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                                                                    Exhibit 10.1

                          SECURITIES PURCHASE AGREEMENT

      This SECURITIES PURCHASE AGREEMENT (this "Agreement"), dated as of May 7,
2004 is made by and among Sonus Pharmaceuticals, Inc., a Delaware corporation,
with headquarters located at 22026 20th Avenue S.E., Bothell, Washington 98021
(the "Company"), and the investors named on the signature pages hereto, together
with their permitted transferees (each, an "Investor" and collectively, the
"Investors").

                                    RECITALS:

      A.    The Company and the Investors are executing and delivering this
Agreement in reliance upon the exemption from securities registration afforded
by Section 4(2) of the Securities Act and Rule 506 under Regulation D.

      B.    The Investors desire, upon the terms and conditions stated in this
Agreement, to purchase up to 2,900,000 shares of the Company's Common Stock (the
"Common Shares"). The purchase price per share of the Common Shares is $5.25
("Purchase Price").

      C.    Contemporaneously with the execution and delivery of this Agreement,
the parties hereto are executing and delivering a Registration Rights Agreement
under which the Company has agreed to provide certain registration rights under
the Securities Act, the rules and regulations promulgated thereunder and
applicable state securities laws.

      D.    The capitalized terms used herein and not otherwise defined have the
meanings given them in Article IX hereof.

      In consideration of the premises and the mutual covenants contained herein
and other good and valuable consideration, the receipt and sufficiency of which
are hereby acknowledged, the Company and the Investors hereby agree as follows:

                                   ARTICLE I
                         PURCHASE AND SALE OF SECURITIES

      1.1   Purchase and Sale of Common Shares. At the Closing, subject to the
terms of this Agreement and the satisfaction or waiver of the conditions set
forth in Articles VI and VII hereof, the Company will issue and sell to each
Investor, and each Investor will (on a several and not a joint basis) purchase
from the Company, the number of Common Shares set forth beneath such Investor's
name on the signature pages hereof.

      1.2   Payment. At or prior to the Closing, each Investor will pay the
purchase price for the number of Common Shares set forth beneath its name on the
signature pages hereof, by wire transfer of immediately available funds in
accordance with the wire instructions set forth on Exhibit A hereto. The Company
shall deliver to each Investor certificates representing the Common Shares so
purchased by such Investor within two (2) business days following the Closing
Date against delivery of the Purchase Price as described above.

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      1.3   Closing Date. Subject to the satisfaction or waiver of the
conditions set forth in Articles VI and VII hereof, the Closing will take place
at 8 a.m. Pacific Standard Time on May 7, 2004 or at such other date or time
agreed upon by the parties to this Agreement (the "Closing Date"). The Closing
will be held at the offices of Stradling Yocca Carlson & Rauth or at such other
place as the parties agree.

                                   ARTICLE II
                    INVESTOR'S REPRESENTATIONS AND WARRANTIES

      Each Investor represents and warrants to the Company, severally and solely
with respect to itself and its purchase hereunder and not with respect to any
other Investor, that:

      2.1   Investment Purpose. The Investor is purchasing the Common Shares for
its own account and not with a present view toward the public sale or
distribution thereof, except pursuant to sales registered or exempted from
registration under the Securities Act ; provided, however, that by making the
representation herein, the Investor does not agree to hold any of the Common
Shares for any minimum or other specific term and reserves the right to dispose
of the Common Shares at any time in accordance with or pursuant to a
registration statement or an exemption from registration under the Securities
Act.

      2.2   Accredited Investor Status. The Investor is an "accredited investor"
as defined in Rule 501(a) of Regulation D. The Investor has delivered an
Investor Questionnaire in the form of Exhibit B to the Company and to Granite
Financial Group, Inc.

      2.3   Reliance on Exemptions. The Investor understands that the Common
Shares are being offered and sold to it in reliance upon specific exemptions
from the registration requirements of United States federal and state securities
laws and that the Company is relying upon the truth and accuracy of, and the
Investor's compliance with, the representations, warranties, agreements,
acknowledgments and understandings of the Investor set forth herein in order to
determine the availability of such exemptions and the eligibility of the
Investor to acquire the Common Shares.

      2.4   Information. The Investor has received and read the SEC Documents.
The Investor and its advisors, if any, have been furnished with all materials
relating to the business, finances and operations of the Company, and materials
relating to the offer and sale of the Common Shares, that have been requested by
the Investor or its advisors, if any. The Investor and its advisors, if any,
have been afforded the opportunity to ask questions of the Company. Neither such
inquiries nor any other due diligence investigation conducted by Investor or any
of its advisors or representatives modify, amend or affect the Investor's right
to rely on the Company's representations and warranties contained in Article III
below. The Investor acknowledges and understands that its investment in the
Common Shares involves a significant degree of risk.

      2.5   Governmental Review. The Investor understands that no United States
federal or state agency or any other government or governmental agency has
passed upon or made any recommendation or endorsement of the Common Shares or an
investment therein.

      2.6   Transfer or Resale. The Investor understands that:

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            (a)   except as provided in the Registration Rights Agreement, the
Common Shares have not been and are not being registered under the Securities
Act or any applicable state securities laws and, consequently, the Investor may
have to bear the risk of owning the Common Shares for an indefinite period of
time because the Common Shares may not be transferred unless (i) the resale of
the Common Shares is registered pursuant to an effective registration statement
under the Securities Act ; (ii) the Investor has delivered to the Company an
opinion of counsel (in form, substance and scope customary for opinions of
counsel in comparable transactions) to the effect that the Common Shares to be
sold or transferred may be sold or transferred pursuant to an exemption from
such registration; (iii) the Common Shares are sold or transferred pursuant to
Rule 144; or (iv) the Common Shares are sold or transferred to an affiliate (as
defined in Rule 144) of the Investor;

            (b)   any sale of the Common Shares made in reliance on Rule 144 may
be made only in accordance with the terms of Rule 144 and, if Rule 144 is not
applicable, any resale of the Common Shares under circumstances in which the
seller (or the person through whom the sale is made) may be deemed to be an
underwriter (as that term is defined in the Securities Act ) may require
compliance with some other exemption under the Securities Act or the rules and
regulations of the SEC thereunder; and

            (c)   except as set forth in the Registration Rights Agreement,
neither the Company nor any other person is under any obligation to register the
Common Shares under the Securities Act or any state securities laws or to comply
with the terms and conditions of any exemption thereunder.

      2.7   Legends. The Investor understands that until (a) the Common Shares
may be sold by the Investor under Rule 144(k) or (b) such time as the resale of
the Common Shares has been registered under the Securities Act as contemplated
by the Registration Rights Agreement, the certificates representing the Common
Shares will bear a restrictive legend in substantially the following form (and a
stop-transfer order may be placed against transfer of the certificates for such
Common Shares):

      THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED
      UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR THE SECURITIES LAWS OF
      ANY STATE OF THE UNITED STATES. THE SECURITIES MAY NOT BE SOLD,
      TRANSFERRED OR ASSIGNED IN THE ABSENCE OF AN EFFECTIVE REGISTRATION
      STATEMENT FOR THE SECURITIES UNDER APPLICABLE SECURITIES LAWS, OR UNLESS
      OFFERED, SOLD OR TRANSFERRED PURSUANT TO AN AVAILABLE EXEMPTION FROM THE
      REGISTRATION REQUIREMENTS OF THOSE LAWS.

