Prospectus Supplement Filed pursuant to Rule 424(b)(3)

Registration No. 333-138257

PROSPECTUS SUPPLEMENT NO. 8

DATED JUNE 14, 2007

(To Prospectus Dated November 17, 2006)

BIOVEST INTERNATIONAL, INC.

18,000,000 Shares of Common Stock

This prospectus supplement supplements information contained in, and should be read in conjunction with, that certain Prospectus, dated November 17, 2006, of Biovest International, Inc. (the “Company”) as supplemented by Supplement No. 7 thereto dated May 15, 2007, Supplement No. 6 thereto dated April 19, 2007, Supplement No. 5 thereto dated March 28, 2007, Supplement No. 4 thereto dated February 14, 2007, Supplement No. 3 thereto dated January 19, 2007, Supplement No. 2 thereto dated December 29, 2006 and Supplement No. 1 thereto dated December 14, 2006. This prospectus supplement is not complete without, and may not be delivered or used except in connection with, the original Prospectus and Supplement Nos. 1, 2, 3, 4, 5, 6 and 7 thereto. The Prospectus relates to the public sale, from time to time, of up to 18,000,000 shares of our common stock by the selling shareholders identified in the Prospectus.

The information attached to this prospectus supplement modifies and supersedes, in part, the information in the Prospectus, as supplemented. Any information that is modified or superseded in the Prospectus shall not be deemed to constitute a part of the Prospectus, except as modified or superseded by this prospectus supplement or Prospectus Supplement Nos. 1, 2, 3, 4, 5, 6 and 7.

This prospectus supplement includes the attached Form 8-K as filed by us with the Securities and Exchange Commission on June 13, 2007.

We may amend or supplement the Prospectus from time to time by filing amendments or supplements as required. You should read the entire Prospectus and any amendments or supplements carefully before you make an investment decision.

The Securities and Exchange Commission and state securities regulators have not approved or disapproved these securities or determined if this Prospectus Supplement (or the original Prospectus dated November 17, 2006, as previously supplemented) is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus supplement is June 14, 2007.

U.S. SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Filed pursuant to Section 13 or 15(d)

Of the Securities Exchange Act of 1934

Date of report (Date of earliest event reported): June 8, 2007

BIOVEST INTERNATIONAL, INC.

(Exact Name of Registrant as Specified in Its Charter)

Delaware

(State or Other Jurisdiction of Incorporation)

377 Plantation Street

Worcester MA 01605

(Address of Principal Executive Office) (Zip Code)

508-793-0001

(Registrant’s Telephone Number, Including Area Code)

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2 below):

The following information is being furnished under Item 7.01 of Form 8-K:

a. Press release, dated June 5, 2007, by Biovest International, Inc. announcing the Company’s decision to apply for accelerated conditional approval for commercial sale of its BiovaxID anti-cancer vaccine. A copy of this press release is attached as Exhibit 99.1 to this Form 8-K;

b. Press release, dated June 12, 2007, by Biovest International, Inc. announcing entry into a Non-Exclusive Distribution Agreement with VWR International, Inc. for marketing and distribution of Biovest’s AutovaxID device. A copy of this press release is attached as Exhibit 99.2 to this Form 8-K;

c. Press Release dated June 13, 2007 by Biovest International, Inc. announcing that an interim analysis of data from the Company’s ongoing Phase 3 Clinical Trial of its anti-cancer vaccine, BiovaxID, will be conducted at the request of the independent Data Monitoring Committee. A copy of this press release is attached as Exhibit 99.3 to this Form 8-K.

On June 8, 2007 Biovest entered into a Non-Exclusive Distribution Agreement with VWR International, Inc. (“VWR”) to market and distribute its breakthrough AutovaxID™ automated cell culture device in North America. VWR plans to begin its sales and marketing activities in July 2007. The initial term of this Distribution Agreement is 24 months, and, unless earlier terminated by either party at the expiration of the then current term upon not less than 90 days’ prior notice, shall thereafter renew automatically for additional and successive terms of 12 months each.

For further detail as to this Distribution Agreement, please refer to the terms of the agreement which is attached as Exhibit 10.1 of this filing.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, hereunto duly authorized.

EXHIBIT INDEX

Exhibit 10.1

NON-EXCLUSIVE DISTRIBUTION AGREEMENT

THIS NON-EXCLUSIVE DISTRIBUTION AGREEMENT (this “Agreement”) is entered into as of this 1st day of June, 2007 (the “Effective Date”) by and between AutovaxID, Inc., a Florida corporation with its principal offices located at 1701 Macklind Avenue, St. Louis, MO 63110(“SUPPLIER”), and VWR INTERNATIONAL, INC., a Delaware corporation with its principal offices located at 1310 Goshen Parkway, West Chester, Pennsylvania 19380 (“DISTRIBUTOR”).

Intending to be legally bound, the parties hereto agree as follows:

The products covered by this Agreement are those products and accessories set forth in the attached Addendum A, together with the parts and components necessary for the repair and replacement thereof, and all modifications, improvements, developments, upgrades and replacements pertaining thereto (collectively, the “Products”). Addendum A shall be amended automatically from time to time without any further act of the parties to delete any Products the sale of which has been generally discontinued by SUPPLIER. Products may also be added to this Agreement pursuant to Section 1(b).

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The initial term of this Agreement shall begin on the date set forth in the first paragraph of this Agreement and shall continue for a term of 24 months, and, unless earlier terminated as set forth in Section 12 or by either party at the expiration of the then current term upon not less than 90 days’ prior notice, shall thereafter renew automatically for additional and successive terms of 12 months each.

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DISTRIBUTOR shall:

SUPPLIER shall:

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SUPPLIER shall: (1) prosecute diligently each application for United States and Canadian patent which is now or hereafter pending covering any of the Products and on issuance diligently prosecute each infringer thereof; and (2) repurchase from DISTRIBUTOR, at a price equal to the full purchase price paid by DISTRIBUTOR, any Products in DISTRIBUTOR’s inventory which DISTRIBUTOR reasonably believes it should not or cannot sell, based on an opinion of DISTRIBUTOR’s counsel that future sales by DISTRIBUTOR may result in a claim of patent, trade name, trade dress, trademark, service mark or copyright infringement, or violation of any other proprietary right, or because of a decision, whether interlocutory or final, rendered in an action alleging any such infringement or violation.

