<PAGE>
                                                                   Exhibit 10.27



[CONFIDENTIAL TREATMENT REQUESTED] /*/ INDICATES MATERIAL THAT HAS BEEN OMITTED
AND FOR WHICH CONFIDENTIAL TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED
MATERIAL HAS BEEN FILED WITH THE SECURITIES AND EXCHANGE COMMISSION PURSUANT TO
RULE 406 PROMULGATED UNDER THE SECURITIES ACT OF 1933, AS AMENDED.
                                                                    CONFIDENTIAL


                              TERMINATION AGREEMENT



                              ELAN CORPORATION, PLC

                        ELAN PHARMA INTERNATIONAL LIMITED

                        ELAN INTERNATIONAL SERVICES, LTD.


                                 ACUSPHERE, INC.

                                       AND

                              ACUSPHERE NEWCO, LTD




<PAGE>




                                      INDEX
                                      -----
<TABLE>
<S>        <C>

CLAUSE 1   DEFINITIONS

CLAUSE 2   TERMINATION OF THE NEWCO AGREEMENTS

CLAUSE 3   REPRESENTATIONS/WARRANTIES/CONFIRMATONS AND INDEMNITIES

CLAUSE 4   INTELLECTUAL PROPERTY

CLAUSE 5   RIGHTS RELATED TO SECURITIES

CLAUSE 6   SALE OF SHARES AND COMPLETION

CLAUSE 7   CONFIDENTIALITY

CLAUSE 8   WAIVER OF ACCRUED RIGHTS / MUTUAL RELEASES

CLAUSE 9   PAYMENTS, REPORTS AND AUDITS

CLAUSE 10  GENERAL
</TABLE>




                                       2
<PAGE>






THIS TERMINATION AGREEMENT made this 26 day of September 2002 (this "AGREEMENT")

AMONG:-

(1)      ELAN CORPORATION, PLC, a public limited company incorporated under the
         laws of Ireland and having its registered office at Lincoln House,
         Lincoln Place, Dublin 2, Ireland ("ELAN CORP");

(2)      ELAN PHARMA INTERNATIONAL LIMITED, a private limited company
         incorporated under the laws of Ireland, and having its registered
         office at WIL House, Shannon Business Park, Shannon, County Clare,
         Ireland ("EPIL SHANNON");

(3)      ELAN INTERNATIONAL SERVICES, LTD., an exempted limited liability
         company incorporated under the laws of Bermuda, and having its
         registered office at Clarendon House, 2 Church St., Hamilton, Bermuda
         ("EIS");

(4)      ACUSPHERE, INC. a Delaware corporation having its principal place of
         business at 500 Arsenal Street, Watertown, Massachusetts, United States
         of America; and

(5)      ACUSPHERE NEWCO, LTD., an exempted company incorporated under the laws
         of Bermuda, and having its registered office at Clarendon House, 2
         Church St., Hamilton, Bermuda.

RECITALS:
--------

A.       The Parties entered into various agreements whereby Elan Corp, EPIL
         Shannon, EIS and JVP established the joint venture company, Newco, and
         Elan Corp, EPIL Shannon and JVP each licensed certain intellectual
         property to Newco for a specified field of use. Specifically:

         (i)      Elan Corp, EIS, EPIL Shannon, JVP and Newco entered into a
                  Subscription, Joint Development and Operating Agreement dated
                  30 June 2000 (the "JDOA");

         (ii)     Elan Corp, EPIL Shannon and Newco entered into a License
                  Agreement dated 30 June 2000 (the "ELAN LICENSE AGREEMENT");

         (iii)    JVP and Newco entered into a License Agreement dated 30 June
                  2000 (the "JVP LICENSE Agreement"); and



<PAGE>

         Newco, JVP and EIS entered into a Registration Rights Agreement with
         respect to the capital stock of Newco dated 30 June 2000 (the "NEWCO
         REGISTRATION RIGHTS AGREEMENT").

B.       The JDOA, Elan License Agreement, JVP License Agreement and Newco
         Registration Rights Agreement, are together defined in this Agreement
         as the "NEWCO AGREEMENTS".

C.       The Parties also entered into agreements whereby JVP sold and EIS
         purchased certain securities of JVP and the Parties agreed to certain
         matters related to the ownership of such securities. Specifically:

         (i)      EIS and JVP entered into a Securities Purchase Agreement dated
                  30 June 2000 (the "SECURITIES PURCHASE AGREEMENT") providing,
                  in part, for the issuance by JVP to EIS of that certain
                  Convertible Subordinated Promissory Note due June 30, 2006 in
                  the maximum aggregate principal amount of $8,010,000 (the
                  "PROMISSORY NOTE"), 1,232,308 shares of JVP's Series G
                  Non-Voting Convertible Preferred Stock, $.01 par value per
                  share (the "SERIES G PREFERRED STOCK"), and 1,127,819 shares
                  of JVP's Series H Convertible Preferred Stock, $.01 par value
                  per share (the "SERIES H PREFERRED STOCK");

         (ii)     JVP and EIS entered into an Exchange Agreement on 30 June 2000
                  (the "NEWCO EXCHANGE AGREEMENT");

         (iii)    JVP, EIS, and other Shareholders as listed therein entered
                  into a Sixth Amended and Restated Investors' Rights Agreement
                  with respect to the capital stock of JVP dated 30 June 2000,
                  which agreement has been amended and restated from time to
                  time thereafter (as amended, the "JVP REGISTRATION RIGHTS
                  AGREEMENT"); and

         (iv)     JVP, the Founders (as listed therein) and the Investors (as
                  listed therein and one of whom is EIS) entered into a Fifth
                  Amended and Restated Co-Sale Agreement dated 30 June 2000,
                  which agreement has been amended and restated from time to
                  time thereafter (as amended, the "CO-SALE Agreement").

D.       Pursuant to the terms of that certain Assignment and Assumption
         Agreement and related Bill of Sale each dated as of 1 January 2001 (the
         "NOTE ASSIGNMENT AGREEMENT"), EIS sold, transferred, assigned and set
         over all of its right, title and interest in, to and under the
         Promissory Note (but EIS retained the conversion rights contained
         therein) to EPIL Shannon.

E.       Pursuant to the terms of that certain Assignment and Assumption
         Agreement and related Bill of Sale each dated as of 15 March 2001 (the
         "SHARE ASSIGNMENT

                                       2
<PAGE>

         AGREEMENTS"), EIS sold, transferred, assigned and set over all of its
         right, title and interest in, to and under (i) all of its shares of
         Series G Preferred Stock and Series H Preferred Stock; (ii) the Newco
         Exchange Agreement; (iii) the JVP Registration Rights Agreement; (iv)
         the Co-Sale Agreement; and (v) Sections 3, 4(e), 7, 8, 9, 10, 11, 12,
         13, 14, 15, 16 and 17 (relating to representations, indemnification and
         sundry clauses) of the Securities Purchase Agreement (without limiting
         EIS's rights and benefits under the Securities Purchase Agreement or
         expanding the obligations of JVP thereunder), to ELAN PHARMACEUTICALS
         INVESTMENT III, LTD. an exempted limited liability company incorporated
         under the laws of Bermuda ("EPIL III").

F.       Pursuant to the terms of that certain Assignment and Assumption
         Agreement and related Bill of Sale each dated as of 1 July 2002 (the
         "EPIL III ASSIGNMENT AGREEMENT"), EPIL III sold, transferred, assigned
         and set over all of its right, title and interest in, to and under (i)
         all of its shares of Series G Preferred Stock and Series H Preferred
         Stock; (ii) the Newco Exchange Agreement; (iii) the JVP Registration
         Rights Agreement; (iv) the Co-Sale Agreement; and (v) Sections 3, 4(e),
         7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17 (relating to
         representations, indemnification and sundry clauses) of the Securities
         Purchase Agreement (without limiting EIS's rights and benefits under
         the Securities Purchase Agreement or expanding the obligations of JVP
         thereunder), to Shelly Bay Holdings, Ltd., ("SHELLY BAY").

G.       Pursuant to Clause 2.3 of the JDOA, the parties thereto initially
         nominated as a Compound, [CONFIDENTIAL TREATMENT REQUESTED] /*/, for
         administration via the pulmonary route for local effect and controlled
         release using a Mode of Administration (other than [CONFIDENTIAL
         TREATMENT REQUESTED] /*/) to treat asthma [CONFIDENTIAL TREATMENT
         REQUESTED] /*/ (the "FIRST R&D PROGRAM").

         Pursuant to Clause 2.6 of the JDOA, the parties thereto terminated all
         of Newco's activities in relation to the First R&D Program.

         Pursuant to Clause 2.6 of the JDOA, the parties thereto nominated as a
         substitute Compound, [CONFIDENTIAL TREATMENT REQUESTED] /*/, for
         administration via the pulmonary route for local effect and controlled
         release using a Mode of Administration (other than [CONFIDENTIAL
         TREATMENT REQUESTED] /*/) to treat asthma [CONFIDENTIAL TREATMENT
         REQUESTED] /*/ (the "SECOND R&D PROGRAM"). No written agreement was
         executed by the Parties to give effect to the nomination of the
         substitute Compound or the commencement of the Second R&D Program.

