DISTRIBUTION AGREEMENT

                                                               December __, 2001
UBS Warburg LLC 677 Washington Blvd.
Stamford, Connecticut 06901


Ladies and Gentlemen:

     Aphton Corporation, a Delaware corporation (the "Company"), confirms its
agreement with UBS Warburg LLC, as agent ("you" or the "Agent") with respect to
the issuance and sale from time to time by the Company, in the manner and
subject to the terms and conditions described below, up to an aggregate of
1,500,000 shares (the "Maximum Number of Shares") of common stock, $0.001 par
value per share (the "Common Stock"), of the Company. Such shares are
hereinafter collectively referred to as the "Shares." The Shares are described
in the Prospectus referred to below.

     The Company has filed with the Securities and Exchange Commission (the
"Commission") a registration statement on Form S-3 (No. 333-72964) for the
registration of at least the Maximum Number of Shares, under the Securities Act
of 1933, as amended, and the rules and regulations of the Commission thereunder
(collectively, the "Act"), and the offering of the Shares from time to time in
accordance with Rule 415 under the Act, and the Company has filed such
post-effective amendments thereto as may be required prior to any sale of Shares
by the Company. Such registration statement (as so amended, if applicable) has
been declared effective by the Commission and is referred to herein as the
"Registration Statement." The final prospectus and all applicable amendments or
supplements thereto (including any pricing supplements relating to the sale of
Shares from time to time), in the form first furnished to the Agent, are
collectively referred to herein as the "Prospectus." All references to the
"Registration Statement" and the "Prospectus" also shall be deemed to include
all documents incorporated therein by reference pursuant to the Securities
Exchange Act of 1934, as amended (the "1934 Act"), prior to any delivery by the
Company of any Purchase Notice (as defined herein); provided, that if the
Company files a registration statement with the Commission pursuant to Rule
462(b) under the Act (the "Rule 462(b) Registration Statement"), then, after
such filing, all references to the "Registration Statement" also shall be deemed
to include the Rule 462(b) Registration Statement. A "preliminary prospectus"
shall be deemed to refer to any prospectus used before the registration
statement became effective and any prospectus furnished by the Company after the
registration statement became effective and prior to any delivery by the Company
of any Purchase Notice which omitted information to be included in a form of
prospectus filed with the Commission pursuant to Rule 424(b) under the Act. For
purposes of this Agreement, all references to the Registration Statement,
Prospectus or preliminary prospectus or to any amendment or supplement thereto
shall be deemed to include any copy filed with the Commission pursuant to its
Electronic Data Gathering, Analysis and Retrieval system ("EDGAR").

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   The Company and the Agent agree as follows:

1. Issuance and Sale.

   (a) Upon the basis of the representations and warranties and subject to the
       terms and conditions herein set forth on any Exchange Business Day (as
       defined below) selected by the Company from the date hereof until the
       earlier of (i) January 21, 2002, and (ii) the termination of this
       Agreement pursuant to Section 9 or 10 (the "Termination Date") (the
       period beginning on the date hereof and ending on the earlier of such
       dates, the "Commitment Period"), (A) with respect to purchases by Agent
       as principal, the Company shall sell to the Agent, and the Agent agrees
       to purchase from the Company, the number of Shares determined in the
       manner and on the terms set forth herein, and (B) with respect to
       purchases by Agent as agent, the Agent and the Company shall enter into
       an agreement regarding the issuance and sale of the number of Shares
       determined in the manner and on the terms set forth below. The Commitment
       Period may be extended until [April 20, 2002] upon the Agent's delivery
       to the Company of a written notice on any date prior to January 7, 2002
       to that effect and the Company's acceptance of such request, provided
       that such extension is contingent upon the Company providing the Agent
       with any due diligence materials and information requested by the Agent
       necessary for the Agent to satisfy its due diligence obligations, and
       satisfaction of the other terms and conditions set forth herein.

   (b) Subject to the terms and conditions set forth below, the Company appoints
       you as Agent in connection with the offer and sale of Shares. In the case
       of sales of Blocks (as defined below), the Agent agrees, as agent of the
       Company, to use its best efforts when requested in the manner described
       herein to solicit offers to purchase the Shares upon the terms and
       conditions set forth in the Prospectus and as agreed to with the Company.
       Each of the Agent and the Company agrees to perform the respective
       agreements specifically provided to be performed by it herein. The
       Company and the Agent agree that any Shares, the placement of which the
       Agent arranges, shall be placed by such Agent in reliance on the
       representations, warranties, covenants and agreements of the Company
       contained herein and shall be subject to the terms and conditions set
       forth herein. The Agent shall not have any obligation whatsoever to
       purchase Blocks from the Company as principal, but the Agent and the
       Company may agree expressly from time to time that the Agent shall
       purchase the Blocks as principal on terms and conditions to be agreed.

   (c) Following delivery of a Purchase Notice (as defined below), the Agent
       will communicate to the Company, orally, each offer to purchase Blocks
       solicited by such Agent on an agency basis. The Agent shall have the
       right, in its sole discretion, reasonably exercised, to reject any
       proposed purchase of Blocks, as a whole or in part, by persons solicited
       by the Agent and any such rejection shall not be deemed a breach of the
       Agreement contained herein. The Company may accept or reject any proposed
       purchase of the Blocks, in whole or in part, and any such rejection shall
       not be deemed a breach of the Company's agreement herein.

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   (d) The Agent shall make reasonable efforts to assist the Company in
       obtaining performance by each purchaser whose offer to purchase Blocks
       has been solicited by the Agent and accepted by the Company. If the
       Company shall default on its obligation to deliver Blocks to a purchaser
       whose offer it has accepted, the Company shall (i) hold the Agent
       harmless against any loss, claim or damage arising from or as a result of
       such default by the Company and (ii) notwithstanding such default, pay to
       such Agent any fee to which it would otherwise be entitled in connection
       with such sale.

2. Purchases as Principal.

   (a) All purchases of Shares, other than purchases of Blocks, unless otherwise
       expressly agreed, shall be purchased by the Agent as principal. In the
       absence of a separate written agreement, the Agent's commitment to
       purchase Shares as principal shall be deemed to have been made on the
       basis of the representations, warranties and covenants contained herein
       and shall be subject to the terms and conditions set forth herein.

   (b) For purchases as principal (other than Blocks), the Company shall sell to
       the Agent, and the Agent agrees to purchase from the Company, the number
       of Shares determined in the manner and on the terms set forth below. The
       Agent intends to resell the Shares purchased under this Agreement in
       transactions and at prices related to the prevailing market price of the
       Common Stock or in such other manner as may be provided in the Prospectus
       and may engage in sales of Common Stock, including short sales, in
       advance of or on the Purchase Date for any Shares deliverable pursuant to
       a Purchase Notice.

3.  Delivery of Purchase Notices.

   (a) The Company may exercise its right to sell Shares (including Blocks)
       hereunder by delivering (in accordance with Section 12 hereof) on any
       Exchange Business Day (as defined below) a written notice to the Agent of
       its election to sell Shares (each such notice, a "Purchase Notice"). Each
       Purchase Notice shall specify:

      (i) whether such Shares shall be sold through the Agent acting as
          principal or whether the Company and the Agent have expressly agreed
          that the Company shall sell such shares to the Agent acting as agent;

     (ii) the number of Shares that the Company intends to sell (the "Specified
          Number of Shares"), which shall be no less than 5% and no more than
          20% of the average daily trading volume in the Common Stock on the
          Exchange for the thirty (30) Exchange Business Days preceding the date
          of delivery of the Purchase Notice, except as otherwise agreed in
          writing by the Agent in its sole discretion;

    (iii) whether the Company will grant the Agent the right to elect to
          purchase additional Shares in accordance with subsection (c) below;
          and

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     (iv) in the case of a purchase of Shares by the Agent acting as principal,
          whether the Company elects to give the Agent the option to increase
          the number of Shares to be sold by the Company and purchased by the
          Agent acting as principal on such Purchase Date.

          A Purchase Notice shall not set forth a Specified Number of Shares
          that, when added to the aggregate number of Shares previously
          purchased and to be purchased pursuant to pending Purchase Notices (if
          any) hereunder, results in a total that exceeds the Maximum Number of
          Shares. The Company shall have responsibility for maintaining records
          with respect to the aggregate principal amount of Shares sold, or for
          otherwise monitoring the availability of Shares for sale under the
          Registration Statement. The Company may deliver only one Purchase
          Notice with respect to any Purchase Date. A Purchase Notice conforming
          to the foregoing requirements, once given, shall be irrevocable, and
          the Company shall be obligated to sell the Specified Number of Shares
          (subject to increase pursuant to paragraph (c) below) and the Agent
          shall be obligated, subject to the satisfaction of the conditions set
          forth in this Agreement, to (x) in case of sales by the Agent acting
          as agent, use its reasonable best efforts to solicit offers for the
          Shares, and (y) in case of purchases by the Agent acting as principal,
          purchase such Shares in accordance with the Purchase Notice.

   (b) The "Purchase Date" in respect of the Shares deliverable pursuant to any
       Purchase Notice shall be the Exchange Business Day next following the day
       on which such Purchase Notice is delivered; provided that if a Purchase
       Notice is delivered prior to 8:30 a.m. (New York time) on an Exchange
       Business Day, the Purchase Date in respect of such Shares shall be such
       date of delivery. For sales and purchases which the Agent undertakes as
       principal, the price per Share for the sale and purchase of any such
       Shares pursuant to this Agreement shall be equal to the volume weighted
       average price per share at which shares of the Common Stock traded on the
       Exchange during regular trading hours on the Purchase Date, as reported
       on the Nasdaq National Market System (the "Gross Sale Price"), less the
       Agent's commission of (i) 5 1/4% of the Gross Sale Price for all Shares
       sold and purchased as principal on such Purchase Date, if the Company
       shall have granted, and the Agent shall have exercised in whole or in
       part, an option pursuant to paragraph (c) below to increase the number of
       Shares sold and purchased as principal on such Purchase Date, or (ii) 6%
       of the Gross Sale Price, in any other case (the Gross Sale Price less the
       Agent's commission is referred to herein as the "Net Sale Price"). For
       sales and purchases of Blocks that the Agent undertakes on a principal
       basis, the price per Share and the commission shall be agreed upon
       between the Company and the Agent on the date of delivery of the Purchase
       Notice.

   (c) If the Company shall have so specified in a Notice of Purchase, which
       relates to a sale to the Agent acting as principal, delivered in respect
       of a Purchase Date, the Agent will have the option to elect, by notice to
       the Company delivered not later than 4:30 p.m. (New York time) on such
       Purchase Date, to increase the number of

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       Shares to be sold by the Company and purchased by the Agent acting as
       principal on such Purchase Date, provided that such number of Shares to
       be sold by the Company shall not exceed two times the Specified Number of
       Shares; and provided further that such number of Shares to be sold by the
       Company, when added to the aggregate number of Shares previously
       purchased and to be purchased pursuant to pending Purchase Notices (if
       any) hereunder, shall not exceed the Maximum Number of Shares. The
       Specified Number of Shares to be sold by the Company on any Purchase
       Date, as it may be increased pursuant to this paragraph (c), is
       hereinafter referred to as the "Purchased Number of Shares" in respect of
       such Purchase Date.

