
settlement compensation provided for in Paragraph 1, above, in accordance with
this Agreement, Liberman shall resign his employment with the Company effective
the Severance Date.


                                       4
<PAGE>
            Even after Liberman's employment has ended, the Company agrees that
it will continue to defend and indemnify Liberman as set forth under the
Company's Certificate or Articles of Incorporation and Bylaws in effect as of
January 12, 2004, against any and all claims, cause of action, inquiries,
audits, administrative or other proceedings, whether private, governmental or
otherwise, relating to or arising from his employment with the Company, or his
role as a corporate officer. The Company shall continue to insure Liberman as an
additional insured under its current policy of directors and officers liability
insurance, or under any replacements policies in effect, for events occurring
while the Company employed Liberman. Until the Severance Date, the Company shall
continue to be required to provide employed lawyers professional liability
insurance ("ELP"), or its equivalent, for the benefit of Liberman and shall
insure Liberman thereunder.

            8.    Mutual Non-Disparagement/References

            Liberman agrees that he will not, either directly or indirectly,
disparage or otherwise make negative remarks regarding the Company or its
then-current officers or directors, or its products or its potential products.
The Company agrees that it will not, either directly or indirectly, disparage or
otherwise make negative remarks regarding or relating to Liberman. In the event
that the Company's Human Resources Department receives inquiries about
Liberman's employment, it will not make disparaging remarks but will confirm
only the length of his employment, positions held and his annual salary as of
the date of his departure from the Company. Additionally, the Company's Board of
Directors and other officers will be instructed not to make disparaging remarks,
directly or indirectly, about Liberman, and their failure to comply shall be
deemed a breach of this Agreement by the Company. Employees shall be advised to
refer all inquires about Liberman to the Human Resources Department. Liberman's
failure to comply with the provisions of this Section shall be deemed a breach
of this Agreement by Liberman.

            The Company will provide Liberman with letters of reference in a
form acceptable to Liberman, which form is attached hereto as Exhibit B.

            Nothing in this Agreement shall prohibit the Parties from testifying
truthfully under oath, from responding truthfully to discovery responses and
subpoenas in any legal proceeding, from prosecuting legal action as a plaintiff
or defendant, from responding truthfully to inquiries from any government or
listing entity or agency, or from responding truthfully to inquiries from the
Company or its directors, officers or authorized agents.

            9.    Limited Consulting Relationship

            Subject to his other personal and professional commitments, Liberman
agrees to make himself reasonably available for thirty (30) days following the
Severance Date, up to a maximum of 20 hours per week, at an hourly rate of $100,
paid weekly, to assist the Company in transitioning Liberman's responsibilities
to other counsel, whether in-house counsel or outside counsel. The Company also
will reimburse Liberman for any travel and other expenses he incurs in
connection with this consulting relationship. Liberman shall not be required to
practice law while consulting for the Company unless the Company provides
professional liability insurance obtained on Liberman's behalf and insures him
thereunder. Amounts earned by Liberman in this


                                       5
<PAGE>
consulting relationship shall not be deducted from any other amounts to which
Liberman is entitled under this Agreement.

            10.   Confidentiality of Trade Secrets

            Except as required by law, for a period of five (5) years from the
execution of this Agreement, Liberman shall hold and keep secret and
confidential all "trade secrets" (within the meaning of applicable law) and
other confidential or proprietary information of the Company (collectively, such
trade secrets and other confidential or proprietary information of the Company
shall be referred to herein as "Confidential Information") provided, however,
that with respect to trade secrets, Liberman shall hold and keep secret and
confidential such trade secrets for as long as they remain trade secrets under
applicable law. Confidential Information does not include (a) information which
is now or hereafter becomes publicly known or available through no act or
failure on the part of Liberman, (b) information which is hereafter furnished to
Liberman by a third party, the disclosure of which does not constitute a
violation of an obligation by such third party to the Company and (c)
information which is independently developed or known by Liberman, without use
or reference to the Confidential Information.

            11.   Non-Solicitation

            For a period of one (1) year from the date of execution of this
Agreement, Liberman agrees not to induce any current employee of the Company at
the date of execution of this Agreement to terminate his or her employment with
the Company or solicit to hire any such person. Liberman shall not be prohibited
from soliciting to hire a former employee of the Company who has terminated his
or her employment with the Company independent of inducement by Liberman to do
so.

