ROYALTY ASSIGNMENT TERMINATION AGREEMENT

Exhibit 10.24

ROYALTY ASSIGNMENT TERMINATION AGREEMENT

THIS ROYALTY ASSIGNMENT TERMINATION AGREEMENT (this “Agreement”) is made as of November 17, 2010, by and among ACCENTIA BIOPHARMACEUTICALS, INC., a Florida corporation (“Accentia”), BIOVEST INTERNATIONAL, INC., a Delaware corporation (“Biovest”), ERATO CORP. (“Erato”), VALENS U.S. SPV I, LLC (“Valens U.S.”), VALENS OFFSHORE SPV I, LTD. (“Valens Offshore”), and PSOURCE STRUCTURED DEBT LIMITED (“PSource” and together with Erato, Valens U.S. and Valens Offshore, the “Assignees”).

RECITALS

WHEREAS, pursuant to that certain Term Loan and Security Agreement (the “Security Agreement”) dated as of November 17, 2010, by and among Biovest, the Lenders party thereto and LV Administrative Services, Inc., the parties hereto, in consideration for the acceptance by certain of the Prepetition Lenders of the allowed secured claims against Biovest as provided therein, have agreed, among other things, to the modification of the Biovest Royalty;

WHEREAS, Accentia and Biovest have entered into four (4) separate Assignment of Rights Under Royalty Agreements, each dated as of June 18, 2008, with each of the Assignees (collectively, the “Royalty Assignment Agreements”);

WHEREAS, pursuant to the Royalty Assignment Agreements, Accentia assigned and transferred to the Assignees, collectively, 4.00% of the royalty of 19.50% granted to Accentia by Biovest pursuant to that certain Royalty Agreement by and between Biovest and Accentia dated as of October 31, 2006, as amended;

WHEREAS, in order to modify the Biovest Royalty in accordance with the Security Agreement, the Royalty Assignment Agreements must be terminated; and

WHEREAS, in connection with the modification of the Biovest Royalty and pursuant to the terms and conditions of the Security Agreement and the Confirmed Plan, the parties hereto hereby desire to terminate the Royalty Assignment Agreements effective as of the date of this Agreement.

NOW, THEREFORE, for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto hereby agree as follows:

1.        Capitalized terms used but not defined herein shall have the meanings ascribed to them in the Security Agreement.

2.        The parties hereto agree that the above Recitals are true and correct in all respects.

3.        The parties hereto hereby consent to the termination of the Royalty Assignment Agreements (and all of the rights and obligations created thereunder) effective as of the date of this Agreement.

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4.        Each of the Assignees hereby acknowledges and agrees that it shall have no claims of any nature whatsoever against Biovest or Accentia as a result of the termination of the Royalty Assignment Agreements.

5.        This Agreement shall be binding upon the parties hereto and their respective successors and assigns. The parties hereto agree that this Agreement is fully and adequately supported by consideration, is fair and reasonable, and that they have had the opportunity to discuss this matter with counsel of their choice. This Agreement may be executed in one or more counterparts, each of which shall be deemed an original and all of which together shall be deemed to constitute one agreement. It is understood and agreed that if facsimile copies of this Agreement bearing facsimile signatures are exchanged between the parties hereto, such copies shall in all respects have the same weight, force and legal effect and shall be fully as valid, binding, and enforceable as if such signed facsimile copies were original documents bearing original signature.

6.        THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED, INTERPRETED AND ENFORCED ACCORDING TO, THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO PRINCIPLES OF CONFLICT OF LAWS PROVISIONS THEREOF. ANY ACTION BROUGHT CONCERNING THE TRANSACTIONS CONTEMPLATED BY THIS AGREEMENT SHALL BE BROUGHT ONLY IN THE STATE COURTS OF NEW YORK OR IN THE FEDERAL COURTS LOCATED IN THE STATE OF NEW YORK. The prevailing party shall be entitled to recover from the other party its reasonable attorneys’ fees and costs. Wherever possible each provision of this Agreement shall be interpreted in such manner as to be effective and valid under applicable law, but if any provision of this Agreement shall be prohibited by or invalid under such law, such provision shall be ineffective to the extent of such prohibition or invalidity, without invalidating the remainder of such provision or the remaining provisions of this Agreement.

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IN WITNESS WHEREOF, the undersigned have executed this Royalty Assignment Termination Agreement as of the date first above written.