      The legend set forth above will be removed and the Company will issue a
certificate without the legend to the holder of any certificate upon which it is
stamped, in accordance with the terms of Article V hereof.

      2.8   Authorization; Enforcement. This Agreement and the Registration
Rights Agreement have been duly and validly authorized, executed and delivered
on behalf of the Investor and are valid and binding agreements of the Investor
enforceable in accordance with their terms, subject to the effect of any
applicable bankruptcy, insolvency, reorganization, moratorium or similar laws
affecting the rights of creditors generally and the application of general
principles of equity.

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      2.9   Residency. The Investor is a resident of (or, if an entity, has its
principal place of business in) the jurisdiction set forth immediately below
such Investor's name on the signature pages hereto.

      2.10  Independent Investment. No Investor has agreed to act with any other
Investor for the purpose of acquiring, holding, voting or disposing of the
Common Shares purchased hereunder for purposes of Section 13(d) under the
Exchange Act, and each Investor is acting independently with respect to its
investment in the Common Shares. The Company acknowledges that it has elected to
provide all Investors with the same terms and transaction documents for the
convenience of the Company and not because it was required or requested to do so
by the Investors.

      2.11  Acknowledgements Regarding Placement Agent. The Investor
acknowledges that Granite Financial Group, Inc. is acting as placement agent
(the "Placement Agent") for the Common Shares being offered hereby and will be
compensated by the Company for acting in such capacity. The Investor further
acknowledges that the Placement Agent has acted solely as placement agent in
connection with the offering of the Common Shares by the Company, that the
information and data provided to the Investor in connection with the
transactions contemplated hereby have not been subjected to independent
verification by the Placement Agent, and that the Placement Agent makes no
representation or warranty with respect to the accuracy or completeness of such
information, data or other related disclosure material. The Investor further
acknowledges that in making its decision to enter into this Agreement and
purchase the Common Shares it has relied on its own examination of the Company
and the terms of, and consequences, of holding the Common Shares. The Investor
further acknowledges that the provisions of this Section 2.11 are for the
benefit of, and may be enforced by, the Placement Agent.

                                  ARTICLE III
                  REPRESENTATIONS AND WARRANTIES OF THE COMPANY

      The Company represents and warrants to the Investors that:

      3.1   Organization and Qualification. The Company is duly incorporated,
validly existing and in good standing under the laws of the jurisdiction in
which it is incorporated, with full power and authority (corporate and other) to
own, lease, use and operate its properties and to carry on its business as and
where now owned, leased, used, operated and conducted. The Company is duly
qualified to do business and is in good standing in every jurisdiction in which
the nature of the business conducted by it makes such qualification necessary,
except where the failure to be so qualified or in good standing would not have a
Material Adverse Effect.

      3.2   Authorization; Enforcement. (a) The Company has all requisite
corporate power and authority to enter into and to perform its obligations under
this Agreement and the Registration Rights Agreement, to consummate the
transactions contemplated hereby and thereby and to issue the Common Shares in
accordance with the terms hereof and thereof; (b) the execution, delivery and
performance of this Agreement and the Registration Rights Agreement by the
Company and the consummation by it of the transactions contemplated hereby and
thereby (including, without limitation, the issuance of the Common Shares) have
been duly authorized by the Company's Board of Directors and no further consent
or authorization of the Company, its Board or Directors, or its shareholders is
required; (c) this Agreement and the Registration Rights Agreement have been
duly executed by the Company; and (d) each of this Agreement and the
Registration Rights Agreement

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constitutes a legal, valid and binding obligation of the Company enforceable
against the Company in accordance with its terms, subject to the effect of any
applicable bankruptcy, insolvency, reorganization, or moratorium or similar laws
affecting the rights of creditors generally and the application of general
principles of equity.

      3.3   Capitalization. As of the date hereof, the authorized capital stock
of the Company consists of (a) 75,000,000 shares of Common Stock, par value
$.001 per share, of which 18,324,997 shares are issued and outstanding,
2,632,697 shares are reserved for issuance upon exercise of stock options
outstanding under the Company's employee and director stock option plans,
1,021,879 shares are reserved for grants of rights to purchase under the
Company's employee and director stock option plans, 70,647 shares are reserved
for issuance pursuant to the Company's employee stock purchase plan and 401(k)
plan and 1,828,116 shares are reserved for issuance under warrants issued by the
Company on June 15, 2001, January 18, 2002 and July 28, 2003; (b) 5,000,000
shares of preferred stock, par value $.001 per share, 500,000 of which shares
are designated Series A Junior Participating Preferred Stock, par value $.001
per share, none of which is issued and outstanding. All of such outstanding
shares of capital stock are, or upon issuance will be, duly authorized, validly
issued, fully paid and nonassessable. No shares of capital stock of the Company,
including the Common Shares issuable pursuant to this Agreement, are subject to
preemptive rights or any other similar rights of the stockholders of the Company
or any liens or encumbrances imposed through the actions or failure to act of
the Company. Except as disclosed in this Section 3.3 and except for the
transactions contemplated hereby, (i) there are no outstanding options,
warrants, scrip, rights to subscribe for, puts, calls, rights of first refusal
or preemptive or other similar rights, agreements, understandings, claims or
other commitments or rights of any character whatsoever relating to, or
securities or rights directly or indirectly convertible into, exercisable for,
or exchangeable for any shares of capital stock of the Company, or arrangements
by which the Company is or may become bound to issue additional shares of
capital stock of the Company; (ii) there are no agreements or arrangements
(other than the Registration Rights Agreement, the separate Registration Rights
Agreements entered into on June 15, 2001, January 18, 2002, and July 28, 2003
and the Purchase Warrants dated June 15, 2001) under which the Company is
obligated to register the sale of any of its securities under the Securities Act
and (iii) there are no anti-dilution or price adjustment provisions contained in
any security issued by the Company (or in any agreement providing rights to
security holders) that will be triggered by the issuance of the Common Shares
(other than the exercise price adjustments pursuant to the warrants to purchase
an aggregate of 385,800 shares of Common Stock, issued by the Company on January
18, 2002). The Company has furnished to the Investors true and correct copies of
the Company's Certificate of Incorporation, as amended, as in effect on the date
hereof, the Company's Bylaws as in effect on the date hereof and the terms of
all securities convertible into or exercisable for Common Stock of the Company
and the material rights of the holders thereof in respect thereto.