H.       The Parties wish to (i) terminate in full the Newco Agreements as set
         forth below, (ii) terminate the Securities Purchase Agreement solely as
         it relates to the Parties

                                       3
<PAGE>

         and (iii) set forth their agreement in relation to other matters
         including, inter alia, the transfer of shares by EIS to JVP.


IN CONSIDERATION OF THE MUTUAL COVENANTS CONTAINED HEREIN, AND OTHER GOOD AND
VALUABLE CONSIDERATION, THE RECEIPT AND ADEQUACY OF WHICH ARE HEREBY
ACKNOWLEDGED, IT IS HEREBY AGREED AS FOLLOWS:

1        DEFINITIONS:

         CAPITALISED TERMS USED IN THIS AGREEMENT SHALL HAVE THE SAME MEANINGS
         ASSIGNED TO THEM IN THE NEWCO AGREEMENTS, UNLESS SUCH TERMS ARE
         EXPRESSLY DEFINED TO THE CONTRARY IN THIS AGREEMENT.

         "AFFILIATE" shall mean any corporation or entity controlling,
         controlled or under the common control of any other corporation or
         entity, excluding, in the case of Elan Corp, an Elan JV. For the
         purpose of this definition, (i) "control" shall mean direct or indirect
         ownership of fifty percent (50%) or more of the stock or shares
         entitled to vote for the election of directors; and (ii) Newco shall
         not be an Affiliate of Elan Corp or EIS. EPIL III is not an Affiliate
         of Elan Corp.

         "ACUSPHERE [CONFIDENTIAL TREATMENT REQUESTED] /*/ PRODUCT PATENTS"
         shall mean the patent applications and/or patents, now existing or
         currently pending and set forth in Schedule 5, together with the patent
         applications and/or patents hereafter filed or obtained by JVP within
         six months from the Effective Date which result from inventions
         discovered pursuant to the Project (such patent applications and
         patents to be included on Schedule 5 by JVP six months following the
         Effective Date), and any foreign counterparts thereof and all
         divisionals, continuations, continuations-in-part (to the extent that
         there is subject matter claimed in the continuations-in-part
         developedpursuant to the Project), any foreign counterparts thereof and
         all patents issuing on any of the foregoing and any foreign
         counterparts thereof, together with all registrations, reissues,
         re-examinations, supplemental protection certificates, or extensions
         thereof, and any foreign counterparts thereof.

         "ACUSPHERE COMPETITOR" shall mean a Person (or Affiliate thereof) which
         manufactures, markets or sells (or licenses the right to manufacture,
         market or sell), or actively engages in research and development of,
         products designed to treat asthma [CONFIDENTIAL TREATMENT REQUESTED]
         /*/.

         "AGREED COST DEDUCTIONS" shall mean the sum of $3,701,131 and any
         research and development costs, clinical trial costs, clinical trial
         manufacturing costs and/or regulatory costs (where such work is carried
         out by JVP and/or Newco, charged at cost without the addition of any
         profit margin) incurred by Newco

                                       4
<PAGE>

         and/or JVP directly related to the development of the [CONFIDENTIAL
         TREATMENT REQUESTED] /*/ Product between September 1, 2002 and the Date
         of Commercialization.

         "BALANCE SHEET" shall mean the unaudited balance sheet of Newco made up
         to the Balance Sheet Date, as set forth in Schedule 3.4.

         "BALANCE SHEET DATE" shall mean 30 June 2002.

         "[CONFIDENTIAL TREATMENT REQUESTED] /*/ PRODUCT" shall mean a
         formulation of [CONFIDENTIAL TREATMENT REQUESTED] /*/ for
         administration via the pulmonary route for local effect and controlled
         release using a Mode of Administration (other than [CONFIDENTIAL
         TREATMENT REQUESTED] /*/) to treat asthma [CONFIDENTIAL TREATMENT
         REQUESTED] /*/ . For the avoidance of doubt, the [CONFIDENTIAL
         TREATMENT REQUESTED] /*/ Product does not comprise, or incorporate in
         any way, any intellectual property of Elan.

         "[CONFIDENTIAL TREATMENT REQUESTED] /*/ PRODUCT" shall mean a
         formulation of [CONFIDENTIAL TREATMENT REQUESTED] /*/ for
         administration via the pulmonary route for local effect and controlled
         release using a Mode of Administration (other than [CONFIDENTIAL
         TREATMENT REQUESTED] /*/) to treat asthma [CONFIDENTIAL TREATMENT
         REQUESTED] /*/, the manufacture, use or sale of which would infringe a
         valid claim under the Acusphere [CONFIDENTIAL TREATMENT REQUESTED] /*/
         Product Patents. For the avoidance of doubt, the [CONFIDENTIAL
         TREATMENT REQUESTED] /*/ Product does not comprise, or incorporate in
         any way, any intellectual property of Elan.

         "COMMERCIALIZATION AGREEMENT" shall mean:

         (i)      any license agreement, research and development agreement, or
                  alternate form of collaboration or commercialisation agreement
                  such as, but not limited to, a co-promotion or co-marketing
                  arrangement to research, develop, import, make, use, offer for
                  sale and/or sell the [CONFIDENTIAL TREATMENT REQUESTED] /*/
                  Product; or

         (ii)     any Disposal Agreement; or

         (ii)     an agreement comprising an option to do any of the foregoing.

         "CPI" shall mean the Consumer Price Index for all Urban Consumers, U.S.
         City Average published by the Bureau of Labor Statistics of the United
         States Department of Labor, or any successor index thereof.


                                       5
<PAGE>

         "CPI PERCENTAGE" shall mean a percentage equal to the percentage yearly
         increase in the CPI as of January 1 of each calendar year.

         "DATE OF COMMERCIALIZATION" shall mean the date of closing by JVP
         and/or Newco and any third party of a Commercialization Agreement.

         "DEFERRED CONSIDERATION" shall have the meaning set forth in Clause
         6.4.

         "DEFERRED CONSIDERATION PERIOD" shall mean the period commencing on the
         Effective Date and expiring on a Sub-Territory by Sub-Territory basis:

         (i)      on the 15th anniversary of the date of the first commercial
                  sale of the [CONFIDENTIAL TREATMENT REQUESTED] /*/ Product in
                  the Sub-Territory concerned, provided that in the case of
                  Europe, this 15 year period shall run from the date of the
                  first commercial sale of the [CONFIDENTIAL TREATMENT
                  REQUESTED] /*/ Product in any of the Major European Markets;
                  or

         (ii)     in any Sub-Territory upon the expiration of the life of the
                  last to expire of any Acusphere [CONFIDENTIAL TREATMENT
                  REQUESTED] /*/ Product Patent in that Sub-Territory;

         whichever date is later to occur.

         "DISPOSAL AGREEMENT" shall mean any agreement for the assignment or
         outright sale or disposition of all of JVP and/or Newco's intellectual
         property rights in the [CONFIDENTIAL TREATMENT REQUESTED] /*/ Product
         (other than to an Affiliate), but excluding the sale of JVP as a whole
         (whether by merger, stock sale, consolidation, reorganisation, sale of
         all or substantially all of its assets or other similar event).

         "EFFECTIVE DATE" shall mean the date of this Agreement.

         "EIS SHARES" shall have the meaning set forth in Clause 3.3.

         "ELAN" shall mean Elan Corp and its Affiliates, including without
         limitation, EPIL Shannon and EIS.

         "ELAN IMPROVEMENTS" shall mean improvements to the Elan Patents and/or
         the Elan Know-How, developed (i) by Elan outside the Project, (ii) by
         Elan, JVP or Newco or by a third party (under contract with Newco, Elan
         or JVP) pursuant to the Project, and/or (iii) jointly by any
         combination of Elan, JVP, Newco or a third party (under contract with
         Newco, Elan or JVP) pursuant to the Project.


                                       6
<PAGE>

         "ELAN JV" shall mean an entity that Elan and a third party (i)
         establish or have established; (ii) take shareholdings in or have a
         right to take shareholdings in; and (iii) grant certain licenses in and
         to certain intellectual property rights for the purpose of implementing
         a strategic alliance.

         "ELAN KNOW-HOW" shall have the meaning set forth in the Elan License
         Agreement.

         "ELAN PATENTS" shall have the meaning set forth in the Elan License
         Agreement.

         "ELAN TRADEMARK" shall mean all trade names or trademarks of Elan,
         registered or unregistered, now existing under applicable law.

         "FDA" shall mean the United States Food and Drug Administration or any
         other successor agency.

         "FORCE MAJEURE" shall mean causes beyond a Party's reasonable control,
         including, without limitation, acts of God, fires, strikes, acts of
         terrorism or war (whether war be declared or not), or intervention of a
         governmental authority.

         "FTE RATE" shall mean Full Time Equivalent Employee Rate, equaling
         $250,000 per full time equivalent ("FTE") per year on the Effective
         Date, an FTE being the equivalent of 1880 hours per year per employee,
         to be increased on January 1 of each calendar year after the Effective
         Date by an amount equal to (i) the then current FTE Rate multiplied by
         (ii) the CPI Percentage.