   (d) If the Purchased Number of Shares for any Purchase Date exceeds 50% of
       the total number of shares of Common Stock traded on the Exchange during
       regular trading hours on the Purchase Date, the Purchased Number shall be
       reduced to 50% of such total number of shares traded unless, in its sole
       discretion, the Agent waives this condition in writing as to any Purchase
       Date.

   (e) As used herein:

       "Block" means, as more fully defined in Rule 10b-18 promulgated under the
       1934 Act, a quantity of stock that either (i) has a purchase price of
       $200,000 or more; or (ii) is at least 5,000 shares and has a purchase
       price of at least $50,000; or (iii) is at least 20 round lots of the
       security and totals 150 percent or more of the trading volume for that
       security or, in the event that trading volume data are unavailable, is at
       least 20 round lots of the security and totals at least 1/10th of one
       percent (.001) of the outstanding shares of the security, exclusive of
       any shares owned by an affiliate; provided, however, that a block under
       subsection (i), (ii) and (iii) of this paragraph shall not include any
       amount that a broker or a dealer, acting as principal, has accumulated
       for the purpose of sale or resale to the issuer or to any affiliated
       purchaser of the issuer if the issuer or such affiliated purchaser knows
       or has reason to know that such amount was accumulated for such purpose,
       nor shall it include any amount that a broker or dealer has sold short to
       the issuer or to any affiliated purchaser of the issuer if the issuer or
       such affiliated purchaser knows or has reason to know that the sale was a
       short sale.

       "Exchange Business Day" means any day that is a trading day for the
       Exchange other than a day on which trading on the Exchange is scheduled
       to close prior to its regular weekday closing time,

       "Exchange" means the Nasdaq National Market System, and

   (f) Payment of the purchase price for Shares sold by the Company on any
       Purchase Date pursuant to a Purchase Notice shall be made to the Company
       by federal funds wire transfer to account number ________________ against
       delivery of such Shares to: (x) the accounts specified in writing by the
       Agent for sales made by the Agent acting as agent, or (y) the Agent
       through the facilities of the Depository Trust Company for purchase from
       the Company by the Agent acting as principal.

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       Such payment and delivery shall be made at or about 10:00 a.m., local
       time in New York, New York, on the third Exchange Business Day following
       each Purchase Date (the "Closing Date"). If the Company fails for any
       reason to make timely delivery of such Shares, the Company shall
       indemnify the Agent and its successors and assigns and hold them harmless
       from and against any loss, damage, expense, liability or claim that the
       Agent may incur as a result of such failure.

   4. Representations and Warranties of the Company. The Company represents and
warrants to the Agent, on and as of (i) the date hereof, (ii) each date on which
the Company delivers a Purchase Notice to the Agent, (iii) each Purchase Date,
(iv) each Closing Date, and (v) each date on which the Registration Statement or
the Prospectus is amended or supplemented or there is filed by the Company with
the Commission any document incorporated by reference into the Prospectus (other
than any Current Report on Form 8-K relating exclusively to the issuance of
Shares under the Registration Statement)(each such date listed in (i) through
(v), a "Representation Date") that:

   (a) the Company meets the requirements for use of Form S-3 under the Act; the
       Registration Statement (including any Rule 462(b) Registration Statement)
       has become effective under the Act and no stop order suspending the
       effectiveness of the Registration Statement (including any Rule 462(b)
       Registration Statement) has been issued under the Act and no proceedings
       for that purpose have been instituted or are pending or, to the Company's
       knowledge, are threatened by the Commission, and any request on the part
       of the Commission for additional information has been complied with; the
       Registration Statement (including any Rule 462(b) Registration Statement)
       and any amendments thereto (including the filing of the Company's most
       recent Annual Report on Form 10-K with the Commission (the "Annual Report
       on Form 10-K")) comply in all material respects with the requirements of
       the Act and do not contain an untrue statement of a material fact or omit
       to state a material fact required to be stated therein or necessary to
       make the statements therein not misleading; each preliminary prospectus
       and prospectus filed as part of the Registration Statement as originally
       filed or as part of any amendment thereto, or filed pursuant to Rule 424
       under the Act, complied when so filed in all material respects with the
       Act; each preliminary prospectus and the Prospectus delivered to the
       Agent for use in connection with the offering of Shares are identical to
       any electronically transmitted copies thereof filed with the Commission
       pursuant to EDGAR, except to the extent permitted by Regulation S-T; and
       neither the Prospectus nor any amendment or supplement thereto includes
       an untrue statement of a material fact or omits to state a material fact
       necessary in order to make the statements therein, in the light of the
       circumstances under which they were made, not misleading; provided,
       however, that the representations and warranties in this subsection shall
       not apply to statements in or omissions from the Registration Statement
       or the Prospectus made in reliance upon and in conformity with
       information furnished to the Company in writing by the Agent expressly
       for use in the Registration Statement or the Prospectus;

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   (b) the documents incorporated or deemed to be incorporated by reference in
       the Prospectus, at the time they were or hereafter are filed with the
       Commission, complied and will comply in all material respects with the
       requirements of the 1934 Act and, when read together with the other
       information in the Prospectus, at the date of the Prospectus and at each
       Representation Date, did not and will not include an untrue statement of
       a material fact or omit to state a material fact necessary in order to
       make the statements therein, in the light of the circumstances under
       which they were made, not misleading;

   (c) as of the date of this Agreement the Company has, and as of each
       Representation Date the Company will have, an authorized capitalization
       as set forth in the Registration Statement and the Prospectus; all of the
       issued and outstanding shares of capital stock of the Company and the
       Subsidiaries (as defined below), including the Common Stock, and to the
       Company's knowledge, after due inquiry, have been duly and validly
       authorized and issued and are fully paid and non-assessable, have been
       issued in compliance with all applicable laws (including, but not limited
       to, federal and state securities laws) and were not issued in violation
       of any preemptive right, resale right, right of first refusal or similar
       right;

   (d) the Maximum Number of Shares is less than 10% of the aggregate market
       value of the Company's outstanding voting stock held by non-affiliates of
       the Company (calculated as of a date within 60 days prior to the date of
       the filing of the Registration Statement);

   (e) except as disclosed in the Registration Statement, each of the Company
       and each subsidiary of the Company set forth on Schedule I hereto (each a
       "Subsidiary" and, collectively, the "Subsidiaries") has been duly
       incorporated and is validly existing as a corporation and is in good
       standing under the laws of its respective jurisdiction of incorporation
       with all requisite corporate power and authority to own, lease and
       operate its respective properties and to conduct its respective business
       as conducted and as proposed to be conducted as described in the
       Registration Statement and Prospectus;

   (f) each of the Company and the Subsidiaries is duly qualified or registered
       to do business as a foreign corporation in good standing in each
       jurisdiction in which it conducts its respective business as conducted,
       and as proposed to be conducted as described in the Registration
       Statement and Prospectus, where the ownership or leasing of its
       properties or the conduct of its business requires such qualification,
       except where the failure to so qualify, individually or in the aggregate,
       would not have a material adverse effect on the business, prospects,
       properties, financial condition or results of operation of the Company
       and the Subsidiaries, taken as a whole (a "Material Adverse Effect");

   (g) the Company has no significant subsidiaries (as defined in Rule 1-02 of
       Regulation S-X under the Act) other than the Subsidiaries; other than the
       Subsidiaries the Company does not own, directly or indirectly, any shares
       of stock or any other

                                      - 7 -
<PAGE>

       equity or long-term debt securities of any corporation or have any equity
       interest in any firm, partnership, joint venture, association or other
       entity;

   (h) complete and correct copies of the certificates of incorporation and of
       the bylaws of the Company and the Subsidiaries and all amendments thereto
       have been delivered to you or included in the Registration Statement, and
       except as set forth in the Registration Statement no changes therein will
       be made during the term of this agreement;

   (i) except as disclosed in the Registration Statement, all of the outstanding
       shares of capital stock of each of the Subsidiaries have been duly
       authorized and validly issued, are fully paid and non-assessable and
       (except as otherwise described in this Section 4(i)) are owned by the
       Company subject to no security interest, other encumbrance or adverse
       claims; no options, warrants or other rights to purchase, agreements or
       other obligations to issue or other rights to convert any obligation into
       shares of capital stock or ownership interests in the Subsidiaries are
       outstanding;

   (j) except as disclosed in the Registration Statement, the Company and each
       of the Subsidiaries are in compliance in all material respects with all
       applicable laws, orders, rules, regulations, directives, decrees and
       judgments;

   (k) except as disclosed in the Registration Statement, neither the Company
       nor any of the Subsidiaries is in breach of, or in default (nor has any
       event occurred which with notice, lapse of time, or both would result in
       any breach of, or constitute a default under), under (a) its respective
       certificate of incorporation, charter or by-laws or (b) in the
       performance or observance of any obligation, agreement, covenant or
       condition contained in any license, indenture, mortgage, deed of trust,
       bank loan or credit agreement or other evidence of indebtedness, or any
       lease, contract or other agreement or instrument to which the Company or
       any of the Subsidiaries is a party or by which any of them or any of
       their properties is bound, except in the case of clause (b), for such
       breaches or defaults as would not reasonably be expected to have a
       Material Adverse Effect, and the execution, delivery and performance of
       this Agreement, the issuance and sale of the Shares and the consummation
       of the transactions contemplated hereby will not conflict with, or result
       in any breach of or constitute a default under (nor constitute any event
       which with notice, lapse of time, or both would result in any breach of,
       or constitute a default under) (i) any provision of the articles of
       incorporation, charter or by-laws of the Company or any of the
       Subsidiaries, or (ii) any provision of any license, indenture, mortgage,
       deed of trust, bank loan or credit agreement or other evidence of
       indebtedness, or any lease, contract or other agreement or instrument to
       which the Company or any of the Subsidiaries is a party or by which any
       of them or their respective properties may be bound or affected, or (iii)
       any federal, state, local or foreign law, regulation or rule or any
       decree, judgment or order applicable to the Company or any of the
       Subsidiaries, except in the case of clauses (ii) and (iii) for such
       conflicts, breaches, or defaults, individually or in the aggregate, as
       would not reasonably be expected to have a Material Adverse Effect;

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   (l) the Company has full legal right, power and authority to enter into and
       perform this Agreement and to consummate the transactions contemplated
       herein; this Agreement has been duly authorized, executed and delivered
       by the Company and is a legal, valid and binding agreement of the Company
       enforceable in accordance with its terms, except (i) as may be limited by
       bankruptcy, insolvency, reorganization, moratorium or similar laws
       affecting creditors' rights generally, or (ii) as any rights to indemnity
       or contribution hereunder may be limited by federal and state securities
       laws and public policy considerations;

   (m) the capital stock of the Company, including the Shares, conforms in all
       material respects to the description thereof contained in the
       Registration Statement and Prospectus, and the certificates for the
       Shares (to the extent such Shares are certificated) are in due and proper
       form;

   (n) the issuance and sale of the Shares through or to the Agent hereunder
       have been duly authorized by the Company; when issued and delivered
       against payment therefor as provided in this Agreement, the Shares will
       be validly issued, fully paid and non-assessable and the issuance of the
       Shares will not be subject to any preemptive or similar rights; no person
       or entity holds a right to require or participate in the registration
       under the Act of the Shares pursuant to the Registration Statement; no
       person or entity has a right of participation or first refusal with
       respect to the sale of the Shares by the Company;

