Biovest International's Phase 3 Therapy for Follicular Lymphoma Receives Independent Support From Newly Published Phase 2 Trial Data.

Study using hybridoma-derived vaccine shows first-ever improvement in disease-free-survival following prior relapse for this disease

WORCESTER, Mass. -- Biovest International, Inc. (OTCBB: BVTI) announced that a publication in the September 20th issue of the Journal of the National Cancer Institute provides support for its ongoing phase 3 trial of BiovaxID, an autologous immunotherapy for follicular non-Hodgkin's Lymphoma. The publication, entitled "Clinical Benefit Associated With Idiotypic Vaccination of Patients With Follicular Lymphoma" by Susana Inoges, et al (Journal of the National Cancer Institute, Vol. 98, No 18, 2006, pp1292-1301), was based on research conducted at the Oncology Division of the University of Navara, in Pamploma, Spain.

In the study 25 patients with indolent follicular lymphoma who had relapsed after chemotherapy (including approximately 1/2 who had received Rituxan therapy) were put into a second remission with CHOP chemotherapy followed by vaccination with anti-idiotype vaccine. Of the 25 patients immunized, 20 developed a measurable anti-idiotype immune response. All of the responders with sufficient follow up for a comparison to be made experienced a second complete response that was significantly longer (P<0.0001) than their first response and than the median length of typical CHOP-induced second complete responses. The authors note that it is highly unusual if not unique that a second remission in this disease would be longer than the first, suggesting that this hybridoma-derived anti-idiotype immunotherapy represents a new treatment paradigm for this disease. Significantly, the median DFS for the second vaccine-associated remission has not been reached, but is >33 months; median DFS for 1st remission was 17 months. The authors conclude that "Specific immune response was associated with a dramatic and highly statistically significant increase in disease free survival. This is the first formal demonstration of clinical benefit associated with the use of a human cancer vaccine." (J Natl Cancer Inst 2006; 98:1292-1301).

Dr. Steve Arikian, Biovest CEO and Chairman commented, "We are very pleased with the results of this new phase 2 trial from the University of Navara. This group used the same hybridoma method to produce their anti-idiotype vaccines as we use at Biovest. We are confident that these impressive results are supportive of the great potential value of our therapy, and even suggest a benefit for extended booster immunizations, for which Biovest will be well prepared when we go to market. We are especially pleased to see that the study suggests a benefit of this therapeutic approach even after relapse following administration of Rituxan. This independent validation comes at a pivotal point in out own trial, as we ramp up patient recruitment and prepare for commercial launch following approval. Our unique ability to efficiently manufacture the active component of these vaccines in our AutovaxID instruments will enable us to meet what we believe will be a significant demand in the worldwide market."

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 developed as an automated vaccine manufacturing instrument and for production of cell-based materials and therapeutics. Biovest's therapy for follicular non-Hodgkin's lymphoma is currently in a Phase 3 pivotal clinical trial at more than 20 major medical centers throughout the U.S. For further information, visit the Company Web site at http://www.biovest.com.

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