SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   FORM 10-K/A


|X|   Annual Report  Pursuant to Section 13 or 15(d) of the Securities  Exchange
      Act of 1934 For the fiscal year ended December 31, 1997.
           
                                       or

|_|   Transition  Report  Pursuant  to  Section  13 or 15(d)  of the  Securities
      Exchange  Act of 1934  For the  transition  period  from  ____________  to
      ____________.

                         Commission File Number: 0-19041

                       AMERICAN BIOGENETIC SCIENCES, INC.
--------------------------------------------------------------------------------
             (Exact name of registrant as specified in its charter)

           Delaware                                              11-2655906
-------------------------------                              -------------------
(State or other jurisdiction of                               (I.R.S. Employer
 incorporation or organization                               Identification No.)

  1375 Akron Street, Copiague, New York                           11726
----------------------------------------                     -------------------
(Address of principal executive offices)                        (Zip Code)

Registrant's telephone number, including area code:  (516) 789-2600

        Securities registered pursuant to Section 12(b) of the Act: None

           Securities registered pursuant to Section 12(g) of the Act:

                      Class A Common Stock, $.001 par value
                      -------------------------------------
                                (Title of Class)

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the  preceding 12 months (or for such  shorter  period that the  Registrant  was
required  to file  such  reports)  and  (2)  has  been  subject  to such  filing
requirements for the past 90 days. Yes [X]    No [_]

Indicate by check mark if disclosure of delinquent  filers  pursuant to Item 405
of Regulation  S-K is not contained  herein,  and will not be contained,  to the
best of Registrant's  knowledge,  in definitive proxy or information  statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. [X]

As of the close of business on March 13, 1998, there were outstanding 19,616,869
shares of the  registrant's  Class A Common  Stock and  1,725,500  shares of its
Class B Common Stock.  The  approximate  aggregate  market value (based upon the
closing price on The Nasdaq Stock  Market's  National  Market) of shares held by
non-affiliates of the registrant as of March 13, 1998 was $32,809,000.

                       DOCUMENTS INCORPORATED BY REFERENCE

                                      None


<PAGE>



                                     PART II

ITEM 5.    MARKET FOR THE REGISTRANT'S COMMON STOCK AND RELATED SECURITY HOLDER
-------    --------------------------------------------------------------------
           MATTERS
           -------

           The Company's Class A Common Stock ("Common  Stock") is traded on the
Nasdaq  National Market tier of The Nasdaq Stock Market under the trading symbol
MABXA.  The  following  table sets forth the high and low closing bid prices for
the  Company's  Common Stock for the periods  indicated,  as reported by Nasdaq,
without retail mark-us, mark-downs or commissions.

Fiscal Years                        High                       Low
------------                        ----                       ---

1997
----

First Quarter                       $6                       $3  3/8

Second Quarter                       3  15/16                 2  1/8

Third Quarter                        3  15/16                 2  15/16

Fourth Quarter                       3  3/4                   1  1/2

1996
----

First Quarter                        6  7/8                   2  7/16

Second Quarter                       8  1/8                   5

Third Quarter                        6  1/8                   4  3/16

Fourth Quarter                       6  1/16                  4

           There were  approximately 679 holders of record of Common Stock as of
March 13, 1998 (exclusive of  stockholders  whose shares are held in street name
by brokers, depositories and other institutional firms).

           The Company has not paid any cash dividends on its Common Stock since
its  inception and does not  anticipate  paying  dividends  for the  foreseeable
future.

           During the quarter  ended  December 31, 1997, a holder of $150,000 of
the Company's 7% Convertible  Debentures  converted such  debentures into 50,805
shares of the  Company's  Class A Common  Stock.  The Company  believes that the
exemption from registration afforded by Section 3(a)(9) of the Securities Act of
1933,  as amended (the "Act"),  is  applicable to the issuance of such shares as
such  issuance  involved a  security  exchanged  by the  Company  with  existing
securityholders  exclusively where no commission or other  remuneration was paid
or given directly or indirectly for soliciting such exchange.