      3.4   Issuance of Common Shares. The Common Shares are duly authorized
and, upon issuance in accordance with the terms of this Agreement, will be
validly issued, fully paid and non-assessable, free from all taxes, liens,
claims, encumbrances and charges with respect to the issue thereof, will not be
subject to preemptive rights or other similar rights of stockholders of the
Company, and will not impose personal liability on the holders thereof.

      3.5   No Conflicts; No Violation.

            (a)   The execution, delivery and performance of this Agreement and
the Registration Rights Agreement by the Company and the consummation by the
Company of the

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transactions contemplated hereby and thereby (including, without limitation, the
issuance of the Common Shares) will not (i) conflict with or result in a
violation of any provision of its Certificate of Incorporation or Bylaws or (ii)
violate or conflict with, or result in a breach of any provision of, or
constitute a default (or an event which with notice or lapse of time or both
could become a default) under, or give to others any rights of termination,
amendment (including without limitation, the triggering of any anti-dilution
provision), acceleration or cancellation of, any agreement, indenture, patent,
patent license, or instrument to which the Company is a party, or (iii) result
in a violation of any law, rule, regulation, order, judgment or decree
(including U.S. federal and state securities laws and regulations and
regulations of any self-regulatory organizations to which the Company or its
securities are subject) applicable to the Company or by which any property or
asset of the Company is bound or affected (except for such conflicts, breaches,
defaults, terminations, amendments, accelerations, cancellations and violations
as would not, individually or in the aggregate, have a Material Adverse Effect).

            (b)   The Company is not in violation of its Certificate of
Incorporation, Bylaws or other organizational documents and the Company is not
in default (and no event has occurred which with notice or lapse of time or both
could put the Company in default) under any agreement, indenture or instrument
to which the Company is a party or by which any property or assets of the
Company is bound or affected, except for possible defaults as would not,
individually or in the aggregate, have a Material Adverse Effect.

            (c)   The Company is not conducting its business in violation of any
law, ordinance or regulation of any governmental entity, the failure to comply
with which would, individually or in the aggregate, have a Material Adverse
Effect.

            (d)   Except as specifically contemplated by this Agreement and as
required under the Securities Act and any applicable state securities laws or
any listing agreement with any securities exchange or automated quotation
system, the Company is not required to obtain any consent, authorization or
order of, or make any filing or registration with, any court or governmental
agency or any regulatory or self regulatory agency in order for it to execute,
deliver or perform any of its obligations under this Agreement and the
Registration Rights Agreement, in each case in accordance with the terms hereof
or thereof, or to issue and sell the Common Shares in accordance with the terms
hereof. All consents, authorizations, orders, filings and registrations which
the Company is required to obtain pursuant to the preceding sentence have been
obtained or effected on or prior to the date hereof. The Company is not in
violation of the listing requirements of Nasdaq.

      3.6   SEC Documents, Financial Statements. Since June 30, 2001, the
Company has timely filed all reports, schedules, forms, statements and other
documents required to be filed by it with the SEC pursuant to the reporting
requirements of the Exchange Act (all of the foregoing filed prior to the date
hereof and all exhibits included therein and financial statements and schedules
thereto and documents (other than exhibits) incorporated by reference therein,
being hereinafter referred to herein as the "SEC Documents"). The Company has
delivered to each Investor, or each Investor has had access to, true and
complete copies of the SEC Documents, except for such exhibits and incorporated
documents. As of their respective dates, the SEC Documents complied in all
material respects with the requirements of the Exchange Act or the Securities
Act , as the case may be, and the rules and regulations of the SEC promulgated
thereunder applicable to the SEC Documents, and none of the SEC Documents, at
the time they were filed with the SEC, contained any untrue statement of a
material fact or omitted to state a material fact required to be stated therein
or necessary in order to make the statements therein, in light of the
circumstances under which they

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were made, not misleading. As of their respective dates, the financial
statements of the Company included in the SEC Documents complied in all material
respects with applicable accounting requirements and the published rules and
regulations of the SEC with respect thereto. Such financial statements have been
prepared in accordance with U.S. generally accepted accounting principles,
consistently applied, during the periods involved (except (i) as may be
otherwise indicated in such financial statements or the notes thereto, or (ii)
in the case of unaudited interim statements, to the extent they may not include
footnotes or may be condensed or summary statements) and fairly present in all
material respects the financial position of the Company as of the dates thereof
and the results of its operations and cash flows for the periods then ended
(subject, in the case of unaudited statements, to normal year-end audit
adjustments). Except as set forth in the financial statements included in the
SEC Documents, the Company has no liabilities, contingent or otherwise, other
than liabilities incurred in the ordinary course of business subsequent to
December 31, 2003, and liabilities of the type not required under generally
accepted accounting principles to be reflected in such financial statements.
Such liabilities incurred subsequent to December 31, 2003, are not, in the
aggregate, material to the financial condition or operating results of the
Company.

      3.7   Absence of Certain Changes. Except as disclosed in the SEC
Documents, since December 31, 2003, there has been no material adverse change in
the assets, liabilities, business, properties, operations, financial condition,
prospects or results of operations of the Company, and the Company has not (i)
varied its business plan or practices, in any material respect, from past
practices, (ii) entered into any material financing, joint venture, license or
similar arrangements or (iii) suffered or permitted to be incurred any liability
or obligation against any of its properties or assets that would limit or
restrict its ability to perform its obligations hereunder.

      3.8   Absence of Litigation. Except as disclosed in the SEC Documents,
there is no action, suit, claim, proceeding, inquiry or investigation before or
by any court, public board, government agency, self-regulatory organization or
body pending or, to the knowledge of the Company, threatened against or
affecting the Company or any of its officers or directors acting as such that
could, individually or in the aggregate, have a Material Adverse Effect.

      3.9   Intellectual Property Rights. The Company owns or possesses the
licenses or rights to use all patents, patent applications, patent rights,
inventions, know-how, trade secrets, trademarks, trademark applications, service
marks, service names, trade names and copyrights necessary to enable it to
conduct its business as now operated or as currently proposed to be operated
(the "Intellectual Property"). Except as set forth in the SEC Documents, there
are no material outstanding options, licenses or agreements relating to the
Intellectual Property, nor is the Company bound by or a party to any material
options, licenses or agreements relating to the patents, patent applications,
patent rights, inventions, know-how, trade secrets, trademarks, trademark
applications, service marks, service names, trade names or copyrights of any
other person or entity. Except as disclosed in the SEC Documents, there is no
claim or action or proceeding pending or, to the Company's knowledge, threatened
that challenges the right of the Company with respect to any Intellectual
Property. Except as set forth in the SEC Documents, to the knowledge of the
Company, the Company's Intellectual Property does not infringe any intellectual
property rights of any other person which, if the subject of an unfavorable
decision, ruling or finding would have a Material Adverse Effect.

