As filed with the Securities and Exchange Commission on November 4, 1997
                                                       Registration No. 33-
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549



                                    FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933

                                 _______________


                           VION PHARMACEUTICALS, INC.
             (Exact name of registrant as specified in its charter)

       DELAWARE                                                  13-3671221
       (State or other juris-                                  (I.R.S. Employer
       diction of incorporation                                Identification
       or organization)                                        Number)


                                 4 SCIENCE PARK
                          NEW HAVEN, CONNECTICUT 06511
                                 (203) 498-4210
(Address,  including zip code,  and telephone  number,  including  area code, of
registrant's principal executive offices)

                           VION PHARMACEUTICALS, INC.
                   AMENDED AND RESTATED 1993 STOCK OPTION PLAN
                            (full title of the plan)
                                 ______________

                                   JOHN SPEARS
                      PRESIDENT AND CHIEF EXECUTIVE OFFICER
                           VION PHARMACEUTICALS, INC.
                                 4 SCIENCE PARK
                          NEW HAVEN, CONNECTICUT 06511
                                 (203) 498-4210

(Name, address,  including zip code, and telephone number,  including area code,
of agent for service)

                                 ______________


Copies of all communications, including all communications sent to the agent for
service, should be sent to:

                             D. TERENCE JONES, ESQ.
                                  WIGGIN & DANA
                                ONE CENTURY TOWER
                          NEW HAVEN, CONNECTICUT 06508
                                 (203) 498-4400
                                _______________

<TABLE>
<CAPTION>
                                                   CALCULATION OF REGISTRATION FEE
------------------------------------------------------------------------------------------------------------------------------------
<S>                                <C>                       <C>                        <C>                       <C>
                                                              Proposed Maximum           Proposed Maximum          Amount of
Title of Securities to be           Amount to be              Offering Price Per         Aggregate Offering        Registration Fee
Registered                          Registered                Share(1)                   Price(1)
------------------------------------------------------------------------------------------------------------------------------------
Common Stock $.01 par value
per share...........                500,000 shares (2)        $5.57                      $2,785,000.00             $843.94
====================================================================================================================================
</TABLE>

(1)   The  price  is  estimated  solely  for  the  purpose  of  calculating  the
      registration  fee pursuant to Rule  457(h)(1).  The offering price and fee
      are computed based on the average of the high and low prices of the Common
      Stock as reported on the NASDAQ Small Cap Market on October 29, 1997.

(2)   Does not include  1,000,000  shares  previously  registered on October 27,
      1995 and October 22, 1996  pursuant  to a  seperate registration statement
      for which a fee was paid on such filing dates.

================================================================================







                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3.  INCORPORATION OF DOCUMENTS BY REFERENCE

             The  following  documents,  which are on file  with the  Commission
(File No. 0-26534),  are incorporated in this Prospectus by reference and made a
part hereof:

         (a) The  Company's  Annual  Report on Form  10-KSB  for the year  ended
December 31, 1996.

         (b) The Company's  Quarterly  Report on Form 10-QSB for the three month
period ended March 31, 1997.

         (c) The Company's  Quarterly  Report on Form 10-QSB for the three month
period ended June 30, 1997.

         (d) The  description of the Company's  Common Stock contained in Item 1
of the Company's Registration Statement on Form 8-A filed July 31, 1995.

         All documents filed by the Company  pursuant to Sections 13(a),  13(c),
14 or 15(d) of the  Exchange  Act  subsequent  to the date of this  Registration
Statement and prior to the  termination  of this offering  shall be deemed to be
incorporated  by reference  into this  Registration  Statement  and to be a part
hereof from the  respective  dates of filing of such  documents.  Any  statement
contained in a document  incorporated  or deemed to be incorporated by reference
herein  shall be deemed to be modified  or  superseded  for all  purposes to the
extent that a statement  contained in this  Registration  Statement or any other
subsequently  filed  document  that is also  incorporated  by  reference  herein
modifies  or  supersedes  such  statement.  Any such  statements  so modified or
superseded  shall  not be  deemed,  except  as so  modified  or  superseded,  to
constitute a part of this Registration Statement.

ITEM 4.  DESCRIPTION OF SECURITIES

                  Not applicable.

ITEM 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL

                  None.


                                      II-1









ITEM 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS

                  The  Certificate of  Incorporation  and By-Laws of the Company
provide that the Company shall  indemnify,  to the full extent  permitted by the
Delaware General Corporation Law ("GCL") as set forth in Section 145 of the GCL.

                  In  accordance   with  Section   102(a)(7)  of  the  GCL,  the
Certificate of Incorporation of the Company eliminates the personal liability of
directors to the Company or its  stockholders for monetary damages for breach of
a fiduciary  duty as a director  with certain  limited  exceptions  set forth in
Section 102(a)(7).

ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED

                  Not applicable.

ITEM 8.  EXHIBITS

Exhibit
No.               Description
-------           -----------

4                 Vion Pharmaceuticals, Inc. Amended and Restated 1993 Stock 
                    Option Plan, as amended

5                 Opinion of Wiggin & Dana

23.1              Consent of Ernst & Young LLP

23.2              Consent of Wiggin & Dana (to be filed as part of Exhibit 5)

24                Power of Attorney (included on signature page)

ITEM 9.  UNDERTAKINGS

              (a)    The undersigned registrant will:

              (1)    File,  during  any  period  in  which  it  offers  or sells
                     securities, a post-effective amendment to this registration
                     statement to:

              (i)    Include any additional or changed  material  information on
                     the plan of distribution.

              (2)    For  determining  any liability  under the Securities  Act,
                     treat each  post-effective  amendment as a new registration
                     statement of the securities offered


                                      II-2








                     and the offering of the  securities  at that time to be the
                     initial bona fide offering.

              (3)    File a post-effective amendment to remove from registration
                     any of the securities  that remain unsold at the end of the
                     offering.


                                      II-3








                                   SIGNATURES

              Pursuant to the  requirements  of the  Securities  Act of 1933, as
amended, the registrant certifies that it has reasonable grounds to believe that
it meets all of the requirements for filing on Form S-8 and has duly caused this
registration statement to be signed on its behalf by the undersigned,  thereunto
duly authorized, in the City of New Haven, State of Connecticut,  on November 4,
1997.


                                       VION PHARMACEUTICALS, INC.


                                       By: /s/ John A. Spears
                                           ---------------------------
                                           John A. Spears
                                           President and Chief Executive Officer


                                POWER OF ATTORNEY

              KNOW ALL MEN BY THESE  PRESENTS,  that each person whose signature
appears  below  constitutes  and appoints John A. Spears and Thomas Klein as his
true and lawful attorneys-in-fact and agents, each acting alone, with full power
of substitution and resubstitution, for him and in his name, place and stead, in
any and all  capacities,  to sign  any or all  amendments  to this  Registration
Statement,  including post-effective  amendments, and to file the same, with all
exhibits thereto, and all documents in connection therewith, with the Securities
and Exchange Commission,  granting unto said  attorneys-in-fact  and agents, and
each of them,  full power and authority to do and perform each and every act and
thing requisite and necessary to be done in and about the premises,  as fully to
all intents and purposes as he might or could do in person,  and hereby ratifies
and confirms all that said  attorneys-in-fact  and agents, each acting alone, or
their  substitute or substitutes,  may lawfully do or cause to be done by virtue
hereof.

              Pursuant to the  requirements  of the  Securities  Act of 1933, as
amended,  this  registration  statement  has been signed below by the  following
persons in the capacities and on the dates indicated.


Signature                     Title                                  Date
---------                     -----                                  ----


/s/ William R. Miller         Chairman of the Board          November 4, 1997
--------------------------                                           ----
William R. Miller



/s/ John A. Spears            President, Chief Executive     November 4, 1997
--------------------------    Officer and Director                   ----
John A. Spears                 



/s/ Alan C. Sartorelli        Director                       November 4, 1997
--------------------------                                           ----
Alan C. Sartorelli, Ph.D.



                                      II-4







/s/ Michel C. Bergerac              Director               November 4, 1997
-------------------------------                                    ----
Michel C. Bergerac



/s/ Frank T. Cary                   Director               November 4, 1997
-------------------------------                                    ----
Frank T. Cary



/s/ A.E. Cohen                      Director               November 4, 1997
-------------------------------                                    ----
A.E. Cohen



/s/ James L. Ferguson               Director               November 4, 1997
-------------------------------                                    ----
James L. Ferguson



/s/ Michael C. Kent                 Director               November 4, 1997
-------------------------------                                    ----
Michael C. Kent



/s/ E. Donald Shapiro               Director               November 4, 1997
-------------------------------                                    ----
E. Donald Shapiro



/s/ Walter Wriston                  Director               November 4, 1997
-------------------------------                                    ----
Walter Wriston





                                      II-5









/s/ Thomas E. Klein              Vice President - Finance,    November 4, 1997
----------------------------     Chief Financial Officer              ----
Thomas E. Klein                  and Treasurer (Principal
                                 Financial and Accounting
                                 Officer)                
                                 