                                       -2-

<PAGE>



           On November  26, 1997,  December 15, 1997 and December 30, 1997,  Mr.
Alfred J. Roach,  Chairman of the Board of Directors  and a director,  purchased
50,000,  100,000 and 100,000  shares,  respectively,  of the  Company's  Class B
Common Stock for $109,375, or $2.1875 per share;  $168,800, or $1.688 per share;
and $156,250, or $1.5625 per share, respectively,  the closing bid prices of the
Company's Class A Common Stock (into which the Company's Class B Common Stock is
convertible on a  share-for-share  basis) on the Nasdaq Stock Market's  National
Market on the  respective  dates.  Mr.  Roach  agreed to acquire  the shares for
investment and not with a view to the distribution thereof. The Company believes
that the  exemption  from  registration  afforded by Section  4(2) of the Act is
applicable to the issuance of such shares.

           In  connection  with a lease  agreement for certain  facilities,  the
Company may, at its option,  pay a portion of the annual lease  obligation  with
shares  of Class A Common  Stock  (the  "Issued  Shares")  plus a  warrant  (the
"Warrant")  to purchase an  identical  number of shares of Class A Common  Stock
(the "Warrant Shares"). The number of Issued Shares are computed by dividing the
lease  obligation  to be paid with  shares by the  average  market  price of the
Company's  Class A Common  Stock  during  the ten days  prior to  issuance.  The
Warrant Shares are to be exercisable for a period of four years from the date of
issuance at a price equal to the closing price of the underlying  Class A Common
Stock on the date the  Warrant is issued.  Pursuant to the lease  agreement,  on
November 28, 1997, the Company approved the issuance of 15,543 shares of Class A
Common Stock and a Warrant to purchase  15,543 shares of Class A Common Stock at
an exercise price of $2.13 per share. In connection with such  acquisition,  the
purchaser  agreed to acquire  the Issued  Shares,  the  Warrant  and the Warrant
Shares  for  investment  and  not  with  a  view  to the  distribution  of  such
securities.  In  connection  therewith,  the Company  has granted the  purchaser
certain rights to cause the Warrant Shares to be registered under the Act at the
Company's  expense.  The Company  believes that the exemption from  registration
afforded  by  Section  4(2) of the Act is  applicable  to the  issuance  of such
securities.





                                       -3-

<PAGE>




                                    PART III

ITEM 10.    DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT
--------    --------------------------------------------------

           The directors and executive officers of the Company are as follows:

Name                             Position

Alfred J. Roach                  Chairman of the Board, Chief Executive Officer
                                 and Director

Stephen H. Ip, Ph.D.             President, Chief Operating Officer and Director

Ellena M. Byrne                  Executive Vice President and Director

Timothy J. Roach                 Treasurer, Secretary and Director

Emer Leahy, Ph.D.                Senior Vice President-Business Development

James M. McLinden, Ph.D.         Vice President-Molecular Biology

Josef C. Schoell                 Vice President-Finance and Chief Financial 
                                 Officer

Gustav Victor Rudolf Born, M.D.  Director

Joseph C. Hogan, Ph.D.           Director

William G. Sharwell              Director

           ALFRED J. ROACH,  82, has been  Chairman of the Board of Directors of
the Company since its  organization  in September  1983 and, from September 1983
until  October  1988,  also served as President  of the  Company.  Mr. Roach has
served as  Chairman  of the  Board  and/or  President  of TII  Industries,  Inc.
("TII"), a corporation engaged in manufacturing and marketing telecommunications
products,  and its  predecessor  since its founding in 1964. Mr. Roach devotes a
majority of his time to the business of the Company.