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SUPPLIER hereby grants to DISTRIBUTOR a royalty-free, irrevocable (during the term of this Agreement) and paid-up right and license to use SUPPLIER’s manuals, logos, copyrighted information, brand names, trademarks and trade names on, and in the promotion, marketing, sale and distribution of, the Products during the term of this Agreement within the Territory, it being expressly understood that DISTRIBUTOR shall discontinue, in a commercially reasonable time, the use thereof upon depletion of DISTRIBUTOR’s inventory of the Products following any expiration or termination of this Agreement. SUPPLIER shall use reasonable commercial efforts to register such brand names, trademarks, trade names and logos where reasonably necessary or useful to the successful distribution of the Products.

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Each Indemnified Party shall notify the party responsible for providing indemnification (as the case may be, the “Indemnifying Party”) of any third party claim for which such Indemnified Party seeks indemnification under this Agreement; provided, that the failure to deliver such notice shall not affect the Indemnifying Party’s obligations under this Section 10 except to the extent that the Indemnifying Party is adversely affected thereby. The Indemnifying Party may, but is not obligated to, assume the defense of any claim to which this Section 10 relates or may relate, and may appoint legal counsel responsible for such defense; provided, that if the Indemnifying Party chooses to assume such defense (w) the Indemnifying Party agrees that the Indemnified Party shall be entitled to recover from the Indemnifying Party all Damages arising out of such third party claim, (x) any Indemnified Party may, at its own expense, select its own counsel to represent it, (y), the Indemnifying Party may not settle any such claim against an Indemnified Party without the prior written consent of such Indemnified Party, and (z) the Indemnifying Party shall keep the Indemnified Party promptly informed of all developments in the defense of the action. If the Indemnifying Party elects not to assume such defense, such Indemnified Party may elect to do so and the Indemnifying Party shall pay all costs and expenses of counsel selected by such Indemnified Party in connection with such defense. Any legal counsel appointed by the Indemnifying Party to defend such a claim shall be experienced in the type of litigation involved and shall be reasonably satisfactory to the Indemnified Party. The Indemnifying Party and each Indemnified Party shall cooperate fully in connection with all matters related to the defense of any such claim.

During the term of this Agreement, each party may have or may be provided access to the other party’s confidential information and materials (including, without limitation, technical information, marketing, sales, the terms and conditions of this Agreement and new product development information). All such information which, if in written or other tangible form, is clearly designated as “confidential” or, if disclosed orally, is designated as “confidential” in a written memorandum delivered by the party disclosing the confidential information (the “Disclosing Party”) to the party receiving the confidential information (the “Receiving Party”)

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promptly following such oral disclosure, shall be retained in confidence in accordance with the terms of this Agreement and any applicable separate nondisclosure agreement between SUPPLIER and DISTRIBUTOR. Further, the Receiving Party shall not (except as expressly authorized herein during the term of this Agreement), either during the term of this Agreement or for three years after its termination or expiration, use, publish or disclose or cause or permit anyone else to use, publish or disclose any such information unless (i) such information was known to the Receiving Party at the time of receipt thereof from the Disclosing Party as evidenced by written documentation, (ii) such information becomes publicly available through no fault of the Receiving Party, or (iii) such information was lawfully obtained by the Receiving Party from any third party without violation of this Agreement. Nothing in this Section shall prevent a Receiving Party from disclosing confidential information of the Disclosing Party pursuant to a request of any court, government or governmental agency or as required by applicable Law; provided, however, that the Receiving Party shall give the Disclosing Party prompt notice of the required disclosure, and shall provide the Disclosing Party with reasonable assistance to the extent the Disclosing Party seeks a protective order or other means to preserve the confidentiality of the information required to be disclosed.

Upon termination or expiration of this Agreement, each party shall either return or destroy all copies of any confidential information of the other party described in Section 11(a) in such first party’s possession or control, and certify in writing that all copies of such information have been returned or destroyed.

Becomes insolvent, bankrupt or shall generally fail to pay its debts as such debts become due; admits in writing its inability to pay its debts; has a receiver or trustee or other similar official appointed by any court, governmental or public authority or agency having jurisdiction for it or its property; makes an assignment for the benefit of its creditors; has commenced by, for or against it any proceedings under any Law related to bankruptcy, insolvency or the reorganization or the release of debtors; or becomes liquidated or dissolved.

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Is affected by a force majeure event which continues for more than six (6) consecutive months.

Defaults or is in breach of any material term or provision of this Agreement, and fails (i) within ten days following delivery by the terminating party of a notice specifying such default or breach, to notify the terminating party that such default or breach has been cured or shall be cured within 30 days following delivery of such notice, or (ii) within 30 days following delivery by the terminating party of such notice, to remedy such default or breach to the terminating party’s reasonable satisfaction.

DISTRIBUTOR may terminate this Agreement at any time with or without cause and without liability, upon 180 days written notice to SUPPLIER.

For a period of 60 days following the effective date of termination of this Agreement by DISTRIBUTOR, SUPPLIER shall continue to honor DISTRIBUTOR’s orders for Products, and DISTRIBUTOR shall pay for the Products on the terms and conditions of this Agreement.

Within 60 days after the effective date of termination or expiration of this Agreement for any reason, upon written request from DISTRIBUTOR, SUPPLIER shall repurchase DISTRIBUTOR’s inventory of the Products, at the full price paid by DISTRIBUTOR therefor.

The provisions of Sections, 5(b), 6(a)(4), 6(e), 6(g), 6(j), 6(k), 6(n), 6(o), 8, 9, 10, 11 and this 13 shall remain in full force and effect following the termination or expiration of this Agreement.

