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                                                                    EXHIBIT 10.5

                                    EXHIBIT C

                            PATENT LICENSE AGREEMENT

     This Patent License Agreement (this "Agreement") is made and entered into
effect this 30th day of September, 2005, by and between Abbott Laboratories, a
corporation organized and existing under the laws of the State of Illinois and
having a principal place of business at 100 Abbott Park Road, Abbott Park,
Illinois 60064 ("Abbott") and ImaRx Therapeutics Inc., a corporation organized
and existing under the laws of Delaware and having a principal place of business
at Tucson, Arizona ("Licensee").

     WHEREAS, pursuant to that certain Asset Purchase Agreement between Abbott
and Licensee, dated September 30, 2005 (the "Asset Purchase Agreement"), Abbott
has agreed to sell to Licensee, and Licensee has agreed to purchase from Abbott,
the Purchased Assets (as defined in the Asset Purchase Agreement);

     WHEREAS, in connection with its purchase of the Purchased Assets from
Abbott, Licensee desires to obtain a license under certain of Abbott's patents;
and

     WHEREAS, Abbott and Licensee have agreed to enter into this Agreement as a
condition to the closing of the transactions contemplated by the Asset Purchase
Agreement.

     NOW THEREFORE, in consideration of the promises and the mutual covenants
set forth herein and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto hereby agree
and covenant as follows.

                             ARTICLE I. DEFINITIONS

     The following terms, when used herein with initial capital letters, shall
have the respective meanings set forth in this Article I. Capitalized terms used
but not defined herein shall have the meanings set forth in the Asset Purchase
Agreement.

1.1  "Affiliate" means, with respect to any Person, any other Person directly or
     indirectly controlling or controlled by, or under direct or indirect common
     control with, such Person. For purposes of this definition, a Person shall
     be deemed to control another Person if it owns or controls more than fifty
     percent (50%) of the voting equity of the other Person (or other comparable
     ownership if the Person is not a corporation).

1.2  "Asset Purchase Agreement" shall have the meaning provided in the Preamble.

1.3  "Field" means the business of manufacturing, marketing and selling
     thrombolytic pharmaceutical therapy products, which shall mean serine
     proteases that convert plasminogen to plasmin to break down the fibrinogen
     and fibrin to dissolve a thrombus in an artery, vein or in-dwelling
     catheter, or any proteases or protease activators which catalyze
     proteolytic breakdown of fibrinogen or fibrin for the same purpose.

1.4  "Licensed Patents" means only the following: (i) U.S. Patent No. 5,665,578
     issued September 9, 1997, entitled Vector and Method for Achieving High
     Level of Expression

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     in Eukaryotic Cells (the "Gillies Patent") and (ii) U.S. Patent No.
     5,741,682 issued April 21, 1998, entitled Expression Induction Method (the
     "Lo Patent").

1.5  "Licensed Products" means any products that would, but for the license
     granted in Section 2.1, infringe a valid claim of any patent included in
     the Licensed Patents.

1.6  "Person" means any individual, corporation, partnership, joint venture,
     limited liability company, trust or unincorporated organization or
     government or any agency or political subdivision thereof.

1.7  "Plaintiff" shall have the meaning provided in Section 3.2.

1.8  "Territory" means, for any patent included in the Licensed Patents, only
     that country in which such patent was issued.

                              ARTICLE II. LICENSE

2.1  License Grant.

     a.   Abbott hereby grants to Licensee during the term of this Agreement an
          exclusive (even as to Abbott), assignable, transferable, fully
          paid-up, royalty-free license, with the right to sublicense in
          multiple tiers, to make, have made, distribute, use, offer to sell,
          and import Licensed Products and to practice the Gillies Patent solely
          in the Field, throughout the Territory.

     b.   Abbott hereby grants to Licensee during the term of this Agreement an
          exclusive (even as to Abbott), assignable, transferable, fully
          paid-up, royalty-free license, with the right to sublicense in
          multiple tiers, to make, have made, distribute, use, offer to sell,
          and import Licensed Products and to practice the Lo Patent solely in
          the Field, throughout the Territory.

