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                                                            EXHIBIT 10.43
                                       
                                 PROCEPT, INC.
                              840 MEMORIAL DRIVE
                        CAMBRIDGE, MASSACHUSETTS  02139


                                 CONFIDENTIAL
                                       
                               November 2, 1998
                                       
Dr. H. Laurence Shaw
President and Chief Executive Officer
Pacific Pharmaceuticals, Inc.
6730 Mesa Ridge Road, Suite A
San Diego, CA  92121

     Re:  LETTER OF INTENT

Dear Dr. Shaw:

     This letter is intended to confirm recent discussions between Procept,
Inc., a Delaware corporation ("Procept"), and Pacific Pharmaceuticals, Inc. , a
Delaware corporation ("Pacific") regarding the terms which will form the basis
for our efforts to reach a definitive agreement regarding the proposed merger
of Pacific and Procept (the "Merger").  It is expressly agreed that, with the
limited exceptions of Sections 2 and 4, which shall be legally binding, this
letter does not constitute a firm proposal, offer or enforceable agreement to
consummate the Merger, is not legally binding on either of the parties and
imposes no duty or obligation on either of them to proceed with the proposed
transaction.  In the event that a definitive agreement to consummate the Merger
is not signed by November 19, 1998, the binding provisions of Sections 2.1
shall terminate, and the parties shall have no further obligations except as
stated in Sections 2.2 and  4.

     1.   PREPARATION OF DEFINITIVE AGREEMENT.  Counsel for Procept and for
Pacific will prepare a definitive agreement for submission to and approval by
the boards of directors and stockholders of each of Procept and Pacific and
Procept will thereby succeed to and acquire the business of Pacific (the
"Business").  Procept and Pacific acknowledge agreement in principle to the
following terms and conditions of the transaction:

          1.1  PROPOSED MERGER.  For the consideration set forth below, Pacific
will merge with and into Procept.  All of the outstanding capital stock,
options, warrants and other rights to acquire an interest in the capital
structure of Pacific will convert into the aggregate securities specified in
Section 1.2 below.

          1.2  CONSIDERATION.  On the date of the closing of the transaction
(the "Closing Date"), Procept shall deliver:

               (a)  to the Pacific stockholders 2,755,000 shares of Procept
Common Stock (of which the 1,287,647 shares of Procept Common Stock that will
be issued in the Merger


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to the holders of Pacific Preferred Stock shall be accompanied by certain 
contractual rights identical to contractual rights held by purchasers in 
Procept's 1998 private placement); and

               (b)  to the holders of outstanding options and warrants to
purchase Pacific stock, options and warrants to purchase Procept Common Stock
exercisable for that number of shares of Procept Common Stock which such option
or warrant holder would have been entitled to receive if the underlying Pacific
shares had converted in the Merger, at an exercise price per share equal to the
aggregate exercise price of the Pacific option or warrant exchanged divided by
the number of shares of Procept Common Stock subject to the new option or
warrant, and otherwise having the same terms and conditions as the Pacific
option or warrant.

          1.3  CERTAIN ASSUMED RIGHTS AND OBLIGATIONS.  Each of Procept and
Pacific acknowledges that by virtue of the Merger, Procept will acquire the
equity interest of Pacific in BGDC and will be subject to the obligations of
Pacific to the other stockholders of BGDC.

          1.4  STOCKHOLDER APPROVAL; FAIRNESS OPINIONS.  Each of Procept and
Pacific will promptly seek stockholder approval of the Merger after the
execution of the definitive merger agreement.   Prior to the solicitation of
proxies or consents from stockholders (or the mailing of an information
statement in lieu thereof), each of Procept and Pacific will obtain fairness
opinions from a reputable investment banking firm with respect to the Merger,
copies of which shall be provided to the stockholders of each company.

          1.5  FORM OF TRANSACTION, TAX AND ACCOUNTING TREATMENT.  The final
form of the transaction will be determined by Procept and Pacific after
consultation with their legal, tax and accounting advisors.  It is currently
contemplated that the transaction will be tax-free to Procept, Pacific and
their respective stockholders.  Procept anticipates the transaction will be
recorded using "purchase accounting."