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All notices required by this Agreement shall be in writing, and shall be effective on receipt if delivered personally, on the first business day following the date of mailing if sent by a nationally recognized courier guaranteeing next day delivery, or on the third business day following the date of mailing if sent by certified mail, postage prepaid, addressed as follows (or to such other addresses as may be designated by similar notice from time to time delivered to the other party):

If to SUPPLIER, to:

AutovaxID Inc.

1701 Macklind Avenue

St. Louis, MO 63110

Attention: Steven Arikian, M.D. CEO

With a copy to:

324 S. Hyde Park Avenue, Suite 350

Tampa FL 33606

Attention: Legal Department

If to DISTRIBUTOR, to:

VWR International, Inc.

1310 Goshen Parkway

West Chester, PA 19380

Attention: General Counsel

If the Products to be furnished by SUPPLIER are to be used in the performance of a U.S. government contract or subcontract, those clauses of the applicable U.S. Government procurement regulation which are required by Federal Statute to be included in U.S. Government subcontracts shall be incorporated herein by reference including, without limitation, the Fair Labor Standards Act of 1938, as amended.

This Agreement and the attached Addendum, as well as DISTRIBUTOR’s most recently published routing guides and Global Logistics Delivery Requirements constitute the entire agreement between the parties with respect to the subject matter hereof and supersede all prior agreements

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and understandings, oral and written among the parties with respect to the subject matter hereof. No amendment, modification or waiver of the terms of this Agreement shall be binding on either party unless reduced to writing and signed by an authorized officer of the party to be bound and, in the case of a waiver, shall be effective only in the specific instance, and for the specific purpose for which given, and shall not be construed as a waiver of any subsequent breach. The failure of either party to enforce at any time or for any period of time any of the provisions of this Agreement shall not be construed as a waiver of such provisions or of the right of such party thereafter to enforce each and every such provision.

The captions in this Agreement have been inserted for convenience of reference only and do not constitute a part of, and shall not be considered in construing, this Agreement. If any portion of this Agreement is held by a court of competent jurisdiction to be invalid for any reason, the remainder of this Agreement shall not be deemed invalid but shall remain in full force and effect. No course of dealing, usage of trade or course of performance shall supplement, explain or amend any term, condition or instruction of this Agreement, or any shipment of Products hereunder.

This Agreement is made pursuant to, and shall be construed and enforced exclusively in accordance with, the internal laws of the Commonwealth of Pennsylvania (and United States federal law, to the extent applicable), without giving effect to otherwise applicable principles of conflicts of law. The United Nations Convention on Contracts for the International Sales of Goods expressly shall not apply.

This Agreement shall be binding upon and inure to the benefit of the parties hereto and their respective successors and permitted assigns and designees. Neither party may transfer, assign or delegate its rights or obligations under this Agreement or any portion thereof without the prior written consent of the other party, except for any transfer, assignment or delegation, in whole or in part, to its respective parent, subsidiaries or other affiliates, or to a successor entity.

Any Affiliate of DISTRIBUTOR may participate in this Agreement to the same extent as DISTRIBUTOR, and, without limiting the generality of the foregoing, shall have the right to purchase Products directly from

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SUPPLIER pursuant to Section 5 and to promote, market, sell and distribute Products pursuant to Section 2. For the purposes of this Agreement an Affiliate of DISTRIBUTOR shall mean any entity which is directly or indirectly controlled by DISTRIBUTOR; DISTRIBUTOR shall be deemed to control another entity if DISTRIBUTOR has the power to direct or cause the direction of the management and policies of such entity, whether through the ownership of voting equity, by contract or otherwise, including, but not limited to, ownership of at least thirty percent (30%) of the outstanding voting equity of such entity.

Neither party, its agents or employees shall, under any circumstances, be considered to be an agent, partner, joint venturer or representative of the other party, or anything other than an independent contractor for all purposes of this Agreement, and except as may be authorized specifically in writing, neither party has express or implied authority to bind the other in any manner whatsoever by virtue of this Agreement.

For convenience of the parties, this Agreement may be executed in one or more counterparts, each of which shall be deemed an original for all purposes. A facsimile or photocopied signature shall be deemed to be the functional equivalent of an original for all purposes.

If any term or provision of this Agreement, or the application thereof to any person or circumstance, shall, to any extent, be invalid or unenforceable, the remainder of this Agreement, or application to other persons or circumstances, shall not be affected thereby, and each term and provision of this Agreement shall be enforced to the fullest extent permitted by Law.

The parties hereto agree that irreparable harm would occur in the event that any of the agreements and provisions of Section 2 (Grant of Non-Exclusive Distribution) or Section 11 (Confidentiality) were not performed fully by the parties hereto in accordance with their specific terms or conditions or were otherwise breached, and that money damages are an inadequate remedy for breach of such Sections because of the difficulty of ascertaining and quantifying the amount of damage that will be suffered by the parties hereto in the event that those Sections are not performed in accordance with their terms or conditions or are otherwise breached. It is accordingly hereby agreed that the parties hereto shall be entitled to an

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injunction or injunctions to restrain, enjoin and prevent breaches of Section 2 (Grant of Non-Exclusive Distribution) and Section 11 (Confidentiality) by the other parties and to enforce specifically such terms and provisions provided in such Sections, such remedy being in addition to and not in lieu of, any other rights and remedies to which the other parties are entitled to at law or in equity.

Without the prior written consent of the other party, neither party shall disclose to any third person the existence or purpose of this Agreement, its terms or conditions, or the fact that discussions are taking place and that Confidential Information is being shared, except as may be required by Law or court order and then only after first notifying in writing the other party of such required disclosure.

[Signature Page Follows]

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IN WITNESS WHEREOF, and intending to be legally bound hereby, the parties have caused this Agreement to be executed and delivered by their duly authorized officers as of the date first above written.