2.2  Marking Requirements. Licensee shall mark or label all Licensed Products
     with appropriate patent markings as Abbott reasonably requests from time to
     time during the term of this Agreement and shall otherwise comply with all
     applicable United States and foreign jurisdiction laws relating to patent
     marking.

2.3  Reservation of Rights. Except for the express licenses granted in Section
     2.1, Abbott shall retain all right, title and interest in and to the
     Licensed Patents. No other rights or licenses, express or implied, are
     granted by this Agreement. Notwithstanding the licenses granted in Section
     2.1, Abbott and its Affiliates and licensees shall (i) retain the right to
     practice the Licensed Patents, outside of the Field, and (ii) have the
     right, at their option, to license for use outside the Field any
     improvement patents relating to the Licensed Patents ("Improvements")
     obtained by Licensee and its Affiliates (the "Option"). Licensee and its
     Affiliates shall not license any Improvements outside the Field to any
     third party without first offering such license to Abbott. If Abbott and
     Licensee or its Affiliates do not enter into a binding agreement with
     respect to such license after negotiation in good faith within sixty (60)
     days following the date of such notice, Licensee or its Affiliate may
     thereafter grant such license to a third party, but on terms no


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     more favorable to the third-party licensee than the terms offered to
     Abbott. Licensee shall notify Abbott of Improvements within sixty (60) days
     of issuance.

2.4  Acknowledgement. Licensee acknowledges the validity of the Licensed
     Patents. To the fullest extent possible under applicable law, in the event
     Licensee elects to challenge the validity of one or more Licensed Patents,
     for example, by initiating re-examination, or declaratory judgment actions,
     or any other type of court action, or any other legal or administrative
     proceeding, including proceedings or actions in foreign patent offices or
     courts, Abbott shall have the right to immediately terminate this Agreement
     and all licenses granted herein.

2.5  Regulatory Compliance. Licensee shall be solely responsible, at its own
     expense, for the preparation, filing and prosecution of, and for obtaining
     and maintaining, all applicable regulatory approvals for the manufacture,
     marketing, promotion or sale of Licensed Products in each country in the
     Territory, including without limitation, any approval required from the
     United States Food and Drug Administration.

                 ARTICLE III. PATENT PROSECUTION AND LITIGATION

3.1  Prosecution and Maintenance. Abbott shall have the exclusive right, but not
     the obligation (except as set forth in this Section 3.1), to prepare, file,
     prosecute and maintain all Licensed Patents, including, without limitation,
     conducting any interferences, reissues or reexamination or applying for all
     patent term extensions, in the Territory. Licensee shall, upon request by
     Abbott and at Abbott's expense, cooperate in connection with the
     preparation, filing, prosecution and maintenance of all Licensed Patents.
     Prior to allowing any of the Licensed Patents to lapse, Abbott shall give
     Licensee notice and the reasonable opportunity to pay any fees and expenses
     necessary to maintain such Licensed Patent. Upon Abbott's receipt of such
     fees, Abbott will continue to maintain said Licensed Patent in Abbott's
     name.

3.2  Infringements.

     a.   Notice. Upon learning of the actual or potential infringement of a
          Licensed Patent in the Territory, Abbott or Licensee, as the case may
          be, shall promptly provide notice to the other party in writing of
          such infringement and shall supply the other party with all evidence
          related thereto in its possession.

     b.   Enforcement. Except as expressly provided herein, (i) in connection
          with any violation or infringement of the Licensed Patents by a
          perceived violator or infringer conducting business or utilizing
          technology outside the Field as defined above, Abbott shall have the
          sole, undivided and exclusive right, but not the obligation, to
          institute or bring, and control, any suits or actions and (ii) in
          connection with any violation or infringement of the Licensed Patents
          by a perceived violator or infringer conducting business or utilizing
          technology within the Field as defined above, Licensee shall have the
          exclusive right, but not the obligation, to institute or bring, and
          control, any suits or actions, provided that Licensee shall consult
          with Abbott at Abbott's request with respect to any such suit or
          action and shall give due consideration to all suggestions and
          comments made by Abbott in connection