            12.   Arbitration

            The parties agree that if any controversy or claim shall arise out
of this Agreement or the breach hereof (other than claims (a) for equitable
relief, including specific performance, injunctive relief or temporary
restraining orders or (b) enforcing this Paragraph 10 or an arbitration award
granted in accordance herewith), and either party shall request that the matter
be settled by arbitration, the matter shall be settled exclusively by final and
binding arbitration before JAMS (or its successor pursuant to the United States
Arbitration Act, 9 U.S.C. Section 1 et seq.) in accordance with the provisions
of JAMS' Streamlined Arbitration Rules and Procedures in effect at such time, by
a single arbitrator, if the parties shall agree upon one, or by one
arbitrator-appointee designated by JAMS. All arbitration proceedings shall be
held in the City of Los Angeles, and each party agrees to comply in all respects
with any award made in such proceeding and to the entry of a judgment in any
jurisdiction upon any award rendered in such proceeding. All costs and expenses
of arbitration shall be borne by the Company. The losing party in such
arbitration, or as otherwise directed by the arbitrator or arbitrators, shall
pay the prevailing party's reasonable attorneys' fees incurred in connection
therewith.

            13.   Benitec

                  a.    Liberman agrees that for a period of two years from the
date he executes this Agreement, he will not accept employment or consult with
Benitec Ltd.


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<PAGE>
("Benitec"), or any entity at least 50% of which Benitec owns, including owned
through a Benitec subsidiary. If Benitec acquires a 50% or greater interest in a
company for which Liberman is already employed, he may continue his employment
with such company, provided Liberman is not aware that such company was
established with a plan to be owned 50% or more by Benitec.

                  b.    Liberman acknowledges and agrees that his breach of this
provision regarding Benitec may cause the Company great or irreparable injury,
that it may be extremely difficult to ascertain the amount of compensation which
would afford the Company adequate relief from such a breach, that pecuniary
compensation alone would not afford adequate relief, and that in the event
Liberman commits such a breach of this provision, the Company will be entitled
to seek the remedy of injunctive relief, in addition to any and all other legal
or equitable remedies, to restrain and enjoin him from being employed by or
consulting for Benitec or any company of which Benitec owns at least 50%.

            14.   Additional Representations and Obligations

                  a.    The Parties represent and warrant that they have not
assigned or in any way conveyed, transferred or encumbered all or any portion of
the claims released or rights covered by this Agreement.

                  b.    Liberman represents and warrants that he participated in
the preparation of the Company's Form 10-K for the 2003 fiscal year and he is
not aware of any material misstatements or omissions in the current version of
the document.

                  c.    Liberman represents and warrants that he or others have
disclosed to the Company's Governance or Audit Committee all material areas of
conduct, of which Liberman is aware, engaged in by the Company or its officers,
directors or employees, that Liberman believes are relevant to the Company's
Governance and Audit Committee investigations of the propriety of Company
conduct. This representation and warranty does not include Liberman's
contentions regarding his constructive discharge, which the Company denies, and
which are among the claims released herein.

                  d.    The Parties represent and warrant that they have not
filed or requested to be filed or initiated any administrative charges or claims
or legal actions against any of the Released Company Parties or Released
Liberman Parties, including without limitation any state or federal court
actions, any workers' compensation or disability claims or any equal employment
opportunity complaint.

                  e.    The Parties agree and promise that they will not file
any charge, claim, suit, or action to pursue any claims released herein. If any
court of law or federal, state, or local administrative agency assumes
jurisdiction of any charge, claim, suit, or action on behalf of any of the
Parties based on the matters released herein, the Parties agree to direct that
court, board or agency to withdraw from, or to dismiss, the charge, claim, suit,
or action with prejudice.

                  f.    The Parties agree that if any of them commences, joins
in, or in any manner attempts to assert a claim released by this Agreement,
he/it shall pay to the other


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<PAGE>
Party or Released Party against whom such claim is released all costs and
expenses, including all attorneys' fees, which that Party or Released Party
incurs in defending against such a claim.

                  g.    The Company represents and warrants that the Board of
Directors has approved this Agreement, and that the individual executing this
Agreement on behalf of the Company is fully authorized and empowered to do so
and to bind the Company.