         "INITIAL CONSIDERATION" shall have the meaning set forth in Clause
         6.1.2.

         "IN MARKET" shall mean the sale of the [CONFIDENTIAL TREATMENT
         REQUESTED] /*/ Product by Newco and/or JVP to an unaffiliated third
         party, such as a wholesaler, managed care organization, hospital or
         pharmacy in the Territory, and shall exclude the transfer pricing of
         the [CONFIDENTIAL TREATMENT REQUESTED] /*/ Product by one Affiliate of
         Newco and/or JVP to another Affiliate of Newco and/or JVP.

         "JVP" shall mean Acusphere, Inc. and its Affiliates.

         "JVP IMPROVEMENTS" shall mean improvements to the JVP Patents and/or
         the JVP Know-How, developed (i) by JVP outside the Project, (ii) by
         JVP, Elan or Newco or by a third party (under contract with Newco, Elan
         or JVP) pursuant to the Project, and/or (iii) jointly by any
         combination of JVP, Elan, Newco or a third party (under contract with
         Newco, Elan or JVP) pursuant to the Project.

         "JVP KNOW-HOW" shall mean Acusphere Know-How (as such term is defined
         in the JVP License Agreement).


                                       7
<PAGE>

         "JVP PATENTS" shall mean Acusphere Patents (as such term is defined in
         the JVP License Agreement).

         "JVP TRADEMARKS" shall mean all trade names or trademarks of JVP,
         registered or unregistered, now existing under applicable law.

         "MAJOR EUROPEAN MARKETS" shall mean Spain, UK, Germany, Italy and
         France.

         "NDA" shall mean a New Drug Application, or any comparable successor
         form of application, filed with the FDA, including any supplements or
         amendments thereto which may be filed.

         "NET MANUFACTURING PROFITS" shall mean any payment realized by JVP or
         Newco upon the supply or sale of the [CONFIDENTIAL TREATMENT REQUESTED]
         /*/ Product to its partner in connection with a Commercialization
         Agreement in excess of the cost of goods sold for the [CONFIDENTIAL
         TREATMENT REQUESTED] /*/ Product, based on the cost of goods sold
         calculation set forth in the relevant Commercialization Agreement (if
         such is contained therein), or in the absence of such a calculation
         therein, consistent with JVP's cost of goods sold calculation for all
         similar third party dealings used for the purposes of JVP's audited
         financial statements, as determined in accordance with generally
         accepted U.S. accounting principles.

         "NET REVENUES" shall mean:

         (i)      all license fees, license option payments (whether in relation
                  to the grant or exercise of any license option), sublicense
                  fees, milestone payments, royalties on sales of the
                  [CONFIDENTIAL TREATMENT REQUESTED] /*/ Product, and any other
                  kinds of revenue whatsoever received by Newco or JVP in
                  respect of the commercialization of the [CONFIDENTIAL
                  TREATMENT REQUESTED] /*/ Product; and

         (ii)     any Net Manufacturing Profits realized by Newco or JVP;

         (iii)    any consideration received by Newco or JVP in respect under
                  any Disposal Agreement;

         (iv)     research and development payments received by Newco or JVP in
                  relation to research and development of the [CONFIDENTIAL
                  TREATMENT REQUESTED] /*/ Product, where such payments are made
                  other than for reimbursement of direct expenses incurred by
                  Newco or JVP, and where such payments are made other than on
                  the FTE Rate, the aggregate excess over the FTE Rate;


                                       8
<PAGE>

         (v)      any premium paid by a subscriber for stock of JVP and/or Newco
                  in connection with any Commercialization Agreement; provided
                  that the premium shall be defined as follows:

                  (1)    where JVP and/or Newco is not publicly listed on a
                         recognised stock exchange, the premium paid over the
                         fair market value of such stock as reasonably
                         determined by the board of directors of JVP and/or
                         Newco in good faith and certified in a board
                         resolution, taking into account (i) the most recently
                         or concurrently completed arm's length transaction in
                         which the primary consideration for the stock is cash
                         between the JVP or Newco and an unaffiliated third
                         party that is not part of a strategic investment and
                         the closing of which occurs within the six months
                         preceding or on the date of such calculation, if any),
                         (ii) the general market conditions for private biotech
                         securities, and (iii) the general state of progress in
                         clinical and commercial activities in JVP and/or Newco;
                         or

                  (2)    where JVP and/or Newco is publicly listed on a
                         recognised stock exchange, the premium paid over the
                         average closing price of such stock of JVP and/or Newco
                         for the 30 trading day period immediately prior to any
                         such subscription;

         provided that the amounts calculated pursuant to paragraphs (i) to (v)
         above shall be reduced by:

         (i)      deductions in respect of any customs and excise duties or
                  other sales taxes (but (for the avoidance of doubt) not income
                  or corporation tax), directly related to the receipt of
                  revenue by by Newco and/or JVP, as set out above; and

         (ii)     the Agreed Cost Deductions.

         "NET SALES" shall mean that sum determined, in accordance with
         generally accepted U.S. accounting principles, by deducting the
         following deductions from the aggregate gross In Market sales proceeds
         billed for the [CONFIDENTIAL TREATMENT REQUESTED] /*/ Product in the
         Territory by Newco and/or JVP or its Affiliate, as the case may be:

         (i)      customs and excise duties or other sales taxes (but (for the
                  avoidance of doubt) not income or corporation tax), directly
                  related to the sale of the [CONFIDENTIAL TREATMENT REQUESTED]
                  /*/ Product in the Territory which are actually paid by Newco
                  and/or JVP;

         (ii)     a discount from the gross sales proceeds to cover such normal
                  costs as are incurred by Newco and/or JVP in respect of
                  industry standard transport,

                                       9
<PAGE>

                  shipping and insurance costs; and industry standard or
                  mandatory discounts or rebates directly related to the sale of
                  the [CONFIDENTIAL TREATMENT REQUESTED] /*/ Product in the
                  Territory;

         (iii)    amounts repaid or credited by Newco and/or JVP consistent with
                  its normal business practices for similar products, by reason
                  of the rejection or return of goods.

         "NEWCO" shall mean Acusphere Newco, Ltd. and its Affiliates.

         "NEWCO INTELLECTUAL PROPERTY" shall mean have the meaning set forth in
         the JDOA.

         "NEWCO TRADEMARK" shall mean "Acusphere Newco, Ltd."

         "PARTY" shall mean Elan Corp, EPIL Shannon, EIS, JVP or Newco, as the
         case may be, and "PARTIES" shall mean all such parties together.

         "PRODUCTS" shall mean [CONFIDENTIAL TREATMENT REQUESTED] /*/ Product
         and [CONFIDENTIAL TREATMENT REQUESTED] /*/ Product.

         "PROJECT" shall have the meaning set forth in the JDOA, and shall
         include without limitation both the First R&D Program and the Second
         R&D Program.

         "SECURITIES ACT" shall have the meaning set forth in Clause 3.11.

         "SUB-TERRITORY" shall mean each of North America, Europe and Japan

         "TERRITORY" shall mean all of the Sub-Territories together.

         "UNITED STATES DOLLAR" and "US$" and "$" shall mean the lawful currency
         of the United States of America.


2        TERMINATION OF THE NEWCO AGREEMENTS

         2.1      Subject to the provisions of Clause 2.2 hereof, the Parties
                  hereby agree to terminate the Newco Agreements, including
                  without limitation, those provisions expressly stated to
                  survive termination, in each case with effect from the
                  Effective Date.

                  All the provisions of the Newco Agreements shall terminate
                  forthwith with effect from the Effective Date and be of no
                  further legal force or effect.


                                       10
<PAGE>

         2.2      For the avoidance of doubt and without prejudice to the
                  generality of the foregoing Clause 2.1, the Parties hereby
                  acknowledge and agree as follows as of the Effective Date:

                  2.2.1     the Management Committee and the R&D Committee (as
                            such terms are defined in the JDOA) shall each be
                            dissolved forthwith with effect from the Effective
                            Date and thereby cease to have any function;

                  2.2.2     the EIS Director, Kevin Insley, and his alternate
                            director, Debra Moore Buryj, holding office with
                            Newco immediately prior to the Effective Date shall
                            resign as directors of Newco;

                  2.2.3     the nominees on the Management Committee of Elan
                            shall be deemed to have been removed from the
                            Management Committee by Elan immediately prior to
                            the dissolution of the Management Committee pursuant
                            to Clause 2.2.1;

                  2.2.4     the nominees on the R&D Committee of Elan shall be
                            deemed to have been removed from the R&D Committee
                            by Elan immediately prior to the dissolution of the
                            Management Committee pursuant to Clause 2.2.1;

                  2.2.5     all rights granted to Newco pursuant to the Elan
                            License Agreement to use the Elan Patents, the Elan
                            Know-How and the Elan Improvements shall terminate
                            forthwith;

                  2.2.6     with effect from the Effective Date, neither JVP nor
                            Newco shall have any rights in or to the Elan
                            Patents, the Elan Know-How and/or the Elan
                            Improvements and/or any other patents, know-how or
                            any other intellectual property rights whatsoever of
                            Elan;

                  2.2.7     with effect from the Effective Date, Elan shall not
                            have any rights in or to the JVP Patents, the JVP
                            Know-How and/or the JVP Improvements and/or any
                            other patents, know-how or any other intellectual
                            property rights whatsoever of JVP;

                  2.2.8     Elan shall terminate or shall cause to be terminated
                            any and all research and development work being
                            conducted in connection with or pursuant to any
                            Research and Development Program of Newco, the Newco
                            Agreements, or otherwise on behalf of Newco;

                  2.2.9    the Parties shall terminate or cause to be terminated
                           all technical services and assistance (if any) being
                           conducted in connection with the Newco Agreements;


                                       11
<PAGE>

                  2.2.10   none of the Parties shall have any obligation to
                           provide working capital, research or development
                           funding, or other funding or financing of any nature
                           to Newco;

                  2.2.11   Elan shall not have any obligation to pay any
                           milestone payment or make any milestone investment to
                           or in Newco or JVP whether relating to the Project,
                           the achievement of any objectives set forth therein
                           or otherwise.

