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                                                                   Exhibit 10.71


                               GENTA INCORPORATED
                            1998 STOCK INCENTIVE PLAN

                             STOCK OPTION AGREEMENT


         STOCK OPTION AGREEMENT (the "Agreement"), dated as of October 28, 1999,
between GENTA INCORPORATED, a Delaware corporation (the "Company"), and the
other party signatory hereto (the "Optionee"). Capitalized terms used here
without definition shall have the meanings ascribed thereto in the Company's
1998 Stock Incentive Plan (the "Plan").

         All options granted herein (the "Options") shall be appropriately
adjusted pursuant to Section 1.5.3 of the Plan.

         The Company hereby represents and warrants to Optionee that, as of the
date of this Agreement, the sum of the number of outstanding shares of Common
Stock and the number of shares of Common Stock underlying all outstanding
convertible or exercisable derivative securities is 63,510,163 shares. In the
event that the foregoing representation is inaccurate, the number of shares
underlying the Options granted under Section 1 of this Agreement shall be
proportionately adjusted.

         The Optionee hereby represents and warrants to the Company that, upon
commencing his employment with the Company on October 28, 1999, the Optionee was
not violating the terms of his employment with any third person, nor did the
commencement of his employment with the Company on October 28, 1999 provide the
basis for a claim of such a violation.
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         In consideration of the foregoing and of the mutual undertakings set
forth in this Agreement, the Company and the Optionee agree as follows:

         SECTION 1. Grant of Options.

         (a) In consideration of the commencement of his employment by the
Company on October 28, 1999, the Company hereby grants to the Optionee Options
(the "Initial Options") to purchase 3,175,508 shares of the Company common
stock, par value $.001 (the "Common Stock"), at an initial exercise price per
share of $2.67 (the "Exercise Price"). These Initial Options are exercisable
immediately subject to the satisfaction of the Option Conditions (defined
below); provided, however, the unvested portion of the Common Stock issuable
upon exercise of the Initial Option shall be subject to the nontransferability,
forfeiture and repayment provisions of Section 2, 5 and 7 hereof, respectively,
until such shares vest in accordance with the following vesting schedule: 25% of
the Initial Options shall vest immediately: the remaining 75% of the Initial
Options and Common Stock issuable upon exercise thereof shall vest in 36
substantially equal installments on the last day of each month commencing
November 30, 1999; and provided, further, that the Initial Options granted
hereunder shall not be exercisable until all of the following conditions (the
"Option Conditions") have been satisfied: (x) the Company's Amended and Restated
Certificate of Incorporation has been amended to increase the Company's
authorized capital stock by an amount sufficient to permit the issuance of
Common Stock upon the exercise or conversion of all options, warrants and
convertible securities issued by the Company, including all of the Options
granted pursuant to this Agreement (the "Reservation Requirements"); and (y) the
Company's shareholders shall have approved an amendment to the Plan authorizing
an increase in the shares of Common Stock available under the Plan sufficient to
satisfy the Options referred to herein. The Company shall use its best efforts,
subject to



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applicable law, to obtain shareholder approval of such amendments; provided,
however, that nothing in this Section 1(a) shall be interpreted so as to require
the Company pay a consent fee or hire third party proxy solicitors.

         (b) The Company hereby grants to the Optionee Options (the "FDA
Option") to purchase 793,877 shares of Common Stock at the Exercise Price;
provided, however, that this FDA Option and the Common Stock issuable upon
exercise thereof shall only vest when the Optionee has been employed by the
Company for six years (the "Term Condition") and provided, further, that in no
event shall this FDA Option be exercisable unless all Option Conditions have
been satisfied. The FDA Option is immediately exercisable; provided, however,
that the Common Stock issuable upon exercise of the FDA Option shall be subject
to the nontransferability, forfeiture and repayment provisions of Section 2, 5
and 7 hereof, respectively. Notwithstanding the foregoing, the Term Condition
shall be waived in respect of this FDA Option and the FDA Option and Common
Stock issuable upon exercise thereof shall vest in their entirety when the
Company has received from the Food and Drug Administration a letter providing
that Company's product G3139, or its substantial equivalent, is approved for
marketing in any indication.