            15.   Miscellaneous Provisions

                  a.    This Agreement is entered into in settlement and
compromise of disputed claims between the Parties and does not constitute and
shall not be construed as an admission by any of the Parties of any liability or
of any fact or matter whatsoever.

                  b.    If any portion, provision or part of this Agreement is
held, determined or adjudicated to be invalid, unenforceable or void for any
reason, each such portion, provision or part shall be severed from the remaining
portions, provisions or parts of this Agreement and shall not affect the
validity or enforceability of such remaining portions, provisions or parts.

                  c.    This Agreement shall be binding upon and inure to the
benefit of the Parties and their respective heirs, legal representatives,
successors and assigns.

                  d.    This Agreement shall be construed under and enforced in
accordance with the substantive laws of the State of California.

                  e.    This Agreement sets forth the entire agreement among the
Parties and supersedes all prior oral or written agreements, negotiations,
discussions, or understandings concerning the subject matter hereof, including
but not limited to the Employment Agreement, except that the terms of the
Company's stock option plan and Liberman's stock option agreement, as amended in
accordance with the terms of this Agreement, shall govern disposition of the
stock options awarded to Liberman, except as expressly modified by this
Agreement. The terms of the escrow regarding payment to be made in Paragraph
1(c) shall govern the escrow as long as it is consistent with Paragraph 1(c).
The terms of this Agreement may not be altered, amended, waived or modified,
except by a further written agreement signed by all of the Parties.

                  f.    This Agreement may be executed in counterparts (and
exchanged via telecopier), each of which shall constitute an original, but all
of which shall constitute one and the same agreement, provided that each signing
party shall have received a copy of the signature page signed by the other
party.

                  g.    The Parties to this Agreement each cooperated in its
drafting and preparation. Thus, the language of all parts of this Agreement
shall in all cases be construed as a whole, according to its fair meaning and
not strictly for or against any party as the drafter thereof.

                  h.    Each party agrees to make, execute and deliver such
other instruments or documents, and to do or cause to be done such further or
additional acts, as


                                       8
<PAGE>
reasonably may be necessary in order to effectuate the purposes or to implement
the terms of this Agreement.

                  i.    No waiver of any breach of any term or provision of this
Agreement shall be construed to be, nor shall be, a waiver of any other breach
of this Agreement. No waiver shall be binding unless in writing and signed by
the party waiving the breach.

                  j.    Section headings in this Agreement are included for
convenience of reference only.

                  k.    Any notices, demands, request or other communications
that any party desires or is required to deliver to any other party pursuant to
this Agreement shall be in writing and shall be delivered in a sealed envelope
marked "Confidential - To Be Opened by Addressee Only" by hand delivery or
overnight delivery (through a nationally recognized courier, such as UPS or
Federal Express) to the addresses set forth below. Unless notice of a different
address has been given in accordance with this paragraph, all such notices shall
be addressed as follows:

            To the Company:           CytRx Corporation
                                      Steve Kriegsman, CEO
                                      11726 San Vicente Blvd., Suite 650
                                      Los Angeles, CA 90049


            To Liberman:              Gregory R. Liberman
                                      To the address in the Company's
                                      payroll records

            l.    If any action (including but not limited to any arbitration)
is brought to enforce or interpret any provision of this Agreement, or the
rights or obligations of any party hereunder, the prevailing party shall be
entitled to recover, as an element of such party's costs of suit, and not as
damages, all reasonable outside attorneys' fees and costs incurred or sustained
by such prevailing party in connection with such action, including, without
limitation, legal fees and costs. The "prevailing party" shall be defined as the
party who is entitled to recover his or its costs of suit.

            m.    The Parties hereto, and each of them, represent and declare
that in executing this Agreement, they rely solely upon their own judgments,
beliefs and knowledge, and on the advice and recommendations of their own
independently selected counsel, concerning the nature, extent and duration of
their rights and claims and that they have not been influenced to any extent
whatsoever in executing the same by any representations or statements covering
any matters made by any of the Parties hereto or by any person representing them
or any of them. The Parties acknowledge that no party hereto nor any of their
representatives has made any promise, representation or warranty whatsoever,
written or oral, as any inducement to enter into this Agreement, except as
expressly set forth in this Agreement.