   (o) there are no contracts, agreements or understandings between the Company
       or its Subsidiaries and any person or entity granting such person or
       entity the right, contractual or otherwise, to cause the Company to issue
       to it, or register pursuant to the Act, any securities or shares of
       capital stock of the Company upon the issue and sale of the Shares to the
       Agent hereunder, or to require the Company to include such securities
       with the Shares registered pursuant to the Registration Statement, nor
       does any person have preemptive rights, co-sale rights, rights of first
       refusal or other rights to purchase any of the Shares other than those
       that have been expressly waived before the date hereof;

   (p) the form of certificates evidencing the Shares (to the extent such Shares
       are certificated) complies with all applicable legal requirements and, in
       all material respects, with all applicable requirements of the charter
       and bylaws of the Company and the requirements of the NASD;

   (q) no approval, authorization, consent or order of or filing with any
       federal, state or local governmental or regulatory commission, board,
       body, authority or agency is required in connection with (i) the
       execution, delivery and performance by the Company of this Agreement and
       the consummation of the transactions contemplated hereby or (ii) the sale
       and delivery of the Shares, other than (x) such as have been obtained, or
       will have been obtained on the relevant Closing Date under the Act or the
       1934 Act, (y) such approvals as have been obtained in connection with the
       approval of the listing of the Shares on the Nasdaq National Market
       System and (z) any necessary qualification under the securities or blue
       sky

                                      - 9 -
<PAGE>

       laws of the various jurisdictions in which the Shares are being offered
       by the Agent;

   (r) Ernst & Young LLP, whose report on the consolidated financial statements
       of the Company and the Subsidiaries is filed with the Commission as part
       of the Registration Statement and Prospectus, are and were during the
       periods covered by their reports independent public accountants as
       required by the Act;

   (s) each of the Company and the Subsidiaries has all necessary licenses,
       authorizations, consents and approvals and has made all necessary filings
       required under any federal, state, local or foreign law, regulation or
       rule, and has obtained all necessary authorizations, consents and
       approvals from other persons, in order to conduct its respective
       business, unless the failure to possess such licenses, authorizations,
       consents and other governmental or regulatory authorizations and
       approvals, individually or in the aggregate, could not reasonably be
       expected to have Material Adverse Effect; neither the Company nor any of
       the Subsidiaries is in violation of, in default under or has received any
       notice regarding a possible violation, default or revocation of any such
       license, authorization, consent or approval or any federal, state, local
       or foreign law, regulation or rule or any decree, order or judgment
       applicable to the Company or any of the Subsidiaries the effect of which
       could reasonably be expected to have a Material Adverse Effect;

   (t) the Prospectus in paper format delivered to the Agent for use in
       connection with this offering will be identical in all material respects
       to the version of the Prospectus created to be transmitted to the
       Commission for filing via EDGAR, except to the extent permitted by
       Regulation S-T;

   (u) all legal or governmental proceedings, contracts, leases or documents of
       a character required to be described in the Registration Statement or the
       Prospectus or to be filed as an exhibit to the Registration Statement
       have been so described or filed as required;

   (v) except as disclosed in the Registration Statement, there are no legal or
       governmental proceedings pending or threatened to which the Company or
       any of the Subsidiaries or any of their respective officers is a party or
       of which any of their respective properties is subject at law or in
       equity, or before or by any federal, state, local or foreign governmental
       or regulatory commission, which, if determined adversely to the Company
       or any of its Subsidiaries, could result in a judgment, decree or order
       which could reasonably be expected to have a Material Adverse Effect or
       prevent consummation of the transactions contemplated hereby;

   (w) the consolidated financial statements of the Company and the Subsidiaries
       included in the Registration Statement and the Prospectus present fairly
       in all material respects the consolidated financial position of the
       Company and the Subsidiaries as of the dates indicated and the
       consolidated results of operations and cash flows of the Company and the
       Subsidiaries for the periods specified; such financial statements have
       been prepared in conformity with generally accepted

                                     - 10 -
<PAGE>

       accounting principles as applied in the United States and on a consistent
       basis during the periods involved and in accordance with Regulation S-X
       promulgated by the Commission; the financial statement schedules included
       or incorporated by reference in the Registration Statement and the
       Prospectus fairly present in all material respects the information
       required to be shown therein; no other financial statements or schedules
       are required by Form S-3 or otherwise to be included in the Registration
       Statement or Prospectus; any pro forma financial statements and other pro
       forma financial information included in the Registration Statement and
       the Prospectus present fairly the information shown therein, have been
       prepared in accordance with the Commission's rules and guidelines for pro
       forma financial statements, have been properly compiled on the pro forma
       bases set forth therein and, in the opinion of the Company, the
       assumptions used in the preparation thereof are reasonable and the
       adjustments used therein are appropriate to reflect the transaction or
       circumstances referred to therein;

   (x) subsequent to the respective dates as of which information is given in
       the Registration Statement and the Prospectus, there has not been (i) any
       material adverse change, or any development involving a prospective
       material adverse change, in the business, prospects, properties or assets
       described or referred to in the Registration Statement, or the results of
       operations, condition (financial or otherwise), business or operations of
       the Company and the Subsidiaries, whether or not arising in the ordinary
       course of business, or (ii) any transaction which is material to the
       Company or the Subsidiaries, planned or entered into by the Company or
       any of the Subsidiaries, or (iii) any obligation, direct or contingent,
       which is material to the Company and the Subsidiaries, incurred by the
       Company or the Subsidiaries, except obligations incurred in the ordinary
       course of business, or (iv) any change in the capital stock or
       outstanding indebtedness of the Company or the Subsidiaries, or (v) any
       dividend or distribution of any kind declared, paid or made on the
       capital stock of the Company. Neither the Company nor the Subsidiaries
       has any material contingent obligation which is not disclosed in the
       Registration Statement;

   (y) the Company has filed in a timely manner all reports required to be filed
       pursuant to Sections 13, 14, 15(d) of the 1934 Act during the preceding
       twelve calendar months and if during such period the Company has relied
       on Rule 12b-25(b) under the 1934 Act ("Rule 12b-25(b)") with respect to a
       report or a portion of a report, that report or portion of a report has
       actually been filed within the time period prescribed by Rule 12b-25(b);

   (z) the Company is not and, after giving effect to the offering and sale of
       the Shares, will not be an "investment company" or an entity "controlled"
       by an "investment company," as such terms are defined in the Investment
       Company Act of 1940, as amended (the "Investment Company Act");

  (aa) except as disclosed in the Prospectus or on Schedule 4(aa), there are no
       outstanding (i) securities or obligations of the Company or any of its
       Subsidiaries convertible into or exchangeable for any capital stock of
       the Company or any such
                                     - 11 -
<PAGE>




       Subsidiary, or (ii) warrants, rights or options to subscribe for or
       purchase from the Company or any such Subsidiary any such capital stock
       or any such convertible or exchangeable securities or obligations, or
       (iii) obligations of the Company or any such Subsidiary to issue any
       shares of capital stock, any such convertible or exchangeable securities
       or obligation, or any such warrants, rights or options;

  (bb) each of the Company, the Subsidiaries, and each of their respective
       officers, directors and controlling persons has not taken, and will not
       take, directly or indirectly, any action which is designed to or which
       has constituted or which might reasonably be expected to cause or result
       in stabilization or manipulation of the price of any security of the
       Company to facilitate the sale or resale of the Shares;

  (cc) the Company (i) is not required to register as a "broker" or "dealer" in
       accordance with the provisions of the 1934 Act or the rules and
       regulations thereunder, and (ii) directly, or indirectly through one or
       more intermediaries, does not control any member firm of the NASD;

  (dd) the Company has not relied upon the Agent or legal counsel for the Agent
       for any legal, tax or accounting advice in connection with the offering
       and sale of the Shares;

  (ee) any certificate signed by any officer of the Company or any Subsidiary
       delivered to the Agent or to counsel for the Agent pursuant to or in
       connection with this Agreement shall be deemed a representation and
       warranty by the Company to the Agent as to the matters covered thereby;

  (ff) to the Company's knowledge, all agreements between the Company or any of
       the Subsidiaries and third parties expressly referenced in the Prospectus
       are legal, valid and binding obligations of the Company or one or more of
       the Subsidiaries, enforceable in accordance with their respective terms,
       except to the extent enforceability may be limited by bankruptcy,
       insolvency, reorganization, moratorium or similar laws affecting
       creditors' rights generally and by general principles of equity;

  (gg) no relationship, direct or indirect, exists between or among the Company
       or any of the Subsidiaries, on the one hand, and the directors, officers,
       stockholders, customers or suppliers of the Company or any of the
       Subsidiaries, on the other hand, which is required by the Act to be
       described in the Registration Statement and the Prospectus that is not so
       described;

  (hh) with such exceptions as could not reasonably be expected to have a
       Material Adverse Effect on the Company and the Subsidiaries, taken as a
       whole, the Company and the Subsidiaries have good and marketable title in
       fee simple to all real property, if any, and good title to all personal
       property owned by them, in each case free and clear of all liens,
       security interests, pledges, charges, encumbrances, mortgages and
       defects, except such as are disclosed in the Prospectus or such as do not
       materially and adversely affect the value of such property and do not
       interfere

                                     - 12 -
<PAGE>

       with the use made or proposed to be made of such property by the Company
       and the Subsidiaries; and any real property and buildings held under
       lease by the Company or any Subsidiary are held under valid, existing and
       enforceable leases, with such exceptions as are disclosed in the
       Prospectus or are not material and do not interfere with the use made or
       proposed to be made of such property and buildings by the Company or such
       Subsidiary;

  (ii) the Company and the Subsidiaries have ownership or license or legal right
       to use all material patent, copyright, trade secret and trademark rights
       known by it to be necessary to the conduct of the business of the Company
       and the Subsidiaries as now conducted (collectively, "Intellectual
       Property") other than Intellectual Property generally available on
       commercial terms from other sources;

  (jj) all material licenses or other material agreements under which (i) the
       Company and the Subsidiaries are granted rights in Intellectual Property,
       other than Intellectual Property generally available on commercial terms
       from other sources, and (ii) the Company or any Subsidiary has granted
       rights to others in Intellectual Property owned or licensed by the
       Company or the Subsidiaries, are in full force and effect and there is no
       material default by the Company or any Subsidiary or, to the Company's
       knowledge, any other party thereto;

  (kk) each of the Company and the Subsidiaries have taken all reasonable steps
       required in accordance with sound business practice and business judgment
       to establish and preserve its ownership of all material copyright, trade
       secret and other proprietary rights with respect to its products and
       technology;

  (ll) to the Company's knowledge, after due inquiry, the present business,
       activities and products of the Company and the Subsidiaries do not
       infringe any Intellectual Property of any other person, except where such
       infringement would not, individually or in the aggregate, have a Material
       Adverse Effect on the Company. Except as described in documents filed
       with the Commission, to the Company's knowledge, no proceeding charging
       the Company or any Subsidiary with infringement of any adversely held
       Intellectual Property has been filed; the Company and the Subsidiaries
       are not making unauthorized use of any confidential information or trade
       secrets obtained by the Company or its Subsidiaries from any other
       person; the activities of each of the Company or the Subsidiaries or any
       of its employees on behalf of the Company or any Subsidiary do not
       violate any agreements or arrangements known to the Company or any
       Subsidiary which any such employees have with other persons, if any;