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Addendum A

Product Listing

AutovaxID™ Products and Services

US Ordering Information, 2007

5/16/2007

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Addendum B

VWR Marketing Plan

1. Differentiated Supplier Status: As a differentiated supplier at VWR, Biovest will have the highest possible profile within our organization. Our executive management and sales team is given a higher focus and visibility on the sale of Biovest products, than other non-differentiated suppliers. The number of suppliers in this top tier is limited by VWR.

2. VWR Life Science: The Biovest product range will be part of our “Preferred Supplier” program within the VWR Life Science Category. This program is supported by 31 Life Science Sales Specialists in North America, 3 Sales Directors, 1 Category Manager and 1 Marketing Manager. The Life Science sales team has a higher compensation rate on our “Preferred Suppliers”.

3. Web Site: Preferred placement of Biovest products with supporting literature, application notes and technical information on VWR.com. Biovest products will be given a priority “weighting” during product searches, so that the Biovest products come up first in all related product searches.

4. Publications: VWR will promote AutovaxID products in their publications described in a presentation sent to Biovest on May 16, 2007

5. Sales Conversion Programs: Participation in sales conversion programs at VWR target accounts including Pharma, Biotech, Academic and Medical Research customers.

6. Priority Training and Meeting Participation: Biovest will be invited to participate in all VWR sales meeting (National, regional and local) as well as having the opportunity to provide training to the 450 VWR sales associates and 31 Life Science Specialists in North America.

Exhibit 99.1

Biovest to File for Accelerated Conditional Approval of BiovaxID

Findings Based on 14 Years of Clinical Experience, 9 Years of Median Follow-Up Data and Ongoing Phase 3 Results: Clinical Studies Show BiovaxID Has Favorable Risk-Benefit Ratio as a Complement to Existing Standards of Care

WORCESTER, MA—June 5, 2007—Biovest International, Inc. (OTCBB:BVTI), a majority-owned subsidiary of Accentia Biopharmaceuticals, Inc. (NASDAQ:ABPI), will file and seek conditional approval of its therapeutic anti-cancer vaccine, BiovaxID™, for the indication of follicular Non-Hodgkin’s Lymphoma (NHL). If conditionally approved by the target date of mid-June 2008, Biovest would anticipate commencing commercial sales and marketing by early 2009. Conditional Approval would require the company to complete the ongoing Phase 3 study as a condition to continued marketing of BiovaxID. Biovest intends to file separate applications with the U.S. Food and Drug Administration (FDA) and its European counterpart, the European Medicines Agency (EMEA).

On June 2, 2007, the independent Data Monitoring Committee (DMC) met to review all data for the BiovaxID Phase 3 pivotal efficacy study. Following the meeting with the DMC, Biovest notified the DMC of its intent to seek Conditional Approval in the U.S. and Europe. Biovest plans to seek conditional approval based on the pre-clinical and clinical Phase 2 and ongoing Phase 3 data supporting its highly favorable risk-benefit profile, driven in large part by its exemplary safety record, and evidence of efficacy to date in the treatment of follicular lymphoma, a life-threatening, serious and debilitating condition.

Dr. Larry Kwak, Chairman of the Department of Lymphoma and Myeloma at the MD Anderson Cancer Center, the lead site for the BiovaxID Phase 3 clinical trials, commented, “I fully support Biovest’s strategy to seek conditional approval because patients with NHL continue to deteriorate over time despite substantial recent advances in its treatment. There is a tremendous need for access to BiovaxID, which holds the potential to cure many patients.”

“As there are currently no cures for this fatal disease, our planned discussions with the FDA and EMEA to achieve conditional approval of BiovaxID are critical steps in our effort to make BiovaxID broadly available to non-Hodgkin’s Lymphoma patients worldwide,” said Dr. Steven Arikian, Chairman and Chief Executive Officer of Biovest.

“While currently available treatments are effective at inducing remissions in patients with follicular lymphoma, the disease inevitably returns,” Arikian stated. “Independently-confirmed evidence demonstrates that BiovaxID, used as a complement to existing treatments such as PACE or CHOP-R, stimulates the immune system to delay and even eliminate relapses. State-of-the-art treatments within the BiovaxID clinical trial, especially CHOP-R, open our study to many more participants, allowing Biovest to accelerate and complete study accrual.”

Dr. Arikian continued: “While we cannot be certain of the vaccine’s effect before analyzing the unblinded data, based on the blinded information and interim Kaplan Meier Curves which we have been provided to date, the vaccine appears to be working as expected in our pivotal Phase 3 efficacy trial. This conclusion is drawn based upon the notably higher relapse rate observed in

the population prior to the time of vaccination, and the very obvious flattening of the survival curve in the later years of follow-up. We are confident our Phase 3 final data will be consistent with the previous Phase 2 results.”

In lymphoma, each cancerous B-cell produces a unique immunoglobin protein and expresses this antigen on the cell surface. In the mid-1980s, researchers at Stanford University hypothesized that the unique antigen (the idiotype) present on each cancer B-cell in the body could be used to develop a vaccine capable of stimulating the immune system to destroy those B-cells but spare the non-cancerous cells.

BiovaxID is designed to stimulate a patient’s immune system to recognize and destroy cancerous B-cells that may remain in the body or may arise after the patient has been treated with chemotherapy. Unlike many other approaches to treating NHL, BiovaxID is designed to kill only cancerous B-cells, and does not result in making patients immunocompromised as with monoclonal antibodies such as Rituxan.

In the Phase 2 clinical study conducted at the NCI, 20 patients in continuous first complete remission (CR) after chemotherapy treatment were treated with a series of 5 monthly vaccinations of BiovaxID conjugated to KLH and administered with local GM-CSF. After vaccination, 95% of patients showed autologous tumor-specific cellular T-cell responses and 75% of patients showed humoral antibody responses. With a median follow-up of 9.2 years, 45% of patients remained in continuous first CR and the median Disease Free Survival (DFS) for the cohort was 96.5 months, 8.0 years (American Society of Hematology, December 2005, Abstract #2441). Furthermore, 73% of evaluable patients were converted into molecular remission (bcl-2 negative) after the administration of BiovaxID and, thus, cleared the blood of residual cancer cells (American Society of Clinical Oncology, June 2006). At 9.2 years of follow-up, 95% of the patients remained alive, comparing favorably to historical controls where an approximate 50% survival would be expected at that time.