      3.10  Tax Status. The Company has timely made or filed all federal, state
and foreign income and all other tax returns, reports and declarations required
by any jurisdiction to which it is subject (unless and only to the extent that
the Company has set aside on its books provisions

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reasonably adequate for the payment of all unpaid and unreported taxes) and has
timely paid all taxes and other governmental assessments and charges, shown or
determined to be due on such returns, reports and declarations, except those
being contested in good faith, and has set aside on its books provisions
reasonably adequate for the payment of all taxes for periods subsequent to the
periods to which such returns, reports or declarations apply. To the knowledge
of the Company, there are no unpaid taxes claimed to be due by the taxing
authority of any jurisdiction, and the officers of the Company know of no basis
for any such claim. The Company has not executed a waiver with respect to the
statute of limitations relating to the assessment or collection of any foreign,
federal, state or local tax. None of the Company's tax returns is presently
being audited by any taxing authority.

      3.11  Environmental Laws. The Company (i) is in compliance with all
applicable foreign federal, state and local laws and regulations relating to the
protection of human health and safety, the environment or hazardous or toxic
substances or wastes, pollutants or contaminants ("Environmental Laws"), (ii)
has received all permits, licenses or other approvals required of them under
applicable Environmental Laws to conduct its business and (iii) is in compliance
with all terms and conditions of any such permit, license or approval where, in
each of the three foregoing clauses, the failure to so comply would have,
individually or in the aggregate, a Material Adverse Effect.

      3.12  No Integrated Offering. Neither the Company, nor any of its
affiliates, nor any person acting on its or their behalf, has directly or
indirectly made any offers or sales in any security or solicited any offers to
buy any security under circumstances that would require registration under the
Securities Act of the issuance of the Common Shares to the Investors. The
issuance of the Common Shares to the Investors will not be integrated with any
other issuance of the Company's securities (past, current or future) for
purposes of the Securities Act or any applicable rules of Nasdaq.

      3.13  No Brokers. The Company has taken no action which would give rise to
any claim by any person for brokerage commissions, finder's fees or similar
payments relating to this Agreement or the transactions contemplated hereby,
except for dealings with Granite Financial Group, Inc., whose commissions and
fees will be paid for by the Company.

      3.14  Insurance. The Company is insured by insurers of recognized
financial responsibility against such losses and risks and in such amounts as
management of the Company believes to be prudent and customary in the businesses
in which the Company is engaged.

      3.15  Employment Matters. The Company is in compliance with all federal,
state, local and foreign laws and regulations respecting employment and
employment practices, terms and conditions of employment and wages and hours,
except where failure to be in compliance would not have a Material Adverse
Effect. The Company is not bound by or subject to (and none of its assets or
properties is bound by or subject to) any written or oral, express or implied,
contract, commitment or arrangement with any labor union, and no labor union has
requested or, to the Company's knowledge, has sought to represent any of the
employees, representatives or agents of the Company. There is no strike or other
labor dispute involving the Company pending, or to the Company's knowledge,
threatened nor is the Company aware of any labor organization activity involving
its employees. The Company is not aware that any officer or key employee, or
that any group of officers or key employees, intends to terminate their
employment with the Company, nor does the Company have a present intention to
terminate the employment of any of the foregoing.

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      3.16  Employee Benefit Plans. Except as set forth in the Offering
Memorandum, the Company does not have any Employee Benefit Plans, as such term
is defined in the Employee Retirement Security Act of 1974.

      3.17  Investment Company Status. The Company is not and upon consummation
of the sale of the Common Shares will not be an "investment company," a company
controlled by an "investment company" or an "affiliated person" of, or
"promoter" or "principal underwriter" for, an "investment company" as such terms
are defined in the Investment Company Act of 1940, as amended.

      3.18  No Subsidiaries. The Company does not presently own or control,
directly or indirectly, any interest in any other corporation, association,
joint venture, partnership or other business entity and the Company is not a
direct or indirect participant in any joint venture or partnership.

      3.19  No Conflict of Interest. The Company is not indebted, directly or
indirectly, to any of its officers or directors or to their respective spouses
or children, in any amount whatsoever other than in connection with expenses or
advances of expenses incurred in the ordinary course of business or relocation
expenses of employees. None of the Company's officers, directors or employees,
or any members of their immediate families, are directly, or indirectly,
indebted to the Company or, to the best of the Company's knowledge, have any
direct or indirect ownership interest in any entity with which the Company is
affiliated or with which the Company has a business relationship, or any entity
which competes with the Company, except that officers, directors, employees
and/or stockholders of the Company may own stock in (but not exceeding five
percent (5%) of the outstanding capital stock of) any publicly traded company
that may compete with the Company. To the best of the Company's knowledge, none
of the Company's officers, directors or employees or any members of their
immediate families are, directly or indirectly, interested in any material
contract with the Company. The Company is not a guarantor or indemnitor of any
indebtedness of any other person or entity.

      3.20  Nasdaq Notification. The Company has notified Nasdaq of the issuance
and listing of the Common Shares on Nasdaq and the Common Shares have been
approved for quotation on Nasdaq, upon official notice of issuance.

      3.21  Reporting Status; Eligibility to Use Form S-3. The Company's Common
Stock is registered under Section 12g of the Exchange Act. The Company currently
meets the "registrant eligibility" requirements set forth in the general
instructions to Form S-3 to enable the registration of the Registrable Common
Shares, as defined in the Registration Rights Agreement.

      3.22  No Manipulation of Stock. The Company has not taken and will not, in
violation of applicable law, take, any action designed to or that might
reasonably be expected to cause or result in stabilization or manipulation of
the price of the Common Stock to facilitate the sale or resale of the Common
Shares.

      3.23  Delisting Notification. The Company has not received notice (written
or oral) from the Nasdaq to the effect that the Company is not in compliance
with the listing or maintenance requirements of such market.

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      3.24  Sarbanes-Oxley Act. The Company is in substantial compliance with
the applicable provisions of the Sarbanes-Oxley Act of 2002 (the "Sarbanes-Oxley
Act"), and the rules and regulations promulgated thereunder, that are effective
and for which compliance by the Company is required as of the date hereof and
intends to comply substantially with other applicable provisions of the
Sarbanes-Oxley Act, and the rules and regulations promulgated thereunder, upon
the effectiveness of such provisions or the date by which compliance therewith
by the Company is required.

      3.25  Representations Complete. The representations and warranties made by
the Company in this Agreement, the statements made in any certificates furnished
by the Company pursuant to this Agreement, and the statements made by the
Company in any documents mailed, delivered or furnished to the Investors in
connection with this Agreement, taken as a whole, do not contain and will not
contain, as of their respective dates and as of the Closing Date, any untrue
statement of a material fact, nor do they omit or will they omit, as of their
respective dates or as of the Closing Date, to state any material fact necessary
in order to make the statements contained herein or therein, in the light of the
circumstances under which they were made, not misleading.

                                   ARTICLE IV
                                    COVENANTS

      4.1   Best Efforts. Each party will use its best efforts to satisfy in a
timely fashion each of the conditions to be satisfied by it under Articles VI
and VII of this Agreement.