         2.3      Each of the Parties acknowledges and agrees with the other
                  Parties that, as of the Effective Date, no monies are owed or
                  are refundable by any of the Parties to the others pursuant to
                  the Newco Agreements, and any amounts shown as owing by Newco
                  to Elan and/or JVP on the Balance Sheet as of the Balance
                  Sheet Date are, as of the Effective Date, hereby deemed
                  forgiven and extinguished in all respects by Elan and/or JVP
                  respectively.

                  For the avoidance of doubt, the Parties acknowledge that Newco
                  is liable to pay any fees which are due and owing to Codan
                  Corporate Administrative Services upon the Effective Date and
                  which are disclosed on Schedule 2.3, or which become due and
                  owing thereafter.

                  For the avoidance of doubt, this Clause 2.3 does not in any
                  way negate or affect the provisions of Clause 6.4 (which
                  relates to the Deferred Consideration).


3        REPRESENTATIONS, WARRANTIES, CONFIRMATIONS AND INDEMNITIES

         3.1      SUB-LICENSES:

                  Each of the Parties acknowledges and agrees that Newco has not
                  granted any sub-licenses or any other rights of any nature to
                  any third parties relating to intellectual property rights
                  held by Newco pursuant to the Elan License Agreement or the
                  JVP License Agreement.

         3.2      JVP SHARES:

                  JVP represents and warrants to the other Parties that it is
                  the legal and beneficial owner of (i) 6,000 Common Shares (as
                  defined in the JDOA) and (ii) 3,612 Preferred Shares (as
                  defined in the JDOA).


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<PAGE>

         3.3      EIS SHARES:

                  EIS represents and warrants to the other Parties that it is
                  the legal and beneficial owner of 2,388 Preferred Shares (the
                  "EIS SHARES").

         3.4      BALANCE SHEET:

                  JVP represents and warrants to the other Parties that, to
                  JVP's knowledge, the Balance Sheet is accurate and that, since
                  the Balance Sheet Date, there has been no material adverse
                  change in the financial position or prospects of Newco.

                  JVP represents and warrants to the other Parties that, to
                  JVP's knowledge, as of the Effective Date, there are no other
                  creditors of Newco other than as described in the Balance
                  Sheet.

         3.5      THIRD PARTY AGREEMENTS / ORDERS / CLAIMS:

                  3.5.1    Each of the Parties represents and warrants to the
                           other Parties that, as of the Effective Date, to its
                           actual knowledge, Newco is not a party to, or bound
                           by, any judgment, order, decree or other directive of
                           or stipulation with any court or any governmental or
                           regulatory authority.

                  3.5.2    JVP represents and warrants to the other Parties
                           that, to its actual knowledge, Newco is not a party
                           to, or bound by, or is a third party beneficiary of
                           any agreement with any third party ("NEWCO THIRD
                           PARTY AGREEMENT(s)").

                           For the avoidance of doubt and with reference to the
                           indemnity in Clause 3.8.1, the Parties agree that the
                           indemnity in Clause 3.8.1 shall extend to any claims,
                           losses, liabilities or damages arising from such
                           Newco Third Party Agreements, in the event that the
                           representation and warranty in Clause 3.5.2 were to
                           be inaccurate..

                  3.5.3    Each of the Parties represents and warrants to the
                           other Parties that, as of the Effective Date, to its
                           actual knowledge, there are no claims, suits or
                           proceedings pending or threatened against Newco.

         3.6      REGULATORY APPLICATIONS:

                  Each of the Parties represents and warrants to the other
                  Parties that, to its actual knowledge, prior to and as of the
                  Effective Date, no regulatory applications have been filed by
                  Newco or by any Party with any government authority in any
                  part of the world for any of the Products,

                                       13
<PAGE>

                  Newco Intellectual Property, or otherwise howsoever in
                  relation to the Project.

         3.7      EXCLUSION OF WARRANTIES / LIABILITY:

                  WITH REFERENCE TO THE TRANSFER BY EIS TO JVP OF THE EIS SHARES
                  AS PROVIDED BY CLAUSE 6 ON THE EFFECTIVE DATE (BUT WITHOUT
                  PREJUDICE TO EIS' REPRESENTATIONS AND WARRANTIES EXPRESSLY
                  MADE HEREIN, INCLUDING WITHOUT LIMITATION EIS' REPRESENTATION
                  AND WARRANTY UNDER CLAUSE 3.3 HEREOF AS TO ITS LEGAL AND
                  BENEFICIAL OWNERSHIP OF THE EIS SHARES AND ITS OBLIGATION
                  UNDER CLAUSE 6.1.1 HEREOF TO TRANSFER THE EIS SHARES TO JVP
                  FREE FROM ALL LIENS, CHARGES AND ENCUMBRANCES), THE PARTIES
                  ACKNOWLEDGE AND AGREE THAT EIS AND ITS AFFILIATES MAKE NO
                  REPRESENTATION OR WARRANTY OF ANY NATURE TO JVP OR ANY OTHER
                  PERSON IN RELATION TO NEWCO OR ANY OF ITS AFFAIRS PAST,
                  PRESENT OR FUTURE.

                  JVP ACKNOWLEDGES THAT IT IS ENTERING INTO THIS AGREEMENT IN
                  RELIANCE EXCLUSIVELY ON ITS OWN BUSINESS JUDGEMENT, THE
                  INFORMATION WHICH HAS BEEN AVAILABLE TO IT AS A SHAREHOLDER OF
                  NEWCO AND OTHERWISE AND ON THE DUE DILIGENCE IT HAS CARRIED
                  OUT IN RELATION TO NEWCO.

                  EXCEPT AS EXPRESSLY PROVIDED IN THIS AGREEMENT, ALL OTHER
                  WARRANTIES, CONDITIONS OR REPRESENTATIONS, EXPRESS OR IMPLIED,
                  STATUTORY OR OTHERWISE, ARE HEREBY EXPRESSLY EXCLUDED BY THE
                  PARTIES.

                  NOTWITHSTANDING ANYTHING TO THE CONTRARY IN THIS AGREEMENT, NO
                  PARTY SHALL BE LIABLE TO ANY OTHER PARTY BY REASON OF ANY
                  REPRESENTATION OR WARRANTY, CONDITION OR OTHER TERM OR ANY
                  DUTY OF COMMON LAW, OR UNDER THE EXPRESS TERMS OF THIS
                  AGREEMENT, FOR ANY CONSEQUENTIAL SPECIAL OR INCIDENTAL OR
                  PUNITIVE LOSS OR DAMAGE (WHETHER FOR LOSS OF CURRENT OR FUTURE
                  PROFITS, LOSS OF ENTERPRISE VALUE OR OTHERWISE) AND WHETHER
                  OCCASSIONED BY THE NEGLIGENCE OF THE RESPECTIVE PARTIES, THEIR
                  EMPLOYEES OR AGENTS OR OTHERWISE.


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<PAGE>

         3.8      INDEMNITY BY JVP ON ACTIVITIES OF NEWCO:

                  3.8.1    JVP hereby agrees to indemnify and hold harmless Elan
                           Corp, EIS and their respective Affiliates, officers,
                           directors, agents, representatives, employees and
                           shareholders, and any person holding office on or
                           prior to the Effective Date as an EIS Director (as
                           defined in the JDOA) (or any alternate director of
                           the EIS Director) or as a member of the Management
                           Committee or the R&D Committee (each such person or
                           entity referred to as an "INDEMNIFIED PARTY") against
                           any claims, losses, liabilities or damages and
                           expenses (including reasonable attorneys' fees and
                           expenses) reasonably incurred or sustained by such
                           Indemnified Party arising in relation to any claim or
                           proceedings made by third parties against an
                           Indemnified Party which relate in any way to the
                           activities of Newco, past present or future,
                           including without limitation, claims arising with
                           respect to the conduct of clinical trials (if any) by
                           Newco, or by JVP or any other person or entity on
                           behalf of Newco whether in connection with the
                           Project or otherwise.