                                      II-6
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 12834}]
{"company-data": {"conformed-name": "VION PHARMACEUTICALS INC", "cik": "0000944522", "assigned-sic": "2836", "irs-number": "133671221", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-39407", "film-number": "97707078"}, "business-address": {"street1": "4 SCIENCE PARK", "city": "NEW HAVEN", "state": "CT", "zip": "06511", "phone": "2034984210"}, "mail-address": {"street1": "FOUR SCIENCE PARK", "city": "NEW HAVEN", "state": "CT", "zip": "06511"}, "former-company": {"former-conformed-name": "ONCORX INC", "date-changed": "19950615"}}
As filed with the Securities and Exchange Commission on November 4, 1997
                                                       Registration No. 33-
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933

                                 _______________

                           VION PHARMACEUTICALS, INC.
             (Exact name of registrant as specified in its charter)

       DELAWARE                                                  13-3671221
       (State or other juris-                                  (I.R.S. Employer
       diction of incorporation                                Identification
       or organization)                                        Number)

                                 4 SCIENCE PARK
                          NEW HAVEN, CONNECTICUT 06511
                                 (203) 498-4210
(Address,  including zip code,  and telephone  number,  including  area code, of
registrant's principal executive offices)

                           VION PHARMACEUTICALS, INC.
                   AMENDED AND RESTATED 1993 STOCK OPTION PLAN
                            (full title of the plan)
                                 ______________

                                   JOHN SPEARS
                      PRESIDENT AND CHIEF EXECUTIVE OFFICER
                           VION PHARMACEUTICALS, INC.
                                 4 SCIENCE PARK
                          NEW HAVEN, CONNECTICUT 06511
                                 (203) 498-4210

(Name, address,  including zip code, and telephone number,  including area code,
of agent for service)

                                 ______________

Copies of all communications, including all communications sent to the agent for
service, should be sent to:

                             D. TERENCE JONES, ESQ.
                                  WIGGIN & DANA
                                ONE CENTURY TOWER
                          NEW HAVEN, CONNECTICUT 06508
                                 (203) 498-4400
                                _______________
CALCULATION OF REGISTRATION FEE
------------------------------------------------------------------------------------------------------------------------------------
Proposed Maximum           Proposed Maximum          Amount of
Title of Securities to be           Amount to be              Offering Price Per         Aggregate Offering        Registration Fee
Registered                          Registered                Share(1)                   Price(1)
------------------------------------------------------------------------------------------------------------------------------------
Common Stock $.01 par value
per share...........                500,000 shares (2)        $5.57                      $2,785,000.00             $843.94
====================================================================================================================================
(1)   The  price  is  estimated  solely  for  the  purpose  of  calculating  the
      registration  fee pursuant to Rule  457(h)(1).  The offering price and fee
      are computed based on the average of the high and low prices of the Common
      Stock as reported on the NASDAQ Small Cap Market on October 29, 1997.

(2)   Does not include  1,000,000  shares  previously  registered on October 27,
      1995 and October 22, 1996  pursuant  to a  seperate registration statement
      for which a fee was paid on such filing dates.

================================================================================

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3.  INCORPORATION OF DOCUMENTS BY REFERENCE

             The  following  documents,  which are on file  with the  Commission
(File No. 0-26534),  are incorporated in this Prospectus by reference and made a
part hereof:

         (a) The  Company's  Annual  Report on Form  10-KSB  for the year  ended
December 31, 1996.

         (b) The Company's  Quarterly  Report on Form 10-QSB for the three month
period ended March 31, 1997.

         (c) The Company's  Quarterly  Report on Form 10-QSB for the three month
period ended June 30, 1997.

         (d) The  description of the Company's  Common Stock contained in Item 1
of the Company's Registration Statement on Form 8-A filed July 31, 1995.

         All documents filed by the Company  pursuant to Sections 13(a),  13(c),
14 or 15(d) of the  Exchange  Act  subsequent  to the date of this  Registration
Statement and prior to the  termination  of this offering  shall be deemed to be
incorporated  by reference  into this  Registration  Statement  and to be a part
hereof from the  respective  dates of filing of such  documents.  Any  statement
contained in a document  incorporated  or deemed to be incorporated by reference
herein  shall be deemed to be modified  or  superseded  for all  purposes to the
extent that a statement  contained in this  Registration  Statement or any other
subsequently  filed  document  that is also  incorporated  by  reference  herein
modifies  or  supersedes  such  statement.  Any such  statements  so modified or
superseded  shall  not be  deemed,  except  as so  modified  or  superseded,  to
constitute a part of this Registration Statement.

ITEM 4.  DESCRIPTION OF SECURITIES

                  Not applicable.

ITEM 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL

                  None.

                                      II-1

ITEM 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS

                  The  Certificate of  Incorporation  and By-Laws of the Company
provide that the Company shall  indemnify,  to the full extent  permitted by the
Delaware General Corporation Law ("GCL") as set forth in Section 145 of the GCL.