         (c) The Company hereby grants to the Optionee Options (the "Market
Capitalization Option") (and, together with the FDA Option, the "Performance
Options") to purchase 793,877 shares of Common Stock at the Exercise Price;
provided, however, that this Market Capitalization Option and the Common Stock
issuable upon exercise thereof shall only vest upon the satisfaction of the Term
Condition; and provided, further, that in no event shall this Market
Capitalization Option be exercisable unless all Option Conditions have been
satisfied. The Market Capitalization Option is immediately exercisable;
provided, however, the unvested

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portion of the Common Stock issuable upon exercise of the Market Capitalization
Option shall be subject to the nontransferability, forfeiture and repayment
provisions of Section 2, 5 and 7 hereof, respectively. Notwithstanding the
foregoing, the Term Condition shall be waived in respect of this Market
Capitalization Option and the Market Capitalization Option and Common Stock
issuable upon exercise thereof shall vest in its entirety when the average of
the product of the Fair Market Value of the Company Common Stock (or any
successor security issued as a replacement for Company Common Stock) multiplied
by the number of shares of Company Common Stock outstanding and issuable upon
exercise of all warrants, options and convertible securities, during any 60
consecutive calendar day period, exceeds $541,106,489.

         (d) All the options described above may from time to time hereinafter
be referred to singularly as an "Option" and collectively as the "Options."



         SECTION 2. Nontransferability.

         (a) No Option shall be assignable or transferable, voluntarily or
involuntarily, by operation of law, or otherwise, and any such assignment or
transfer which may be attempted shall be null and void and of no effect;
provided, however, that this Section 2 shall not prevent transfers by will or by
the laws of descent and distribution. During the lifetime of the Optionee, the
Options shall be exercisable only by the Optionee.

         (b) Until a share of Common Stock vests in accordance with the
provisions of Section 1(a), (b) or (c), as the case may be, the Optionee
acknowledges that the Optionee may not, and the Optionee agrees that the
Optionee shall not, transfer or assign the Optionee's rights to such share of
Common Stock or to any cash payment related thereto. Until a share of Common
Stock so vests, no attempt to transfer or assign such shares or the right to any
cash

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payment related thereto, whether by transfer, pledge, hypothecation or otherwise
and whether voluntary or involuntary, by operation of law or otherwise, shall
vest the transferee or assignee with any interest or right in or with respect to
such share of Common Stock or such cash payment, and the attempted transfer or
assignment shall be of no force and effect.



         SECTION 3. Certificates; Custodianship.

         (a) Reasonably promptly after Optionee has exercised his right to
acquire any such shares of Common Stock already vested pursuant to the
provisions of Section 1 or Section 6 of this Agreement, but in no event more
than ten (10) business days after such date, the Company (i) shall cause to be
issued certificates evidencing such shares of Common Stock, including such
legends as the Company deems necessary or appropriate to comply with federal and
applicable state securities laws, and (ii) shall cause such certificates to be
delivered to the Optionee (or such Optionee's legal representative, beneficiary
or heir), together with any other property directly related to such vested
shares of Common Stock of the Optionee.

         (b) Reasonably promptly after the date that the Optionee exercises his
right to purchase any shares of Common Stock that have not theretofore vested or
been forfeited, but in no event more than ten (10) business days after such
date, provided that the Company has first received a stock power endorsed by the
Optionee in blank with respect to such shares of Common Stock, the Company shall
issue stock certificates, registered in the name of the Optionee, evidencing
such shares of Common Stock. Each such certificate shall bear the following
legend:

          "The transferability of this certificate and the shares of stock
     represented hereby are subject to the restrictions, terms and conditions
     (including forfeiture and restrictions against transfer) contained in the
     Genta Incorporated 1998 Stock Incentive Plan and an

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     Agreement entered into between the registered owner of such shares and
     Genta Incorporated. A copy of the Plan and Agreement is on file in the
     office of the Secretary of Genta Incorporated."

         Such legend shall not be removed from the certificates evidencing such
exercised shares of Common Stock until such shares vest pursuant to the
provisions of Section 1 and Section 6 of this Agreement.

         (c) Each certificate issued pursuant to Section 3(b) hereof, together
with the stock powers relating to such shares of Common Stock, shall be
deposited by the Company with a custodian designated by the Company (the
"Certificate Custodian"). The Company may designate itself as Certificate
Custodian hereunder. The Company shall cause such Certificate Custodian to issue
to the Optionee a receipt evidencing the certificates held by it which are
registered in the name of the Optionee.

         (d) Reasonably promptly after any previously unvested shares of Common
Stock vest pursuant to the provisions of Section 1 or Section 6 of this
Agreement, but in no event more than ten (10) business days after such date, the
Company (i) shall cause to be issued certificates evidencing such shares of
Common Stock, free of the legend provided in Section 3(b) hereof, but including
such legends as the Company deems necessary or appropriate to comply with
federal and applicable state securities laws, and (ii) shall cause such
certificates to be delivered to the Optionee (or such Optionee's legal
representative, beneficiary or heir), together with any other property directly
related to such vested shares of Common Stock of the Optionee held by the
Certificate Custodian pursuant to Section 3(e) hereof.