          1.6  EMPLOYMENT AND CONSULTING AGREEMENTS.  Certain Pacific employees
may enter into employment agreements or consulting and confidentiality
agreements.  Prior to the execution of a definitive agreement, the parties
shall identify each such person by name and title and determine his or her term
of employment or consultation and compensation.  Prior to the Closing Date, all
of such agreements will be completed and signed by all parties.

          1.7  REGISTRATION OF SHARES; RESTRICTIONS ON RESALE.  The shares of
Procept Common Stock delivered in the Merger will have been registered under
the Securities Act of 1933, as amended (the "Act"), on Form S-4.  As a result,
the shares of Procept Common Stock will be freely tradable following the
Merger, subject to the provisions of Rule 145 under the Act.

          1.8  TIMING.  It is the intention of the parties to sign the
definitive agreement no later than November 19, 1998.

          1.9  REPRESENTATIONS AND WARRANTIES.  The definitive agreement will
contain representations and warranties to the extent customary for merger
transactions involving the acquisition of a public company.

          1.10 CONDITIONS TO CLOSING.  As proposed to be structured, the
signing of the definitive agreement is conditioned on the approval of the
transaction by the Boards of Directors


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of Procept and Pacific.  The consummation of the transactions to be set forth 
in the definitive agreement shall be subject to the following additional 
terms and conditions:

               1.10.1    Each of Procept and Pacific shall have received
          satisfactory responses to its requests for information from the other
          party and each of the parties shall have completed its customary due
          diligence review to its satisfaction, including review of the
          financial results of the Business of Procept and Pacific for the last
          five years.
          
               1.10.2    Pacific and Procept shall each have received approval
          of their respective stockholders and all other approvals, clearances
          and consents from any governmental entities and other third parties
          necessary or desirable for the consummation of the Merger and the
          Pacific shares shall be free and clear of any lien or encumbrances.
          
               1.10.3    Procept or its independent public accountants shall
          have (i) completed a review of the revenues and expenses of the
          Business; (ii) confirmed to Procept's satisfaction that Pacific's
          financial statements fairly present in all material respects the
          results of operations and cash flows resulting from the Business in
          conformity with generally accepted accounting principles; and (iii)
          confirmed to Procept's satisfaction that Pacific's financial records
          are adequate to permit Procept to fulfill its SEC financial reporting
          obligations in connection with the exchange and in connection with
          Procept's future registered financings without unreasonable effort or
          expense.
          
               1.10.4    To the extent necessary, each holder of an outstanding
          Pacific option or warrant shall consent to the exchange of such
          option or warrant for an option or warrant exercisable for Procept
          Common Stock, as contemplated by Section 1.2(b) above.
          
               1.10.5    Pacific shall have exercised the option agreement
          between BTI and Pacific and issued Pacific Common Stock upon exercise
          thereof.
          
               1.10.6      Such other closing conditions as are customary in a
          transaction of this type.
          
          1.11 EXPENSES. The definitive agreement will contain provisions
whereby Procept and Pacific shall each bear their own costs if the transaction
is not consummated.  If the transaction is consummated, Procept will discharge
expenses of both parties.

     2.   AGREEMENT NOT TO ENTERTAIN OTHER OFFERS.  In consideration of the
efforts and expenses undertaken by both parties in pursuing the contemplated
Merger and other valuable consideration, the receipt and adequacy of which are
acknowledged, the parties agree as follows:

          2.1  Until November 19, 1998 (or such earlier time as Procept and
Pacific agree to abandon the transactions contemplated by this Letter), neither
Pacific nor Procept nor any of their respective authorized representatives may:


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     (i) directly or indirectly, solicit any proposal relating to the
acquisition by another party of all or any portion of the capital stock of such
company or substantially all of the assets of such company (whether by merger
or otherwise);

     (ii) directly or indirectly, engage in any discussions or negotiations
with any other party regarding any such acquisition, or otherwise encourage or
facilitate any efforts by any other party to engage in such an acquisition; or

     (iii) sell, transfer or dispose of all or any portion of the capital stock
of such company or substantially all of the assets of such company (whether by
merger or otherwise);

PROVIDED HOWEVER, that nothing in the foregoing shall restrict either company
from engaging in discussions with potential collaborative partners, subject to
such company disclosing to the other the identity of the party involved in such
discussions and the general nature thereof; and PROVIDED FURTHER that,
notwithstanding the foregoing, each such company and its authorized
representatives may participate in discussions or negotiations with, provide
information to, and consummate a transaction with, a third party which would
otherwise be prohibited by this section, if (A) such discussions or
negotiations had been commenced prior to the date hereof or if commenced after
the date hereof, were not solicited by or on behalf of such company and (B)
such discussions or negotiations were being continued or initiated after
consultation with and based upon written advice of independent legal counsel
which determined in good faith that such action is necessary for the Board of
Directors of the involved company to comply with its fiduciary duties to its
stockholders under applicable law.

