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                       FIRST AMENDMENT
                              TO
            COMMON STOCK SALE/REPURCHASE AGREEMENT

     FIRST AMENDMENT dated November 12, 1997 ("Amendment") to the Common 
Stock Sale/Repurchase Agreement by and between ISRAEL CHEMICALS, LTD., an 
Iraeli limited liability company ("ICL") and SUPERGEN, INC., a Delaware 
company ("Company") dated as of August 6, 1997 ("Repurchase Agreement"). 
Unless otherwise defined herein, all capitalized terms shall have the 
meanings given them in the Repurchase Agreement.

                             RECITALS

     WHEREAS, pursuant to the Repurchase Agreement, the Company repurchased 
from ICL 740,000 shares of the common stock of the Company, with 1,831,000 
Remaining ICL Shares placed in escrow pursuant to an Escrow Agreement dated 
as of August 6, 1997 among ICL, the Company and the Escrow Agent named 
therein ("Escrow Agreement"); and

     WHEREAS, subject to the terms and conditions of Section 7(iii) of the 
Repurchase Agreement, the Remaining ICL Shares may not be transferred or 
otherwise disposed of by ICL (the "Lock-up") for the duration of the Lock-Up 
Period, and 915,500 of the Remaining ICL Shares (the "Option Shares") are 
further subject to a Put Option and a Call Option; and

     WHEREAS, the parties wish to effect a sale by ICL of 346,750 shares of 
the Remaining ICL Shares ("JLS Shares") to Jessup & Lamont Securities 
Corporation ("JLS") and, accordingly, (i) the Company has agreed to release 
the JLS Shares from the Lock-up and from Escrow (as said term is defined in 
the Escrow Agreement), (ii) ICL has agreed to permit the Company to assign 
its Call Option, (iii) ICL has agreed to transfer to the number of Option 
Shares subject to the Put Option and Call Option, that number of shares 
equal to 50% of the JLS Shares from such of the Remaining ICL Shares that are 
not Option Shares ("Transferred Option Shares"), and (iv) the parties agree 
to otherwise amend the Repurchase Agreement on the terms and subject to the 
conditions set forth below and to confirm and reaffirm the obligations of 
each party under the Repurchase Agreement, as so amended hereby.

     NOW, THEREFORE, the parties hereby agree that, on the terms and subject 
to the conditions hereinafter set forth, the Repurchase Agreement is hereby 
amended as follows:

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     1. SALE OF SHARES. Subject to the terms and conditions set forth herein, 
the parties agree that ICL may sell the JLS Shares to JLS at a price per 
share equal to $14.3125 per share on a date as soon as practical after the 
date of execution of this Amendment (the "Sale").

     2. RELEASE FROM LOCK-UP. As of the date hereof, in accordance with the 
terms of a letter of instructions to the Escrow Agent of even date herewith, 
the Company expressly released the JLS Shares from the Lock-up and from 
Escrow and the escrow arrangements set forth in the Escrow Agreement.

     3. NEW OPTION SHARES. Upon consummation of the Sale, ICL agrees to add 
to the number of Option Shares, the Transferred Option Shares, such that the 
total number of Option Shares subject to the Put Option and Call Option 
provisions of Section 9 of the Repurchase Agreement shall equal 1,088,875 
shares of the Company's common stock (the "New Option Shares"). For the 
avoidance of doubt, all of the New Option Shares shall, upon consummation of 
the Sale, be subject to ICL's Put Option and to the Company's Call Option 
under the terms of the Repurchase Agreement.

     4. ASSIGNMENT. The Company's Call Option with respect to the New Option 
Shares may be assigned by the Company; provided that the Company shall 
provide ICL three (3) business days' prior written notice of any such 
assignment ("Notice"). No assignment hereunder shall be made by the Company 
if it receives written notice from ICL, within two (2) business days' from 
ICL's receipt of the Notice, that ICL is prohibited from selling to, or 
otherwise transacting business with, the purported assignee under the laws of 
the State of Israel.

     5. CONDITIONS PRECEDENT. The Sale and the agreements set forth above 
shall be subject to delivery by the Company or its counsel, prior to the 
Sale, of appropriate instructions or other documentation required by the 
Transfer Agent and the Escrow Agent to effect (i) release of the Certificate 
in Escrow by the Escrow Agent to the Transfer Agent, and (ii) delivery by the 
Transfer Agent of substitute stock certificates representing the JLS Shares, 
the New Option Shares and the number of shares remaining after subtracting 
from the Remaining ICL Shares, the JLS Shares and the New Option Shares (the 
"New Remaining Shares") all as more specifically described in the letter of 
instructions referenced in Section 2 above.

     6. UNWIND. In the event that the Sale is not consummated on the terms 
described in Section 1 within 30 days of the date hereof, this Amendment 
shall have no further force and effect, and the parties agree that each shall 
return to their relative positions just prior to this Amendment under the 
terms and conditions of the Repurchase Agreement and the Escrow Agreement 
with respect to the Remaining ICL Shares, Option Shares, Lock-up and 
otherwise.

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     7. OTHER PROVISIONS OF REPURCHASE AGREEMENT. Except as expressly 
modified or supplemented by this Amendment, the terms, covenants and 
conditions of the Repurchase Agreement remain in full force and effect
as executed.

     IN WITNESS WHEREOF, the parties hereto have caused this First Amendment 
to be signed on the date first written above.

SUPERGEN, INC.                        ISRAEL CHEMICALS, LTD.

By: /s/ Dr. Joseph Rubinfeld          By:
   ---------------------------            ---------------------------
Name:                                     Name:
Title:                                    Time:





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