<PAGE>
U.S. SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
<TABLE>
<S> <C> <C>
----------------------------
======================= OMB APPROVAL
FORM 4 OMB Number: 3235-0287
======================= STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Expires: December 31, 2001
Estimated average burden
[ ] CHECK THIS BOX IF NO Filed pursuant to Section 16(a) of the Securities hours per response......0.5
LONGER SUBJECT TO SECTION 16. Exchange Act of 1934, Section 17(a) of the -----------------------------
FORM 4 OR FORM 5 OBLIGATIONS Public Utility Holding Company Act of 1935 or
MAY CONTINUE. SEE INSTRUCTION 1(b) Section 30(f) of the Investment Act of 1940
</TABLE>
<TABLE>
<S> <C> <C> <C>
==============================================================================================================================
1. Name and Address of 2. Issuer Name and Ticker 6. Relationship of Reporting Person to Issuer
Reporting Person* or Trading Symbol (Check all applicable)
KESSMAN ALAN VION PHARMACEUTICALS, X Director 10% Owner
INC. (VION) ----- ----
--------------------------------------------------------
(Last) (First) (Middle) X Officer Other (specify below)
3. IRS Identification Number 4. Statement for ----- ----
of Reporting Person, if Month/Year (give title below)
C/O VION PHARMACEUTICALS, INC. an entity (voluntary)
4 Science Park NOVEMBER 2000
------------------------------ ----------------- President & CEO
Street 5. If Amendment, --------------------------------------------
Date of
NEW HAVEN CT 06511 Original 7. Individual or Joint/Group Filing
------------------------------ (Month/Year) (Check Applicable Line)
(City) (State) (Zip) X Form filed by One Reporting Person
---
Form filed by More than One Reporting
--- Person
===============================================================================================================================
</TABLE>
TABLE I - NON-DERIVATIVE SECURITIES ACQUIRED, DISPOSED OF, OR BENEFICIALLY OWNED
<TABLE>
<CAPTION>
==============================================================================================================================
1. Title of Security (Inst. 3) 2. Transaction Date 3. Transaction Code 4. Securities Acquired (A) or Disposed of (D)
(Mo/Day/Yr) (Inst. 8) (Inst. 3, 4 and 5)
---------------------------------------------------------------------
Code V Amount (A) or (D) Price
------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C>
Common Stock, $.01 par value 11/30/2000 M 12,756 A $5.7750
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==============================================================================================================================
<CAPTION>
==========================================================
5. Amount of 6. Ownership 7. Nature of
Securities Form: Indirect
Beneficially Direct (D) or Beneficial
Owned at Indirect (I) Ownership
End of Month (Instr. 4) (Instr. 4)
(Instr. 3 and 4)
----------------------------------------------------------
<S> <C> <C>
35,856(1) I (2)
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==========================================================
</TABLE>
Reminder: Report on a separate line for class of securities beneficially owned
directly or indirectly.
(Over)
(Print or Type Responses) SEC 1474 (7-96)
*If the form is filed by more than one reporting person, see Instruction
4(b)(v).
Page 1 of 2
<PAGE>
FORM 4 (CONTINUED)
TABLE II - DERIVATIVE SECURITIES ACQUIRED, DISPOSED OF, OR BENEFICIALLY OWNED
(E.G., PUTS, CALLS, WARRANTS, OPTIONS, CONVERTIBLE SECURITIES)
<TABLE>
<CAPTION>
===============================================================================================================================
1. Title of Derivative 2. Convers- 3. Transaction 4. Transaction 5. Number of Derivative 6. Date Exercisable and
Security (Instr. 3) ion Date Code (Instr. 8) Securities Acquired (A) Expiration Date
or (Mo/Day/Yr) or Disposed of (D) (Mo/Day/Yr)
Warrants to purchase Exercise (Instr. 3,4,5)
Common Stock, $0.01 Price of ------------------------------------------------------------------------
par value per share
("Common Stock") Derivative
Security Date Expiration
Code V (A) (D) Exercisable Date
-------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C>
Options to purchase $14.875 02/24/2000 A V 25,166 (3) 02/24/2010
Common Stock (incentive)
-------------------------------------------------------------------------------------------------------------------------------
Options to purchase $14.875 02/24/2000 A V 24,834 (3) 02/24/2010
Common Stock (non-qualified)
-------------------------------------------------------------------------------------------------------------------------------
Options to purchase $5.7750 11/30/2000 M 12,756 07/11/2000 01/11/2009
Common Stock
-------------------------------------------------------------------------------------------------------------------------------
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===============================================================================================================================
<CAPTION>
===========================================================================================
7. Title & Amount of 8. Price of 9. Number of 10. Ownership 11. Nature of
Underlying Derivative Derivative Form of Indirect
Securities Security Securities Derivative Beneficial
(Instr. 3 & 4) (Instr.5) Beneficially Security Ownership
Owned at Direct (D) (Inst. 4)
Month or
(Inst. 4) Indirect (I)
(Inst. 4)
--------------------
Amount
or
Number
of
Title Shares
--------------------------------------------------------------------------------------------
<C> <C> <C> <C> <C> <C>
Common 25,166 25,166 D
Stock
--------------------------------------------------------------------------------------------
Common 24,834 24,834 D
Stock
--------------------------------------------------------------------------------------------
Common 12,756 2,244 I (2)
Stock
--------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------
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============================================================================================
</TABLE>
Explanation of Responses:
(1) Includes 12,756 shares of common stock owned by CBK Associates, LLC after
the exercise of options as reflected on page 2.
(2) By CBK Associates, LLC, a family partnership, of which Mr. Kessman is a
controlling member.
(3) Options vest in four annual installments beginning February 24, 2001
/s/ Alan Kessman December 7, 2000
-------------------- ----------------
**Alan Kessman Date
** Intentional misstatements or omissions of facts constitute Federal Criminal
Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If
space is insufficient, see Instruction 6 for procedure. Potential persons
who are to respond to the collection of information contained in this
form are not required to respond unless the form displays a currently
valid OMB Number.
SEC 1474 (7/96)
Page 2 of 2