      4.2   Form D; Blue Sky Laws. The Company will timely file a Notice of Sale
of Common Shares on Form D with respect to the Common Shares, as required under
Regulation D. The Company will, on or before the Closing Date, take such action
as it reasonably determines to be necessary to qualify the Common Shares for
sale to the Investors under this Agreement under applicable securities (or "blue
sky") laws of the states of the United States (or to obtain an exemption from
such qualification).

      4.3   Continued Eligibility to Use Form S-3. Throughout the Registration
Period (as defined in the Registration Rights Agreement), the Company will
timely file all reports, schedules, forms, statements and other documents
required to be filed by it with the SEC under the reporting requirements of the
Exchange Act, and the Company will not terminate its status as an issuer
required to file reports under the Exchange Act even if the Exchange Act or the
rules and regulations thereunder would permit such termination. The Company will
take all reasonably necessary action to continue to meet, the "registrant
eligibility" requirements set forth in the general instructions to Form S-3 to
enable the registration of the Registrable Common Shares as defined in the
Registration Rights Agreement.

      4.4   Expenses. The Company and each Investor is liable for, and will pay,
its own expenses incurred in connection with the negotiation, preparation,
execution and delivery of this Agreement and the other agreements to be executed
in connection herewith, including, without limitation, attorneys' and
consultants' fees and expenses; provided, that if the transactions contemplated
hereby are consummated, the Company will pay the fees and expenses of one
special counsel to the Investors, not to exceed $15,000.

                                       10

<PAGE>

      4.5   Financial Information. As long as an Investor owns any of the Common
Shares, the financial statements of the Company will be prepared in accordance
with United States generally accepted accounting principles, consistently
applied, and will fairly present in all material respects the consolidated
financial position of the Company and results of its operations and cash flows
as of, and for the periods covered by, such financial statements (subject, in
the case of unaudited statements, to normal year-end audit adjustments).

      4.6   Compliance with Law. As long as an Investor owns any of the Common
Shares, the Company will conduct its business in compliance with all applicable
laws, rules and regulations of the jurisdictions in which it is conducting
business, including, without limitation, all applicable local, state and federal
environmental laws and regulations, the failure to comply, individually or in
the aggregate, with which would have a Material Adverse Effect.

      4.7   No Integration. The Company will not make any offers or sales of any
security or solicit offers to buy or otherwise negotiate in respect of any offer
or sale of any security (other than the Common Shares) under circumstances that
would cause the offering of the Common Shares to be integrated with any other
offering of securities by the Company (i) for the purpose of any stockholder
approval provision applicable to the Company or its securities or (ii) for
purposes of any registration requirement under the Securities Act .

      4.8   Sales by Investors. Each Investor will sell any Common Shares sold
by it in compliance with applicable prospectus delivery requirements, if any, or
otherwise in compliance with the requirements for an exemption from registration
under the Securities Act and the rules and regulations promulgated thereunder.
No Investor will make any sale, transfer or other disposition of the Common
Shares in violation of federal or state securities laws.

      4.9   Disclosure of Material Information. The Company covenants and agrees
that neither it nor, to its knowledge, any other person acting on its behalf has
provided or will provide any Investor or its agents or counsel with any
information that the Company believes constitutes material non-public
information, unless prior thereto such Investor shall have executed a written
agreement regarding the confidentiality and use of such information. The Company
understands and confirms that each Investor shall be relying on the foregoing in
effecting transactions in Common Shares of the Company.

      4.10  Other Financing. The Company will not issue any shares of Common
Stock or warrants, options or other rights to purchase Common Stock at a price
per share, including the exercise price payable upon the exercise of any
warrant, option or other right to purchase, below the Purchase Price for the
sole purpose of raising capital prior to the date on which the registration
statement to be filed pursuant to Section 2.1 of the Registration Rights
Agreement is declared effective by the SEC. This restriction shall not apply to
(i) Common Stock or options to acquire Common Stock issued to employees,
officers or directors of the Company pursuant to a stock option or equity
incentive plan, including, without limitation, the Company's employee stock
purchase plan and 401(k) profit sharing plan, duly adopted by the Board of
Directors of the Company, (ii) securities issued upon the conversion of any
convertible securities or exercise of any warrants, options or other rights to
purchase Common Stock outstanding as of the date hereof, (iii) the issuance of
securities in connection with mergers, acquisitions, strategic business
partnerships or joint ventures, the primary purpose of which, in the reasonable
judgment of the Board of Directors of the Company, is not to raise additional
capital, (iv) the issuance of securities pursuant to any equipment financing
from a bank or similar financial or lending institution approved by the Board of
Directors of the Company,

                                       11

<PAGE>

or (v) any issuance of securities as to which the holders of a majority of the
Common Shares issued to the Investors under this Agreement shall have consented
to in writing.

                                   ARTICLE V
                 TRANSFER AGENT INSTRUCTIONS; REMOVAL OF LEGENDS

      5.1   Issuance of Certificates. The Company will, or will instruct its
transfer agent to, issue certificates, registered in the name of each Investor
or its nominee, for the Common Shares. All such certificates will bear the
restrictive legend described in Section 2.7, except as otherwise specified in
this Article V. The Company will not give to its transfer agent any instruction
other than as described in this Article V and stop transfer instructions to give
effect to Section 2.7 hereof (prior to registration of the Common Shares under
the Securities Act ). Nothing in this Section will affect in any way the
Investor's obligations to comply with all applicable prospectus delivery
requirements, if any, upon resale of the Common Shares.

      5.2   Unrestricted Common Shares. If, unless otherwise required by
applicable state securities laws, (a) the Common Shares represented by a
certificate have been registered under an effective registration statement filed
under the Securities Act , (b) a holder of Common Shares provides the Company
and its transfer agent with an opinion of counsel, in form, substance and scope
customary for opinions of counsel in comparable transactions, to the effect that
a public sale or transfer of such Common Shares may be made without registration
under the Securities Act and such sale either has occurred or may occur without
restriction on the manner of such sale or transfer, (c) such holder provides the
Company and its transfer agent with reasonable assurances that such Common
Shares can be sold under Rule 144, or (d) the Common Shares represented by a
certificate can be sold without restriction as to the number of securities sold
under Rule 144(k), the Company will permit the transfer of the Common Shares,
and the Company's transfer agent will issue one or more certificates, free from
any restrictive legend, in such name and in such denominations as specified by
such holder as soon as practicable. Notwithstanding anything herein to the
contrary, the Common Shares may be pledged as collateral in connection with a
bona fide margin account or other lending arrangement; provided that such pledge
will not alter the provisions of this Article V with respect to the removal of
restrictive legends.