Independent studies done on BiovaxID formulations at Stanford University by Dr. Ron Levy and colleagues, who pioneered this active immunotherapeutic strategy, and the University of Navarra by former members of the NCI team that refined this approach provide additional evidence for the safety and clinical benefit of this anticancer immunotherapeutic. In the Navarra study published in 2006, for example, the clinical benefit was significant at the P=0.001 level.

The BiovaxID study is being conducted at 14 oncology, academic and private practice centers within the United States and 19 centers in Russia. In addition, 8 centers have been initiated in the Ukraine as well.

About Conditional Approval under Subpart E (21CFR 601, Subpart E, Accelerated Approval of Biological Products for Serious or Life-Threatening Illnesses)

FDA may accelerate approval of certain new biological products for serious or life-threatening illnesses, with provisions for any necessary continued study of the drugs’ clinical benefits after approval or with restrictions on use, if necessary. Subpart E is intended to provide expedited marketing of drugs for patients suffering from such illnesses when the drugs provide meaningful therapeutic benefit compared to existing treatments. Accelerated approval will be considered in two situations: (1) When approval can be reliably based on evidence from adequate and well-controlled studies of the drug’s effect on a surrogate endpoint that reasonably suggests clinical benefit or on evidence of the drug’s effect on a clinical endpoint other than survival or irreversible morbidity, pending completion

of studies to establish and define the degree of clinical benefits to patients; and (2) when FDA determines that a drug, effective for the treatment of a disease, can be used safely only if distribution or use is modified or restricted. Drugs or biological products approved under these procedures must have met the requisite standards for safety and effectiveness under the Federal Food, Drug, and Cosmetic Act (the act) or the Public Health Service Act (the PHS Act) and, thus, will have full approval for marketing.

About Biovest International, Inc.

Biovest International, Inc., is a pioneer in the development of advanced individualized immunotherapies for life-threatening cancers of the blood system. Biovest is a majority-owned subsidiary of Accentia Biopharmaceuticals, Inc., (NASDAQ:ABPI ) with its remaining shares publicly traded. Biovest has a foundation in the manufacture of biologics for research and clinical trials. In addition, Biovest develops, manufactures and markets patented cell culture systems, including the innovative AutovaxID(TM), which is being marketed as an automated vaccine manufacturing instrument and for production of cell-based materials and therapeutics. Biovest is currently conducting a pivotal Phase 3 clinical trial for BiovaxID which is a patient-specific anti-cancer vaccine focusing on the treatment of follicular non-Hodgkin’s lymphoma. BiovaxID has been granted Fast Track status by the FDA. For further information, visit the Company Web site at www.biovest.com.

About Accentia Biopharmaceuticals, Inc.

Accentia Biopharmaceuticals, Inc. and its subsidiaries (collectively referred to as the “Company” or “Accentia”) is a vertically integrated biopharmaceutical company focused on the development and commercialization of drug candidates that are in late-stage clinical development and typically are based on active pharmaceutical ingredients that have been previously approved by the FDA for other indications. Usually these drug candidates can access the accelerated 505(b)(2) regulatory approval pathway, which is generally less time-consuming and less expensive than the typical 505(b)(1) pathway that must be used for new chemical entities. The Company’s lead product candidate is SinuNase(TM), a novel application and formulation of a known therapeutic to treat chronic rhinosinusitis. SinuNase has been granted Fast Track status by the FDA and it is currently in a pivotal Phase 3 clinical trial. During this fiscal year, the Company also plans to file an Investigative New Drug (IND) for a pivotal Phase 3 clinical trial of Revimmune, to treat numerous autoimmune diseases with an initial indication targeting refractory relapsing-remitting Multiple Sclerosis. Revimmune is based on pulsed, ultra-high dosing of a well-known chemotherapeutic agent under a risk management program. Additionally, through an investment strategy, the Company has acquired the majority ownership interest in Biovest International, Inc. (“Biovest”), (BVTI.OB) and a royalty interest in Biovest’s lead drug candidate, BiovaxID(TM) and any other biologic products developed by Biovest. Biovest is currently conducting a pivotal Phase 3 clinical trial for BiovaxID which is a patient-specific anti-cancer vaccine focusing on the treatment of follicular non-Hodgkin’s lymphoma. BiovaxID has been granted Fast Track status by the FDA. In addition to these product candidates, the Company has a specialty pharmaceutical business which markets products focused on respiratory disease and an analytical consulting business that serves customers in the biopharmaceutical industry. For further information, visit the Company Web site at www.accentia.net.

Forward-Looking Statements

Statements in this release that are not strictly historical in nature constitute “forward-looking statements.” Such statements include, but are not limited to, statements about Revimmune(TM) SinuNase(TM), BiovaxID(TM), AutovaxID(TM), CRSFungal Profile(TM) and any other statements relating to products, product candidates, product development programs the FDA or clinical study process including the commencement, process or completion of clinical trials or the regulatory process. Such statements may include, without limitation, statements with respect to the Company’s plans, objectives, expectations and intentions and other statements identified by words such as “may,” “could,” “would,” “should,” “believes,” “expects,” “anticipates,” “estimates,” “intends,” “plans” or similar expressions. Such forward-looking statements involve known and unknown risks, uncertainties, and other factors that may cause the actual results of Accentia to be materially different from historical results or from any results expressed or implied by such forward-looking statements. These factors include, but are not limited to, risks and uncertainties related to the progress, timing, cost, and results of clinical trials and product development programs;

difficulties or delays in obtaining regulatory approval for product candidates; competition from other pharmaceutical or biotechnology companies; and the additional risks discussed in filings with the Securities and Exchange Commission. All forward-looking statements are qualified in their entirety by this cautionary statement, and Accentia undertakes no obligation to revise or update this news release to reflect events or circumstances after the date hereof.

