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SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
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SCHEDULE 13G
(Rule 13d-102)
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INFORMATION TO BE INCLUDED IN STATEMENTS PURSUANT TO
RULES 13d-1(b), (c) AND (d) AND AMENDMENTS
THERETO FILED PURSUANT TO 13d-2 UNDER THE
SECURITIES EXCHANGE ACT OF 1934
(Amendment No. 1)*
VION PHARMACEUTICALS INC.
(Name of Issuer)
Common Stock, $.01 Par Value
(Title of Class of Securities)
927624106
(CUSIP Number)
December 31, 1999
(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which
this Schedule is filed:
[X] Rule 13d-1(b)
[ ] Rule 13d-1(c)
[ ] Rule 13d-1(d)
___________
* The remainder of this cover page shall be filled out for a
reporting person's initial filing on this form with respect to the
subject class of securities, and for any subsequent amendment containing
information which would alter the disclosures provided in a prior cover
page.
The information required in the remainder of this cover page shall
not be deemed to be "filed" for the purpose of Section 18 of the
Securities Exchange Act of 1934 ("Act") or otherwise subject to the
liabilities of that section of the Act but shall be subject to all other
provisions of the Act (however, see the Notes).
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Schedule 13G PAGE 3 of 6
CUSIP No. 927624106
(1) NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Morgens, Waterfall, Vintiadis & Co., Inc.
132674766
________________________________________________________________________
(2) CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
(a) [ ]
(b) [X]
________________________________________________________________________
(3) SEC USE ONLY
________________________________________________________________________
(4) CITIZENSHIP OR PLACE OF ORGANIZATION
New York
________________________________________________________________________
NUMBER OF (5) SOLE VOTING POWER
776,784
SHARES _________________________________________________________
BENEFICIALLY (6) SHARED VOTING POWER
0
OWNED BY _________________________________________________________
EACH (7) SOLE DISPOSITIVE POWER
776,784
REPORTING _________________________________________________________
PERSON WITH (8) SHARED DISPOSITIVE POWER
0
________________________________________________________________________
(9) AGGREGATE AMOUNT BENEFICIALLY OWNED
BY EACH REPORTING PERSON
776,784
________________________________________________________________________
(10) CHECK BOX IF THE AGGREGATE AMOUNT
IN ROW (9) EXCLUDES CERTAIN SHARES [ ]
________________________________________________________________________
(11) PERCENT OF CLASS REPRESENTED
BY AMOUNT IN ROW (9)
4.26%
________________________________________________________________________
(12) TYPE OF REPORTING PERSON
IA
________________________________________________________________________
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Schedule 13G PAGE 4 OF 6
CUSIP No. 927624106
ITEM 1(a). NAME OF ISSUER:
VION PHARMACEUTICALS INC.
ITEM 1(b). ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES:
4 Science Park, New Haven, Connecticut 06511
ITEM 2(a). NAME OF PERSON FILING:
Morgens, Waterfall, Vintiadis & Co., Inc.
ITEM 2(b). ADDRESS OF PRINCIPAL OFFICE OR, IF NONE, RESIDENCE:
The business address of Morgens, Waterfall, Vintiadis &
Co., Inc. is 10 East 50th St., New York NY 10022.
ITEM 2(c). CITIZENSHIP:
New York
ITEM 2(d). TITLE OF CLASS OF SECURITIES:
common stock, $.01 par value
ITEM 2(e). CUSIP NUMBER:
927624106
ITEM 3. IF THIS STATEMENT IS FILED PURSUANT TO 13d-1(b) OR 13d-2(b) OR
(c), CHECK WHETHER THE PERSON FILING IS A:
(a) [ ] Broker or dealer registered under Section 15 of the
Act
(b) [ ] Bank as defined in Section 3(a)(6) of the Act
(c) [ ] Insurance Company as defined in Section 3(a)(19) of
the Act
(d) [ ] Investment Company registered under Section 8 of the
Investment Company Act of 1940
(e) [X] Investment Adviser registered under Section 203 of
the Investment Advisers Act of 1940: see Rule 13d-
1(b)(1)(ii)(E)
(f) [ ] Employee Benefit Plan, Pension Fund which is subject
to the provisions of the Employee Retirement Income
Security Act of 1974 or Endowment Fund; see Rule
13d-1(b)(1)(ii)(F)
(g) [ ] Parent Holding Company, in accordance with Rule 13d-
1(b)(ii)(G);
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Schedule 13G PAGE 5 OF 6
CUSIP No. 927624106
(h) [ ] Savings Associations as defined in Section 3(b) of
the Federal Deposit Insurance Act;
(i) [ ] Church Plan that is excluded from the definition of
an investment company under Section 3(c)(14) of the
Investment Company Act of 1940;
(j) [ ] Group, in accordance with Rule 13d-1(b)(1)(ii)(J).
IF THIS STATEMENT IS FILED PURSUANT TO Rule 13d-1(c),
CHECK THIS BOX. [ ]
ITEM 4. OWNERSHIP.
Morgens, Waterfall, Vintiadis & Co., Inc. ("MWV & Co.")
(a) Amount beneficially owned: 776,784
(b) Percent of class: 4.26%
(c) Number of shares as to which such person has:
(i) sole power to vote or to direct the vote
776,784
(ii) shared power to vote or to direct the vote
0
(iii) sole power to dispose or to direct the
disposition of
776,784
(iv) shared power to dispose or to direct the
disposition
0
MWV & Co., an investment adviser registered under Section
203 of the Investment Advisers Act of 1940, as amended,
holds for the accounts of its investment advisory clients,
and thereby beneficially owns, within the meaning of Rule
13d-3 under the Securities Exchange Act of 1934, the
foregoing shares of Common Stock.
ITEM 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS.
If this statement is being filed to report the fact that as of the
date hereof the reporting person has ceased to be the beneficial owner
of more than five percent of the class of securities, check the
following [ X ].
ITEM 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER
PERSON.
Not applicable.
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Schedule 13G PAGE 6 OF 6
CUSIP No. 927624106
ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH
ACQUIRED THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING
COMPANY.
Not applicable.
ITEM 8. IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP.
Not applicable.
ITEM 9. NOTICE OF DISSOLUTION OF GROUP.
Not applicable.
ITEM 10. CERTIFICATION. (if filing pursuant to Rule 13d-1(c))
By signing below each Reporting Person certifies that, to
the best of its knowledge and belief, the securities referred to above
were not acquired and are not held for the purpose of or with the effect
of changing or influencing the control of the issuer of the securities
and were not acquired and not held in connection with or as a
participant in any transaction having that purpose or effect.
SIGNATURES
After reasonable inquiry and to the best of our knowledge and
belief, the undersigned certify that the information set forth in this
statement is true, complete and correct.
DATED: February 15, 2000
______________________________
John C. "Bruce" Waterfall,
as President, on behalf of
Morgens, Waterfall, Vindiatis
& Co., Inc.
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