           STEPHEN  H. IP,  Ph.D.,  51,  joined the  Company in January  1997 as
Executive Vice President and Chief Operating  Officer and was elected  President
and a  director,  in addition  to  continuing  as Chief  Operating  Officer,  in
January,  1998.  Prior to joining the Company,  Dr. Ip served as Vice President,
Corporate and Business Development at Paracelsian, Inc., a publicly-held company
engaged in clinical and  pre-clinical  development of drugs and  supplements for
the  treatment  of AIDS  and  cancer,  from  February,1996.  From  1990  through
December, 1995, Dr. Ip served as President, Chief Operating Officer and director
of CytoMed,  Inc.,  a  biopharmaceutical  company  engaged in the  research  and
development  of  synthetic  chemical  drugs  and  recombinant  proteins  for the
treatment of acute and chronic  diseases.  From 1984 through  1989,  he was Vice
President and a scientific co-founder of T Cell Sciences,  Inc., a biotechnology
company.


                                       -4-

<PAGE>



           ELLENA M. BYRNE, 47, has been Executive Vice President and a director
of the Company  since March 1995.  From January 1986 until  December  1991,  Ms.
Byrne served as Vice  President-Administration of the Company and, from December
1991 until March 1995, Ms. Byrne served in various  capacities with the Company,
including Director of Operations for Europe and Asia.

           TIMOTHY J. ROACH, 51, has been Treasurer, Secretary and a director of
the Company since  September  1983. He has also been  affiliated  with TII since
1974,  serving as its President since July 1980,  Chief Operating  Officer since
May 1987, Vice Chairman of the Board since October 1993, Chief Executive Officer
since January 1995 and a director  since  January  1978.  Mr. Roach devotes such
time as is necessary  to the business of the Company to discharge  his duties as
Treasurer,  Secretary  and a director.  Timothy J. Roach is the son of Alfred J.
Roach.

           EMER LEAHY, Ph.D., 32, rejoined the Company in December 1997, serving
as Senior Vice President-Business Development. From April 1995 to December 1997,
Dr. Leahy was employed by AMBI, Inc., a biotechnology and nutraceutical company,
as Vice President-Product  Development, and Director-Business Development, where
she coordinated licensing  technologies and products as well as participating in
corporate  acquisitions.  From  April  1994 to April  1995,  Dr.  Leahy was Vice
President-Neuroscience   and,   from  August  1993  to  April  1994,   was  Vice
President-Regulatory  Affairs of the Company.  From  February  1992 until August
1993,  Dr. Leahy was employed by  Boehringer  Ingelheim,  GmbH, a  multinational
pharmaceutical  company,  where she coordinated  clinical trials in Ireland.  In
addition,  from  October  1991  to  August  1993,  Dr.  Leahy  was  lecturer  in
Pharmacology at the Royal College of Surgeons of Ireland.

           JAMES H.  MCLINDEN,  Ph.D.,  47, has been Vice  President - Molecular
Biology of the Company since November 1991. Prior thereto (and since joining the
Company in January 1987),  Dr. McLinden served as Director of Molecular  Biology
of the Company.

           JOSEF  C.  SCHOELL,  48,  joined  the  Company  in  July  1992 as its
Controller and was elected Vice President-Finance and Chief Financial Officer in
July 1995.  Mr.  Schoell is a Certified  Public  Accountant  in the State of New
York.

           GUSTAV  VICTOR RUDOLF BORN,  M.D.,  D.Phil.,  F.R.S.,  76, has been a
director of the  Company  since  January  1997.  Since  1988,  Dr. Born has been
Research Director of The William Harvey Research Institute at St.  Bartholomew's
Hospital Medical College, London, England and Emeritus Professor of Pharmacology
in the University of London.  Among Dr. Born's  distinctions,  appointments  and
activities are: Fellowship and Royal Medal of the Royal Society;  and Foundation
President of the British Society for Thrombosis and Haemostasis.

