Nabi Biopharmaceuticals Announces Results of First NicVAX(R) Phase III Clinical Trial

Smoking Cessation Immunotherapy Failed to Meet Primary Endpoint

ROCKVILLE, Md., Jul 18, 2011 (GlobeNewswire via COMTEX) -- Nabi Biopharmaceuticals today announced that NicVAX(R) (Nicotine Conjugate Immunotherapeutic) did not meet its primary endpoint in the company's first of two confirmatory Phase III clinical trials.

A preliminary assessment of the trial data showed that subjects treated with NicVAX quit smoking at a similar rate of approximately 11% compared to subjects who received placebo. As in previous trials, NicVAX was well-tolerated with a clinically acceptable safety and tolerability profile.

The study was a double-blinded, placebo-controlled trial of 1,000 patients. The primary endpoint of the study was the abstinence rate for 16 weeks ending at 12 months. Abstinence was evaluated by self-reported cigarette consumption and biologically verified by exhaled carbon dioxide. Secondary endpoints included the abstinence rate at various time intervals, safety and immunogenicity, and the effect of NicVAX on withdrawal symptoms, cigarette consumption, smoking satisfaction and nicotine dependency.

"We are clearly surprised and deeply disappointed with the results of this first NicVAX Phase III trial," Raafat Fahim, President and Chief Executive of Nabi Biopharmaceuticals said. "We are in the process of assessing the reasons for these unexpected data, as we await the results of the second Phase III trial. Data from this second trial may provide clues that could help explain the disappointing results from the first trial. In the meantime, the board of directors is actively evaluating any and all appropriate strategic alternative actions to preserve shareholder value, while management is working to further control the operational expenses of the company."

The company will host a live webcast at 10:00 a.m. EDT today to discuss these results.

The live webcast can be accessed at: http://phx.corporate-ir.net/phoenix.zhtml?p=irol-eventDetails&c=100445&eventID=4158429

Due to the length of this URL, it may be necessary to copy and paste this hyperlink into your browser. Remove the space if one exists. The webcast may also be accessed via the Nabi Biopharmaceuticals website at http://www.nabi.com .

If you do not have Internet access, the U.S./Canada call-in number is 800-573-4752 and the international call-in number is 617-224-4324. The passcode is 89450143. An audio replay will be available through July 25, 2011 for U.S./Canada callers at 888-286-8010 and for international callers at 617-801-6888. The replay passcode is 91153608.

The press release and an archived version of the webcast will be available on the company's website at http://www.nabi.com .

About the Phase III Study

The initial Phase III study for NicVAX is a double-blinded, placebo-controlled study comprised of approximately 1,000 patients. The primary endpoint of the study is the abstinence rate at 12 months as measured from week 37 through week 52. Abstinence was evaluated by self-reported cigarette consumption and exhaled carbon dioxide. Secondary endpoints included the abstinence rate at various time intervals, safety and immunogenicity, and the effect of NicVAX on withdrawal symptoms, cigarette consumption, smoking satisfaction and nicotine dependency. This study was supported by Award Number RC2DA028837 from the National Institute On Drug Abuse. The content of this news release is solely the responsibility of Nabi Biopharmaceuticals and does not necessarily represent the official views of the National Institute On Drug Abuse or the National Institutes of Health.

About Nabi Biopharmaceuticals

Nabi Biopharmaceuticals leverages its experience and knowledge in powering the immune system to develop products that target serious medical conditions in the areas of nicotine addiction and gram-positive bacterial infections. Nabi Biopharmaceuticals is currently developing NicVAX(R) (Nicotine Conjugate Vaccine), an innovative and proprietary investigational vaccine for treatment of nicotine addiction and prevention of smoking relapse. The company is headquartered in Rockville, Maryland. For additional information about Nabi Biopharmaceuticals, please visit www.nabi.com .