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          therewith. Each suit or action under this subsection (b) shall be
          maintained and conducted solely at the cost and expense of the party
          instituting such suit or action (the "Plaintiff"); provided that the
          other party shall reasonably cooperate in the prosecution of such suit
          or action (at the expense of the Plaintiff), including, without
          limitation, by joining as a nominal party thereto for purposes of
          standing and/or assigning to Plaintiff any claims and damages arising
          under the Licensed Patents against such defendant, and the Plaintiff
          shall keep the other party updated with respect to any such action.
          Each party shall have the right, but not the obligation, to
          participate and be represented in any suit or action involving the
          Licensed Patents instituted by the other party, by its own counsel at
          its own expense.

     c.   Settlements. Either party, as Plaintiff, shall be permitted to settle
          or consent to an adverse judgment in any suit or action in accordance
          with Section 3.2(b) without obtaining consent from the other party,
          unless any such settlement or consent judgment would either (i)
          obligate the other party to pay money or (ii) limit the scope of,
          invalidate or adversely affect the status or value of any Licensed
          Patent, in which event the Plaintiff shall obtain the other party's
          prior written consent (such consent not to be unreasonably withheld or
          delayed).

     d.   Awards and Damages. The Plaintiff shall be entitled to retain any and
          all amounts that may be received, collected or recovered in any suit
          or action instituted or brought under this Section 3.2, whether by
          judgment, settlement or otherwise.

                     ARTICLE IV. CONFIDENTIALITY; PUBLICITY

4.1  Confidential Information. All disclosures of confidential information made
     pursuant to this Agreement shall be governed by the Confidentiality
     Agreement between the parties dated May 6, 2005, as modified by Section
     12.3 of the Asset Purchase Agreement.

4.2  No Publicity. Except as expressly permitted under this Agreement or other
     written agreement between the parties, neither Licensee nor its Affiliates
     shall use the name or trademarks of Abbott, or any of Abbott's Affiliates,
     without Abbott's prior written consent. No press release related to this
     Agreement, or other announcement to the customers or suppliers of Abbott
     will be issued without the joint approval of Abbott and Licensee, except
     that: (i) Abbott or Licensee may make any public disclosure that such party
     in its good faith judgment believes is required by law or by any stock
     exchange or interdealer quotation system on which its securities are listed
     or quoted (in which case the party making the disclosure will use its
     commercially reasonable efforts to consult with the other party prior to
     making any such disclosure); and (ii) Abbott may make an announcement
     related to this Agreement to its employees.

                   ARTICLE V. REPRESENTATIONS AND WARRANTIES

5.1  Mutual Representations. Abbott hereby represents and warrants to Licensee,
     and Licensee on behalf of itself and its Affiliates, hereby represents and
     warrants to Abbott, that: (i) it is a corporation duly organized, validly
     existing and in good standing under the laws of the jurisdiction of its
     incorporation; (ii) it has full corporate power and authority to execute,
     deliver and perform its obligations under this Agreement; (iii) the


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     execution and delivery of this Agreement and the performance of all of its
     obligations hereunder have been duly authorized by all necessary company
     action; (iv) the signing, delivery and performance of this Agreement is not
     prohibited or limited by, and will not result in the breach of or a default
     under, any provision of its articles of incorporation or by-laws, or of any
     material agreement or instrument binding on it, or of any applicable order,
     writ, injunction or decree of any court or governmental instrumentality;
     and (v) this Agreement has been duly executed and delivered by it and
     constitutes its legal, valid and binding obligation.