      5.3   Enforcement of Provision. Nothing herein shall limit such Investor's
right to pursue actual damages for the Company's failure to deliver certificates
representing any Common Shares as required by this Agreement, and such Investor
shall have the right to pursue all remedies available to it at law or in equity
including, without limitation, a decree of specific performance and/or
injunctive relief. The Company acknowledges that a breach by it of its
obligations hereunder will cause irreparable harm to the Investor by vitiating
the intent and purpose of the transaction contemplated hereby. Accordingly, the
Company acknowledges that the remedy at law for a breach of its obligations
under this Article V will be inadequate and agrees, in the event of a breach or
threatened breach by the Company of the provisions of this Section, that the
Investor will be entitled, in addition to all other available remedies, to an
injunction restraining any breach and requiring immediate transfer of the Common
Shares, as applicable, without the necessity of showing economic loss and
without any bond or other security being required.

                                       12

<PAGE>

                                   ARTICLE VI
                 CONDITIONS TO THE COMPANY'S OBLIGATION TO SELL

      The obligation of the Company to issue and sell the Common Shares to each
Investor at the Closing is subject to the satisfaction by such Investor, on or
before the Closing Date, of each of the following conditions. These conditions
are for the Company's sole benefit and may be waived by the Company at any time
in its sole discretion:

      6.1   The Investor will have executed this Agreement, the Investor
Questionnaire and the Registration Rights Agreement and will have delivered
those agreements to the Company.

      6.2   The Investor will have delivered the Purchase Price for the Common
Shares to the Company in accordance with this Agreement.

      6.3   The representations and warranties of the Investor must be true and
correct in all material respects as of the Closing Date as though made at that
time (except for representations and warranties that speak as of a specific
date, which representations and warranties must be correct as of such date), and
the Investor will have performed and complied in all material respects with the
covenants and conditions required by this Agreement to be performed or complied
with by the Investor at or prior to the Closing.

      6.4   No statute, rule, regulation, executive order, decree, ruling or
injunction will have been enacted, entered, promulgated or endorsed by or in any
court or governmental authority of competent jurisdiction or any self-regulatory
organization having authority over the matters contemplated hereby which
prohibits the consummation of any of the transactions contemplated by this
Agreement or the Registration Rights Agreement.

                                  ARTICLE VII
               CONDITIONS TO THE INVESTOR'S OBLIGATION TO PURCHASE

      The obligation of each Investor hereunder to purchase the Common Shares
from the Company at the Closing is subject to the satisfaction, on or before the
Closing Date, of each of the following conditions. These conditions are for each
Investor's respective benefit and may be waived by any Investor at any time in
its sole discretion:

      7.1   The Company will have executed this Agreement, and the Registration
Rights Agreement and will have delivered those Agreements to the Investor.

      7.2   The Investors shall have received an opinion of counsel from
Stradling Yocca Carlson & Rauth, counsel to the Company, in customary form,
acceptable to Investors and their counsel.

      7.3   Each of the representations and warranties of the Company qualified
by materiality must be true and correct in all respects as of the Closing as
though made at that time (except for representations and warranties that speak
as of a specific date, which representations and warranties must be true and
correct as of such date) and each of the representations and warranties of the
Company not qualified by materiality must be true and correct in all material
respects as of the Closing as though made at that time (except for
representations and warranties that speak as of a specific date, which
representations and warranties must be true and correct as of such date) and the

                                       13

<PAGE>

Company must have performed and complied in all material respects with the
covenants and conditions required by this Agreement to be performed or complied
with by the Company at or prior to the Closing. The Investor must have received
a certificate or certificates dated as of the Closing Date and executed by the
Chief Executive Officer or the Chief Financial Officer of the Company certifying
as to the matters in contained in this Section 7.3 and as to such other matters
as may be reasonably requested by such Investor, including, but not limited to,
the Company's Certificate of Incorporation, Bylaws, Board of Directors'
resolutions relating to the transactions contemplated hereby and the incumbency
and signatures of each of the officers of the Company who may execute on behalf
of the Company any document delivered at the Closing.

      7.4   No litigation, statute, rule, regulation, executive order, decree,
ruling or injunction will have been enacted, entered, promulgated or endorsed by
or in any court or governmental authority of competent jurisdiction or any
self-regulatory organization having authority over the matters contemplated
hereby which prohibits the consummation of any of the transactions contemplated
by this Agreement or the Registration Rights Agreement and which could,
individually or in the aggregate, have a Material Adverse Effect.

      7.5   Trading and listing of the Common Stock on Nasdaq must not have been
suspended by the SEC or Nasdaq.

      7.6   Irrevocable transfer agent instructions, in form and substance
satisfactory to the Investors, will have been delivered to the Company's
transfer agent and acknowledged in writing by such transfer agent.

                                  ARTICLE VIII
                                 INDEMNIFICATION

      In consideration of each Investor's execution and delivery of this
Agreement and its acquisition of the Common Shares hereunder, and in addition to
all of the Company's other obligations under this Agreement and the Registration
Rights Agreement, the Company will defend, protect, indemnify and hold harmless
each Investor and each other holder of the Common Shares and all of their
stockholders, officers, directors, employees and direct or indirect investors
and any of the foregoing person's agents or other representatives (including,
without limitation, those retained in connection with the transactions
contemplated by this Agreement) (collectively, the "Indemnitees") from and
against any and all actions, causes of action, suits, claims, losses, costs,
penalties, fees, liabilities and damages, and expenses in connection therewith
(regardless of whether any such Indemnitee is a party to the action for which
indemnification hereunder is sought), and including reasonable attorneys' fees
and disbursements (the "Indemnified Liabilities"), incurred by an Indemnitee as
a result of, or arising out of, or relating to (a) any breach of any
representation or warranty made by the Company herein or in any other
certificate, instrument or document contemplated hereby or thereby, (b) any
breach of any covenant, agreement or obligation of the Company contained herein
or in any other certificate, instrument or document contemplated hereby or
thereby or (c) any cause of action, suit or claim brought or made against such
Indemnitee and arising out of or resulting from the execution, delivery,
performance, breach or enforcement of this Agreement or the Registration Rights
Agreement by the Company. To the extent that the foregoing undertaking by the
Company is unenforceable for any reason, the Company will make the maximum
contribution to the payment and satisfaction of each of the Indemnified
Liabilities that is permissible under applicable law.