Contact:

Biovest International, Inc., New York, NY

Steven Arikian, MD

Chairman and Chief Executive Officer

Tel 212 686 4100 ext 8640

sarikian@biovest.com

Accentia Biopharmaceuticals, Inc., Tampa, FL

Susan Bonitz, Ph.D.; 813-864-2554-Extension 277

sbonitz@accentia.net

Investors:

The Investor Relations Group, New York

Adam S. Holdsworth, 212-825-3210

aholdsworth@investorrelationsgroup.com

or

Media:

Janet Vasquez, 212-825-3210

jvasqyez@investorrelationsgroup.com

Exhibit 99.2

Biovest and VWR Enter into Marketing and Distribution Agreement for AutovaxID

Dedicated AutovaxID Manufacturing Facility in St. Louis to be Operational September 2007

Worcester, MA—(BUSINESS WIRE)—June. 12, 2007—Biovest International, Inc. (OTCBB:BVTI) a majority owned subsidiary of Accentia Biopharmaceuticals Inc (NASDAQ: ABPI) has entered into a distribution agreement with VWR International, Inc., to distribute its breakthrough AutovaxID™ automated cell culture device in North America. The company believes that this agreement will provide AutovaxID with a preferred position in the market and allow the AutovaxID to achieve rapid market penetration. VWR plans to begin its sales and marketing activities of this product line in July 2007.

To support the anticipated demand for its AutovaxID instruments, Biovest also announced today that its manufacturing facility dedicated to producing AutovaxID units in St. Louis, MO will be operational in September 2007. The new facility consists of 17,000 square feet customized for the manufacture of this new product.

Under the terms of the VWR agreement, Biovest and VWR will service North American customers in an integrated manner. In addition to increasing AutovaxID’s presence in the North American market with broader sales representation and customer relationships, VWR will be working with Biovest to offer additional products and services to its cell culture customers. Biovest will continue to support North American customers with direct sales representation and field applications support personnel as well as provide technical support and instrument service from its U.S. offices.

Dr. Steve Arikian, Chairman and Chief Executive Officer of Biovest commented, “The AutovaxID is a major advance in cell culture for production of complex biologics, especially in personalized medicine. This agreement with VWR greatly enhances our access to North American customers through their team of Life Science Specialists and high visibility in their marketing program.”

The AutovaxID is a fully automated, reusable instrument that employs a fully disposable, closed-system cell-growth chamber incorporating a hollow-fiber cell-growth cartridge. This unique bioreactor replaces conventional stainless steel, glass, and plastic cell-growth chambers that require up to ten times as much laboratory space. Because it is fully enclosed and automated, AutovaxID requires almost no supervision and is less expensive to operate. AutovaxID is a technologically-advanced commercial cell culture system for personalized medicine applications, enabling scalable, cost-effective production of cells or cell-derived products, including monoclonal antibodies.

Biovest plans to utilize the AutovaxID technology to streamline commercial manufacture of its proprietary anti-cancer vaccine, BiovaxID™, which is currently in a pivotal Phase III Clinical Trial and under Fast Track status with the US FDA. On June 4, 2007 Biovest announced that it intends to submit to global regulatory authorities for accelerated conditional approval of BiovaxID.

According to Brian Kerslake, VWR Vice President of Life Science. “Our agreement enhances VWR’s supplier network by extending AutovaxID’s high quality and innovative automated cell culture instruments to our customers. Our relationship will continue to strengthen VWR’s ability to provide our customers with superior solutions and technology.”

About VWR International, Inc.

VWR International is a leader in the global research laboratory industry with worldwide sales in excess of $3 billion US dollars. VWR’s business is highly diversified across products and services, geographic regions and customer segments. The company offers products from a wide range of manufacturers, to a large number of customers primarily in North America, Europe and other locations. VWR’s principal customers are major pharmaceutical, biotechnology, chemical, technology, clinical, food processing and consumer product companies, universities and research institutes, governmental agencies, environmental testing organizations, and primary and secondary schools. VWR distributes a diversified product mix, including chemicals, glassware and plasticware, equipment and

instruments, furniture, protective apparel, production and safety products, and other life science and laboratory products and supplies. VWR supports its customers by providing storeroom management, product procurement, supply chain systems integration, technical services and laboratory bench top delivery. VWR maintains operations in over 20 countries and employs over 6,000 people worldwide. VWR International is headquartered in West Chester, Pennsylvania. VWR-G

For more information on VWR International, phone 1-800-932-5000, visit www.vwr.com, or write, VWR International, Inc., 1310 Goshen Parkway, P.O. Box 2656, West Chester, PA 19380-0906.

About Biovest International, Inc.

Biovest International, Inc., is a pioneer in the development of advanced individualized immunotherapies for life-threatening cancers of the blood system. Biovest is a majority-owned subsidiary of Accentia Biopharmaceuticals, Inc., (NASDAQ:ABPI ) with its remaining shares publicly traded. Biovest has a foundation in the manufacture of biologics for research and clinical trials. In addition, Biovest develops, manufactures and markets patented cell culture systems, including the innovative AutovaxID(TM), which is being marketed as an automated vaccine manufacturing instrument and for production of cell-based materials and therapeutics. Biovest is currently conducting a pivotal Phase 3 clinical trial for BiovaxID which is a patient-specific anti-cancer vaccine focusing on the treatment of follicular non-Hodgkin’s lymphoma. BiovaxID has been granted Fast Track status by the FDA. For further information, visit the Company Web site at www.biovest.com.

About Accentia Biopharmaceuticals, Inc.