         (e) Any securities or other property (excluding cash dividends)
received by the Optionee with respect to a share of Common Stock as a result of
any stock dividend, stock split,

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recapitalization, merger, consolidation, combination or exchange of shares and
for which the issue date of such Common Stock occurs prior to such event but
which has not vested as of the date of such event will not vest until such share
of Common Stock vests and shall be promptly deposited with the Certificate
Custodian as though such securities and other property were part of such share.



         SECTION 4. Method of Exercise.

         (a) The Options or any part thereof may be exercised only by the giving
of written notice to the Company on such form and in such manner as the
Committee shall prescribe. Such written notice must be accompanied by payment of
the full purchase price for the number of shares being purchased. Such payment
may be made by one or a combination of the following methods:

             (i) by a certified or official bank check (or the equivalent
thereof acceptable to the Company);

             (ii) by delivery of shares of Common Stock having a Fair Market
Value on such date of exercise equal to part or all of the purchase price,
provided such shares of Common Stock would not upon delivery of such shares for
such purpose result in an accounting compensation charge with respect to the
shares of Common Stock used to pay the Exercise Price;

             (iii) by delivery of a promissory note issued by Optionee for up to
the full amount of the purchase price of the optioned shares (except that an
amount equal to the par value of Common Stock shall be paid in cash), on terms
acceptable to the Company, which promissory note shall be full recourse to the
Optionee personally for all amounts due thereunder

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and shall be fully secured by the Common Stock purchased pursuant to the
exercise of the Option;

             (iv) by payment through a broker-dealer sale and remittance
procedure pursuant to which the Optionee (i) shall provide written instructions
to a Company designated brokerage firm to effect the immediate sale of some or
all of the purchased Common Stock and remit to the Company, out of the sale
proceeds available on the settlement date, sufficient funds to cover the
aggregate exercise price payable for the purchased shares of Common Stock and
(ii) shall provide written directives to the Company to deliver the certificates
for the purchased shares of Common Stock directly to such brokerage firm in
order to complete the sale transactions; or

             (v) at the discretion of the Committee and to the extent permitted
by law, by such other method as the Committee may authorize, including, without
limitation, at the discretion of the Committee, by the withholding of shares
(valued at their Fair Market Value on the exercise date of the Common Stock)
underlying the Options.

         Pursuant to Section 3.2 of the Plan, it shall be a condition precedent
to the issuance of shares upon exercise of the Options that the Optionee shall
remit to the Company any amount sufficient to satisfy all applicable withholding
tax requirements, which may be satisfied through the withholding of Common Stock
as provided in Section 3.2.2 of the Plan. The date of the exercise of the
Options shall be the date on which written notice of exercise is delivered to
the Company, during normal business hours, at its address as provided in Section
10 of this Agreement, or if mailed, the date on which it is postmarked, provided
such notice is actually received.

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         (b) The Optionee agrees not to exercise any Options granted hereunder
until the later of (i) the day the Option Conditions are satisfied or (ii) one
day after the Optionee has been employed by the Company for six (6) months.
Furthermore, the Optionee agrees that any disposition of any Options (and any
shares of Common Stock issuable upon exercise of any options) will be carried
out in a manner consistent with Section 16(b) of the Securities and Exchange Act
of 1934, as amended, and any and all other applicable requirements of law.

         SECTION 5. Termination of Option.

         (a) Except as otherwise provided for under this Section 5, the
unexercised portion of the Initial Option shall expire and cease to be
exercisable at 12:01 a.m. on October 27, 2009; the unexercised portion of the
Market Capitalization Option shall expire and cease to be exercisable on the
tenth anniversary of the date such option vests in accordance with the
provisions of Section 1(b) hereof; and the unexercised portion of the FDA Option
shall expire and cease to be exercisable on the tenth anniversary of the date
such option vests in accordance with the provisions of Section 1(c) hereof.

         (b) Except as provided in Section 6 of this Agreement, upon termination
of the Optionee's employment with the Company or any of its subsidiaries for any
reason (including death), all unvested Options immediately shall terminate and
expire and all unvested shares of Common Stock exercised pursuant to any Option
hereunder shall be immediately and irrevocably forfeited except as provided in
Section 5(c) and (d) hereof.