          2.2  In the event that during the period between the date hereof and
November 19, 1998, either Pacific or Procept breaches its obligations under
Section 2.1 or engages in discussions or negotiations with, provides
information to, or consummates a transaction with a third party, which activity
would have been a breach of Section 2.1 but for the second proviso of such
section, then, unless a definitive agreement relating to the Merger is
subsequently executed by the parties hereto, on the earlier of (i) the
consummation of any such transaction with a third party or (ii) December 31,
1998, such company shall pay the other a termination fee in the amount of
$50,000, in immediately available funds to an account designated by the
recipient party.  The parties acknowledge and agree that the provisions for
payment of such a termination fee are included herein in order to induce each
party to enter into this agreement and to reimburse the non-terminating party
for incurring the costs and expenses related to the contemplated Merger.  No
more than one termination fee shall be paid by any party hereunder.  The
parties hereto agree that any termination fee that is paid or due hereunder
shall be deemed to be liquidated damages designed to reasonably compensate the
recipient party for the loss incurred by the terminating party's actions.

          2.3  Any definitive agreement between the parties regarding the
Merger shall include a provision parallel to Sections 2.1 and 2.2 hereof,
provided that (i) the obligations of Section 2.1 shall continue until the
earlier of the closing of the Merger or the termination of such definitive
agreement, and (ii) the termination fee shall be in the amount of $150,000 and
shall be payable in the event of a breach by a party of the definitive Merger
agreement or a


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recommendation by the Board of Directors of a party that such company's 
stockholders approve or accept a transaction with a third party of the type 
described in clause (iii) of Section 2.1.

          3.   INVESTIGATION OF BUSINESS AND OPERATIONS OF PACIFIC. Pending
the preparation, execution and delivery of the definitive agreement and
continuing until the Closing Date or termination of this Letter of Intent (i)
Pacific will cause officers and representatives of Pacific (including without
limitation Pacific's firm of independent certified public accountants) to
furnish access to such books and records of Pacific during normal business
hours as Procept, its representatives or agents, may reasonably request in
connection with its review and investigation of the business and operations,
assets and liabilities of Pacific and the market potential for the Business,
and (ii) Procept will cause its officers and representatives (including without
limitation, Procept's firm of independent certified public accountants) to
furnish access to such books and records of Procept during normal business
hours as Pacific, its representatives or agents, may reasonably request in
connection with the review and investigation by it or the Stockholders of the
business and operations, assets and liabilities of Procept.

     4.   CONFIDENTIALITY.  As provided in the Confidentiality Agreement
between the parties, the existence and the terms of this Letter of Intent and
the transactions contemplated herein shall be maintained in confidence by the
parties hereto.  Except to the extent required by law, all public
announcements, notices or other communications regarding such matters to third
parties shall require the prior approval of Procept and Pacific.

     5.   GENERAL.  This Letter of Intent is executed and shall be governed by,
and construed and enforced (to the extent the Sections are stated herein to be
enforceable) in accordance with, the laws of The Commonwealth of Massachusetts.

     If you determine that the foregoing is satisfactory in principle, we would
appreciate acknowledgment of that determination by the execution and delivery
to us of the enclosed copy of this letter.

     We look forward to your favorable consideration of this letter.

                              Very truly yours,

                              PROCEPT, INC.



                              /s/  John F. Dee
                              ------------------
                              John F. Dee
                              President and Chief Executive Officer


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   The foregoing is agreed to and accepted as of the date first set forth
above.


                              PACIFIC PHARMACEUTICALS, INC.



                              /s/ Dr. H. Laurence Shaw
                              ------------------------
                              Dr. H. Laurence Shaw
                              President and Chief Executive Officer




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