Accentia Biopharmaceuticals, Inc. and its subsidiaries (collectively referred to as the “Company” or “Accentia”) is a vertically integrated biopharmaceutical company focused on the development and commercialization of drug candidates that are in late-stage clinical development and typically are based on active pharmaceutical ingredients that have been previously approved by the FDA for other indications. Usually these drug candidates can access the accelerated 505(b)(2) regulatory approval pathway, which is generally less time-consuming and less expensive than the typical 505(b)(1) pathway that must be used for new chemical entities. The Company’s lead product candidate is SinuNase(TM), a novel application and formulation of a known therapeutic to treat chronic rhinosinusitis. SinuNase has been granted Fast Track status by the FDA and it is currently in a pivotal Phase 3 clinical trial. During this fiscal year, the Company also plans to file an Investigative New Drug (IND) for a pivotal Phase 3 clinical trial of Revimmune, to treat numerous autoimmune diseases with an initial indication targeting refractory relapsing-remitting Multiple Sclerosis. Revimmune is based on pulsed, ultra-high dosing of a well-known chemotherapeutic agent under a risk management program. Additionally, through an investment strategy, the Company has acquired the majority ownership interest in Biovest International, Inc. (“Biovest”), (BVTI.OB) and a royalty interest in Biovest’s lead drug candidate, BiovaxID(TM) and any other biologic products developed by Biovest. Biovest is currently conducting a pivotal Phase 3 clinical trial for BiovaxID which is a patient-specific anti-cancer vaccine focusing on the treatment of follicular non-Hodgkin’s lymphoma. BiovaxID has been granted Fast Track status by the FDA. In addition to these product candidates, the Company has a specialty pharmaceutical business which markets products focused on respiratory disease and an analytical consulting business that serves customers in the biopharmaceutical industry. For further information, visit the Company Web site at www.accentia.net.

Forward-Looking Statements

Statements in this release that are not strictly historical in nature constitute “forward-looking statements.” Such statements include, but are not limited to, statements about Revimmune(TM) SinuNase(TM), BiovaxID(TM), AutovaxID(TM), CRSFungal Profile(TM) and any other statements relating to products, product candidates, product development programs the FDA or clinical study process including the commencement, process or completion of clinical trials or the regulatory process. Such statements may include, without limitation, statements with respect to the Company’s plans, objectives, expectations and intentions and other statements identified by words such as “may,” “could,” “would,” “should,” “believes,” “expects,” “anticipates,” “estimates,” “intends,” “plans” or similar expressions. Such forward-looking statements involve known and unknown risks, uncertainties, and other factors that may cause the actual results of Accentia to be materially different from historical results or from any results expressed or implied by such forward-looking statements. These factors include, but are not limited to, risks and uncertainties related to the progress, timing, cost, and

results of clinical trials and product development programs; difficulties or delays in obtaining regulatory approval for product candidates; competition from other pharmaceutical or biotechnology companies; and the additional risks discussed in filings with the Securities and Exchange Commission. All forward-looking statements are qualified in their entirety by this cautionary statement, and Accentia undertakes no obligation to revise or update this news release to reflect events or circumstances after the date hereof.

Contact:

Biovest International, Inc., New York, NY

Steven Arikian, MD

Chairman and Chief Executive Officer

Tel 212 686 4100 ext 8640

sarikian@biovest.com

Accentia Biopharmaceuticals, Inc., Tampa, FL

Susan Bonitz, Ph.D.; 813-864-2554-Extension 277

sbonitz@accentia.net

VWR International, Inc.

Brian Kerslake

Vice President, Life Science

610-429-2828

brian_Kerslake@vwr.com

Investors:

The Investor Relations Group, New York

Adam S. Holdsworth, 212-825-3210

or

Media:

Janet Vasquez, 212-825-3210

Exhibit 99.3

Interim Analysis of Anti-Cancer Vaccine, BiovaxID, to be Conducted

Independent Data Monitoring Committee Requests Data Lock and Report of Interim Analysis

BiovaxID Phase 3 Clinical Trial Has No Identifiable Safety Concerns

Worcester, MA—June 13, 2007 — Biovest International, Inc. (OTCBB: BVTI), a majority owned subsidiary of Accentia Biopharmaceuticals, Inc. (NASDAQ:ABPI) announces a milestone in its effort to gain accelerated conditional approval for BiovaxID™. The independent Data Monitoring Committee (DMC) has requested an interim analysis of all primary and secondary endpoints. The DMC is the independent committee that is responsible for safety and efficacy reviews of the BiovaxID Phase 3 Clinical Trial. Further, the DMC has requested data lock to occur in September 2007 to facilitate this interim analysis.

Additionally, the DMC has informed the Company that, after its review of unblinded data for the BiovaxID Phase 3 Clinical Trial, there are no identifiable safety concerns related to this therapy. The company believes that BiovaxID’s strong safety record will be supportive of its planned application for accelerated conditional approval of BiovaxID.

BiovaxID is an anti-cancer vaccine that is in pivotal Phase 3 Clinical Trial for the indication of non-Hodgkins lymphoma (NHL). BiovaxID is a personalized, patient specific vaccine designed to stimulate the patient’s own immune system to recognize and destroy cancerous B-cells that may remain in the body or may arise after the patient has been treated with chemotherapy. Unlike many other approaches to treating NHL, BiovaxID is designed to kill only cancerous B-cells. The BiovaxID Phase 3 clinical trial is being conducted at fourteen oncology centers within the United States and nineteen centers in Russia.

The Chairman of the DMC, Dr. Gerry Messerschmidt, MD, FACP, stated, “There are no identifiable safety concerns in the current BiovaxID Phase 3 pivotal Clinical Trial at this time in our data review. To facilitate Biovest’s regulatory agency discussions and petitions based on its announced decision to seek accelerated conditional approval of BiovaxID, the DMC has requested that the database be fully updated and appropriate analyses of all enrolled/randomized patients to-date be performed for “DMC-only” closed session review at the Committee’s next scheduled meeting in September 2007. At that time, the independent committee will explore possible mechanisms of unblinded data review with regulatory agencies.”

Dr Messerschmidt further stated, “The DMC recommends continuation of the Trial with the following changes: that the CHOP-R induction chemotherapy arm (the current Standard of Care) remain open and active; the PACE therapy arm of the study be discontinued, with protocol- defined follow-up of all current PACE patients enrolled.”