                  In  accordance   with  Section   102(a)(7)  of  the  GCL,  the
Certificate of Incorporation of the Company eliminates the personal liability of
directors to the Company or its  stockholders for monetary damages for breach of
a fiduciary  duty as a director  with certain  limited  exceptions  set forth in
Section 102(a)(7).

ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED

                  Not applicable.

ITEM 8.  EXHIBITS

Exhibit
No.               Description
-------           -----------

4                 Vion Pharmaceuticals, Inc. Amended and Restated 1993 Stock 
                    Option Plan, as amended

5                 Opinion of Wiggin & Dana

23.1              Consent of Ernst & Young LLP

23.2              Consent of Wiggin & Dana (to be filed as part of Exhibit 5)

24                Power of Attorney (included on signature page)

ITEM 9.  UNDERTAKINGS

              (a)    The undersigned registrant will:

              (1)    File,  during  any  period  in  which  it  offers  or sells
                     securities, a post-effective amendment to this registration
                     statement to:

              (i)    Include any additional or changed  material  information on
                     the plan of distribution.

              (2)    For  determining  any liability  under the Securities  Act,
                     treat each  post-effective  amendment as a new registration
                     statement of the securities offered

                                      II-2

                     and the offering of the  securities  at that time to be the
                     initial bona fide offering.

              (3)    File a post-effective amendment to remove from registration
                     any of the securities  that remain unsold at the end of the
                     offering.

                                      II-3

                                   SIGNATURES

              Pursuant to the  requirements  of the  Securities  Act of 1933, as
amended, the registrant certifies that it has reasonable grounds to believe that
it meets all of the requirements for filing on Form S-8 and has duly caused this
registration statement to be signed on its behalf by the undersigned,  thereunto
duly authorized, in the City of New Haven, State of Connecticut,  on November 4,
1997.

                                       VION PHARMACEUTICALS, INC.

                                       By: /s/ John A. Spears
                                           ---------------------------
                                           John A. Spears
                                           President and Chief Executive Officer

                                POWER OF ATTORNEY

              KNOW ALL MEN BY THESE  PRESENTS,  that each person whose signature
appears  below  constitutes  and appoints John A. Spears and Thomas Klein as his
true and lawful attorneys-in-fact and agents, each acting alone, with full power
of substitution and resubstitution, for him and in his name, place and stead, in
any and all  capacities,  to sign  any or all  amendments  to this  Registration
Statement,  including post-effective  amendments, and to file the same, with all
exhibits thereto, and all documents in connection therewith, with the Securities
and Exchange Commission,  granting unto said  attorneys-in-fact  and agents, and
each of them,  full power and authority to do and perform each and every act and
thing requisite and necessary to be done in and about the premises,  as fully to
all intents and purposes as he might or could do in person,  and hereby ratifies
and confirms all that said  attorneys-in-fact  and agents, each acting alone, or
their  substitute or substitutes,  may lawfully do or cause to be done by virtue
hereof.

              Pursuant to the  requirements  of the  Securities  Act of 1933, as
amended,  this  registration  statement  has been signed below by the  following
persons in the capacities and on the dates indicated.

Signature                     Title                                  Date
---------                     -----                                  ----

/s/ William R. Miller         Chairman of the Board          November 4, 1997
--------------------------                                           ----
William R. Miller

/s/ John A. Spears            President, Chief Executive     November 4, 1997
--------------------------    Officer and Director                   ----
John A. Spears                 

/s/ Alan C. Sartorelli        Director                       November 4, 1997
--------------------------                                           ----
Alan C. Sartorelli, Ph.D.

                                      II-4

/s/ Michel C. Bergerac              Director               November 4, 1997
-------------------------------                                    ----
Michel C. Bergerac

/s/ Frank T. Cary                   Director               November 4, 1997
-------------------------------                                    ----
Frank T. Cary

/s/ A.E. Cohen                      Director               November 4, 1997
-------------------------------                                    ----
A.E. Cohen

/s/ James L. Ferguson               Director               November 4, 1997
-------------------------------                                    ----
James L. Ferguson

/s/ Michael C. Kent                 Director               November 4, 1997
-------------------------------                                    ----
Michael C. Kent

/s/ E. Donald Shapiro               Director               November 4, 1997
-------------------------------                                    ----
E. Donald Shapiro

/s/ Walter Wriston                  Director               November 4, 1997
-------------------------------                                    ----
Walter Wriston

                                      II-5

/s/ Thomas E. Klein              Vice President - Finance,    November 4, 1997
----------------------------     Chief Financial Officer              ----
Thomas E. Klein                  and Treasurer (Principal
                                 Financial and Accounting
                                 Officer)                
                                 

                                      II-6