BioSante Pharmaceuticals Announces New Findings for Potential Bird Flu Vaccine.

LINCOLNSHIRE, Ill. -- BioSante Pharmaceuticals, Inc. (Amex: BPA) today announced new positive results demonstrating that its calcium phosphate (CaP) nanoparticle-based vaccine adjuvant, BioVant[TM], may serve as an effective vaccine adjuvant for the development of a dose sparing vaccine against H5N1 avian flu, widely known as bird flu.

The new results are based on a study using a hemagglutination inhibition assay (HAI), which showed the clear adjuvanting effect of BioVant. After a prime and one booster of BioVant-H5N1-combination-vaccine, the immune response in a rodent model was four-fold that of the H5N1 antigen alone. The study was done with 3 micrograms of H5N1 antigen in each vaccine dose. Earlier this year, the U.S. Food and Drug Administration approved an H5N1 vaccine that uses 90 micrograms of H5N1 antigen by itself given in each of two doses.

"We are working to create a vaccine using our BioVant that would be given at lower doses per injection yet still confer a higher level of immunity than the currently approved vaccine," said Stephen M. Simes, president and chief executive officer of BioSante. "These HAI study results confirm the BioVant antibody results previously reported and add to the data base for a potential BioSante improved BioVant adjuvanted bird flu vaccine."

"According to a paper published in the New England Journal of Medicine, the currently approved bird-flu vaccine without an adjuvant by a European drug company is effective only at high doses (90 micrograms per dose) and only 54 percent of subjects produced the desired immune response. We believe a BioVant-adjuvanted H5N1 vaccine may use less antigen per dose and protect a higher percentage of the population." Mr. Simes continued.

BioSante's preclinical study objective was to determine whether BioVant could enhance the body's natural immune response to the H5N1 viral antigen, the cause of bird flu. At the start of the trial, mice received either the H5N1 antigen alone or in a formulation with BioVant. A booster immunization was administered after two weeks. Results indicated that the administration of a BioVant-H5N1 formulation stimulated production of high titers of H5N1-specific antibodies, which were significantly higher than H5N1 alone. Anti-avian flu antibody levels continued to increase over the entire study period, suggesting good duration of immunity.

Avian flu refers to a large group of different influenza viruses that primarily affect birds. While the vast majority of these viruses do not affect humans, the H5N1 strain already has made the jump from birds to humans and in fact, has infected 310 people and killed 190 since the outbreak of the disease in 2003, and more than 250 million chickens have been killed to stop the spread of the virus. Farmers and poultry producers already have suffered losses in the billions of dollars. There is widespread concern that a strain of avian flu will mutate into a new form that is contagious among humans. Since there is currently no truly effective vaccine available to protect humans from H5N1 and humans do not have antibodies to fight this new virus strain, there is significant risk of a pandemic.

An adjuvant is a substance that, when added to a vaccine, enhances the vaccine's effectiveness by stimulating an immune system response. In multiple studies, BioVant has been shown to be safe and cause minimal dose-dependent inflammation at the injection site, and has been shown to both prevent the manifestation of allergic response, and, to effectively 'switch off' established Th2-T-cell-associated allergic disease.

About BioSante Pharmaceuticals, Inc.

BioSante is developing a pipeline of hormone therapy products to treat both men and women. These hormone therapy products are gel formulations for transdermal administration that deliver bio-identical estradiol and testosterone. BioSante's lead products include Elestrin[TM] (estradiol gel) developed through FDA approval by BioSante indicated for the treatment of moderate-to-severe vasomotor symptoms associated with menopause, marketed in the U.S. by Bradley Pharmaceuticals, Inc., BioSante's licensee, and LibiGel([R]) (transdermal testosterone gel) in Phase III development by BioSante for the treatment of female sexual dysfunction (FSD). Also in development is Bio-T-Gel[TM], a testosterone gel for male hypogonadism, and an oral contraceptive using BioSante patented technology. The current market in the U.S. for estrogen and testosterone products is approximately $2.5 billion and for oral contraceptives approximately $3.0 billion. The company also is developing its calcium phosphate nanotechnology (CaP) for novel vaccines, including hepatitis B, avian flu and biodefense vaccines for toxins such as anthrax, as well as a system for delivering drugs via alternative routes of administration. Additional information is available online at www.biosantepharma.com.

This news release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. The statements regarding BioSante contained in this news release that are not historical in nature, particularly those that utilize terminology such as "may," "will," "should," "would," "likely," "expects," "anticipates," "estimates," "believes," "plans," "hopes," or comparable terminology, are forward-looking statements. Forward-looking statements are based on current expectations and assumptions, and entail various risks and uncertainties that could cause actual results to differ materially from those expressed in such forward-looking statements. Important factors known to BioSante that could cause actual results to differ materially from those expressed in such forward-looking statements include the difficulty of developing pharmaceutical products, obtaining regulatory and other approvals and achieving market acceptance, the success of clinical testing, and other factors identified and discussed from time to time in BioSante's filings with the Securities and Exchange Commission, including those factors discussed in BioSante's most recent annual report on Form 10-K and subsequent quarterly reports on Form 10-Q, which discussions also are incorporated herein by reference. All forward-looking statements speak only as of the date of this news release. BioSante undertakes no obligation to update or revise any forward-looking statement, whether as a result of new information, future events or otherwise.