SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549
                                 --------------

                                    FORM 8-K

                                 CURRENT REPORT

                       Pursuant to Section 13 or 15(d) of
                       the Securities Exchange Act of 1934


         Date of Report (Date of earliest event reported): May 20, 1998




                       AMERICAN BIOGENETIC SCIENCES, INC.
               (Exact Name of Registrant as Specified in Charter)

                                    DELAWARE
                    (State of jurisdiction of incorporation)


       0-19041                                             11-2655906
(Commission File No.)                          (IRS Employer Identification No.)


           1375 AKRON STREET, COPIAGUE, NEW YORK                   11726
          (Address of Principal Executive Offices)               (Zip Code)


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


                                 NOT APPLICABLE
          (Former Name or Former Address, if Changed Since Last Report)








ITEM 5.     OTHER EVENTS

            On May 20, 1998, the Company  completed a private placement to three
accredited  investors  (the  "Investors")  of an aggregate of  $4,000,000  of 5%
Convertible  Debentures due May 20, 2001 (the  "Debentures") and three series of
Warrants to purchase up to an aggregate of 261,228 shares of the Company's Class
A Common Stock (the "Warrants").

            The Debentures  will become  convertible to the extent of 25% of the
principal  amount thereof  commencing on September 17, 1998,  with an additional
25% of the principal amount of the Debentures becoming first convertible on each
of October 17,  1998,  November  16,  1998 and  December  16,  1998  (subject to
potential  acceleration in certain instances) at a conversion price equal to 87%
(if converted before November 17, 1998), 86% (if converted  between November 17,
1998 and February 14, 1999), 85% (if converted between February 15, 1999 and May
20, 1999) or 84% (if converted after May 20, 1999), respectively, of the average
of the closing  bid prices of the  Company's  Class A Common  Stock for the five
consecutive  trading days  immediately  preceding  the date of conversion of the
Debentures (the "Variable  Conversion  Price");  provided,  however,  that in no
event may the conversion price be greater than $1.9375 per share, which was 125%
of such  average  price  over the five  consecutive  trading  days  prior to the
consummation of the transaction (the "Fixed Conversion Price").  Interest on the
Debentures  is payable only on maturity,  conversion,  redemption  or when other
payment is made on the Debentures in cash or, if registered for resale under the
Securities  Act of 1933,  as amended (the  "Securities  Act"),  in shares of the
Company's  Class A Common Stock valued at the  applicable  Debenture  conversion
price. Any Debenture outstanding on May 20, 2001 will be automatically converted
into  Class A Common  Stock of the  Company as of that date.  In  addition,  the
Company may require  conversion of outstanding  Debentures after May 20, 2000 if
the closing bid price of its Class A Common Stock on the trading day immediately
preceding  its giving of notice of conversion  to  Debentureholders  is at least
$3.0625. In the event the Company would be required to issue more than 4,000,000
shares of its Class A Common Stock upon conversion of all of the Debentures (the
"Conversion Limit"), the Company will have the option of: (i) issuing additional
shares  of  Common  Stock  if  stockholder  approval  has  been  obtained  or if
stockholder approval is not required in order to comply with applicable rules of
the market upon which its Class A Common  Stock is traded or (ii) paying cash to
the  holder in an amount  equal to the  principal  amount  of  Debentures  being
converted  plus an amount  equal to the number of shares of Class A Common Stock
that would be otherwise issuable upon conversion of the Debentures multiplied by
the difference  between the highest sales price of the Company's Common Stock on
the date of conversion and the applicable  Debenture  conversion  price.  In the
event of a merger or other business combination or corporate reorganization as a
result of which the stockholders of the Company immediately prior thereto own in
the aggregate less than 50% of the voting power of the ultimate parent resulting
from such transaction or the Company  transfers all or substantially  all of its
assets to another  person,  then the  Debentureholders  may  participate in such
transaction  as a  class  on the  same  basis  as if  the  Debentures  had  been
converted.  In the  event a  purchase,  tender  or  exchange  offer  is made and
accepted by the holders of more than 50% of the voting power of all  outstanding
shares of Common Stock immediately prior thereto,  the holders of the Debentures
are entitled to


                                       -2-





redeem any  outstanding  Debentures  at a redemption  price equal to 115% of the
then outstanding principal amount of the Debentures plus accrued interest on the
Debentures.

            In  connection  with the sale and  issuance of the  Debentures,  the
Company  also  issued to the  Investors  the  Warrants in series  entitling  the
Investors to purchase,  at an exercise price of $1.9141 per share,  an aggregate
of  65,307  shares  of the  Company's  Class A  Common  Stock at any time to and
including May 19, 2002,  65,307 shares of the Company's Common Stock (subject to
pro rata reduction to the extent the original principal amount of the Debentures
issued to the  Investors  is not  outstanding  on the day such  Warrant is first
exercised)  at any time between  November  20, 1998 and  November 19, 2002,  and
130,614  shares  of the  Company's  Class A Common  Stock  (subject  to pro rata
reduction to the extent the original  principal amount of the Debentures  issued
to the Investors is not outstanding on the day such Warrant is first  exercised)
at any time between May 20, 1999 and May 19, 2003.