                  3.8.2    For the avoidance of doubt and without prejudice to
                           the generality of Clause 3.8.1, JVP shall indemnify
                           and hold harmless Elan against any claims, losses,
                           liabilities or damages and expenses (including
                           reasonable attorneys' fees and expenses) which are
                           reasonably incurred and which may arise in relation
                           to any claim or proceedings made by third parties
                           against Elan Corp or any of its Affiliates alleging
                           infringement or other unauthorised use of the
                           proprietary rights of a third party arising from the
                           manufacture, importation, use, offer for sale, sale
                           or other commercialization of any of the Products and
                           the Newco Intellectual Property.

                  3.8.3    For the avoidance of doubt and with reference to the
                           indemnity in Clause 3.8.1, the Parties acknowledge
                           that a Phase 1 PK Analysis Clinical Trial was carried
                           out by the JVP on behalf of Newco with respect to the
                           development of the [CONFIDENTIAL TREATMENT REQUESTED]
                           /*/ Product and agree that the indemnity in Clause
                           3.8.1 shall extend to any claims, losses, liabilities
                           or damages arising from such Phase 1 PK Analysis
                           Clinical Trial.

                  3.8.4    Prior to or upon the Effective Date, JVP shall
                           furnish Elan Corp with copies of all policies of
                           comprehensive general liability insurance and/or
                           other insurance coverages (the "POLICIES") which

                                       15
<PAGE>

                           it holds in respect of the Phase 1 PK Analysis
                           Clinical Trial referred to in Clause 3.8.3.

                  3.8.5    Each of the Parties represents and warrants that, to
                           its actual knowledge, no clinical trials were carried
                           out with respect to the development of the
                           [CONFIDENTIAL TREATMENT REQUESTED] /*/.

                  3.8.6    Any Indemnified Party seeking indemnification
                           pursuant to this Clause 3.8 from or against the
                           assertion of any claim by a third person (an
                           "INDEMNIFICATION CLAIM") shall give prompt notice to
                           JVP; provided, however, that failure to give prompt
                           notice shall not relieve JVP of any liability
                           hereunder (except to the extent JVP has suffered
                           actual material prejudice by such failure).

                  3.8.7    Within thirty (30) days of receipt of notice from the
                           Indemnified Party pursuant to Clause 3.8.6, JVP shall
                           have the right exercisable by written notice to the
                           Indemnified Party to assume the defense of an
                           Indemnification Claim. If JVP assumes such defense,
                           JVP may select counsel to handle such defense. If JVP
                           does not assume the defense of any Indemnification
                           Claim in accordance with this Clause 3.8.7, then,
                           upon ten (10) days' written notice to JVP, the
                           Indemnified Party may assume the defense of the
                           Indemnification Claim. In such event, the Indemnified
                           Party shall be entitled under this Clause 3.8.7 as
                           part of its damages to indemnification for the costs
                           of such defense.

                  3.8.8    If JVP has been advised by the written opinion of
                           counsel to the Indemnified Party that the use of the
                           same counsel to represent both the Indemnified Party
                           and JVP would present a conflict of interest, then
                           the Indemnified Party may select its own counsel to
                           represent the Indemnified Party in the defense of the
                           matter and the costs of such defense shall be borne
                           by JVP. JVP shall be entitled to continue to handle
                           its own representation in such matter through its own
                           counsel.

                  3.8.9    The party controlling the defense of an
                           Indemnification Claim shall have the right to consent
                           to the entry of judgement with respect to, or
                           otherwise settle, the Indemnification Claim with the
                           prior written consent of the other party, which
                           consent shall not be unreasonably withheld.

                  3.8.10   JVP or the Indemnified Party, as the case may be,
                           shall cooperate in the defense or prosecution of any
                           Indemnification Claim. JVP or the Indemnified Party,
                           as the case may be, shall have the right to


                                       16
<PAGE>

                           participate, at its own expense, in the defense or
                           settlement of any Indemnification Claim.

                  3.8.11   FOR THE AVOIDANCE OF DOUBT, THE SOLE AND EXCLUSIVE
                           OBLIGATION OF JVP TO THE INDEMNIFIED PARTY FOR
                           INDEMNIFICATION CLAIMS ARISING UNDER THIS CLAUSE 3.8
                           OR CLAUSE 3.5.2 SHALL BE LIMITED TO THE
                           INDEMNIFICATION OBLIGATIONS SET FORTH IN THIS CLAUSE
                           3.8.

         3.9      ORGANIZATION AND AUTHORITY:

                  Each of the Parties represents and warrants to the other
                  Parties that it is a corporation duly organised and validly
                  existing under the laws of its jurisdiction of organisation
                  and has all the requisite corporate power and authority to
                  enter into this Agreement and to carry out the transactions
                  contemplated hereby.

         3.10     APPROVALS:

                  Except as set forth in Clause 6.3, each of the Parties
                  represents and warrants to the other Parties that no permit,
                  authorization, consent or approval of or by ("APPROVAL"), or
                  any notification of or filing with ("FILING"), any person or
                  entity (governmental or otherwse) is required in connection
                  with the execution, delivery or performance of this Agreement
                  by such Party, or if any such Approval or Filing is so
                  required, that same has been obtained or filed prior to the
                  Effective Date.

         3.11     NO CONFLICTS:

                  Each of the Parties represents and warrants to the other
                  Parties that, as of the Effective Date, the execution,
                  delivery and performance by such Party of this Agreement, and
                  the compliance with the provisions hereof by such Party, will
                  not:

                  3.11.1   violate any provision of applicable law, statute,
                           rule or regulation applicable to such Party or any
                           ruling, writ, injunction, order, judgment or decree
                           of any court, arbitrator, administrative agency or
                           other governmental body applicable to such Party or
                           any of its properties or assets;

                  3.11.2  conflict with or result in any breach of any of the
                          terms, conditions or provisions of, or constitute a
                          default, or give rise to any right of termination,
                          cancellation or acceleration under the charter or
                          organizational documents of such Party or any contract
                          to which

                                       17
<PAGE>

                           such Party is a party, except where such violation,
                           conflict or breach would not, individually or in the
                           aggregate, have a material adverse effect on such
                           Party.

         3.12     INVESTMENT REPRESENTATIONS:

                  JVP hereby represents and warrants to the other Parties that,
                  as of the Effective Date, (i) it is sophisticated in
                  transactions of this type and capable of evaluating the merits
                  and risks of its investment in Newco, (ii) it has not been
                  formed solely for the purpose of making this investment and is
                  acquiring the EIS Shares for investment for its own account,
                  not as a nominee or agent, and not with the view to, or for
                  resale in connection with, any distribution of any part
                  thereof, , (iii) it understands that the EIS Shares have not
                  been registered under the Securities Act of 1933, as amended
                  (the "SECURITIES ACT"), or applicable state and foreign
                  securities laws by reason of a specific exemption from the
                  registration provisions of the Securities Act and applicable
                  state and foreign securities laws, the availability of which
                  depends upon, among other things, the bona fide nature of the
                  investment intent and the accuracy of its representations as
                  expressed herein and (iv) it understands that no public market
                  now exists for any of the EIS Shares and that there is no
                  assurance that a public market will ever exist for such
                  shares.

         3.13     TRADEMARK APPLICATIONS:

                  Each of the Parties represents and warrants to the other
                  Parties that, to its actual knowledge, Newco has not filed for
                  any trademark protection or has not adopted any new trademark,
                  apart from the Newco Trademark, in connection with Newco's
                  business or any product or service provided thereunder.

         3.14     ACUSPHERE [CONFIDENTIAL TREATMENT REQUESTED] /*/ PRODUCT
                  PATENTS:

                  JVP hereby represents and warrants to Elan that JVP has
                  provided full and accurate disclosure in Schedule 5 of all
                  patents and patent applications filed or pending by JVP on the
                  Effective Date which cover the [CONFIDENTIAL TREATMENT
                  REQUESTED] /*/ Product.

         3.15     REPRESENTATIONS AND WARRANTIES AS OF THE EFFECTIVE DATE:

                  Except where expressly stated otherwise, each of the
                  representations and warranties in this Agreement are made as
                  of the Effective Date.


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<PAGE>

4        INTELLECTUAL PROPERTY

         4.1      OWNERSHIP:

                  On and following the Effective Date:

                  4.1.1    For the avoidance of doubt, the Elan Patents, the
                           Elan Know-How, the Elan Improvements and/ or the Elan
                           Trademarks shall remain the sole and exclusive
                           property of Elan.

                           Elan confirms that no Elan Improvements were
                           developed pursuant to the Project, or otherwise
                           pursuant to the Newco Agreements.

                  4.1.2    For the avoidance of doubt, the JVP Patents, the JVP
                           Know-How, the JVP Improvements and/or the JVP
                           Trademarks shall remain the sole and exclusive
                           property of JVP.

                  4.1.3    All Newco Intellectual Property shall remain the sole
                           and exclusive property of Newco.

                  4.1.4    A full list of the JVP Improvements and/or the Newco
                           Intellectual Property developed pursuant to the
                           Project, or otherwise pursuant to the Newco
                           Agreements is set forth in Schedule 4.1.

         4.2      For the avoidance of doubt, to the extent that Elan may have
                  any right to any intellectual property rights listed in
                  Schedule 4.1, Elan hereby assigns such intellectual property
                  rights to JVP on the Effective Date.