                                       14

<PAGE>

      The Indemnitees shall have the right to employ separate counsel in any
such proceeding and to participate in the defense thereof, but the fees and
expenses of such counsel shall be at the expense of such Indemnitees unless: (i)
the Company has agreed in writing to pay such fees and expenses; (ii) the
Company shall have failed to promptly assume the defense of such proceeding and
to employ counsel reasonably satisfactory to such Indemnitees in any such
proceeding; or (iii) the named parties to any such proceeding (including any
impleaded parties) include both such Indemnitees and the Company, and such
Indemnitees shall have been advised by counsel that a conflict of interest is
likely to exist if the same counsel were to represent such Indemnitees and the
Company (in which case, if such Indemnitees notify the Company in writing that
they elect to employ separate counsel at the expense of the Company, the Company
shall not have the right to assume the defense thereof and such counsel shall be
at the reasonable expense of the Company; provided, however, that in no event
shall the Company be responsible for the fees and expenses of more than one
separate counsel). The Company shall not be liable for any settlement of any
such proceeding effected without its written consent, which consent shall not be
unreasonably withheld. The Company shall not, without the prior written consent
of a majority of the Indemnitees, effect any settlement of any pending
proceeding in respect of which Indemnitees are a party, unless such settlement
includes an unconditional release of such Indemnitees from all liabilities that
are the subject matter of such proceeding. Subject to the foregoing, all fees
and expenses (including reasonable fees and expenses to the extent incurred in
connection with investigating or preparing to defend any such proceeding in a
manner inconsistent with this Article VIII) of the Indemnitees shall be paid to
the Indemnitees as incurred, within ten (10) business days of written notice
thereof to the Company, which notice shall be delivered no more frequently than
on a monthly basis; provided, that the Indemnitees shall reimburse the Company
for any and all such fees and expenses to the extent it is finally judicially
determined that such Indemnitees are not entitled to indemnification hereunder.

                                   ARTICLE IX
                                   DEFINITIONS

      9.1   "Closing" means the closing of the purchase and sale of the Common
Shares under this Agreement.

      9.2   "Closing Date" has the meaning set forth in Section 1.3.

      9.3   "Common Shares" has the meaning set forth in the Recitals.

      9.4   "Common Stock" means the common stock, par value $.001 per share, of
the Company.

      9.5   "Company" means Sonus Pharmaceuticals, Inc.

      9.6   "Exchange Act" means the Securities Exchange Act of 1934, as
amended.

      9.7   "Indemnified Liabilities" has the meaning set forth in Article VIII.

      9.8   "Indemnitees" has the meaning set forth in Article VIII.

      9.9   "Investors" means the investors whose names are set forth on the
signature pages of this Agreement, and their permitted transferees.

                                       15

<PAGE>

      9.10  "Material Adverse Effect" means a material adverse effect on (a) the
business, operations, prospects, assets or financial condition of the Company or
(b) the ability of the Company to perform its obligations pursuant to the
transactions contemplated by this Agreement or under the agreements or
instruments to be entered into or filed in connection herewith, including the
Registration Rights Agreement.

      9.11  "Nasdaq" means the Nasdaq National Market System.

      9.12  "Registration Rights Agreement" means the Registration Rights
Agreement, dated as of the date of this Agreement and among the parties to this
Agreement, in the form attached hereto as Exhibit C.

      9.13  "Regulation D" means Regulation D as promulgated under by the SEC
under the Securities Act .

      9.14  "Rule 144" and "Rule 144(k)" mean Rule 144 and Rule 144(k),
respectively, promulgated under the Securities Act , or any successor rule.

      9.15  "SEC" means the United States Securities and Exchange Commission.

      9.16  "SEC Documents" has the meaning set forth in Section 3.6.

      9.17  "Common Shares" has the meaning set forth in the Recitals.

      9.18  "Securities Act " means the Securities Act of 1933, as amended, and
the rules and regulations thereunder, or any similar successor statute.

                                   ARTICLE X
                          GOVERNING LAW; MISCELLANEOUS

      10.1  Governing Law; Jurisdiction; Jury Trial Waiver. This Agreement will
be governed by and interpreted in accordance with the laws of the State of
Delaware without regard to the principles of conflict of laws. The parties
hereto hereby submit to the exclusive jurisdiction of the United States federal
and state courts located in the State of Delaware with respect to any dispute
arising under this Agreement, the agreements entered into in connection herewith
or the transactions contemplated hereby or thereby. EACH PARTY HEREBY
IRREVOCABLY WAIVES ANY RIGHT THAT IT MAY HAVE TO, AND AGREES NOT TO REQUEST, A
JURY TRIAL FOR THE ADJUDICATION OF ANY DISPUTE HEREUNDER OR IN CONNECTION
HEREWITH OR WITH ANY TRANSACTION CONTEMPLATED HEREBY.

      10.2  Counterparts; Signatures by Facsimile. This Agreement may be
executed in two or more counterparts, all of which are considered one and the
same agreement and will become effective when counterparts have been signed by
each party and delivered to the other parties. This Agreement, once executed by
a party, may be delivered to the other parties hereto by facsimile transmission
of a copy of this Agreement bearing the signature of the party so delivering
this Agreement.

      10.3  Headings. The headings of this Agreement are for convenience of
reference only, are not part of this Agreement and do not affect its
interpretation.

                                       16

<PAGE>

      10.4  Severability. If any provision of this Agreement is invalid or
unenforceable under any applicable statute or rule of law, then such provision
will be deemed modified in order to conform with such statute or rule of law.
Any provision hereof that may prove invalid or unenforceable under any law will
not affect the validity or enforceability of any other provision hereof.

      10.5  Entire Agreement; Amendments. This Agreement and the Registration
Rights Agreement (including all schedules and exhibits thereto) constitute the
entire agreement among the parties hereto with respect to the subject matter
hereof and thereof. There are no restrictions, promises, warranties or
undertakings, other than those set forth or referred to herein or therein. This
Agreement supersedes all prior agreements and understandings among the parties
hereto with respect to the subject matter hereof. No provision of this Agreement
may be waived or amended other than by an instrument in writing signed by the
party to be charged with enforcement.

      10.6  Notices. Any notices required or permitted to be given under the
terms of this Agreement must be sent by certified or registered mail (return
receipt requested) or delivered personally or by courier (including a recognized
overnight delivery service) or by facsimile and will be effective five days
after being placed in the mail, if mailed by regular U.S. mail, or upon receipt,
if delivered personally, by courier (including a recognized overnight delivery
service) or by facsimile, in each case addressed to a party. The addresses for
such communications are:

      If to the Company:             Chief Financial Officer
                                     Sonus Pharmaceuticals, Inc.
                                     22026 20th Avenue S.E.
                                     Bothell, Washington 98021
                                     Fax: (425) 489-0626

      With copies to:                K.C. Schaaf, Esq.
                                     Stradling Yocca Carlson & Rauth
                                     660 Newport Center Drive, Suite 1600
                                     Newport Beach, California 92660
                                     Fax: (949) 725-4100

      If to an Investor: To the address set forth immediately below such
Investor's name on the signature pages hereto.

      Each party will provide written notice to the other parties of any change
in its address in accordance with the notice provisions hereof.

      10.7  Successors and Assigns. This Agreement is binding upon and inures to
the benefit of the parties and their successors and assigns. The Company will
not assign this Agreement or any rights or obligations hereunder without the
prior written consent of the Investors, and no Investor may assign this
Agreement or any rights or obligations hereunder without the prior written
consent of the Company. Notwithstanding the foregoing, an Investor may assign
all or part of its rights and obligations hereunder to any of its "affiliates,"
as that term is defined under the Securities Act , without the consent of the
Company so long as the affiliate is an accredited investor (within the meaning
of Regulation D under the Securities Act ) and agrees in writing to be bound by
this Agreement. This provision does not limit the Investor's right to transfer
the Common Shares

                                       17

<PAGE>

pursuant to the terms of this Agreement or to assign the Investor's rights
hereunder to any such transferee pursuant to the terms of this Agreement.