  (mm) the Company and each of its Subsidiaries maintain a system of internal
       accounting controls sufficient to provide reasonable assurance that (i)
       transactions are executed in accordance with management's general or
       specific authorizations; (ii) transactions are recorded as necessary to
       permit preparation of financial statements in conformity with generally
       accepted accounting principles as applied in the United States and to
       maintain asset accountability; (iii) access to assets is permitted only
       in accordance with management's general or specific authorization;

                                     - 13 -
<PAGE>

       and (iv) the recorded accountability for assets is compared with the
       existing assets at reasonable intervals and appropriate action is taken
       with respect to any differences;

  (nn) each of the Company and the Subsidiaries have filed on a timely basis all
       material federal, state, local and foreign income and franchise tax
       returns required to be filed through the date hereof and have paid all
       taxes shown as due thereon; and no tax deficiency has been asserted
       against any such entity, nor does any such entity know of any tax
       deficiency which is likely to be asserted against any such entity which
       if, determined adversely to any such entity, could have a Material
       Adverse Effect; all tax liabilities are adequately provided for on the
       respective books of such entities;

  (oo) neither the Company nor any of the Subsidiaries nor, to the best of the
       Company's knowledge, any agent, officer or director purporting to act on
       behalf of the Company or any of the Subsidiaries has at any time; (i)
       made any contributions to any candidate for political office, or failed
       to disclose fully any such contributions, in violation of law, or (ii)
       made any payment to any state, federal or foreign governmental officer or
       official, or other person charged with similar public or quasi-public
       duties, other than payments required or allowed by applicable law, or
       (iii) received or retained any funds in violation of law or of a
       character required to be disclosed in the Prospectus;

  (pp) the Shares have been approved for listing, upon official notice of
       issuance, on the Nasdaq National Market System;

  (qq) in connection with this offering, the Company has not offered and will
       not offer shares of its Common Stock or any other securities convertible
       into or exchangeable or exercisable for shares of Common Stock in a
       manner in violation of the Act; the Company has not distributed and will
       not distribute any offering material in connection with the offer and
       sale of the Shares, other than the Prospectus, Registration Statement and
       other materials permitted by the Act; and

  (rr) the Company has not incurred any liability for any finder's fees or
       similar payments in connection with the transactions herein contemplated.

5. Certain Covenants of the Company.  The Company hereby agrees with the Agent:

   (a) before amending or supplementing the Registration Statement or the
       Prospectus, or, during any period of time in which a Prospectus relating
       to the Shares is required to be delivered under the Act, to furnish to
       the Agent a copy of each such proposed amendment or supplement before
       filing any such amendment or supplement with the Commission;

   (b) to make no post-effective amendment or supplement to the Registration
       Statement or the Prospectus which shall have been disapproved by the
       Agent by notice in

                                     - 14 -
<PAGE>

       writing to the Company after notice thereof and reasonable opportunity to
       review and comment thereon;

   (c) to prepare, with respect to any Shares sold by the Company to the Agent
       pursuant to this Agreement, a Pricing Supplement with respect to such
       Shares in a form previously approved by the Agent and to file such
       Pricing Supplement pursuant to Rule 424(b) under the Act not later than
       the close of business of the Commission on the third business day after
       any Purchase Date on which an aggregate of __% or more of the Shares were
       sold, and provide each such Pricing Supplement to the Agent at the same
       time;

   (d) to file promptly all reports and any definitive proxy or information
       statements required to be filed by the Company with the Commission
       pursuant to Sections 13(a), 13(c), 14 or 15(d) of the 1934 Act for so
       long as the delivery of a Prospectus is required in connection with the
       offering or sale of the Shares, and during such same period to advise the
       Agent, promptly after the Company receives notice thereof, of the time
       when any amendment to the Registration Statement has been filed or has
       become effective or any supplement to the Prospectus or any amended
       Prospectus has been filed with the Commission, or the issuance by the
       Commission of any stop order or of any order preventing or suspending the
       use of any prospectus relating to the Shares, or the suspension of the
       qualification of the Shares for offering or sale in any jurisdiction, of
       the initiation or threatening of any proceeding for any such purpose, or
       of any request by the Commission for the amendment or supplementation of
       the Registration Statement or Prospectus or for additional information;
       and

   (e) in the event of the issuance of any such stop order or of any such order
       preventing or suspending the use of any such prospectus or suspending any
       such qualification, to use promptly its reasonable best efforts to obtain
       its withdrawal;

   (f) to furnish such information as may be required and otherwise to cooperate
       in qualifying the Shares for offering and sale under the securities or
       blue sky laws of such states as you may reasonably designate and to
       maintain such qualifications in effect so long as required for the
       distribution of the Shares; provided that the Company shall not be
       required to qualify as a foreign corporation, become a dealer of
       securities, or become subject to taxation in, or to consent to the
       service of process under the laws of any such state (except service of
       process with respect to the offering and sale of the Shares); and to
       promptly advise you of the receipt by the Company of any notification
       with respect to the suspension of the qualification of the Shares for
       sale in any jurisdiction or the initiation of any proceeding for such
       purpose;

   (g) to make available to the Agent in Stamford, Connecticut, as soon as
       practicable after the Registration Statement becomes effective, and
       thereafter from time to time to furnish to the Agent, as many copies of
       the Prospectus (or of the Prospectus as amended or supplemented if the
       Company shall have made any amendments or supplements thereto after the
       effective date of the Registration

                                     - 15 -
<PAGE>

       Statement) as the Agent may reasonably request for the purposes
       contemplated by the Act; and for so long as this agreement is in effect,
       the Company will prepare and file promptly, subject to Section 5(b)
       hereof, such amendment or amendments to the Registration Statement and
       the Prospectus as may be necessary to comply with the requirements of
       Section 10(a)(3) of the Act;

   (h) to furnish to you for a period of three years from the date of this
       Agreement (i) copies of any reports or other communications which the
       Company shall send to its stockholders or shall from time to time publish
       or publicly disseminate, (ii) copies of all annual, quarterly and current
       reports filed with the Commission on Forms 10-K, 10-Q and 8-K, or such
       other similar form as may be designated by the Commission, and (iii)
       copies of documents or reports filed with any national securities
       exchange on which any class of securities of the Company is listed, and
       to furnish to you from time to time during the term of this Agreement
       such other information as you may reasonably request regarding the
       Company or the Subsidiaries, in each case as soon as such reports,
       communications, documents or information becomes available;

   (i) if at any time during the term of this Agreement any event shall occur or
       condition exist as a result of which it is necessary, in the reasonable
       opinion of counsel for the Agent or counsel for the Company, to further
       amend or supplement the Prospectus in order that the Prospectus will not
       include an untrue statement of a material fact or omit to state any
       material fact necessary in order to make the statements therein not
       misleading in light of the circumstances existing at the time the
       Prospectus is delivered to a purchaser, or if it shall be necessary, in
       the reasonable opinion of either such counsel, to amend or supplement the
       Registration Statement or the Prospectus in order to comply with the
       requirements of the Act, immediate notice shall be given, and confirmed
       in writing, to the Agent to cease the solicitation of offers to purchase
       the Shares in the Agent's capacity as agent and to cease sales of any
       Shares the Agent may then own as principal, and the Company will promptly
       prepare and file with the Commission such amendment or supplement,
       whether by filing documents pursuant to the Act, the 1934 Act or
       otherwise, as may be necessary to correct such untrue statement or
       omission or to make the Registration Statement and Prospectus comply with
       such requirements;

   (j) to generally make available to its security holders as soon as
       practicable, but not later than 90 days after the close of the period
       covered thereby, an earnings statement (in form complying with the
       provisions of Section 11(a) under the Act) covering each twelve-month
       period beginning, in each case, not later than the first day of the
       Company's fiscal quarter next following the "effective date" (as defined
       in such Rule 158) of the Registration Statement with respect to each sale
       of Shares;

   (k) to furnish to you two signed copies of the Registration Statement, as
       initially filed with the Commission, and of all amendments thereto,
       including all exhibits thereto and all documents incorporated by
       reference therein;

                                     - 16 -
<PAGE>

   (l) to apply the net proceeds from the sale of the Shares in the manner
       set forth under the caption "Use of Proceeds" in the Prospectus;

   (m) to pay all costs, expenses, fees and taxes in connection with (i) the
       preparation and filing of the Registration Statement, each Preliminary
       Prospectus, the Prospectus, and any amendments or supplements thereto,
       and the printing and furnishing of copies of each thereof to the Agent
       and to dealers (including costs of mailing and shipment), (ii) the
       registration, issue, sale and delivery of the Shares, (iii) the
       producing, word processing and/or printing of this Agreement, any powers
       of Attorney and any closing documents (including compilations thereof)
       and the reproduction and/or printing and furnishing of copies of each
       thereof to the Agent (including costs of mailing and shipment), (iv) the
       qualification of the Shares for offering and sale under state laws and
       the determination of their eligibility for investment under state law as
       aforesaid (including the legal fees and filing fees and other
       disbursements of counsel for the Agent) and the printing and furnishing
       of copies of any blue sky surveys or legal investment surveys to the
       Agent, (v) the listing of the Shares on the Exchange and any registration
       thereof under the 1934 Act, (vi) any filing for review of the public
       offering of the Shares by the NASD, including the fees and disbursements
       of counsel to the Agent in connection therewith, (vii) all other fees and
       disbursements of counsel to the Company and counsel to the Agent, and
       (viii) the performance of the Company's other obligations hereunder;
       provided that the Agent shall be responsible for any transfer taxes on
       resale of Shares by it;

   (n) to furnish to you, before filing with the Commission subsequent to the
       effective date of the Registration Statement and during the period
       referred to in paragraph (g) above, a copy of any document proposed to be
       filed pursuant to Section 13, 14 or 15(d) of the 1934 Act;

   (o) to use its reasonable best efforts to cause the Shares to be listed
       on the Exchange; and

   (p) to use its best efforts to satisfy, or cause to be satisfied, the
       conditions set forth below in Section 6 on or in respect of each Closing
       Date hereunder.

     6. Execution of Agreement. The Agent's obligation to execute this Agreement
shall be subject to the satisfaction of the following conditions in connection
with and on the intended date of the execution of this Agreement:

     (a)  the Company shall have delivered to the Agent:

          (i)  an officer's certificate signed by two of its executive officers
               certifying as to the matters set forth in Exhibit A hereto;

          (ii) an opinion of White & Case LLP, counsel for the Company,
               addressed to the Agent and dated the date of this Agreement, in
               the form of Exhibit B hereto, with

                                     - 17 -
<PAGE>

               only such departures from such form as Stroock & Stroock & Lavan
               LLP, counsel for the Agent, shall have approved;

         (iii) an intellectual property opinion of White & Case LLP, addressed
               to the Agent and dated the date of this Agreement, in the form of
               Exhibit C hereto, with only such departures from such form as
               Stroock & Stroock & Lavan LLP, counsel for the Agent, shall have
               approved;

          (iv) a letter of Ernst & Young LLP dated the date of this Agreement
               and addressed to the Agent;

          (v)  evidence reasonably satisfactory to the Agent and its counsel
               that the Registration Statement has become effective;

          (vi) evidence reasonably satisfactory to the Agent and its counsel
               that the Shares have been approved for listing on the Exchange,
               subject only to notice of issuance at or before the time of
               purchase on the relevant Purchase Date; and

         (vii) such other documents as the Agent shall reasonably request; and

     (b)  The Agent shall have received the favorable opinion of Stroock &
          Stroock & Lavan LLP as to the matters set forth in Exhibit E hereto.