         (c) Except as provided in Section 6 of this Agreement, if the
Optionee's employment with the Company or any of its subsidiaries terminates for
any reason other than death, the Options shall be exercisable but only to the
extent they were exercisable and vested at

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the time of such termination and only until the earlier of the expiration date
of such Options, or the expiration of one year following the date of
termination.

         (d) If the Optionee dies while still an employee of the Company or any
of its subsidiaries or following the termination of Optionee's employment with
the Company and its subsidiaries, but during the period in which any Option is
exercisable pursuant to Section 5(c) of this Agreement, such vested Option shall
be exercisable but only to the extent they were exercisable at the time of death
and only until the earlier of the expiration date of such Option or the first
anniversary of the date of the Optionee's death.



         SECTION 6. Acceleration of Vesting.

         If:

             (i) prior to the termination of Optionee's employment with the
Company, there is (A) a sale or other disposition of all or substantially all of
the assets of the Company or the product G3139 or its substantial equivalent,
(B) an acquisition of the Company by another entity by means of any transaction
or series of related transactions (including, without limitation, any
reorganization, merger or consolidation but, excluding any merger effected
exclusively for the purpose of changing the domicile of the Company) unless the
Company's stockholders as constituted immediately prior to such acquisition
will, immediately after such acquisition (by virtue of securities issued as
consideration for the Company's acquisition or otherwise) hold at least fifty
percent (50%) of the voting power of the surviving or acquiring entity and
unless the Company's directors as constituted immediately prior to such
acquisition, constitute a majority of directors of the surviving or acquiring
entity, or (C) an acquisition by any person or related group of persons (other
than the Company, a Company-sponsored employee benefit plan

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or such person or entity who as of September 14, 1999, beneficially owned
(within the meaning of Rule 13d-3 of the Securities Exchange Act of 1934, as
amended) more than fifty percent (50%) of the Company's Common Stock) of
securities possessing more than fifty percent (50%) of the total combined voting
power of the Company's outstanding securities; or

             (ii) Optionee's employment is terminated by the Company pursuant to
Section 10(d) of the employment agreement between you and the Company dated as
of October 28, 1999 (the "Employment Agreement")) or the Optionee terminates his
employment for Good Reason under subsection 10(e) of the Employment Agreement;
or

             (iii) prior to the termination of Optionee's employment with the
Company, at any time Lindsay Rosenwald, or after his death or incapacity, his
successor or legal representative (collectively "LR") directly or indirectly
(through Paramount Capital Management Inc., Paramount Capital Inc., or any fund,
trust or other entity for whom any of them, or any entity controlled by LR or
any of them, serves as investment advisor and/or general partner or otherwise
acts as an advisor or manager) ceases to control and direct at least 35% (thirty
five percent) of the total combined voting power of the Company's outstanding
securities; or

             (iv) prior to termination of Optionee's employment with the Company
the Company, within the meaning of any Bankruptcy Law:

                  (A)      commences a voluntary case,

                  (B)      consents to the entry of an order for relief against
                           it in an involuntary case,

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                  (C)      consents to the appointment of a Custodian of it or
                           for all or substantially all of its property, and
                           such Custodian is not discharged within 60 days; or

             (v) prior to termination of Optionee's employment with the Company,
a court of competent jurisdiction enters an order or decree under any Bankruptcy
Law that:

                  (A)      is for relief in any involuntary case against the
                           Company,

                  (B)      appoints a Custodian of the Company or for all or
                           substantially all of the property of the Company, or

                  (C)      orders the liquidation of the Company, and, in each
                           case, the order or decree remains unstayed and in
                           effect for 60 consecutive days;

then any Initial Options previously granted and the Common Stock issuable
thereof under this Agreement but not yet vested shall immediately vest. In
addition, all Performance Options that would have vested during the 12-month
period following the events set forth in this Section 6 (the "Section 6 Events")
shall vest, if a Section 6 Event occurs within such 12-month period, immediately
upon the occurrence of such Section 6 Events; provided, however, that no Options
granted hereunder shall be exercisable unless the Option Conditions have been
met. At the time the Section 6 Event occurs, the Options referred to in this
Section 6 shall be fully exercisable.

         The term "Bankruptcy Law" means Title 11 of the U.S. Code or any
similar federal, foreign or state law for the relief of debtors. The term
"Custodian" means any receiver, trustee, assignee, liquidator, examiner or
similar official under any Bankruptcy Law.

         SECTION 7. Right to Repayment.