5        RIGHTS RELATED TO SECURITIES

         5.1      The Parties hereby agree to terminate the Securities Purchase
                  Agreement as between the parties, including without
                  limitation, those provisions expressly stated to survive
                  termination, with effect from the Effective Date.

         5.2      The Parties hereby agree to terminate and cancel the
                  Promissory Note, with effect from the Effective Date.

         5.3      All the provisions of the Securities Purchase Agreement as
                  between the Parties and the Promissory Note shall terminate
                  forthwith with effect from the Effective Date and be of no
                  further legal force or effect.

         5.4      Notwithstanding Clauses 5.1, 5.2 and 5.3 hereof, the Parties
                  acknowledge that Shelly Bay has the right, title and interest
                  in, to and under (i) the 2,517,448 shares of common stock of
                  JVP issued upon conversion of the

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<PAGE>

                  shares of Series G Preferred Stock and Series H Preferred
                  Stock transferred thereto (including the payment of
                  paid-in-kind dividends issuable in connection with such
                  conversion); (ii) the Newco Exchange Agreement; (iii) the JVP
                  Registration Rights Agreement; (iv) the Co-Sale Agreement; and
                  (v) Sections 3, 4(e), 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and
                  17 (relating to representations, indemnification and sundry
                  clauses) of the Securities Purchase Agreement.

         5.5      For the avoidance of doubt, Elan hereby represents and
                  warrants to the other Parties that it has assigned any and all
                  rights in or under the Newco Exchange Agreement to EPIL III
                  and that EPIL III has assigned any and all rights in or under
                  the Newco Exchange Agreement to Shelly Bay. The Parties hereby
                  acknowledge that JVP and Shelly Bay have terminated the Newco
                  Exchange Agreement as of the Effective Date pursuant to an
                  agreement between Shelly Bay and JVP. Accordingly, neither
                  Elan nor EPIL III and, to Elan's knowledge, neither Shelly Bay
                  nor any other party has any right, title or interest in or
                  under the Newco Exchange Agreement.


6        SALE OF SHARES AND COMPLETION

         6.1      Subject to the terms of this Agreement:

                  6.1.1    EIS shall sell as legal and beneficial owner and JVP
                           shall purchase, free from all liens, charges and
                           encumbrances and together with all rights now or
                           hereafter attaching to them, the EIS Shares;

                  6.1.2    the EIS Shares will be sold by EIS to JVP for a total
                           initial consideration of $10 (the "INITIAL
                           CONSIDERATION") and the Deferred Consideration.

         6.2      On the Effective Date, Elan and JVP shall take or (to the
                  extent that the same is within its powers) cause to be taken
                  the following steps prior to or at directors and shareholders
                  meetings of Newco, or such other meetings, as appropriate:

                  6.2.1    the delivery by EIS to JVP of a stock transfer form
                           in respect of the EIS Shares duly executed by EIS in
                           favour of JVP or as it may direct together with the
                           related share certificates;

                  6.2.2    the payment by JVP to EIS of the Initial
                           Consideration;

                  6.2.3    the transfer to JVP (or as it may direct) of the
                           share register, and all books and records of Newco in
                           the possession of Elan (including any minute books
                           and any company seal(s));


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<PAGE>

                  6.2.4    the change of the registered office of Newco from
                           Clarendon House, 2 Church St., Hamilton, Bermuda;

                  6.2.5    the resignation of the EIS Director on Newco's Board
                           of Directors and any alternate director of the EIS
                           Director as provided in Clause 2.2.2;

                  6.2.6    the adoption of new Bye-Laws of Newco;

                  6.2.7    the modification, as appropriate, by board
                           resolutions of Newco of matters such as the removal
                           of EIS as book keepers for Newco, the removal of EIS
                           representatives as authorised signatories of Newco's
                           bank account, the resignation of the Company
                           Secretary and any other related matters whatsoever;

                  6.2.8    any other steps required by this Agreement.

         6.3      JVP shall, prior to or on the Effective Date, notify the
                  Bermuda Monetary Authority of the transfer of the EIS Shares.

         6.4      DEFERRED CONSIDERATION:

                  In consideration of the sale by EIS to JVP of the EIS Shares
                  under Clause 6.1, JVP and its Affiliates (excluding Newco)
                  shall be jointly and severally liable to pay to EIS as
                  deferred consideration ("DEFERRED CONSIDERATION"):

                  6.4.1   if Newco and/or JVP sells the [CONFIDENTIAL TREATMENT
                          REQUESTED] /*/ Product In Market, 1% of Net Sales
                          during the Deferred Consideration Period; or

                  6.4.2   if Newco and/or JVP enters into a Commercialization
                          Agreement with any third party, 8% of Net Revenues in
                          the Territory during the Deferred Consideration
                          Period.


7        CONFIDENTIALITY

         7.1      CONFIDENTIALITY:

         7.1.1    The Parties agree that it may be necessary pursuant to this
                  Agreement, from time to time, to disclose to each other
                  confidential and proprietary information, including without
                  limitation, inventions, trade secrets, specifications,
                  designs, data, know-how and other proprietary information,


                                       21
<PAGE>

                  processes, services and business of the disclosing Party.

                  The foregoing together with the terms of this Agreement shall
                  be referred to collectively as "ADDITIONAL CONFIDENTIAL
                  INFORMATION".

                  The Parties also agree that it may have been necessary to
                  disclose to each other Confidential Information (as defined in
                  the JDOA) pursuant to the Newco Agreements.

                  Together Additional Confidential Information and Confidential
                  Information shall be referred to collectively as "PROPRIETARY
                  INFORMATION".

         7.1.2    Save as otherwise specifically provided herein, and subject to
                  Clause 7.2 and 7.3, each Party shall disclose Proprietary
                  Information of the other Party only to those employees,
                  representatives and agents requiring knowledge thereof in
                  connection with fulfilling the Party's obligations under this
                  Agreement, and not to any other third party.

                  Each Party further agrees to inform all such employees,
                  representatives and agents of the terms and provisions of this
                  Agreement relating to Proprietary Information and their duties
                  hereunder and to obtain their agreement hereto as a condition
                  of receiving Proprietary Information.

                  Each Party shall exercise the same standard of care as it
                  would itself exercise in relation to its own confidential
                  information (but in no event less than a reasonable standard
                  of care) to protect and preserve the proprietary and
                  confidential nature of the Proprietary Information disclosed
                  to it by the other Party.

                  Each Party shall promptly, upon request of the other Party,
                  return all documents and any copies thereof containing
                  Proprietary Information belonging to, or disclosed by, such
                  other Party, save that it may retain one copy of the same
                  solely for the purposes of ensuring compliance with this
                  Clause 7.

         7.1.3    Any breach of this Clause 7 by any person informed by one of
                  the Parties is considered a breach by the Party itself.

         7.1.4    Proprietary Information shall be deemed not to include:

                  (1)      information which is in the public domain;

                  (2)      information which is made public through no breach of
                           this Agreement;


                                       22
<PAGE>

                  (3)      information which is independently developed by a
                           Party, as evidenced by such Party's records;

                  (4)      information that becomes available to a receiving
                           Party on a non-confidential basis, whether directly
                           or indirectly, from a source other than the other
                           Party, which source did not acquire this information
                           on a confidential basis.

         7.1.5    The provisions relating to confidentiality in this Clause 7
                  shall remain in effect during the term of this Agreement, and
                  for a period of 10 years following the Effective Date of this
                  Agreement; provided, however, that, with respect to any
                  Proprietary Information which remains a "trade secret" under
                  applicable law, the provisions relating to confidentiality in
                  this Clause 7 with respect thereto shall survive for so long
                  as such information so remains a "trade secret".

         7.1.6    The Parties agree that the obligations of this Clause 7 are
                  necessary and reasonable in order to protect the Parties'
                  respective businesses, and each Party agrees that monetary
                  damages may be inadequate to compensate a Party for any breach
                  by the other Party of its covenants and agreements set forth
                  herein.

                  The Parties agree that any such violation or threatened
                  violation may cause irreparable injury to a Party and that, in
                  addition to any other remedies that may be available, in law
                  and equity or otherwise, each Party shall be entitled to seek
                  injunctive relief against the threatened breach of the
                  provisions of this Clause 7, or a continuation of any such
                  breach by the other Party, specific performance and other
                  equitable relief to redress such breach together with damages
                  and reasonable counsel fees and expenses to enforce its rights
                  hereunder.

         7.2      ANNOUNCEMENTS:

         7.2.1    Subject to Clause 7.3, no announcement or public statement
                  concerning the existence, subject matter or any term of this
                  Agreement shall be made by or on behalf of any Party without
                  the prior written approval of the other Party or Parties.

                  The terms of any such announcement shall be agreed in good
                  faith by the Parties.

                  Upon execution of this Agreement, JVP may issue a press
                  release in the form attached hereto as Schedule 7.2.1, and
                  thereafter the Parties shall be

                                       23
<PAGE>

                  permitted to make public statements consistent with the
                  content of such release.