            The  Debentures  and  the  Warrants  contain  various  anti-dilution
adjustments,  including,  among other things,  in the event of stock  dividends,
splits  and  combinations,  capital  reorganizations  and,  in the  case  of the
Warrants,  certain  issuances of Class A Common  Stock and various  common stock
equivalents  at an  effective  purchase  price per share  which is less than the
exercise price of the Warrants.

            The Company has also entered into a  Registration  Rights  Agreement
with the Investors pursuant to which, among other things, the Company has agreed
to file,  on or prior to July 19,  1998,  a  registration  statement  under  the
Securities  Act covering the shares  issuable upon  conversion of the Debentures
and  exercise  of the  Warrants  and to  maintain  such  registration  statement
effective  for, in general,  54 months or, if earlier,  the date when all shares
subject  thereto are sold  pursuant to the  registration  statement  or Rule 144
promulgated  under the Securities  Act ("Rule 144"),  or are eligible to be sold
under Rule 144 without  volume or other  limitations.  Should such  registration
statement  not be timely filed or become  effective by September  17, 1998,  the
Company  will be required to pay each  Debentureholder  an amount equal to 1% of
the principal amount of such holder's Debentures for the first 30 days, 1.5% for
the  next 30 days  and 2% for  each 30 days  thereafter  that  the  registration
statement is not effective. If the registration statement is either not filed or
does not become  effective by November 16, 1998,  holders of Debentures  will be
entitled to require the Company to redeem their Debentures at a redemption price
equal to 130% of the outstanding principal amount thereof, plus accrued interest
thereon. All expenses of registration are to be borne by the Company, other than
underwriting discounts and selling commissions, and fees and expenses of counsel
employed by the Investors in excess of $5,000,  which are the obligations of the
Investors.

            As  compensation  for  the  placement  of  the  Debentures  and  the
Warrants, the Company paid Jesup & Lamont Securities Corporation,  the placement
agent, a commission of $200,000.

            Each of the three  Investors is an "accredited  investor" as defined
in Rule 501(a) of Regulation D under the Securities Act and  acknowledged in its
Securities  Subscription  Agreement that it was purchasing the  Debentures,  the
Warrants and the Class A Common Stock issuable upon conversion of the Debentures
and exercise of the Warrants for investment for its own account and


                                       -3-




not  with a view  towards  distribution.  The  Company  believes  the  exemption
afforded  under Section 4(2) of the Securities Act is applicable to the issuance
of the Debentures and Warrants.

            The  foregoing  is  a  brief  description  of  the  Debentures,  the
Warrants,   the  Registration  Rights  Agreement  and  Securities   Subscription
Agreements,  copies or forms of which  appear as  exhibits to this  Report.  The
foregoing  descriptions  thereof do not purport to be complete and are qualified
in their entirety by reference to such documents.

ITEM 7.     FINANCIAL STATEMENTS AND EXHIBITS

            (a)   Financial statements of businesses acquired: None

            (b)   Pro forma financial information: None

            (c)   Exhibits:

                  Exhibits:

                  4.1      Form of the Company's 5% Convertible Debentures.


                  99.1     Form of Securities Subscription Agreement between the
                           Company and each of the Investors.

                  99.2     Registration Rights Agreement between the Company and
                           each of the Accredited Investors.

                  99.3(a)  Form of the  Company's  Series WA  Warrant  issued to
                           each of the Investors

                  99.3(b)  Form of the  Company's  Series WB  Warrant  issued to
                           each of the Investors

                  99.3(c)  Form of the  Company's  Series WC  Warrant  issued to
                           each of the Investors




                                   SIGNATURES

            Pursuant to the requirements of the Securities Exchange Act of 1934,
the  Registrant  has duly  caused  this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                          AMERICAN BIOGENETIC SCIENCES, INC.
                                                     (Registrant)

Dated:   June 2, 1998                     By: /S/ JOSEF C. SCHOELL
                                              -------------------------
                                              Josef C. Schoell,
                                              Vice President-Finance


                                       -4-






                                  EXHIBIT INDEX
                                  -------------

Exhibit
Number                  Document
- ------                  --------

4.1               Form of the Company's 5% Convertible Debentures.

99.1              Form of Securities  Subscription Agreement between the Company
                  and each of the Investors.

99.2              Registration  Rights Agreement between the Company and each of
                  the Accredited Investors.

99.3(a)           Form of the Company's  Series WA Warrant issued to each of the
                  Investors

99.3(b)           Form of the Company's  Series WB Warrant issued to each of the
                  Investors

99.3(c)           Form of the Company's  Series WC Warrant issued to each of the
                  Investors