Applications for accelerated conditional approval of BiovaxID are planned to be submitted to both the Food and Drug Administration (FDA) and European Medicines Agency (EMEA) by mid-2008. The DMC has agreed to serve as a liaison between the Company and the FDA and the EMEA. If conditionally approved by the target date of mid-June 2008, BiovaxID would be commercially available in early 2009.

Dr. Steven Arikian, Chairman and CEO of Biovest, stated that “The Phase 2 efficacy and safety data, combined with the Phase 3 safety data, blinded disease progression data, and third-party published data, reinforce our confidence that this anti-cancer vaccine is effective and the risk-benefit of BiovaxID in defeating NHL will be proven. Our follow-up data, which was generated during the National Cancer Institute (“NCI”) Phase 2 Clinical Trial, is now 10 years mature and our initial Phase 3 Clinical Trial patients will be 7 years mature at the data lock scheduled for September of this year. We believe that our robust and lengthy follow-up data, which covers over 200 patients in the Phase 2 and Phase 3 Clinical Trials to date, will be helpful in supporting our application for accelerated conditional approval of BiovaxID. Pursuant to the DMC’s request, we plan to submit a comprehensive interim analysis to the DMC in September 2007.”

Dr. Arikian added that, “We are pleased with the independent confirmation of BiovaxID’s overall safety profile in its ongoing Phase 3 Clinical Trial. We are committed to getting BiovaxID to NHL patients as soon as possible. The support being offered by the DMC in upcoming discussions with the FDA and EMEA is of the utmost importance in achieving this goal.”

About Biovest International, Inc.

Biovest International, Inc., is a pioneer in the development of advanced individualized immunotherapies for life-threatening cancers of the blood system. Biovest is a majority-owned subsidiary of Accentia Biopharmaceuticals, Inc., (NASDAQ:ABPI ) with its remaining shares publicly traded. Biovest has a foundation in the manufacture of biologics for research and clinical trials. In addition, Biovest develops, manufactures and markets patented cell culture systems, including the innovative AutovaxID™, which is being marketed as an automated vaccine manufacturing instrument and for production of cell-based materials and therapeutics. Biovest is currently conducting a pivotal Phase 3 clinical trial for BiovaxID which is a patient-specific anti-cancer vaccine focusing on the treatment of follicular non-Hodgkin’s lymphoma. BiovaxID has been granted Fast Track status by the FDA. For further information, visit the Company Web site at www.biovest.com.

About Accentia Biopharmaceuticals, Inc.

Accentia Biopharmaceuticals, Inc. and its subsidiaries (collectively referred to as the “Company” or “Accentia”) is a vertically integrated biopharmaceutical company focused on the development and commercialization of drug candidates that are in late-stage clinical development and typically are based on active pharmaceutical ingredients that have been previously approved by the FDA for other indications. Usually these drug candidates can access the accelerated 505(b)(2) regulatory approval pathway, which is generally less time-consuming and less expensive than the typical 505(b)(1) pathway that must be used for new chemical entities. The Company’s lead product candidate is SinuNase(TM), a novel application and formulation of a known therapeutic to treat chronic rhinosinusitis. SinuNase has been granted Fast Track status by the FDA and it is currently in a pivotal Phase 3 clinical trial. During this fiscal year, the Company also plans to file an Investigative New Drug (IND) for a pivotal Phase 3 clinical trial of Revimmune, to treat numerous autoimmune diseases with an initial indication targeting refractory relapsing-remitting Multiple Sclerosis. Revimmune is based on pulsed, ultra-high dosing of a well-known chemotherapeutic agent under a risk management program. Additionally, through an investment strategy, the Company has

acquired the majority ownership interest in Biovest International, Inc. (“Biovest”), (BVTI.OB) and a royalty interest in Biovest’s lead drug candidate, BiovaxID™ and any other biologic products developed by Biovest. Biovest is currently conducting a pivotal Phase 3 clinical trial for BiovaxID which is a patient-specific anti-cancer vaccine focusing on the treatment of follicular non-Hodgkin’s lymphoma. BiovaxID has been granted Fast Track status by the FDA. In addition to these product candidates, the Company has a specialty pharmaceutical business which markets products focused on respiratory disease and an analytical consulting business that serves customers in the biopharmaceutical industry. For further information, visit the Company Web site at www.accentia.net.

Forward-Looking Statements

Statements in this release that are not strictly historical in nature constitute “forward-looking statements.” Such statements include, but are not limited to, statements about Revimmune(TM) SinuNase(TM), BiovaxID(TM), AutovaxID(TM), CRSFungal Profile(TM) and any other statements relating to products, product candidates, product development programs the FDA or clinical study process including the commencement, process or completion of clinical trials or the regulatory process. Such statements may include, without limitation, statements with respect to the Company’s plans, objectives, expectations and intentions and other statements identified by words such as “may,” “could,” “would,” “should,” “believes,” “expects,” “anticipates,” “estimates,” “intends,” “plans” or similar expressions. Such forward-looking statements involve known and unknown risks, uncertainties, and other factors that may cause the actual results of Accentia to be materially different from historical results or from any results expressed or implied by such forward-looking statements. These factors include, but are not limited to, risks and uncertainties related to the progress, timing, cost, and results of clinical trials and product development programs; difficulties or delays in obtaining regulatory approval for product candidates; competition from other pharmaceutical or biotechnology companies; and the additional risks discussed in filings with the Securities and Exchange Commission. All forward-looking statements are qualified in their entirety by this cautionary statement, and Accentia undertakes no obligation to revise or update this news release to reflect events or circumstances after the date hereof.

Contact:

Biovest International, Inc., New York, NY

Steven Arikian, MD

Chairman and Chief Executive Officer

Tel 212 686 4100 ext 8640

sarikian@biovest.com

Accentia Biopharmaceuticals, Inc., Tampa, FL

Susan Bonitz, Ph.D.; 813-864-2554-Extension 277

sbonitz@accentia.net

Investors:

The Investor Relations Group, New York

Adam S. Holdsworth, 212-825-3210

or

Media:

Janet Vasquez, 212-825-3210