         7.3      REQUIRED DISCLOSURES:

         7.3.1    A Party (the "DISCLOSING PARTY") will be entitled to make an
                  announcement or public statement concerning the existence,
                  subject matter or any term of this Agreement, or to disclose
                  Proprietary Information that the Disclosing Party is required
                  to make or disclose pursuant to:

                  (1)      a valid order of a court or governmental authority;
                           or

                  (2)      any other requirement of law or any securities or
                           stock exchange (including, without limitation, the
                           Securities Act);

                  provided that if the Disclosing Party becomes legally required
                  to make such announcement, public statement or disclosure
                  hereunder, the Disclosing Party shall give the other Party or
                  Parties prompt notice of such fact to enable the other Party
                  or Parties, if it (or they) so choose, to seek a protective
                  order or other appropriate remedy concerning any such
                  announcement, public statement or disclosure.

                  The Disclosing Party shall fully co-operate with the other
                  Party or Parties in connection with that other Party's or
                  Parties' efforts to obtain any such order or other remedy.

                  If any such order or other remedy does not fully preclude
                  announcement, public statement or disclosure, the Disclosing
                  Party shall make such announcement, public statement or
                  disclosure only to the extent that the same is legally
                  required.

         7.3.2    Each of the Parties shall be entitled to provide a copy of
                  this Agreement (and any subsequent amendments hereto) and the
                  Newco Agreements to a potential third party purchaser in
                  connection with Clause 10.2.1(2); or to any potential third
                  party investor(s) or lender(s) in the course of any financing
                  by any Party ; and EIS (and/or any Affiliate) shall also be
                  entitled to so provide in connection with Clause 10.2.2; and
                  JVP and/or Newco shall also be entitled to so provide to any
                  potential third party to any Commercialization Agreement
                  PROVIDED THAT the relevant third party purchaser, investor,
                  lender, assignee, or potential third party to any
                  Commercialization Agreement has entered into a confidentiality
                  agreement on terms no less protective than the terms of this
                  Clause 7.

                  Notwithstanding anything to the contrary contained
                  herein, the existence, subject matter and terms of
                  this Agreement may be disclosed on a non-

                                       24
<PAGE>

                           confidential basis if in connection with a public
                           offering of JVP's equity securities.


8        WAIVER OF ACCRUED RIGHTS/MUTUAL RELEASES

         8.1      With effect from the Effective Date, each Party and each of
                  its Affiliates ("RELEASOR"):-

                  8.1.1   waives any accrued rights that Releasor may have
                          accrued against the other Parties and each of its
                          Affiliates, officers, directors, representative,
                          agents and employees and the assigns and successors in
                          interest of any of the foregoing entities
                          ("RELEASEES"), whether known or unknown, foreseen or
                          unforeseen, fixed or contingent, of any nature
                          whatsoever from the beginning of time to the Effective
                          Date under the Newco Agreements; and

                  8.1.2   fully and finally releases and discharges the
                          Releasees from any and all manner of actions, claims,
                          promises, debts, sums of money, demands, obligations,
                          in law or in equity, directly or indirectly, whether
                          known or unknown, foreseen or unforeseen, fixed or
                          contingent, of any nature whatsoever that Releasor may
                          have by reason of any act, omission, matter,
                          provision, cause or thing whatsoever from the
                          beginning of time to the Effective Date under the
                          Newco Agreements.

         8.2      For the avoidance of doubt the provisions of this Clause 8
                  shall not in any way act as a waiver by any of the Parties in
                  respect of any of the provisions set forth in this Agreement
                  (including, for the avoidance of doubt, Clause 3.8.1
                  (Indemnity by JVP on future activities of Newco) and/or Clause
                  6.4 (Deferred Consideration)).


9        PAYMENTS, REPORTS AND AUDITS

9.1      With reference to Clause 6.4, Newco and/or JVP shall keep true and
         accurate records of Net Revenues or Net Sales and any deductibles made
         in calculating same for a period of three (3) years following the
         calendar quarter (or any part thereof) in which such Net Revenues or
         Net Sales occurred. Where Newco and/or JVP has Net Revenues or Net
         Sales, Newco and/or JVP shall deliver to EIS a written statement (the
         "STATEMENT") thereof within 45 days following the end of each calendar
         quarter (or any part thereof) in which such Net Revenues or Net Sales
         occurred. The financial officers of EIS and Newco and/or JVP shall
         agree upon the precise format of the Statement.


                                       25
<PAGE>

9.2      Payments due on Net Revenues or Net Sales on sales amounts in a
         currency other than US Dollars shall first be calculated in the foreign
         currency and then converted to US Dollars on the basis of the exchange
         rate in effect for the purchase of US Dollars with such foreign
         currency quoted in the Wall Street Journal (or comparable publication
         if not quoted in the Wall Street Journal) on the last business day of
         the calendar quarter in which such Net Revenues or Net Sales occurred.

9.3      Any income or other taxes which JVP and/or its Affiliates (excluding
         Newco) is required by law to pay or withhold on behalf of EIS with
         respect to such Net Revenues or Net Sales payments under this Agreement
         shall be deducted from the amount of such Net Revenues or Net Sales
         payments. JVP and/or its Affiliates (excluding Newco) shall furnish EIS
         as part of the Statement an accounting of any such payments. JVP and/or
         its Affiliates (excluding Newco) shall promptly provide EIS, upon
         request, with a certificate or other documentary evidence to enable EIS
         to seek a refund or a foreign tax credit with respect to any such tax
         so withheld or deducted by JVP and/or its Affiliates (excluding Newco).
         The parties will reasonably cooperate in completing and filing
         documents required under the provisions of any applicable tax treaty or
         under any other applicable law, in order to enable JVP and/or its
         Affiliates (excluding Newco) to make such payments to EIS without any
         deduction or withholding.

9.4      Payment of monies hereunder shall be made by JVP and/or its Affiliates
         (excluding Newco) to EIS within 45 days of the Statement.

         All payments due hereunder shall be made in U.S. Dollars.

9.5      All payments due hereunder shall be made to the designated bank account
         of EIS in accordance with such timely written instructions as EIS shall
         from time to time provide.

9.6      Without prejudice to EIS's other remedies hereunder, JVP and/or its
         Affiliates (excluding Newco) shall pay interest to EIS on sums not paid
         to EIS on the date on which payment should have been made pursuant to
         the applicable provisions of this Agreement ("DUE DATE") over the
         period from the Due Date until the date of actual payment (both before
         and after judgement) at the Prime Rate publicly announced by Morgan
         Guaranty Trust Company of New York at its principal office on the Due
         Date (or next to occur business day, if such date is not a business
         day) plus 3%, such interest to be payable on demand from time to time
         and compounded quarterly.

9.7      For the 180 day period following the close of each calendar year of the
         Agreement, JVP and/or its Affiliates (excluding Newco) will, in the
         event that EIS reasonably requests such access, provide independent
         certified accountants selected by EIS

                                       26
<PAGE>

         (other than independent certified accountants of record) (reasonably
         acceptable to JVP and/or its Affiliates (excluding Newco)) with access,
         during regular business hours and subject to the confidentiality
         provisions as contained in this Agreement, to JVP's and/or its
         Affiliates' (excluding Newco) books and records solely for the purpose
         of verifying the accuracy and reasonable composition of the
         calculations hereunder for the calendar year then ended.

         In addition, the independent certified accounts performing the
         inspection shall execute a confidentiality agreement reasonably
         acceptable to JVP, EIS and such accounting firm which shall limit the
         disclosure to EIS of confidential information disclosed to such
         accounting firm while performing such inspection solely to such
         information as is reasonably necessary to determine if JVP has complied
         with this Agreement, or if not, the amount and manner of any deficiency
         or surplus for the period reviewed.

9.8      Any such inspection of JVP's records shall be at the expense of EIS,
         except that if any such inspection reveals a deficiency in the amount
         of the Deferred Consideration actually paid to EIS hereunder in any
         calendar year quarter of five percent (5.0%) or more of the amount of
         any Deferred Consideration actually due to EIS hereunder, then the
         expense of such inspection shall be borne solely by JVP. If such
         inspection reveals a surplus in the amount of Deferred Consideration
         actually paid to EIS by JVP, EIS shall promptly reimburse JVP the
         surplus without interest.

9.9      JVP and/or Newco shall, promptly following the execution of any
         Commercialisation Agreement (and any subsequent amendment thereto),
         provide Elan with a copy of the financial provisions and any other
         relevant terms of such Commercialisation Agreement.

9.10     In the event that JVP and/or Newco shall enter into any
         Commercialisation Agreement with any third party, together with other
         products of JVP and/or Newco by the method commonly known in the
         pharmaceutical industry as "bundling" and the price attributable to the
         [CONFIDENTIAL TREATMENT REQUESTED] /*/ Product is less than the average
         price which would have been attributable thereto on an "arms length"
         basis, the Net Sales or Net Revenues attributable thereto hereunder
         shall be adjusted by the Parties to reflect an average price on an
         "arms length" basis.


                                       27
<PAGE>

10       GENERAL

10.1     GOVERNING LAW AND JURISDICTION:

         10.1.1   This Agreement shall be governed by and construed in
                  accordance with the internal laws of the State of New York
                  without regard to conflicts of law principles under the laws
                  of the State of New York.