     7. Additional Covenants of the Company. The Company further covenants and
agrees with the Agent as follows:

     (a)  Each delivery of a Purchase Notice by the Company to the Agent shall
          be deemed to be an affirmation that the representations and warranties
          of the Company herein contained and contained in any certificate
          delivered to the Agent pursuant hereto are true and correct at the
          time of such delivery, and an undertaking that such representations
          and warranties will be true and correct at the time of the
          consummation of the purchase by the Agent, and at the time of delivery
          to the Agent of Shares pursuant to the Purchase Notice, as though made
          at and as of each such time (it being understood that such
          representations and warranties shall relate to the Registration
          Statement and Prospectus as amended and supplemented to the time of
          such Purchase Notice);

     (b)  Each time that the Registration Statement or the Prospectus shall be
          amended or supplemented (including by the filing of any document
          incorporated by reference therein, but excluding any prospectus
          supplement relating solely to the offering of Shares pursuant to a
          Purchase Notice), the Company shall furnish or cause to be furnished
          to the Agent forthwith a certificate, dated the date of filing with
          the Commission or the date of effectiveness of such amendment or
          supplement, as applicable, in form satisfactory to the Agent, to the
          effect that the statements contained in the certificate referred to in
          Section 6(a)(i) hereof are true and correct in all material respects
          at the time of the filing or effectiveness of such amendment or
          supplement, as applicable, as though made at and as of such time
          (except that

                                     - 18 -
<PAGE>

          such statements shall be deemed to relate to the Registration
          Statement and the Prospectus as amended and supplemented to such time)
          or, in lieu of such certificate, a certificate of the same tenor as
          the certificate referred to Section 6(a)(i) hereof, modified as
          necessary to relate to the Registration Statement and the Prospectus
          as amended and supplemented to the time of delivery of such
          certificate. Any such certificate shall also include a certification
          that there has been no material adverse change in the condition,
          financial or otherwise, or in the earnings, business affairs or
          business prospects of the Company and its subsidiaries considered as
          one enterprise since the date of the last such certificate previously
          delivered to the Agent;

     (c)  Each time that the Registration Statement or the Prospectus shall be
          amended or supplemented (including by the filing of any document
          incorporated by reference therein, but excluding any prospectus
          supplement relating solely to the offering of Shares pursuant to a
          Purchase Notice), the Company shall furnish or cause to be furnished
          forthwith to the Agent and to counsel for the Agent the written
          opinion of White & Case LLP, or other counsel satisfactory to the
          Agent, dated the date of filing with the Commission or the date of
          effectiveness of such amendment or supplement, as applicable, in form
          and substance satisfactory to the Agent, of the same tenor as the
          opinion referred to in Section 6(a)(ii) hereof, but modified as
          necessary to relate to the Registration Statement and the Prospectus
          as amended and supplemented to the time of delivery of such opinion
          or, in lieu of such opinion, counsel last furnishing such opinion to
          the Agent shall furnish the Agent with a letter substantially to the
          effect that the Agent may rely on such last opinion to the same extent
          as though it was dated the date of such letter authorizing reliance
          (except that statements in such last opinion shall be deemed to relate
          to the Registration Statement and the Prospectus as amended and
          supplemented to the time of delivery of such letter authorizing
          reliance);

     (d)  Each time that the Registration Statement or the Prospectus shall be
          amended or supplemented to include additional financial information
          (including by the filing of any document incorporated by reference
          therein), the Company shall cause Ernst & Young LLP immediately to
          furnish to the Agent a letter, dated the date of filing with the
          Commission or the date of effectiveness of such amendment or
          supplement, as applicable, of the same tenor as the letter referred to
          in Section 6(a)(iii) hereof, but modified to relate to the
          Registration Statement and Prospectus as amended and supplemented to
          the date of such letter; and

     (e)  Prior to the date of this Agreement (i) no stop order suspending the
          effectiveness of the Registration Statement or any post-effective
          amendment thereto, and no order directed at any document incorporated
          by reference therein and no order preventing or suspending the use of
          any Prospectus will have been issued by the Commission, and no
          suspension of the qualification of the Shares for offering or sale in
          any jurisdiction, or of the initiation or threatening of any
          proceedings for any of such purposes, will have occurred; and (ii) the
          Registration Statement and the Prospectus shall not contain an untrue
          statement of material fact or omit to

                                     - 19 -
<PAGE>

          state a material fact required to be stated therein or necessary to
          make the statements therein, in the light of the circumstances under
          which they were made, not misleading.

     8. Conditions of Agent's Obligation to Purchase Shares. The Company's right
to deliver a Purchase Notice and the Agent's obligation to, as the case may be,
solicit purchases on an agency basis for, or purchase, the Shares pursuant to a
Purchase Notice shall be subject to the satisfaction of the following conditions
at the time of delivery of the Purchase Notice, the time of the commencement of
trading on the Exchange on the Purchase Date and at the time of closing on the
Closing Date:

     (a)  the representations and warranties on the part of the Company herein
          contained or contained in any certificate of an officer or officers of
          the Company delivered pursuant to the provisions hereof shall be true
          and correct in all material respects;

     (b)  the Company shall have performed and observed its covenants and other
          obligations hereunder in all material respects;

     (c)  from the date of delivery of the Purchase Notice until the Closing
          Date, trading in the Common Stock on the Exchange shall not have been
          suspended;

     (d)  the Shares to be issued pursuant to the Purchase Notice shall have
          been approved for listing on the Exchange, subject only to notice of
          issuance;

     (e)  the Company shall furnish evidence reasonably satisfactory to the
          Agent and its counsel that the Registration Statement has become
          effective; and

     (f)  no amendment or supplement to the Registration Statement or Prospectus
          shall have been filed to which the Agent shall have objected in
          writing.

     9. Termination by Agent. The obligations of the Agent hereunder shall be
subject to termination at any time in the sole and absolute discretion of the
Agent, (i) if any of the conditions specified in Section 6 shall not have been
fulfilled when and as required by this Agreement to be fulfilled, or (ii) if
there has been since the respective dates as of which information is given in
the Registration Statement, any material adverse change, or any development
involving a prospective material adverse change, in or affecting the assets,
operations, business or condition (financial or otherwise) of the Company,
whether or not arising in the ordinary course of business, or (iii) if there has
since the date hereof occurred an outbreak or escalation of hostilities or other
national or international calamity or crisis or change in economic, political or
other conditions the effect of which on the financial markets of the United
States is such as to make it, in the judgment of the Agent, impracticable to
market or deliver the Shares or enforce contracts for the sale of the Shares, or
(iv) if trading in any securities of the Company has been suspended by the
Commission or by the NASD or if trading generally on the Nasdaq National Market
System has been suspended (including automatic halt in trading pursuant to
market-decline triggers other than those in which solely program trading is
temporarily halted), or limitations on prices for trading (other than
limitations on hours or numbers of days of trading) have been fixed, or maximum
ranges for prices for securities have

                                     - 20 -
<PAGE>

been required, by such exchange or the NASD or by order of the Commission or any
other governmental authority, or (v) if there has been any downgrading in the
rating of any of the Company's debt securities or preferred stock by any
"nationally recognized statistical rating organization" (as defined for purposes
of Rule 436(g) under the Securities Act), or (vi) if any federal or state
statute, regulation, rule or order of any court or other governmental authority
has been enacted, published, decreed or otherwise promulgated which in the
reasonable opinion of the Agent has a Material Adverse Effect or will have a
Material Adverse Effect on the assets, operations, business or condition
(financial or otherwise) of the Company, or (vii) if any action has been taken
by any federal, state or local government or agency in respect of its monetary
or fiscal affairs which in the reasonable opinion of the Agent has a Material
Adverse Effect on the securities markets in the United States, or (viii) if any
other material adverse change to the assets, operations, business or condition
(financial or otherwise) of the Company has occurred, and in the case of any of
the events specified in clauses (i) through (viii), such event, singly or
together with any other such events, makes it, in the judgment of the Agent,
impracticable or inadvisable to market or deliver the Shares on the terms and in
the manner contemplated in the Prospectus.

     If the Agent elects to terminate this Agreement as provided in this Section
9, the Company shall be notified promptly by telephone, promptly confirmed by
facsimile. If a Purchase Notice is pending at the time of termination, the Agent
may declare such Purchase Notice void or may require the Company to complete the
sale of Shares as specified in the Purchase Notice, at the Agent's sole
discretion.

     If the solicitation of purchases on an agency basis or purchase by the
Agent as principal of the Shares, as contemplated by this Agreement, is not
carried out by the Agent for any reason permitted under this Agreement or if
such sale is not carried out because the Company shall be unable to comply in
all material respects with any of the terms of this Agreement, the Company shall
not be under any obligation or liability under this Agreement (except to the
extent provided in Sections 5(m) and 11 hereof) and the Agent shall be under no
obligation or liability to the Company under this Agreement (except to the
extent provided in Section 11 hereof) or to one another hereunder.

     10. Termination by Company. Subject to Sections 8 and 9, if the Agent
defaults in its obligation to consummate a purchase of Shares to be purchased by
it hereunder (otherwise than for a reason sufficient to justify the termination
of this Agreement under the provisions of Section 9 hereof) and does not cure
such default within five Exchange Business Days, the Company may terminate this
Agreement by notice to the Agent.

     11. Indemnity and Contribution.

     (a)  The Company agrees to indemnify, defend and hold harmless the Agent,
          its directors and officers and any person who controls the Agent
          within the meaning of Section 15 of the Act or Section 20 of the 1934
          Act, and the successors and assigns of all of the foregoing persons
          from and against any loss, damage, expense, liability or claim
          (including the reasonable cost of investigation) which, jointly or
          severally, the Agent or any such person may incur under the Act, the
          1934 Act, the common law or otherwise, insofar as such loss, damage,
          expense, liability or claim arises out of or is based upon any untrue
          statement or alleged untrue statement of a

                                     - 21 -
<PAGE>

          material fact contained in the Registration Statement (or in the
          Registration Statement as amended by any post-effective amendment
          thereof by the Company) or in a Prospectus (the term "Prospectus" for
          the purpose of this Section 11 being deemed to include any preliminary
          prospectus, the Prospectus and the Prospectus as it may be amended or
          supplemented by the Company), or arises out of or is based upon any
          omission or alleged omission to state a material fact required to be
          stated in either such Registration Statement or Prospectus or
          necessary to make the statements made therein not misleading, except
          insofar as any such loss, damage, expense, liability or claim arises
          out of or is based upon any untrue statement or alleged untrue
          statement of a material fact contained in and in conformity with
          information furnished in writing by the Agent to the Company expressly
          for use with reference to the Agent in such Registration Statement or
          such Prospectus or arises out of or is based upon any omission or
          alleged omission to state a material fact by the Agent in connection
          with such information required to be stated in such Registration
          Statement or such Prospectus or necessary to make such information not
          misleading.

