July 24, 2008

Nabi Reports Positive Interim Results From Phase II Study of Nicotine Vaccine

Nabi Biopharmaceuticals has announced positive interim results from its Phase II NicVAX schedule optimization immunogenicity study to assess the antibody response and safety of a 400 microgram, six dose immunization schedule.

Interim results from the study indicate that significantly higher anti-nicotine antibody levels can be generated three months earlier and in a much higher percentage of subjects than observed in previous NicVAX studies.

Nabi's new immunization schedule, which included an additional injection at three months, resulted in an immune response at 14 weeks that was higher than the peak antibody level achieved following the six month booster in the Phase IIb proof of concept study.

Significantly, the data indicated that more than 80% of subjects achieved the target antibody level at 14 weeks compared to 50% of subjects in the Phase IIb proof of concept study at the same time point. The revised schedule was well tolerated with an adverse event profile comparable to previous NicVAX clinical studies.

NicVAX is an innovative and proprietary investigational vaccine being developed by Nabi to treat nicotine addiction and prevent smoking relapse.

Raafat Fahim, president and CEO of Nabi, said: "We are excited that these initial results strongly support our hypothesis that production of anti-nicotine antibodies can be accelerated and elevated with this revised regimen."