         10.1.2   For the purposes of this Agreement, the Parties submit to the
                  nonexclusive jurisdiction of the State and Federal Courts of
                  New York.

10.2     ASSIGNMENT

         10.2.1   Subject to Clause 10.2.2 and Clause 10.2.3, this Agreement
                  shall not be assigned by any Party without the prior written
                  consent of the others, save that any Party:

                  (1)     may assign this Agreement in whole or in part and
                          delegate its duties hereunder to its Affiliate or
                          Affiliates without such consent; and

                  (2)     may assign its rights and obligations to a successor
                          (whether by merger, stock sale, consolidation,
                          reorganisation or other similar event) or purchaser of
                          all or substantially all of its assets relating to
                          such Party's technology related to this Agreement,
                          provided that such successor or purchaser has agreed
                          in writing to assume all of such Party's rights and
                          obligations hereunder and a copy of such assumption is
                          provided to the other Parties.

         10.2.2   EIS (and/or any Affiliate) shall be entitled to assign the
                  rights of EIS (or any Affiliate) to the Deferred Consideration
                  under Clause 6.4 and Clause 9 to any third party other than an
                  Acusphere Competitor without the consent of any other Party
                  hereto. EIS (and/or any Affiliate) shall promptly notify the
                  other Parties hereto of any such assignment identifying the
                  assignee, provided, however, that any payment of Deferred
                  Consideration by JVP to EIS (in accordance with the terms of
                  this Agreement) prior to the receipt of any such notice by JVP
                  hereunder shall constitute a good discharge of such payment
                  obligation against the assignee.

10.3     NOTICES

         10.3.1   Any notice to be given under this Agreement shall be sent in
                  writing in English by registered airmail, internationally
                  recognized courier or telefaxed to the following addresses:


                                       28
<PAGE>

                  If to Newco at:

                  Acusphere Newco, Ltd.,
                  c/o Acusphere, Inc
                  500 Arsenal Street
                  Watertown, MA 02472
                  Attn: Chief Executive Officer

                  Telephone         617-648-8800
                  Fax:              617-926-4750
                  Appleby Spurling & Kempe
                  Cedar House
                  41 Cedar Avenue
                  Hamilton
                  HM 12
                  Bermuda

                  Attention: Judith Collis

                  Telephone:        441-298-3211
                  Fax:              441-298-3475

                  with a copy to JVP at:

                  Acusphere, Inc
                  500 Arsenal Street
                  Watertown, MA 02472
                  Attn: Chief Executive Officer

                  Telephone         617-648-8800
                  Fax:              617-926-4750

                  If to JVP at:

                  Acusphere, Inc
                  500 Arsenal Street
                  Watertown, MA 02472
                  Attn: Chief Executive Officer

                  Telephone         617-648-8800
                  Fax:              617-926-4750

                  with a copy to:
                  Lawrence S. Wittenberg
                  Testa, Hurwitz & Thibeault, LLP


                                       29
<PAGE>

                  123 High Street
                  Boston, Massachusetts 02110

                  Telephone:        617-248-7000
                  Fax:              617-248-7100

                  If to Elan, EIS, and/or EPIL Shannon at:

                  Elan Corporation, plc
                  Elan Pharma International Limited
                  Elan International Services, Ltd.
                  C/o Elan International Services, Ltd.
                  102 St. James Court
                  Flatts,
                  Smiths FL04
                  Bermuda
                  Attention:        Secretary
                  Telephone:        441 292 9169
                  Fax:              441 292 2224

                  or to such other address(es) and telefax numbers as may from
                  time to time be notified by any Party to the others hereunder.

         10.3.2   Any notice sent by mail shall be deemed to have been delivered
                  within seven (7) working days after dispatch or delivery to
                  the relevant courier and notice sent by fax shall be deemed to
                  have been delivered upon confirmation receipt. Notice of
                  change of address shall be effective upon receipt.

10.4     WAIVER

         No waiver of any right under this Agreement shall be deemed effective
         unless contained in a written document signed by the Party charged with
         such waiver, and no waiver of any breach or failure to perform shall be
         deemed to be a waiver of any future breach or failure to perform or of
         any other right arising under this Agreement.

10.5     SEVERABILITY

         If any provision in this Agreement is agreed by the Parties to be, or
         is deemed to be, or becomes invalid, illegal, void or unenforceable
         under any law that is applicable hereto:

         10.5.1   such provision will be deemed amended to conform to applicable
                  laws so as to be valid and enforceable; or


                                       30
<PAGE>

         10.5.2   if it cannot be so amended without materially altering the
                  intention of the Parties, it will be deleted, with effect from
                  the date of this Agreement or such earlier date as the Parties
                  may agree, and the validity, legality and enforceability of
                  the remaining provisions of this Agreement shall not be
                  impaired or affected in any way.

10.6     FURTHER ASSURANCES

         At the request of any of the Parties, the other Party or Parties shall
         (and shall use reasonable efforts to procure that any other necessary
         parties shall) execute and perform all such documents, acts and things
         as may reasonably be required subsequent to the signing of this
         Agreement for assuring to or vesting in the requesting Party the full
         benefit of the terms hereof.

10.7     SUCCESSORS

         This Agreement shall be binding upon and inure to the benefit of the
         Parties hereto and their respective successors and permitted assigns.

10.8     AMENDMENTS

         No amendment, modification or addition hereto shall be effective or
         binding on any Party unless set forth in writing and executed by a duly
         authorized representative of each Party.

10.9     COUNTERPARTS

         This Agreement may be executed in any number of counterparts, each of
         which when so executed shall be deemed to be an original and all of
         which when taken together shall constitute this Agreement.

10.10    COSTS

         Each Party shall bear its own costs and expenses in connection with the
         transactions contemplated by this Agreement.

10.11    FORCE MAJEURE:

         Neither Party to this Agreement shall be liable for failure or delay in
         the performance of any of its obligations hereunder if such failure or
         delay results from Force Majeure, but any such failure or delay shall
         be remedied by such Party as soon as practicable.


                                       31
<PAGE>

10.12    RELATIONSHIP OF THE PARTIES:

         The Parties are independent contractors under this Agreement. Nothing
         herein contained shall be deemed to create or establish an employment,
         agency, joint venture, or partnership relationship between the Parties
         or any of their agents or employees, or any other legal arrangement
         that would impose liability upon one Party for the act or failure to
         act of any other Party.

         No Party shall have any express or implied power to enter into any
         contracts, commitments or negotiations or to incur any liabilities in
         the name of, or on behalf of, any other Party, or to bind any other
         Party in any respect whatsoever.

10.13    ENTIRE AGREEMENT:

         10.13.1           This Agreement sets forth all of the agreements and
                           understandings between the Parties with respect to
                           the subject matter hereof. There are no agreements or
                           understandings with respect to the subject matter
                           hereof, either oral or written, between the Parties
                           other than as set forth in this Agreement.

         10.13.2           No provision of this Agreement shall be construed so
                           as to negate, modify or affect in any way the
                           provisions of any other agreement between the Parties
                           unless specifically provided herein and only to the
                           extent so specified.

10.14    TAX RETURNS:

         JVP shall prepare and file all future tax returns for Newco, making any
         elections it deems necessary or appropriate.





                                       32
<PAGE>




                                  SCHEDULE 2.3

            Codan Services Invoice 4156759 in the amount of $4745.20




                                       33
<PAGE>





                                  SCHEDULE 3.4

                                  BALANCE SHEET



                                       34
<PAGE>





                                  SCHEDULE 4.1

                 JVP IMPROVEMENTS / NEWCO INTELLECTUAL PROPERTY

o        [CONFIDENTIAL TREATMENT REQUESTED] /*/

o        [CONFIDENTIAL TREATMENT REQUESTED] /*/

o        [CONFIDENTIAL TREATMENT REQUESTED] /*/

o        [CONFIDENTIAL TREATMENT REQUESTED] /*/





                                       35
<PAGE>





                                   SCHEDULE 5

        ACUSPHERE [CONFIDENTIAL TREATMENT REQUESTED] /*/ PRODUCT PATENTS

[CONFIDENTIAL TREATMENT REQUESTED] /*/

[CONFIDENTIAL TREATMENT REQUESTED] /*/

[CONFIDENTIAL TREATMENT REQUESTED] /*/





                                       36
<PAGE>





IN WITNESS WHEREOF the Parties have executed this Agreement.


SIGNED


BY:   /s/ Debbie Buryj
      ------------------------------------
for and on behalf of
ELAN CORPORATION, PLC


SIGNED


BY:   /s/ Debbie Buryj
      ------------------------------------
for and on behalf of
ELAN PHARMA INTERNATIONAL LIMITED


SIGNED


BY:   /s/ illegible signature
      ------------------------------------
for and on behalf of
ELAN INTERNATIONAL SERVICES, LTD.



SIGNED


BY:   /s/ Sherri C. Oberg
      ------------------------------------
for and on behalf of
ACUSPHERE NEWCO, LTD.



SIGNED


BY:   /s/ Sherri C. Oberg
      ------------------------------------
for and on behalf of
ACUSPHERE, INC.



                                       37