           JOSEPH C. HOGAN,  Ph.D., 75, has been a director of the Company since
December  1983.  Dr. Hogan served as Dean of the College of  Engineering  of the
University of Notre Dame from 1967 to 1981, following which he performed various
services  for the  University  of Notre Dame until 1985,  where he remains  Dean
Emeritus.  From 1985 until his  retirement  in 1987,  Dr.  Hogan was Director of
Engineering Research and Resource Development at Georgia Institute of Technology
("Georgia Tech"). Dr. Hogan is a director of TII.

           WILLIAM G. SHARWELL,  D.C.S.,  77, has been a director of the Company
since October 1986.  Dr.  Sharwell was President of Pace  University in New York
from 1984 until his retirement in


                                       -5-

<PAGE>



1990.  He was Senior Vice  President of American  Telephone & Telegraph  Company
between 1976 and 1984,  and  previously  served as Executive  Vice  President of
Operations of New York Telephone  Company.  Dr.  Sharwell serves on the Board of
Directors of TII and as an  independent  general  partner of  Equitable  Capital
Partners,   L.P.  and  Equitable  Capital  Partners   (Retirement  Fund),  L.P.,
registered investment companies under the Investment Company Act of 1940.

           Directors serve until the next Annual Meeting of the  Shareholders of
the Company  following their election and until their respective  successors are
elected and qualified.

           Each  executive  officer is scheduled to hold office until the Annual
Meeting of Directors  which is scheduled to be held after each Annual Meeting of
Shareholders.  Any  executive  officer may be removed by the Board of  Directors
either with or without cause.

           There are no understandings between any director or executive officer
and any other person  pursuant to which any  director or  executive  officer was
elected as such.  Ms.  Byrne and Drs.  Ip and Leahy are  parties  to  employment
agreements with the Company.

SECTION 16(a) BENEFICIAL OWNERSHIP REPORTING COMPLIANCE

           Section 16(a) of the  Securities  Exchange Act requires the Company's
executive officers and directors, and persons who beneficially own more than 10%
of the Company's Common Stock, to file initial reports of ownership, and reports
of changes of ownership,  of the Company's equity securities with the Securities
and  Exchange  Commission  and furnish  copies of those  reports to the Company.
Based solely on a review of copies of the reports  furnished to the Company,  or
written  representation that no reports were required, the Company believes that
all reports  required to be filed by such persons with respect to the  Company's
year ended December 31, 1997 were timely filed.


                                       -6-

<PAGE>



ITEM 11.     EXECUTIVE COMPENSATION
--------     ----------------------

SUMMARY COMPENSATION TABLE

           The following table sets forth information  concerning the annual and
long-term  compensation  for services in all  capacities  to the Company  during
1995, 1996 and 1997 of the Company's chief executive  officer and each executive
officer  of the  Company  whose  annual  cash  compensation  for  1997  exceeded
$100,000:

                                                  ANNUAL          LONG-TERM
  NAME AND                                     COMPENSATION      COMPENSATION
  PRINCIPAL POSITION                 YEAR    SALARY      BONUS     OPTIONS

Alfred J. Roach, Chairman            1997   $250,000       --         --
  of the Board and Chief             1996   $250,000       --         --
  Executive Officer                  1995   $250,000       --      135,000

Stephen H. Ip, Executive Vice        1997   $146,000   $ 25,000    200,000
  President and Chief Operating
  Officer

Josef C. Schoell, Vice President-    1997   $103,000       --       25,000
  Finance                            1996   $ 95,000       --       10,000
                                     1995   $ 76,000       --       60,000

Paul E. Gargan, Former President     1997   $137,000       --         --
                                     1996   $162,000       --         --
                                     1995   $150,000       --       31,500
------------
(1)   Dr. Ip joined the Company in January 1997.




                                       -7-

<PAGE>



OPTION GRANTS IN LAST FISCAL YEAR

           The  following  table  contains  information  concerning  options  to
purchase shares of the Company's capital stock granted by the Company during the
year ended  December  31, 1997 to the  executive  officers  named in the Summary
Compensation  Table.  No stock  appreciation  rights  have been  granted  by the
Company.