         If in accordance with the terms of Section 5 of this Agreement,
Optionee forfeits any unvested shares of Common Stock received upon exercise of
an Option, Optionee acknowledges and agrees that the Certificate Custodian shall
surrender to the Company as soon

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as practicable after the effective date of such forfeiture all certificates for
such shares issued to Optionee by the Company pursuant to Section 3(b) of this
Agreement. As soon as practicable after such surrender, but in no event later
than 30 days after such surrender, Optionee shall be entitled to a payment by
the Company in an amount, in cash equal to the aggregate of the Exercise Prices
paid for each exercised but unvested share of Common Stock so forfeited.

         SECTION 8. Plan Provisions to Prevail.

         This Agreement is subject to all of the terms and provisions of the
Plan. Without limiting the generality of the foregoing, by entering into this
Agreement the Optionee agrees that no member of the Board of Directors or the
Committee shall be liable for any action or determination made in good faith
with respect to the Plan or any award thereunder or this Agreement. In the event
that there is any inconsistency between the provisions of this Agreement and of
the Plan, the provisions of the Plan shall govern. Notwithstanding the
foregoing, Section 2.10 of the Plan shall not apply to this Agreement.

         SECTION 9. Right of Discharge Preserved.

         Nothing in this Agreement shall confer upon the Optionee the right to
continue in the employ of the Company and its subsidiaries, or to continue in
the service of the Company and its subsidiaries as a consultant or director, or
affect any right which the Company and its subsidiaries may have to terminate
such employment or service.



         SECTION 10. Notices.

         All notices required or permitted hereunder shall be given in writing
by personal delivery; by confirmed facsimile transmission (with a copy
dispatched by express delivery or registered or certified mail); or by express
delivery via express mail or any reputable express

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courier service. Notice shall be addressed (a) to Genta Incorporated, c/o Dr.
Mark C. Rogers, Paramount Capital Inc., 787 Seventh Avenue, 48th Floor, New
York, New York 10019; and (b) to the Optionee at the address set forth on the
signature page hereto; or (c) as to either party, at such other address as may
be designated by notice in the manner set forth herein. Notices which are
delivered personally, by confirmed facsimile transmission, or by courier as
aforesaid, shall be effective on the date of delivery.



         SECTION 11. Successors and Assigns.

         This Agreement shall be binding upon and inure to the benefit of the
parties hereto and the successors and assigns of the Company and, to the extent
consistent with Section 5 of this Agreement and with the Plan, the heirs and
personal representatives of the Optionee.



         SECTION 12. Entire Contract; Waiver; Amendment.

         This Agreement constitutes the entire contract between the parties
hereto and supersedes all prior oral and written agreements between the parties
with regard to the subject matter hereof. No waiver of any breach or condition
of this Agreement shall be deemed to be a waiver of any other or subsequent
breach or condition, whether of like or different nature. This Agreement may be
amended as provided in Section 3.1.3 of the Plan. Headings are for convenience
only, and are not themselves part of the Agreement.



         SECTION 14. Severability.

         If any provision of this Agreement (including any provision of the Plan
that is incorporated herein by reference) shall hereafter be held to be invalid,
unenforceable or illegal in whole or in part, in any jurisdiction under any
circumstances for any reason, (a) such provision

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shall be reformed to the minimum extent necessary to cause such provision to be
valid, enforceable and legal while preserving the intent of the parties as
expressed in, and the benefits to the parties provided by, this Agreement and
the Plan or (b) if such provision cannot be so reformed, such provision shall be
severed from this Agreement and an equitable adjustment shall be made to this
Agreement (including, without limitation, addition of necessary further
provisions to this Agreement) so as to give effect to the intent as so expressed
and the benefits so provided. Such holding shall not affect or impair the
validity, enforceability or legality of such provision in any other jurisdiction
or under any other circumstances. Neither such holding nor such reformation or
severance shall affect or impair the legality, validity or enforceability of any
other provision of this Agreement or the Plan.



         SECTION 15. Governing Law.

         This Agreement shall be interpreted, construed and administered in
accordance with the laws of the State of New York, without giving effect to
principles of conflicts of laws, as they apply to contracts made, delivered and
performed in the State of New York.

         IN WITNESS WHEREOF, the parties hereto have executed this agreement as
of the date and year first written above.



                                             GENTA INCORPORATED


                                             By:
                                                -------------------------
                                                 Name:  Mark C. Rogers
                                                 Title: Chairman of the Board of
                                                        Directors



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                                             OPTIONEE

                                             Dr. Raymond P. Warrell, Jr.


                                             ----------------------------

                                             Address:

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                                             Social Security Number:

                                             ----------------------------