     If any action, suit or proceeding (together, a "Proceeding") is brought
     against the Agent or any such person in respect of which indemnity may be
     sought against the Company pursuant to the foregoing paragraph, the Agent
     or such person shall promptly notify the Company in writing of the
     institution of such Proceeding and the Company shall assume the defense of
     such Proceeding, including the employment of counsel reasonably
     satisfactory to such indemnified party and payment of all reasonable fees
     and expenses; provided, however, that the omission to so notify the Company
     shall not relieve the Company from any liability which the Company may have
     to the Agent or any such person or otherwise. The Agent or such person
     shall have the right to employ its or their own counsel in any such case,
     but the fees and expenses of such counsel shall be at the expense of such
     Agent or of such person unless the employment of such counsel shall have
     been authorized in writing by the Company in connection with the defense of
     such Proceeding or the Company shall not have, within a reasonable period
     of time in light of the circumstances, employed counsel to have charge of
     the defense of such Proceeding or such indemnified party or parties shall
     have reasonably concluded based on advice of counsel that there may be
     defenses available to it or them which are different from, additional to or
     in conflict with those available to the Company, in which case the Company
     shall not have the right to direct the defense of such Proceeding on behalf
     of the indemnified party or parties, in any of which events such reasonable
     fees and expenses shall be borne by the Company and paid as incurred, it
     being understood, however, that the Company shall not be liable for the
     reasonable expenses of more than one separate counsel, in addition to any
     local counsel, in any one Proceeding or series of related Proceedings in
     the same jurisdiction representing the indemnified parties who are parties
     to such Proceeding. The Company shall not be liable for any settlement of
     any Proceeding effected without its written consent but if settled with the
     written consent of the Company, the Company agrees to indemnify and hold
     harmless the Agent and any such person from and against any loss or
     liability by reason of such settlement. Notwithstanding the foregoing
     sentence, if at any time an indemnified

                                     - 22 -
<PAGE>
     party shall have requested an indemnifying party to reimburse the
     indemnified party for fees and expenses of counsel as contemplated by the
     second sentence of this paragraph, then the indemnifying party agrees that
     it shall be liable for any settlement of any Proceeding effected without
     its written consent if (i) such settlement is entered into more than 60
     Exchange Business Days after receipt by such indemnifying party of the
     aforesaid request, (ii) such indemnifying party shall not have reimbursed
     the indemnified party in accordance with such request before the date of
     such settlement and (iii) such indemnified party shall have given the
     indemnifying party at least 30 days' prior notice of its intention to
     settle. No indemnifying party shall, without the prior written consent of
     the indemnified party, effect any settlement of any pending or threatened
     Proceeding in respect of which any indemnified party is or could have been
     a party and indemnity could have been sought hereunder by such indemnified
     party, unless such settlement includes an unconditional release of such
     indemnified party from all liability on claims that are the subject matter
     of such Proceeding and does not include an admission of fault, culpability
     or a failure to act, by or on behalf of such indemnified party.

     (b)  The Agent agrees to indemnify, defend and hold harmless the Company,
          its directors and officers, and any person who controls the Company
          within the meaning of Section 15 of the Act or Section 20 of the 1934
          Act, and the successors and assigns of all of the foregoing persons
          from and against any loss, damage, expense, liability or claim
          (including the reasonable cost of investigation) which, jointly or
          severally, the Company or any such person may incur under the Act, the
          1934 Act, the common law or otherwise, insofar as such loss, damage,
          expense, liability or claim arises out of or is based upon any untrue
          statement or alleged untrue statement of a material fact contained in
          and in conformity with information furnished in writing by the Agent
          to the Company expressly for use with reference to the Agent in the
          Registration Statement, as amended by any post-effective amendment
          thereof by the Company, or in a Prospectus, or arises out of or is
          based upon any omission or alleged omission to state a material fact
          in connection with such information required to be stated in such
          Registration Statement or such Prospectus or necessary to make such
          information not misleading.

     If any Proceeding is brought against the Company or any such person in
     respect of which indemnity may be sought against the Agent pursuant to the
     foregoing paragraph, the Company or such person shall promptly notify the
     Agent in writing of the institution of such Proceeding and the Agent shall
     assume the defense of such Proceeding, including the employment of counsel
     reasonably satisfactory to such indemnified party and payment of all fees
     and expenses; provided, however, that the omission to so notify the Agent
     shall not relieve the Agent from any liability which the Agent may have to
     the Company or any such person or otherwise. The Company or such person
     shall have the right to employ its own counsel in any such case, but the
     fees and expenses of such counsel shall be at the expense of the Company or
     such person unless the employment of such counsel shall have been
     authorized in writing by the Agent in connection with the defense of such
     Proceeding or the Agent shall not have, within a reasonable period of time
     in light of the circumstances, employed

                                     - 23 -
<PAGE>
     counsel to have charge of the defense of such Proceeding or such
     indemnified party or parties shall have reasonably concluded that there may
     be defenses available to it or them which are different from or additional
     to or in conflict with those available to such Agent (in which case the
     Agent shall not have the right to direct the defense of such Proceeding on
     behalf of the indemnified party or parties, but the Agent may employ
     counsel and participate in the defense thereof but the fees and expenses of
     such counsel shall be at the expense of the Agent), in any of which events
     such reasonable fees and expenses shall be borne by the Agent and paid as
     incurred (it being understood, however, that the Agent shall not be liable
     for the reasonable expenses of more than one separate counsel (in addition
     to any local counsel) in any one Proceeding or series of related
     Proceedings in the same jurisdiction representing the indemnified parties
     who are parties to such Proceeding). The Agent shall not be liable for any
     settlement of any such Proceeding effected without the written consent of
     the Agent but if settled with the written consent of the Agent, the Agent
     agrees to indemnify and hold harmless the Company and any such person from
     and against any loss or liability by reason of such settlement.
     Notwithstanding the foregoing sentence, if at any time an indemnified party
     shall have requested an indemnifying party to reimburse the indemnified
     party for fees and expenses of counsel as contemplated by the second
     sentence of this paragraph, then the indemnifying party agrees that it
     shall be liable for any settlement of any Proceeding effected without its
     written consent if (i) such settlement is entered into more than 60
     Exchange Business Days after receipt by such indemnifying party of the
     aforesaid request, (ii) such indemnifying party shall not have reimbursed
     the indemnified party in accordance with such request before the date of
     such settlement and (iii) such indemnified party shall have given the
     indemnifying party at least 30 days' prior notice of its intention to
     settle. No indemnifying party shall, without the prior written consent of
     the indemnified party, effect any settlement of any pending or threatened
     Proceeding in respect of which any indemnified party is or could have been
     a party and indemnity could have been sought hereunder by such indemnified
     party, unless such settlement includes an unconditional release of such
     indemnified party from all liability on claims that are the subject matter
     of such Proceeding.

     (c)  If the indemnification provided for in this Section 11 is unavailable
          to an indemnified party under subsections (a) and (b) of this Section
          11 in respect of any losses, damages, expenses, liabilities or claims
          referred to therein, then each applicable indemnifying party, in lieu
          of indemnifying such indemnified party, shall contribute to the amount
          paid or payable by such indemnified party as a result of such losses,
          damages, expenses, liabilities or claims (i) in such proportion as is
          appropriate to reflect the relative benefits received by the Company
          on the one hand and the Agent on the other hand from the offering of
          the Shares or (ii) if the allocation provided by clause (i) above is
          not permitted by applicable law, in such proportion as is appropriate
          to reflect not only the relative benefits referred to in clause (i)
          above but also the relative fault of the Company on the one hand and
          of the Agent on the other in connection with the statements or
          omissions which resulted in such losses, damages, expenses,
          liabilities or claims, as well as any other relevant equitable
          considerations. The relative benefits received by the

                                     - 24 -
<PAGE>
          Company on the one hand and the Agent on the other shall be deemed to
          be in the same respective proportions as the total proceeds from the
          offering (net of underwriting discounts and commissions but before
          deducting expenses) received by the Company and the total underwriting
          discounts and commissions received by the Agent, bear to the aggregate
          public offering price of the Shares. The relative fault of the Company
          on the one hand and of the Agent on the other shall be determined by
          reference to, among other things, whether the untrue statement or
          alleged untrue statement of a material fact or omission or alleged
          omission relates to information supplied by the Company or by the
          Agent and the parties' relative intent, knowledge, access to
          information and opportunity to correct or prevent such statement or
          omission. The amount paid or payable by a party as a result of the
          losses, damages, expenses, liabilities and claims referred to in this
          subsection shall be deemed to include any legal or other fees or
          expenses reasonably incurred by such party in connection with
          investigating, preparing to defend or defending any Proceeding.

     (d)  The Company and the Agent agree that it would not be just and
          equitable if contribution pursuant to this Section 11 were determined
          by pro rata allocation or by any other method of allocation that does
          not take account of the equitable considerations referred to in
          subsection (c) above. Notwithstanding the provisions of this Section
          11, the Agent shall not be required to contribute any amount in excess
          of the amount by which the total price at which the Shares
          underwritten by such Agent and distributed to the public were offered
          to the public exceeds the amount of any damage which the Agent has
          otherwise been required to pay by reason of such untrue statement or
          alleged untrue statement or omission or alleged omission. No person
          guilty of fraudulent misrepresentation (within the meaning of Section
          11(f) of the Act) shall be entitled to contribution from any person
          who was not guilty of such fraudulent misrepresentation.

     The indemnity and contribution agreements contained in this Section 11 and
     the covenants, warranties and representations of the Company contained in
     this Agreement shall remain in full force and effect regardless of any
     investigation made by or on behalf of the Agent, its directors or officers
     or any person (including each officer or director of such person) who
     controls the Agent within the meaning of Section 15 of the Act or Section
     20 of the 1934 Act, or by or on behalf of the Company, its directors or
     officers or any person who controls the Company within the meaning of
     Section 15 of the Act or Section 20 of the 1934 Act, and shall survive any
     termination of this Agreement or the issuance and delivery of the Shares.
     The Company and the Agent agree promptly to notify each other of the
     commencement of any Proceeding against it and, against any of their
     respective officers or directors in connection with the issuance and sale
     of the Shares, or in connection with the Registration Statement or
     Prospectus.

     12. Notices. All notices hereunder shall be in writing and delivered by
hand, overnight courier, mail or facsimile, and if to the Agent, shall be
sufficient in all respects if delivered to UBS Warburg LLC, 677 Washington
Blvd., Stamford, CT 06901, with separate copies to the

                                     - 25 -
<PAGE>

attention of: David Lessen, William Carrington and Young Kim, Facsimile No.
(203) 719-7031; Operations - Corporate Action Department, Facsimile No. (203)
719-0795; and Legal Affairs (Equities Group), Facsimile No. (203) 719-0680, and
if to the Company, shall be sufficient in all respects if delivered or sent to
the Company at the offices of the Company at 80 SW 8th Street, Miami, Florida
33130, Attention: Phil Gevas. Notwithstanding the foregoing, Purchase Notices
shall be delivered to the Agent by facsimile at (203) 719-7031 and receipt
confirmed by telephone at (203) 719-8931 or (203) 719-8451, and notices to the
Company pursuant to Section 1(d) shall be delivered to the Company by facsimile
at (305) 374-7615 and receipt confirmed by telephone at (305) 374-7338. A
Purchase Notice received by the Agent after 4 p.m. on an Exchange Business Day
or on a day that is not an Exchange Business Day shall be deemed to have been
delivered on the next following Exchange Business Day.

     13. Governing Law; Construction. This Agreement and any claim, counterclaim
or dispute of any kind or nature whatsoever arising out of or in any way
relating to this Agreement ("Claim"), directly or indirectly, shall be governed
by, and construed in accordance with, the laws of the State of New York, other
than rules governing choice of applicable law. The Section headings in this
Agreement have been inserted as a matter of convenience of reference and are not
a part of this Agreement.