<TABLE>
<CAPTION>
                                      INDIVIDUAL OPTIONS                        POTENTIAL          
                      ------------------------------------------------------    REALIZABLE VALUE   
                                    PERCENT                                     AT ASSUMED ANNUAL  
                      NUMBER OF     OF TOTAL                                    RATES OF STOCK     
                      SHARES        OPTIONS                                     PRICE APPRECIATION 
                      UNDERLYING    GRANTED TO     EXERCISE                     FOR OPTION TERM (2)
                      OPTIONS       EMPLOYEES IN   PRICE          EXPIRATION    -------------------
    NAME              GRANTED(1)    FISCAL YEAR    PER SHARE(1)   DATE           5%          10%
    ----              ----------    -----------    ------------   ----------    ---          ---
<S>                   <C>             <C>          <C>            <C>  <C>    <C>        <C>       
Stephen H. Ip         200,000         21.8%        $3.66          1/02/2007   $460,351   $1,166,619

Josef C. Schoell       25,000          2.7%        $3.47          1/20/2007   $ 54,557   $  138,257
</TABLE>
-------------

(1)   Exercisable  as to 25% of the  number of  shares  of Class A Common  Stock
      subject to the option  commencing six months after the date of grant, on a
      cumulative  basis.  The exercise  price of each of the options  granted to
      Messrs.  Ip and Schoell is the market value of the Class A Common Stock on
      the date of grant.

(2)   These  are  hypothetical   values  using  assumed  compound  growth  rates
      prescribed by the Securities and Exchange  Commission and are not intended
      to forecast possible future  appreciation,  if any, in the market price of
      the Company's Class A Common Stock.




                                       -8-

<PAGE>




OPTION EXERCISES IN LAST FISCAL YEAR AND YEAR-END VALUES

           No options to purchase  shares of the  Company's  capital  stock were
exercised   during  1997  by  the  executive   officers  named  in  the  Summary
Compensation  Table.  The following  table contains  information  concerning the
number of shares of Class A Common Stock underlying  unexercised options held at
December 31, 1997 by the executive  officers  named in the Summary  Compensation
Table.


                                                             VALUE OF
                                    NUMBER OF                UNEXERCISED
                                    UNEXERCISED              IN-THE-MONEY
                                    OPTIONS HELD AT          OPTIONS HELD AT
                                    FISCAL YEAR-END (#)      FISCAL YEAR-END ($)
                                    (EXERCISABLE/            (EXERCISABLE/
                    NAME            UNEXERCISABLE)           UNEXERCISABLE(1)
                    ----            -------------------      ----------------
          Alfred J. Roach             1,160,000/  0           $   0   /$   0

          Stephen H. Ip                   0    /200,000       $   0   /$   0

          Josef C. Schoell               95,000/130,000       $  9,375/$   0

          Paul E. Gargan (2)            164,000/  0           $  4,922/$   0


--------------
(1)   The closing price of the  Company's  Class A Common Stock The Nasdaq Stock
      Market's  National  Market on December 31, 1997 less the exercise price of
      each option.

(2)   Excludes options held by Dr. Gargan's wife.

EMPLOYMENT AGREEMENTs

           The Company is a party to an employment agreement with Dr. Stephen H.
Ip, dated  December 16, 1996,  under which Dr. Ip is serving as President of the
Company.  The agreement provides for a term expiring December 31, 1999, with the
Company and Dr. Ip having the right to terminate the agreement  without cause on
thirty and sixty days' notice, respectively.  In the event of termination of the
agreement by the Company  without cause,  Dr. Ip is to remain as a consultant to
the Company at his then existing compensation for a period of one year, provided
that the  consulting  and  compensation  arrangement  is to  terminate if Dr. Ip
enters into full-time  employment with a third party.  Under the agreement,  Dr.
Ip's current  annual  salary is $175,000  per annum.  Dr. Ip recieved a one-time
$25,000 bonus in connection with his entering into the agreement and is entitled
to an annual  bonus of up to 20% of his annual  salary  based on goals  mutually
agreed upon between the Company and Dr. Ip.



