UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 1)

Vion Pharmaceuticals, Inc.

Name of Issuer

Common Stock, par value $0.01

(Title of Class of Securities)

927624502

(CUSIP Number)

September 17, 2009

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

o Rule 13d-1(b)

x Rule 13d-1(c)

o 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 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).

SCHEDULE 13G

1

NAMES OF REPORTING PERSONS:

Southpaw Asset Management LP

2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

(a)

o

(b)

o

3

SEC USE ONLY

4

CITIZENSHIP OR PLACE OF ORGANIZATION:

Delaware

NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH

5

SOLE VOTING POWER

0

6

SHARED VOTING POWER

0

7

SOLE DISPOSITIVE POWER

0

8

SHARED DISPOSITIVE POWER

0

9

AGGREGATE AMOUNT BENEFICALLY OWNED BY EACH REPORTING PERSON:

0

10

CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES:

o

11

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

0.0%

12

TYPE OF REPORTING PERSON:

PN

SCHEDULE 13G

1

NAMES OF REPORTING PERSONS:

Southpaw Holdings LLC

2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

(a)

o

(b)

o

3

SEC USE ONLY

4

CITIZENSHIP OR PLACE OF ORGANIZATION:

Delaware

NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH

5

SOLE VOTING POWER

0

6

SHARED VOTING POWER

0

7

SOLE DISPOSITIVE POWER

0

8

SHARED DISPOSITIVE POWER

0

9

AGGREGATE AMOUNT BENEFICALLY OWNED BY EACH REPORTING PERSON:

0

10

CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES:

o

11

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

0.0%

12

TYPE OF REPORTING PERSON:

OO

SCHEDULE 13G

1

NAMES OF REPORTING PERSONS:

Southpaw Credit Opportunity Master Fund LP

2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

(a)

o

(b)

o

3

SEC USE ONLY

4

CITIZENSHIP OR PLACE OF ORGANIZATION:

Cayman Islands

NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH

5

SOLE VOTING POWER

0

6

SHARED VOTING POWER

0

7

SOLE DISPOSITIVE POWER

0

8

SHARED DISPOSITIVE POWER

0

9

AGGREGATE AMOUNT BENEFICALLY OWNED BY EACH REPORTING PERSON:

0

10

CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES:

o

11

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

0.0%

12

TYPE OF REPORTING PERSON:

PN

SCHEDULE 13G

1

NAMES OF REPORTING PERSONS:

Kevin Wyman

2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

(a)

o

(b)

o

3

SEC USE ONLY

4

CITIZENSHIP OR PLACE OF ORGANIZATION:

United States

NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH

5

SOLE VOTING POWER

0

6

SHARED VOTING POWER

0

7

SOLE DISPOSITIVE POWER

0

8

SHARED DISPOSITIVE POWER

0

9

AGGREGATE AMOUNT BENEFICALLY OWNED BY EACH REPORTING PERSON:

0

10

CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES:

o

11

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

0.0%

12

TYPE OF REPORTING PERSON:

IN

SCHEDULE 13G

1

NAMES OF REPORTING PERSONS:

Howard Golden

2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

(a)

o

(b)

o

3

SEC USE ONLY

4

CITIZENSHIP OR PLACE OF ORGANIZATION:

United States

NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH

5

SOLE VOTING POWER

0

6

SHARED VOTING POWER

0

7

SOLE DISPOSITIVE POWER

0

8

SHARED DISPOSITIVE POWER

0

9

AGGREGATE AMOUNT BENEFICALLY OWNED BY EACH REPORTING PERSON:

0

10

CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES:

o

11

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

0.0%

12

TYPE OF REPORTING PERSON:

IN

SCHEDULE 13G

ITEM 1(a)

NAME OF ISSUER:

Vion Pharmaceuticals, Inc. (the "Issuer")

ITEM 1(b)

ADDRESS OF ISSUER’S PRINICIPAL EXECUTIVE OFFICES:

4 Science Park

New Haven, CT

ITEM 2(a)

NAME OF PERSON FILING:

This statement is filed on behalf of the following persons (collectively, the “Reporting Persons”):

(i) Southpaw Asset Management LP (“Southpaw Management”)

(ii) Southpaw Credit Opportunity Master Fund LP

(iii) Southpaw Holdings LLC (“Southpaw Holdings”)

(iv) Kevin Wyman

(v) Howard Golden

As of September 18, 2009, none of the Reporting Persons beneficially owns any shares of par value $0.01 per share common stock of the Issuer ("Common Stock") (including any shares of Common Stock issuable  upon conversion of 7.75% convertible senior notes due 2012 of the Issuer (“Convertible Senior Notes”)) nor has the power to vote or dispose of any shares of Common  Stock (including any shares of Common Stock issuable upon conversion of Convertible Senior Notes).

ITEM 2(b)

ADDRESS OF PRINCIPAL BUSINESS OFFICE OR, IF NONE, RESIDENCE:

Four Greenwich Office Park

Greenwich, CT 06831

ITEM 2(c)

CITIZENSHIP:

(i) Southpaw Asset Management LP is a limited partnership organized under the laws of Delaware.

(ii) Southpaw Credit Opportunity Master Fund LP is a limited partnership organized under the laws of the Cayman Islands.

(iii) Southpaw Holdings LLC is a limited liability company organized under the laws of Delaware.

(iv) Kevin Wyman is an individual having citizenship in the United States.

(v) Howard Golden is an individual having citizenship in the United States.

ITEM 2(d)

TITLE OF CLASS OF SECURITIES: Common Stock

ITEM 2(e)

CUSIP NUMBER: 927624502

ITEM 3

IF THIS STATEMENT IS FILED PURSUANT TO §§ 240.13d-1(b) OR 240.13d-2(b) OR (c), CHECK WHETHER THE FILING PERSON IS:

Not applicable.

ITEM 4

OWNERSHIP:

As of September 18, 2009, none of the Reporting Persons beneficially owns any shares of Common Stock (including any shares of Common Stock issuable upon conversion of Convertible Senior Notes) nor has the power to vote or dispose of any shares of Common Stock (including any shares of Common Stock issuable upon conversion of Convertible Senior Notes).

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 5 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.

ITEM 7

IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY OR CONTROL PERSON.

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

CERTIFICATIONS.

By signing below, each of the Reporting Persons certifies that, to the best of his 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 are not held in connection with or as a participant in any transaction having that purpose or effect.