5.2  Licensee's Representations and Warranties. Licensee hereby represents and
     warrants to Abbott that it shall comply with all applicable laws, rules,
     regulations, ordinances, permits and licenses when exercising its rights
     under this Agreement, including, without limitation, in the manufacture,
     marketing, promotion and sale of Licensed Products.

5.3  Abbott's Representations and Warranties: Abbott hereby represents and
     warrants to Licensee that it is the owner of the Licensed Patents and that
     it has the authority to grant the licenses provided herein, and that to the
     best of its Knowledge the exercise of the rights granted to Licensee
     hereunder will not infringe upon the intellectual property rights of any
     third party.

5.4  Disclaimer. THE LICENSED PATENTS ARE PROVIDED "AS IS." EXCEPT AS EXPRESSLY
     PROVIDED IN THIS ARTICLE V, ABBOTT AND LICENSEE MAKE NO WARRANTIES,
     EXPRESS, OR IMPLIED, AND EXPRESSLY DISCLAIM ALL WARRANTIES, INCLUDING,
     WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR
     A PARTICULAR PURPOSE AND NON-INFRINGEMENT, ANY EXPRESS OR IMPLIED
     WARRANTIES RELATED TO EFFICACY, SAFETY OR HEALTH BENEFITS AND ANY IMPLIED
     WARRANTIES ARISING OUT OF TRADE USAGE OR PRACTICE, COURSE OF DEALING OR
     COURSE OF PERFORMANCE.

5.5  Limitations of Liability. EXCEPT FOR DAMAGES RESULTING FROM BREACH OF ITS
     CONFIDENTIALITY OBLIGATIONS, IN NO EVENT SHALL EITHER PARTY BE LIABLE TO
     THE OTHER UNDER ANY THEORY OF LIABILITY FOR ANY INDIRECT, SPECIAL,
     PUNITIVE, INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY KIND, INCLUDING,
     WITHOUT LIMITATION, LOSS OF USE, INTERRUPTION OF BUSINESS, LOSS OF PROFITS,
     OR LOSS OF DATA OR INFORMATION, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
     DAMAGES.

5.6  Insurance. Licensee shall carry and maintain, during the term of this
     Agreement and for five (5) years thereafter, broad form comprehensive
     general liability insurance that includes without limitation, coverage for
     contractual liability, premises, operations, products liability, personal
     injury and death, advertising injury liability and broad form property
     damage liability, in amounts reasonable and customary in the pharmaceutical
     industry for entities of comparable size and comparable activities, but in
     no event less than Five Million Dollars ($5,000,000) per occurrence and Ten
     Million Dollars ($10,000,000) in the annual aggregate. These limits of
     coverage shall not be construed as a limitation of any liability of
     Licensee hereunder. Licensee shall have Abbott named as an additional
     insured on such policies. Licensee shall, within thirty (30) days after the


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     date of this Agreement, provide to Abbott a Certificate of Insurance
     evidencing such insurance coverage and that further provides that such
     policies may not be materially changed or canceled without at least sixty
     (60) days' prior written notice to Abbott.

                        ARTICLE VI. TERM AND TERMINATION

6.1  Term. Unless earlier terminated in accordance with the terms herein, the
     term of this Agreement shall commence on the Effective Date and shall
     remain in effect until the expiration of the last-to-expire valid claim of
     any patent included in the Licensed Patents.

6.2  Termination Without Cause. Licensee may terminate this Agreement at any
     time and for any reason upon written notice to Abbott. This Agreement may
     be terminated by mutual written agreement of the parties hereto.