                                       9
<PAGE>
            n.    The Parties, and each of them, further represent and warrant
that they have carefully read this Agreement and know and understand the
contents thereof, and that they signed this Agreement freely and voluntarily.

            o.    Each party to this Agreement has made such investigation of
the facts pertaining to this Agreement and of all matters pertaining thereto as
he, she or it deems necessary.

            p.    In entering into this Agreement, each party assumes the risk
of any misrepresentation, concealment or mistake. If any party should
subsequently discover that any fact relied upon by him, her or it, or that his,
her or its understanding of the facts or of the law was incorrect, such party
shall not be entitled to any relief in such connection or otherwise, including,
without limiting the generality of the foregoing, any alleged right or claim to
set aside or rescind this Agreement. This Agreement is intended to be and is
final and binding between the Parties hereto with respect to released claims,
regardless of any claims of misrepresentation, promise made without the
intention of performing, concealment of fact, mistake of fact or law, or of any
other circumstance whatsoever.

            q.    Except as provided in Paragraph 1(f), the Parties are each
solely responsible for their own attorneys' fees and costs incurred before, from
and after the date of this Agreement, and at all times thereafter, except as may
be awarded in connection with any proceedings arising regarding enforcement,
interpretation, implementation or modifiability of the Agreement.

            r.    The representations, warranties and covenants contained in
this Agreement are deemed to and shall survive the execution and delivery of
this Agreement by all of the Parties.

            s.    THE PARTIES REPRESENT AND WARRANT THAT THEY HAVE THOROUGHLY
READ AND CONSIDERED ALL ASPECTS OF THIS AGREEMENT, THAT THEY UNDERSTAND ALL
PROVISIONS OF THIS AGREEMENT, THAT THEY HAVE HAD THE OPPORTUNITY TO CONSULT WITH
COUNSEL THROUGHOUT THIS PROCESS AND THAT THEY ARE VOLUNTARILY ENTERING INTO THE
AGREEMENT OF THEIR OWN FREE WILL, WITHOUT DURESS OR COERCION OF ANY KIND.

Dated: May 12, 2004                GREGORY R. LIBERMAN, AN INDIVIDUAL


                                   /s/ Gregory R. Liberman
                                   ---------------------------------------------

Dated: May 12, 2004                CYTRX CORPORATION


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


                                       10
<PAGE>
                                   EXHIBIT A

    Supplemental Mutual General Releases and Civil Code Section 1542 Waivers

                  Supplemental General Release by Mr. Liberman

            Except for the obligations set forth in the Mutual General Release
and Severance Agreement executed by Liberman and the Company (the "Agreement")
and these supplemental general releases and Civil Code Section 1542 waivers (the
"Release"), and those claims expressly reserved thereby, Liberman on behalf of
himself, his attorneys and agents, hereby releases, acquits and forever
discharges the Company and all of its current or former shareholders, officers,
directors, agents, attorneys, employees, representatives,
predecessors-in-interest, successors and assigns, and all individuals or
entities acting by, through, under or in concert with any of them (collectively,
the "Released Company Parties"), from any and all charges, controversies,
claims, wages, rights, agreements, actions, costs or expenses, causes of action,
obligations, damages, losses, promises and liabilities of whatever kind or
nature (such as claims for emotional distress, wages and attorneys' fees), in
law or equity or otherwise, whether known or unknown, suspected or unsuspected,
from the beginning of time to the date he signs this Release, provided, however,
that nothing in this Release shall be deemed a release of the following claims:
(a) claims for defense and indemnification to which Liberman may be entitled
pursuant to common or statutory law, including but not limited to Labor Code
Section 2802 or Corporations Code Section 317, by virtue of his role as an
employee or officer of the Company; (b) claims for outstanding, unpaid medical
expenses submitted to the Company's medical insurance plan; (c) claims for
amounts to be paid and stock options awarded pursuant to this Agreement; and (d)
claims to enforce the Agreement or this Release.