     14. Submission to Jurisdiction. Except as set forth below, no Claim may be
commenced, prosecuted or continued in any court other than the courts of the
State of New York located in the City and County of New York or in the United
States District Court for the Southern District of New York, which courts shall
have nonexclusive jurisdiction over the adjudication of such matters, and the
Company consents to the jurisdiction of such courts and personal service with
respect thereto. The Company hereby consents to personal jurisdiction, service
and venue in any court in which any Claim arising out of or in any way relating
to this Agreement is brought by any third party against UBS Warburg LLC or any
indemnified party. Each of UBS Warburg LLC and the Company, on its behalf and,
to the extent permitted by applicable law, on behalf of its stockholders and
affiliates, waives all right to trial by jury in any action, proceeding or
counterclaim, whether based upon contract, tort or otherwise, in any way arising
out of or relating to this Agreement. The Company agrees that a final judgment
in any such action, proceeding or counterclaim brought in any such court shall
be conclusive and binding upon the Company and may be enforced in any other
courts in the jurisdiction of which the Company is or may be subject, by suit
upon such judgment.

     15. Parties in Interest. The Agreement herein set forth has been and is
made solely for the benefit of the Agent and the Company and to the extent
provided in Section 11 hereof the controlling persons, directors and officers
referred to in such section, and their respective successors, assigns, heirs,
personal representatives and executors and administrators. No other person,
partnership, association or corporation (including a purchaser, as such
purchaser, from the Agent) shall acquire or have any right under or by virtue of
this Agreement.

     16. Counterparts. This Agreement may be signed by the parties in one or
more counterparts, which together shall constitute one and the same agreement
among the parties.

                                     - 26 -
<PAGE>

     17. Successors and Assigns. This Agreement shall be binding upon the Agent
and the Company and their successors and assigns and any successor or assign of
any substantial portion of the Company's and the Agent's respective businesses
and/or assets.

     18. Miscellaneous. UBS Warburg LLC, an indirect, wholly owned subsidiary of
UBS AG, is not a bank and is separate from any affiliated bank, including any
U.S. branch or agency of UBS AG. Because UBS Warburg LLC is a separately
incorporated entity, it is solely responsible for its own contractual
obligations and commitments, including obligations with respect to sales and
purchases of securities. Securities sold, offered or recommended by UBS Warburg
LLC are not deposits, are not insured by the Federal Deposit Insurance
Corporation, are not guaranteed by a branch or agency of UBS AG, and are not
otherwise an obligation or responsibility of a branch or agency of UBS AG.

     A lending affiliate of UBS Warburg LLC may have lending relationships with
issuers of securities underwritten or privately placed by UBS Warburg LLC. To
the extent required under the securities laws, prospectuses and other disclosure
documents for securities underwritten or privately placed by UBS Warburg LLC
will disclose the existence of any such lending relationships and whether the
proceeds of the issue will be used to repay debts owed to affiliates of UBS
Warburg LLC.

     UBS Warburg LLC and one or more of its affiliates may make markets in the
Common Stock or other securities of the Company, in connection with which they
may buy and sell, as agent or principal, for long or short account, shares of
Common Stock or other securities of the Company, at the same time that UBS
Warburg LLC is acting as Agent pursuant to this Agreement.

                                     - 27 -

<PAGE>

     If the foregoing correctly sets forth the understanding among the Company
and the Agent, please so indicate in the space provided below for the purpose,
whereupon this letter and your acceptance shall constitute a binding agreement
between the Company and the Agent.

                                        Very truly yours,


                                        APHTON CORPORATION


                                        By:_______________________
                                        Name:
                                        Title:


Accepted and agreed to as of the date first above written:

UBS WARBURG LLC


By:__________________________
     Name:
     Title:


By:__________________________
     Name:
     Title:

                                     - 28 -

<PAGE>
                                                                      Schedule I

                           Subsidiaries of the Company

                  Currently, the Company has no subsidiaries.



                                     - 29 -


<PAGE>

                                                                       Exhibit A

                              Officers' Certificate

1.   The representations and warranties of the Company in the Distribution
     Agreement are true and correct in all material respects as of the date
     hereof as though made on and as of this date;

2.   The Company has performed all obligations and satisfied all conditions
     on its part to be performed or satisfied pursuant to the Distribution
     Agreement at or prior to the date hereof;

3.   The Company's Registration Statement (File No. 333-72964) under the
     Securities Act of 1933 has become effective; no stop order suspending the
     effectiveness of such Registration Statement has been issued and no
     proceeding for that purpose has been initiated or threatened by the
     Securities and Exchange Commission (the "Commission"); and all requests for
     additional information on the part of the Commission have been complied
     with; and

4.   Except as otherwise disclosed in writing to the Agent by the Company,
     subsequent to the respective dates as of which information is given in the
     Registration Statement and the Prospectus, there has not been (i) any
     material adverse change, or any development involving a prospective
     material adverse change, in the business, prospects, properties or assets
     described or referred to in the Registration Statement, or the results of
     operations, condition (financial or otherwise), business or operations of
     the Company and the Subsidiaries, whether or not arising in the ordinary
     course of business, or (ii) any transaction which is material to the
     Company or the Subsidiaries, planned or entered into by the Company or any
     of the Subsidiaries, or (iii) any obligation, direct or contingent, which
     is material to the Company and the Subsidiaries, incurred by the Company or
     the Subsidiaries, except obligations incurred in the ordinary course of
     business, or (iv) any material change in the capital stock or outstanding
     indebtedness of the Company or the Subsidiaries, or (v) any dividend or
     distribution of any kind declared, paid or made on the capital stock of the
     Company; and neither the Company nor the Subsidiaries has any material
     contingent obligation which is not disclosed in the Registration Statement.

                                     - 30 -
<PAGE>


                                                                       Exhibit B

                           Opinion of White & Case LLP

                     [Aphton Corporation - Form of Opinion]


i.   The Company has been duly incorporated and is validly existing as a
     corporation in corporate good standing under the laws of the State of
     Delaware and has the corporate power and authority to own, lease and
     operate its properties and conduct its business as described in the
     Registration Statement, and to enter into this Agreement, to issue, sell
     and deliver the Shares and consummate the transactions contemplated in the
     Prospectus;

ii.  The common stock of the Company, including the Shares, conforms in all
     material respects to the description thereof contained in the Registration
     Statement and Prospectus;

iii. The Shares have been duly and validly authorized by the Company for offer,
     sale, issuance and delivery pursuant to this Agreement and, when issued and
     delivered against payment therefor as provided in the Distribution
     Agreement, will be duly and validly issued and fully paid and
     non-assessable;

iv.  To such counsel's knowledge, the Company is duly qualified to do business
     as a foreign corporation and in good standing in each jurisdiction where
     the ownership or leasing of its properties or the conduct of its business
     requires such qualification, except where the failure to so qualify would
     not have a material adverse effect on the business, properties, financial
     condition or results of operation of the Company taken as a whole (a
     "Material Adverse Effect");

v.   To such counsel's knowledge and other than as set forth in the Prospectus,
     there are no actions, suits, claims, investigations or proceedings pending
     or threatened to which the Company is a party or of which any of their
     respective properties is subject at law or in equity, or before or by any
     federal, state or local governmental or regulatory commission, board, body,
     authority or agency, which could prevent consummation of the transactions
     contemplated hereby or which are required to be described in the
     Registration Statement or the Prospectus but are not so described;

vi.  This Agreement has been duly authorized, executed and delivered by the
     Company;

vii. The execution, delivery and performance of this Agreement, the issuance and
     sale of the Shares and the consummation of the transactions contemplated
     hereby will not conflict with, or result in any breach of or constitute a
     default under (nor constitute any event which with notice, lapse of time,
     or both would result in any breach of, or constitute a default under), any
     provisions of the charter or by-laws of the Company or, to such counsel's
     knowledge, under any provision of any license, indenture, mortgage, deed of
     trust, bank loan or credit agreement or other evidence of indebtedness, or
     any lease, contract or other agreement or instrument to which the Company
     is a party or by which

                                     - 31 -

<PAGE>

     any of them or their respective properties may be bound or affected and
     which have been filed by the Company with the Commission under the
     Securities Exchange Act of 1934, as amended (the "Exchange Act"), and are
     listed in the exhibit index to the Company's most recent Annual Report on
     Form 10-K or are subsequently filed under the Exchange Act, or under any
     decree, judgment or order known to such counsel to be applicable to the
     Company or under any federal, state or local law, regulation or rule;

viii. No approval, authorization, consent or order of or filing with any
     national, state or local governmental or regulatory commission, board,
     body, authority or agency is required in connection with the issuance and
     sale of the Shares or the consummation by the Company of the transactions
     as contemplated hereby except such as may be required by the Act and the
     applicable rules and regulations thereunder, the securities or blue sky
     laws of the various jurisdictions in which the Shares are being offered by
     the Agent (as to which such counsel expresses no opinion) or under the
     rules and regulations of the National Association of Securities Dealers,
     Inc. ("NASD") (as to which such counsel expresses no opinion);

ix.  The statements set forth in the Prospectus in the second sentence of the
     fourth paragraph under the caption "The Company", under the caption "Risk
     Factors--Our potential products are in the early stages of product
     development", "Risk Factors--We expect to continue incurring operating
     losses in the next several years", "Risk Factors--We have substantial
     capital requirements and we may not be able to obtain additional
     financing", "Risk Factors--Our different approach to disease treatment may
     not prove successful", "Risk Factors--The development of our products is
     subject to extensive regulation", "Risk Factors--We depend on strategic
     alliances and may need additional strategic collaborators in the future",
     "Risk Factors--The industry in which we operate is characterized by rapid
     technological change and intense competition", "Risk Factors--Our ability
     to enforce our patents and proprietary rights is uncertain", "Risk
     Factors--We depend on key personnel", "Risk Factors--We may be exposed to
     product liability claims and uninsured risk", "Risk Factors--Our business
     involves the use of hazardous materials that could expose us to
     environmental liability", "Risk Factors--We depend on others for
     manufacturing and marketing", "Risk Factors--Future healthcare reforms may
     adversely affect our financial results", "Risk Factors--Our success depends
     on third party reimbursement", "Risk Factors--Ownership of our common stock
     is concentrated", "Risk Factors--The price of our common stock may be
     volatile", "Risk Factors--The exercise of outstanding warrants and other
     rights to obtain additional shares could dilute the value of the shares"
     and Item 15 of the Registration statement, insofar as they purport to
     describe the provisions of the laws and documents referred to therein,
     fairly summarize the matters referred to therein in all material respects;

x.   The Company is not and, after giving effect to the offering and sale of the
     Shares, will not be required to register as an "investment company" as such
     term is defined in the Investment Company Act of 1940, as amended (the
     "Investment Company Act");

xi.  The documents incorporated by reference in the Prospectus or any further
     amendment or supplement thereto made by the Company prior to the date of
     delivery of such opinion (other than the financial statements and related
     schedules therein, as to which such

                                     - 32 -

<PAGE>

     counsel need express no opinion), when they became effective or were filed
     with the Commission, as the case may be, complied as to form in all
     material respects with the requirements of the Act or the Exchange Act, as
     applicable, and the rules and regulations of the Commission thereunder;

xii. The Registration Statement and the Prospectus and any further amendments
     and supplements thereto made by the Company prior to the date of delivery
     of such opinion (other than the financial statements and related schedules
     therein, as to which such counsel need express no opinion) comply as to
     form in all material respects with the requirements of the Act and the
     rules and regulations of the Commission thereunder;