6.3  Termination for Cause. This Agreement may be terminated prior to its
     expiration in accordance with the following provisions:

     a.   Breach. Either party may terminate this Agreement upon thirty (30)
          days prior written notice to the other party in the event the other
          party fails to perform any of its obligations hereunder or otherwise
          breaches any of its representations or warranties or fails to perform
          any of its covenants in this Agreement and if such breach or failure
          is not cured during such thirty day period. Without limiting the
          generality of the foregoing, violation of the scope of the license
          granted in Section 2.1 or breach of the provisions of Sections 2.2, ,
          2.5 or Article IV shall be deemed material breaches for which a party
          may terminate this Agreement according to this subsection (a).

     b.   Adverse Effect. If this Agreement shall be determined by a court,
          administrative or governmental body or authority of competent
          jurisdiction to be in violation of any applicable law, the party
          adversely affected by the ruling (which may be either party or both)
          may elect to terminate this Agreement upon thirty (30) days notice to
          the other party.

6.4  Effect of Termination.

     a.   Termination of License. Upon termination of this Agreement for any
          reason prior to the term set forth in Section 6.1, the license granted
          in Section 2.1 shall immediately terminate and Licensee shall
          immediately cease all activities under the Licensed Patents, including
          without limitation, the manufacture, marketing, promotion or sale of
          Licensed Products.

     b.   Further Assurances. Upon expiration or termination of this Agreement,
          Licensee shall execute all documents regarding the Licensed Patents
          that Abbott shall reasonably request. Abbott shall bear all expenses
          reasonably incurred in preparing and recording any such documents.

     c.   Survival. The expiration or termination of this Agreement shall not
          affect any rights or obligations of the parties that have accrued
          prior to such expiration or termination.


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          The following provisions shall survive expiration or termination of
          this Agreement for any reason: Article III, Section 6.4, Article IV,
          Article V and Article VII.

                           ARTICLE VII. MISCELLANEOUS

7.1  Entire Agreement; Amendment. This Agreement and the Asset Purchase
     Agreement constitute the entire agreement between the parties regarding the
     subject matter of this Agreement, and supersede all other prior agreements,
     understandings and negotiations, both written and oral, among the parties
     with respect to the subject matter of this Agreement. This Agreement may
     not be amended except by an instrument in writing signed by a duly
     authorized officer or representative of each of the parties hereto.

7.2  Successors. The terms and conditions of this Agreement shall be binding
     upon, and shall inure to the benefits of, the parties hereto and their
     respective permitted successors and assigns.

7.3  Governing Law/Jurisdiction. This Agreement shall be governed by and
     construed in accordance with, and the legal relations between the parties
     hereto shall be determined in accordance with, the laws of the State of
     Delaware, United States, without regard to any laws relating to conflict of
     laws. The parties agree that the United Nations Convention of Contracts for
     the International Sale of Goods is specifically excluded from application
     to this Agreement.

7.4  Injunctive Relief; Specific Performance. The parties hereto acknowledge and
     agree that any breach of the terms of this Agreement could give rise to
     irreparable harm for which money damages would not be an adequate remedy
     and accordingly the parties agree that, in addition to any other remedies,
     each party shall be entitled to obtain preliminary or injunctive relief and
     to enforce the terms of this Agreement by a decree of specific performance.

7.5  Relationship of Parties. Nothing in this Agreement shall be construed to
     create a partnership, agency, joint venture, franchise or employer-employee
     relationship between the parties. Neither party shall be responsible for
     the compensation, payroll-related taxes, workers' compensation, accident or
     health insurance or other benefits of employees of the other party. Neither
     party shall have any authority to bind the other party unless expressly
     agreed in a separate writing.

7.6  No Third Party Beneficiaries. This Agreement shall not be deemed to confer
     any rights or remedies upon any person not a party hereto.

7.7  Notices. All communications, notices and consents provided for herein shall
     be in writing and be given in person or by means of telex, facsimile or
     other means of wire transmission (with request for assurance of receipt in
     a manner typical with respect to communications of that type), by overnight
     courier or by mail, and shall become effective: (a) on delivery if given in
     person; (b) on the date of transmission if sent by telex, facsimile or
     other means of wire transmission; (c) one (1) business day after delivery
     to the overnight service; or (d) four (4) business days after being
     deposited in the


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     United States mails, with proper postage and documentation, for first-class
     registered or certified mail, prepaid.