      10.8  Third Party Beneficiaries. This Agreement is intended for the
benefit of the parties hereto and their respective permitted successors and
assigns, and, except as contemplated in Section 2.10, is not for the benefit of,
nor may any provision hereof be enforced by, any other person.

      10.9  Survival. The representations and warranties of the Company and the
agreements and covenants set forth herein will survive the Closing hereunder for
a period of twelve (12) months. The Company makes no representations or
warranties in any oral or written information provided to Investors, other than
the representations and warranties included herein.

      10.10 Further Assurances. Each party will do and perform, or cause to be
done and performed, all such further acts and things, and will execute and
deliver all other agreements, certificates, instruments and documents, as
another party may reasonably request in order to carry out the intent and
accomplish the purposes of this Agreement and the consummation of the
transactions contemplated hereby.

      10.11 No Strict Construction. The language used in this Agreement is
deemed to be the language chosen by the parties to express their mutual intent,
and no rules of strict construction will be applied against any party.

      10.12 Equitable Relief. The Company recognizes that, if it fails to
perform or discharge any of its obligations under this Agreement, including
specifically, but without limitation, under Section 4.10, any remedy at law may
prove to be inadequate relief to the Investors. The Company therefore agrees
that the Investors are entitled to seek temporary and permanent injunctive
relief in any such case.

                                       18

<PAGE>

      IN WITNESS WHEREOF, the undersigned Investors and the Company have caused
this Securities Purchase Agreement to be duly executed as of the date first
above written.

                                        COMPANY:

                                        SONUS PHARMACEUTICALS, INC.

                                            By: /s/ Michael A. Martino
                                                --------------------------------
                                            Name: Michael A. Martino
                                            Title: President & CEO

                                       19

<PAGE>

                            OMNIBUS SIGNATURE PAGE TO
                           SONUS PHARMACEUTICALS, INC.
                          SECURITIES PURCHASE AGREEMENT

      The undersigned hereby executes and delivers the Securities Purchase
Agreement to which this Signature Page is attached, which, together with all
counterparts of the Agreement and Signature Pages of the other parties named in
said Agreement, shall constitute one and the same document in accordance with
the terms of the Agreement.

                                    Entity Name: _______________________________

                                    Sign Name:   _______________________________

                                    Print Name:  _______________________________

                                    Title:       _______________________________

                                    Address:     _______________________________
                                                 _______________________________
                                                 _______________________________

                                    Telephone:   _______________________________
                                    Facsimile:   _______________________________

                                    Number of Common Shares Purchased: _________

                                    Federal Tax ID (if applicable) _____________

                                       20

<PAGE>

                              SCHEDULE OF INVESTORS

                                       21

<PAGE>

                                    EXHIBIT A

                           WIRE TRANSFER INSTRUCTIONS
                                       FOR
                              SONUS PHARMACEUTICALS

FED WIRE INSTRUCTIONS:    Wells Fargo Bank, San Francisco
                          ABA #121000248
                          WFB Acct: #4068-000769 (Wells Capital)
                          SWIFT Code  WFBIUS6S
                          FFC: A/C #129984 Sonus Pharmaceuticals
                          Attn: Mora Andrews

                                      A-1

<PAGE>

                                    EXHIBIT B

                             INVESTOR QUESTIONNAIRE

I CERTIFY THAT I AM AN ACCREDITED INVESTOR BECAUSE I FALL WITHIN ONE OF THE
FOLLOWING CATEGORIES.

____ A natural person whose individual net worth, or joint net worth with that
person's spouse, at the time of his purchase exceeds $1,000,000;

____ A natural person who had "Individual Income" in excess of $200,000 in each
of the two most recent years or joint income with that person's spouse in excess
of $300,000 in each of those years and has a reasonable expectation of reaching
the same income level in the current year;

____ An employee benefit plan within the meaning of the Employee Retirement
Income Security Act of 1974, and the investment decision is made by a plan
fiduciary, as defined in Section 3(21) of such act, which is either a bank,
savings and loan association, insurance company or registered investment advisor
or if the employee benefit plan has total assets in excess of $5,000,000, or, if
a self-directed plan, with investment decisions made solely by persons that are
Accredited Investors;

____ A bank as defined in Section 3(a)(2) of the Securities Act , or any savings
and loan association or other institution as defined in Section 3(a)(5)(A) of
the Securities Act , whether acting in its individual or fiduciary capacity;

____ A broker or dealer registered pursuant to Section 15 of the Securities
Exchange Act of 1934, as amended;

____ An insurance company as defined in Section 2(13) of the Securities Act ;

____ An investment company registered under the Investment Company Act of 1940
or a business development company as defined in Section 2(a)(48) of that Act;

____ A Small Business Investment Company licensed by the U.S. Small Business
Administration under Section 301(c) or (d) of the Small Business Investment Act
of 1958;

____ A plan established and maintained by a state, its political subdivisions,
or any agency or instrumentality of a state or its political subdivisions, for
the benefit of its employees, if such plan has total assets in excess of
$5,000,000;

____ A private business development company as defined in Section 202(a)(22) of
the Investment Advisers Act of 1940;

____ An organization described in Section 501(c)(3) of the Internal Revenue
Code, corporation, Massachusetts or similar business trust, or partnership, not
formed for the specific purpose of acquiring the securities offered, with total
assets in excess of $5,000,000;

____ A director, executive officer, or general partners of the issuer of the
securities being offered or sold, or any director, executive officer, or general
partner of a general partner of that issuer;

                                      B-1

<PAGE>

___ A trust, with total assets in excess of $5,000,000, not formed for the
specific purpose of acquiring the securities offered, whose purchase is directed
by a sophisticated person who has such knowledge and experience in financial and
business matters that such person is capable of evaluating the merits and risks
of investing in the Company; or

____ An entity in which all of the equity owners qualify under any of the above
subparagraphs.

NET WORTH. The term "net worth" means the excess of total assets over total
liabilities. In calculating net worth, the stockholder may include the estimated
fair market value of the stockholder's principal residence as an asset.

INCOME. In determining individual "income," the stockholder should add to the
stockholder's individual taxable adjusted gross income (exclusive of any spousal
income) any amounts attributable to tax exempt income received, losses claimed
as a limited partner in any limited partnership, deductions claimed for
depletion, contributions to an IRA or Keogh retirement plan, alimony payments,
and any amount by which income from long-term capital gains has been reduced in
arriving at adjusted gross income.

Dated: ___________, 2004                    ___________________________________

                                      B-2

<PAGE>

                                    EXHIBIT C

                          REGISTRATION RIGHTS AGREEMENT

                                      C-1