                                       -9-

<PAGE>



           The Company is also a party to an employment  agreement with Dr. Emer
Leahy,  dated November 12, 1997, under which Dr. Leahy is serving as Senior Vice
President-Business Development of the Company. The agreement provides for a term
expiring  November 30, 2001.  Under the agreement,  Dr.  Leahy's  current annual
salary is $150,000 per annum. Dr. Leahy is entitled to annual bonuses and salary
increases based upon performance,  as well as reimbursement for tuition fees for
an Executive MBA program.

           As part of their respective employment agreements,  Drs. Ip and Leahy
have agreed not to disclose confidential information about the Company during or
after employment and agreed not to compete with the Company during their term of
employment and, in certain instances, following employment.

REMUNERATION OF DIRECTORS

           Directors  receive no  compensation  for  service on the Board.  Each
director serving on the Audit Committee  receives a fee of $600 for each meeting
of the committee attended by that director in person and not telephonically. All
directors are reimbursed  for travel  expenses  incurred in attending  Board and
committee meetings.

           The Company's 1993 Non-Employee  Director Stock Option Plan, approved
by stockholders at the Company's 1993 Annual Meeting of  Stockholders,  provides
for the automatic  grant of an option to purchase 10,000 shares of the Company's
Class A Common Stock to each  non-employee  director holding office  immediately
after each annual meeting of stockholders. The exercise price for each option is
equal to the fair market value of the Company's Class A Common Stock on the date
of  grant.  All  options  have a term of five  years and are  exercisable,  on a
cumulative  basis, at the rate of one quarter of the number of shares subject to
the option in each year commencing one year after the date of the grant.

           See  "Executive   Compensation"   for   information   concerning  the
compensation  of Mr. Alfred J. Roach and Dr. Stephen H. Ip for their services as
executive officers of the Company.  The Company is also a party to an employment
agreement dated October 1, 1996 with Ms. Ellena M. Byrne,  pursuant to which Ms.
Byrne is serving as Executive  Vice  President of the  Company.  The  Employment
Agreement  provides  for  a  term  extending,   subject  to  certain  terms  and
conditions,  until September 30, 2001. Ms. Byrne's current annual salary is U.S.
$18,200 and (pound)50,000 Irish Pounds  (approximately U.S. $68,000 at March 31,
1998).  Dr.  Born  serves as a  consultant  to the Company for which he receives
compensation at the rate of $12,000 per annum.


                                      -10-

<PAGE>



ITEM 12.     SECURITY HOLDINGS OF CERTAIN STOCKHOLDERS AND MANAGEMENT
--------     --------------------------------------------------------

           The  following  table sets forth  information  at April 20, 1998 with
respect to the  beneficial  ownership of the Company's  Class A Common Stock and
Class B Common Stock by (i) each person known by the Company to beneficially own
more than 5% of the outstanding shares of Class A Common Stock or Class B Common
Stock, (ii) each director of the Company,  (iii) each executive officer named in
the Summary  Compensation Table in Item 11 of this Report and (iv) all executive
officers and  directors of the Company as a group.  Each share of Class A Common
Stock is entitled to one vote per share while each share of Class B Common Stock
is entitled  to ten votes per share.  The Company  understands  that,  except as
noted below,  each  beneficial  owner has sole voting and investment  power with
respect to all shares attributable to such owner.