     Such counsel shall also state that, although they do not assume any
     responsibility for the accuracy, completeness or fairness of the statements
     contained in the Registration Statement or the Prospectus, except for those
     referred to in the opinion in paragraphs (ii) and (ix) above, nothing has
     come to their attention that has led them to believe (a) that, as of its
     effective date, the Registration Statement or, as of its date, any further
     amendment thereto made by the Company prior to the date of delivery of such
     opinion (other than the financial statements and related schedules therein,
     as to which such counsel need express no belief) contained an untrue
     statement of a material fact or omitted to state a material fact required
     to be stated therein or necessary to make the statements therein not
     misleading or (b) that, as of its date, the Prospectus and documents
     incorporated by reference therein or any further amendment or supplement to
     the Prospectus (and documents incorporated by reference therein) made by
     the Company prior to the time and date of delivery of such opinion (other
     than the financial statements and related schedules therein, as to which
     such counsel need express no belief) contained an untrue statement of a
     material fact or omitted to state a material fact necessary to make the
     statements therein, in the light of the circumstances under which they were
     made, not misleading or (c) that, as of the date of delivery of such
     opinion, either the Registration Statement or the Prospectus or any further
     amendment or supplement thereto made by the Company prior to the time and
     date of delivery of such opinion (other than the financial statements and
     related schedules therein, as to which such counsel need express no belief)
     contains an untrue statement of a material fact or omits to state a
     material fact necessary to make the statements therein, in the light of the
     circumstances under which they were made, not misleading; and they do not
     know of any amendment to the Registration Statement required to be filed or
     of any contracts or other documents of a character required to be filed as
     an exhibit to the Registration Statement or required to be incorporated by
     reference into the Prospectus or required to be described in the
     Registration Statement or the Prospectus which are not filed or
     incorporated by reference or described as required.

                                     - 33 -

<PAGE>

                                                                       Exhibit C

                Intellectual Property Opinion of White & Case LLP

                     [Form of Intellectual Property Opinion]


[ADDRESS]

[OPINION LETTER TO AGENT]


RE:    Aphton Corporation
       Pursuant to Distribution Agreement


Ladies and Gentlemen:

We are Intellectual Property Counsel for the Company in connection with certain
intellectual property matters and in connection with the distribution of shares
of Aphton Corporation (the "Company") common stock ("Common Stock") pursuant to
the Distribution Agreement as agreed to on December __, 2001. This opinion is
provided pursuant to the above referenced Distribution Agreement between the
Company and the Underwriters.

In connection with this opinion, we have been asked to review statements
relating to patents, patent applications and trade secrets (the "Intellectual
Property") of the Company and as made in or referenced by the Distribution
Agreement. We have made this review and provide our opinion with respect to the
above-identified sections of these documents. Our opinion is limited to
Intellectual Property matters, as noted above.

We are familiar with certain of the technology used by the Company in its
business, to the extent of its disclosure to us by the Company, which is the
subject matter of certain of the patents, patent applications and trade secrets
described in the above identified documents. The opinions and beliefs expressed
in this letter represent our considered judgment and are based upon compilations
of applicable laws generally available to the public and effective as of the
date hereof.

As used in this letter, the phrase "to our knowledge" when used as a
qualification with respect to the existence or absence of any matter, means
that, during our representation of the Company and having no independent
investigation with respect thereto, no information has come to our attention
which has given us actual knowledge of the existence of facts contrary to the
stated existence or absence of the matter.

Based on our review of the above-identified sections of the Distribution
Agreement, and subject to and limited by the foregoing and the exceptions and
limitations set forth below, we offer the following opinions and conclusions:

                                     - 34 -

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1. For the purpose of this opinion, the terms "know," "known," or "knowledge"
refer to the actual knowledge by us, as well as the knowledge arising from our
review of documents and materials relevant to the matters addressed in the
paragraphs below, and the knowledge arising from our inquiry of employees or
officers of the Company familiar with a matter to which this opinion pertains.

2. All patents and pending patent applications ("Patents") that are owned by or
licensed to the Company are listed on IP Schedule A, attached hereto.
Information concerning the application number, filing data, and status of the
applications encompassed by our representation of the Company is set forth in IP
Schedule A.

3. Except as set forth below, to our knowledge, the statements in the
Distribution Agreement, insofar as such statements pertain to Intellectual
Property matters, accurately and fairly represent the information referred to
therein. We express no opinion, however, as to the bases upon which the Company
decides to file patent applications, the dependency of the Company's commercial
success on any factors including protection of proprietary technology and the
procurement and enforceability of patents, nor as to the Company's reliance on
various methods to protect its proprietary rights.

4. To our knowledge, and based upon a representation by the Company regarding
the conception and reduction to practice of the patents, patent applications and
trade secrets related to the technology described in the above-identified
documents, (A) there are no rights of parties other than the Company to any of
the patents, patent applications or trade secret rights related to the
technology described in the Distribution Agreement, (B) there are no pending or
threatened actions, suits, proceedings or claims by others challenging the
Company's rights to or in any such patents, patent applications or trade secret
rights and (C) there are no pending or threatened actions, suits, proceedings or
claims by others that the Company is infringing or otherwise violating any
patent or trade secret rights of others.

5. To the best of our knowledge, the Company and its licensors have complied
with the examination requirements of the United States Patent and Trademark
Office ("USPTO") duty of candor and disclosure for each of the United States
Patent listed in IP Schedule A. No fact has come to such counsel's attention
that causes such counsel to question the enforceability of any of the Patents,
or to question the validity of any claim of an issued patent or pending patent
application listed on IP Schedule A.

6. We are aware of no legal or governmental proceedings relating to the
Company's patent rights, other than normal ex parte USPTO examination
proceedings. No patent application listed in IP Schedule A has been formally
abandoned, and all patents have been lawfully issued.

7. To our knowledge, there are no facts or circumstances which, if asserted in
litigation, would be likely to render any of the trade secret rights reflected
in the Company's filed patent applications invalid, or unenforceable except to
the extent they have been or will be disclosed upon publication of such patent
applications or upon the issuance of patents.

8. There are no agreements with third parties relating to the acquisition,
licensing and/or transfer of intellectual property rights which have or are
anticipated to have a material impact on

                                     - 35 -

<PAGE>

the Company's existing or future business, including license agreements, joint
venture agreements, marketing and/or distribution agreements or other
collaboration agreements, that are not currently in effect or that will be
expiring soon, nor further has there been any notice of termination or other act
indicating a desire to terminate any of the aforesaid agreements.

9. Except as described in the above identified documents, we are not aware of
any facts that prevent the Company from using its intellectual property and
know-how to conduct its business or from enforcing its rights to its patents or
patent applications.

10. We are not aware of any facts or prior art that would lead us to believe
that any of the Companies patents are or may infringe the patent or patents of
third parties.

11. We believe and have so informed the Company that its _________ products are
covered by one or more of the issued patents and the claims therein listed in IP
Schedule A, attached hereto.

This letter is limited to the matters set forth herein, and no matter may be
inferred or implied beyond the matters expressly stated in this letter. We
assume no obligation to advise you, subsequent to the delivery of this letter,
of any matters that could result in a change in the opinions or beliefs set
forth herein. This letter has been prepared solely for your use in connection
with the Purchase and/or Distribution of stock shares under the appropriate
documents, and may not be used for any other purpose, or be relied upon by any
other person or entity. It should not be quoted in whole or in part or otherwise
be referred to, nor be filed with nor furnished to any governmental agency or
other person or entity, without the prior written consent of the undersigned.



                                            Very Truly Yours,



                                            [Law Firm]

                                     - 36 -

<PAGE>



<TABLE>
<CAPTION>
                                                         IP SCHEDULE A--APHTON CORPORATION


=============================================================================================================================
Patent No.   Country    Filing   Issue   Inventors   Explanation of    Maintenance   APH     Status  Oppositions   Litigation
Serial No.               Date     Date                Relation to      Fee/Annuity   Interest        Interferences  Status
  (Title)                                           Company Business    Fee Status                      Status
-----------------------------------------------------------------------------------------------------------------------------
<S>          <C>       <C>      <C>      <C>        <C>                <C>           <C>     <C>      <C>          <C>
-----------------------------------------------------------------------------------------------------------------------------
                       00/00/00 00/00/00
-----------------------------------------------------------------------------------------------------------------------------

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

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

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

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

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

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

=============================================================================================================================
</TABLE>

                                     - 37 -
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                                                                       Exhibit D

                    Opinion of Stroock & Stroock & Lavan LLP

                                [Form of Opinion]

1.   The Company is a corporation duly organized, validly existing and in good
     standing under the laws of the State of Delaware. The Company is qualified
     to do business as a foreign corporation in good standing in the State of
     Florida. [Each Subsidiary of the Company has been duly organized or formed
     and is validly existing as a corporation, limited partnership, limited
     liability company or partnership, as the case may be, in good standing
     under the laws of its jurisdiction of organization or formation. Each
     Subsidiary of the Company is qualified to do business as a foreign
     corporation, limited partnership, limited liability company or partnership,
     as the case may be, in good standing in Delaware.]

2.  All of the outstanding shares of capital stock of the Company have been
     duly authorized and validly issued and are fully paid and nonassessable and
     were not issued in violation of or subject to any preemptive or similar
     rights. [All of the issued and outstanding shares of capital stock of each
     Subsidiary of the Company have been duly authorized and validly issued, and
     are fully paid and nonassessable and were not issued in violation of or
     subject to any preemptive or similar rights. The issued shares of capital
     stock of each of the Company's Subsidiaries are owned of record, directly
     or indirectly, by the Company free and clear of any and all liens, charges,
     claims, security interests or encumbrances.]

3.  The Company has full corporate power and authority to enter into the
     Distribution Agreement and to issue, sell and deliver the Shares to the
     Agent as agent or to the Agent as principal, as provided in the
     Distribution Agreement, and the Distribution Agreement has been duly
     authorized, executed and delivered by the Company and is the legal, valid
     and binding obligation of the Company, enforceable against the Company in
     accordance with its terms.

While we have not verified, and are not passing upon and do not assume any
responsibility for, the accuracy, completeness or fairness of the statements
contained in the Registration Statement and the Prospectus, we have participated
in conferences with certain officers and other representatives of the Company,
counsel for the Company, representatives of the independent auditors for the
Company and your representatives, at which the contents of the Registration
Statement and Prospectus and related matters were discussed and, on the basis of
the foregoing (relying as to materiality to a large extent on the opinions of
officers and other representatives of the Company), no facts have come to our
attention that lead us to believe that the Registration Statement (except with
respect to the financial statements, schedules and other financial data,
including therein, as to which we make no statement), at the time it became
effective, contained any untrue statement of a material fact or omitted to state
any material fact required to be stated therein or necessary in order to make
the statements therein, in the light of the circumstances under which they were
made, not misleading or that the Prospectus (except with respect to the
financial statements, schedules and other financial data included therein, as to
which we make no


                                     - 38 -

<PAGE>

statement), as of its date, and as of the date hereof, contains any untrue
statement of a material fact or omits to state any material fact necessary in
order to make the statements therein, in the light of the circumstances under
which they were made, not misleading.

                                     - 39 -