          Notices shall be addressed as follows:

     If to Licensee, to:   ImaRx Therapeutics
                         1635 East 18th Street
                         Tucson, AZ 85719
                         Attn: Greg Cobb
                         Facsimile Number: 520-791-2437

     with copies to:     DLA Piper Rudnick Gray Cary LLP
                         701 Fifth Avenue
                         Suite 7000
                         Seattle, WA 98104
                         Attn: Jeffrey E. Harmes
                         John M. Steel
                         Facsimile Number: 206-839-4801
     If to Abbott, to:

                         Abbott Laboratories
                         100 Abbott Park Road
                         Building AP6D, Department 364
                         Abbott Park, Illinois  60064-6020
                         Attn: General Counsel
                         Facsimile Number: (847) 938-6277

     with copies to:
                         Kirkland & Ellis LLP
                         200 East Randolph Drive
                         Chicago, Illinois  60601
                         Attn: R. Scott Falk, P.C. & Stacey T. Kern
                         Facsimile Number: (312) 861-2200

provided, however, that if any party shall have designated a different address
by notice to the others, then to the last address so designated.

7.8  Severability. The provisions of this Agreement are severable, and the
     unenforceability of any provision of this Agreement shall not affect the
     enforceability of the remainder of this Agreement. In the event that any
     provision of this Agreement is determined by a court to be unenforceable as
     drafted, that provision shall be construed so as to effectuate the purposes
     of that provision to the greatest extent possible under applicable law.

7.9  No Waiver. The failure of either party to exercise any right or to demand
     the performance by the other party of duties required hereunder shall not
     constitute a waiver of any rights or obligations provided for herein.


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7.10 Counterparts. This Agreement may be executed in multiple counterparts, each
     of which shall be deemed an original and all of which together shall
     constitute one and the same instrument.

7.11 Construction. The language in all parts of this Agreement shall be
     construed, in all cases, according to its fair meaning. The parties
     acknowledge that each party and its counsel have reviewed and revised this
     Agreement and that any rule of construction to the effect that any
     ambiguities are to be resolved against the drafting party shall not be
     employed in the interpretation of this Agreement. Words in the singular
     shall be deemed to include the plural and vice versa and words of one
     gender shall be deemed to include the other gender as the context requires.
     The terms "hereof," "herein," and "herewith" and words of similar import
     shall, unless otherwise stated, be construed to refer to this Agreement as
     a whole and not to any particular provision of this Agreement. Article and
     Section references are to the Articles and Sections to this Agreement
     unless otherwise specified. Unless otherwise stated, all references to any
     agreement shall be deemed to include the exhibits, schedules and annexes to
     such agreement. The word "including" and words of similar import when used
     in this Agreement shall mean "including, without limitation," unless the
     context otherwise requires or unless otherwise specified. The word "or"
     shall not be exclusive. Unless otherwise specified in a particular case,
     the word "days" refers to calendar days. References herein to this
     Agreement or any other agreement shall be deemed to refer to this Agreement
     or such other agreement as of the date of such agreement and as it may be
     amended thereafter, unless otherwise specified.

7.12 Captions. The captions and headings in this Agreement are inserted for
     convenience and reference only and in no way define or limit the scope or
     content of this Agreement and shall not affect the interpretation of its
     provisions.

                                      * * *


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     IN WITNESS WHEREOF, each of the parties, acting through its duly authorized
representative, signs this Agreement on the date indicated.

ABBOTT LABORATORIES                     IMARX THERAPEUTICS, INC.


By: /s/ Sean E. Murphy                  By: /s/ Evan Unger
    ---------------------------------       ------------------------------------
Print Name: Sean E. Murphy              Print Name: Evan Unger
Title: Vice President Global            Title: President and CEO
       Licensing/New Business
       Development

Date: 9/30/05                           Date: 9-30-05