<TABLE>
<CAPTION>
                             Class A Common Stock(1)         Class B Common Stock
                                             Percent                       Percent
Beneficial Owner             No. Shares     of Class         No. Shares    of Class
-----------------           ------------    --------         ----------    --------
<S>                         <C>               <C>            <C>              <C> 
Alfred J. Roach (2)         3,668,750(2)      16.3%          1,725,500        100%
                                            
Stephen H. Ip                  71,668(3)       *                --            --
                                            
Ellena M. Byrne               200,000(3)(4)    1.0%             --            --
                                            
Timothy J. Roach              595,000(3)       2.9%             --            --
                                            
Gustav V. R. Born              20,000(3)      *                 --            --
                                            
Joseph C. Hogan                50,000(3)      *                 --            --
                                            
William G. Sharwell            55,000(3)      *                 --            --
                                            
All executive officers                      
 and directors as a group                   
 (10 persons, including                     
  the foregoing)            4,930,918(5)      20.8%          1,725,500        100%
</TABLE>

----------------------------                    

(1)   Asterisk  indicates less than one percent.  Shares of Class A Common Stock
      subject to issuance  upon  conversion of Class B Common Stock into Class A
      Common  Stock and upon  exercise of options that were  exercisable  on, or
      become  exercisable  within 60 days after,  April 20, 1998 are  considered
      owned by the holder thereof and  outstanding for purposes of computing the
      percentage of outstanding Class A Common Stock that would be owned by such
      person,  but (except for the  computation  of beneficial  ownership by all
      executive   officers  and  directors  as  a  group)  are  not   considered
      outstanding for purposes of computing the percentage of outstanding  Class
      A Common Stock owned by any other person.

(2)   The address of Mr.  Roach is Route 2 - Kennedy  Avenue,  Guaynabo,  Puerto
      Rico  00657.  Beneficial  ownership  of  Class  A  Common  Stock  includes
      1,725,500  shares of Class A Common Stock issuable upon  conversion of the
      same  number of shares of Class B Common  Stock on a share for share basis
      and  1,160,000  shares  of Class A Common  Stock  subject  to  outstanding
      options.

                                              (Footnotes continued on next page)


                                      -11-

<PAGE>


(3)   Includes  shares of Class A Common  Stock  subject to options as  follows:
      Stephen H. Ip, 66,668;  Ellena M. Byrne,  165,000 (including 10,000 shares
      subject to options held by her husband); Timothy J. Roach, 595,000; Gustav
      V.R.  Born,  20,000;  Joseph C. Hogan,  40,000;  and William G.  Sharwell,
      45,000.

(4)   Includes  10,000  shares owned by Ms.  Byrne's son. The inclusion of these
      amounts  should not be  construed  as an  admission  that Ms. Byrne is the
      beneficial owner of these shares.

(5)   Includes 1,725,500 shares of Class A Common Stock issuable upon conversion
      of the same number of shares of Class B Common Stock and 2,336,668  shares
      of Class A Common Stock subject to outstanding options.

ITEM 13.     CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS
--------     ----------------------------------------------

           On January  17,  1997,  November  26,  1997,  December  15,  1997 and
December 30, 1997, Mr. Alfred J. Roach purchased  100,000,  50,000,  100,000 and
100,000  shares,  respectively,  of the  Company's  Class  B  Common  Stock  for
$343,750,  or $3.4375 per share;  $109,375,  or $2.1875 per share;  $168,800, or
$1.688 per share; and $156,250, or $1.5625 per share, respectively,  the closing
bid prices of the Company's Class A Common Stock (into which the Company's Class
B Common Stock is  convertible on a  share-for-share  basis) on The Nasdaq Stock
Market's National Market on the respective dates.



                                   SIGNATURES


Pursuant to the  requirements of Section 13 or 15(d) of the Securities  Exchange
Act of 1934,  the Company has duly caused this report to be signed on its behalf
by the undersigned, thereunto duly authorized.

                                             AMERICAN BIOGENETIC SCIENCES, INC.


Dated: April 30, 1998                        By:     /s/ Josef C. Schoell
                                                -------------------------
                                                 Josef C. Schoell
                                                 Vice President-Finance
                                                 (Principal Financial and 
                                                  Accounting Officer)


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