            Liberman expressly agrees that, other than those claims expressly
reserved in the Agreement and this Release, this Release extends to all claims
of every nature and kind, known or unknown, suspected or unsuspected, vested or
contingent, past, present or future, arising from or attributable to any alleged
act or omission of the Released Parties or their respective agents or
representatives, occurring prior to the execution of this Release, including,
without limitation, claims arising from the employment by, or the termination of
Liberman's employment with, any of the Released Parties.

                  Supplemental General Release by the Company

            Except for the obligations set forth in the Agreement and this
Release, the Company, on behalf of itself, his attorneys, its officers,
directors and agents, acquits and forever discharges Liberman and his
representatives, agents and assigns (collectively, the "Released Liberman
Parties"), from any and all charges, controversies, claims, wages, rights,
agreements, actions, costs or expenses, causes of action, obligations, damages,
losses, promises and liabilities of whatever kind or nature (such as claims for
attorneys' fees), in law or equity or otherwise, whether known or unknown,
suspected or unsuspected, from the beginning of time to the date it signs this
Release, provided, however, that nothing in this Release shall be deemed a
release of the following claims: (a) claims for defense and indemnification to
which the Company may be


                                       11
<PAGE>
entitled pursuant to common or statutory law by reason of its role as Liberman's
employer; and (b) claims to enforce the Agreement or this Release.

            The Company, its attorneys, officers, directors, and agents
expressly agree that the Agreement and this Release extend to all claims of
every nature and kind, known or unknown, suspected or unsuspected, vested or
contingent, past, present or future, arising from or attributable to any alleged
act or omission of Liberman occurring prior to the execution of this Release,
including, without limitation, claims arising from Liberman's employment.

                  Supplemental Civil Code Section 1542 Waiver

            The Parties are aware of and have been advised by counsel of
California Civil Code Section 1542, which provides as follows:

            "A GENERAL RELEASE DOES NOT EXTEND TO CLAIMS WHICH THE CREDITOR DOES
NOT KNOW OR SUSPECT TO EXIST IN HER FAVOR AT THE TIME OF EXECUTING THE RELEASE,
WHICH IF KNOWN BY HIM MUST HAVE MATERIALLY AFFECTED HER SETTLEMENT WITH THE
DEBTOR."

            With full awareness and understanding of this provision, as to the
claims released by this Release, the Parties hereby waive all rights, that this
provision or any comparable provision under any state or federal law may give to
them. They intend the mutual general releases set forth in this Release to apply
to claims which they do not presently know to exist at this time. They
understand that the facts with respect to which this Release is given may
hereafter prove to be different from the facts now known or believed by them
(other than as to representations and warranties contained herein), and they
hereby accept and assume the risk thereof and agree that this Release shall be
and shall remain, in all respects, effective and not subject to termination or
rescission by reason of any such difference in facts.

              Supplemental Representation and Warranty of No Fraud

            By signing this Release, in exchange for the Company's release of
unknown claims by waiving Civil Code section 1542 above, Liberman represents and
warrants that up to the time of this Release, he did not engage in fraud or
other intentionally unlawful conduct relating in any way to, or arising from or
in connection with, his employment with the Company. The Company represents and
warrants that it is not aware of any fraud or other intentionally unlawful
conduct by Liberman with respect to performance of his duties for the Company.

Dated: May 17, 2004               GREGORY R. LIBERMAN, AN INDIVIDUAL


                                  /s/ Gregory R. Liberman
                                  ----------------------------------------------

Dated: May 17, 2004               CYTRX CORPORATION


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


                                       12
<PAGE>
                                   EXHIBIT B

                              Letter of Reference

                      [to be typed on Company letterhead]

                                      Date

Name
Company
Address
City, State Zip

Re: Gregory R. Liberman

Dear Name:

      I am writing to provide a reference for Gregory R. Liberman.

      Greg Liberman was employed by CytRx Corporation (the "Company") and held
the title General Counsel and Corporate Secretary during his employment. During
the term of Mr. Liberman's employment, he was responsible for managing the
Company's worldwide legal affairs, policy and strategy. Mr. Liberman played a
significant and valuable role as a member of the Company's senior management
team. The Company valued not only his legal skills, which are extremely high,
but also his strategic insights and business acumen.

      We wish Mr. Liberman the best in his future endeavors.

                                   Sincerely,




                                   Authorized Officer


                                       13