1. NicVAX; An Immunotherapy Aid to Smoking Cessation and Long Term Abstinence February 27, 2011 Raafat Fahim, Ph.D. President and CEO, Nabi Biopharmaceuticals S h a p i n g t h e F u t u r e o f H E A L T H C A R E

2. Nabi Biopharmaceuticals Confidential and Proprietary 2 NicVAX; Significant Unmet Need  Smoking Impact ―1.3 billion smokers Currently, 44 million adult smokers in the U.S. Currently, 44 million adult smokers in the U.S. ―>75% start smoking cigarettes before the age of 18 ―5.4 million deaths/year worldwide ―Smoking is responsible for 1 in 5 deaths in U.S. ―$193 billion in annual healthcare costs associated with smoking- related illness 2 $96 billion in direct healthcare costs 2 $96 billion in direct healthcare costs 2  The Consumer ―Average former smoker makes 8 to 11 attempts to quit ―Only 3–5% of all smokers who try to quit by themselves are permanently successful on any given attempt 4

3. Nabi Biopharmaceuticals Confidential and Proprietary 3 Why do people fail to quit long-term?  Addiction ―<10% (<1:10) remain abstinent at one-year who quit “cold- turkey”  Cravings  Nicotine is freely available and more socially acceptable than other addictive drugs  Habit/psychological cues  Current therapies in combination with behavioral counseling ―One-year continuous abstinence rates: best is ~22% ―Short-acting ―Compliance ―Side-effect concerns

4. Nabi Biopharmaceuticals Confidential and Proprietary 4 Nicotine Addiction

5. Nabi Biopharmaceuticals Confidential and Proprietary 5 NicVAX: 3’aminomethyl Nicotine – Recombinant P. aeruginosa Exoprotein A (rEPA) Conjugate Nicotine N N CH 3 O O O H 2 N N N CH 3 NH NH O O 3’ aminomethyl Nicotine rEPA N N CH 3 NH 2 AMNic rEPA + + + alum (Adjuvant) Nicotine is not immunogenic Upon conjugation to rEPA (NicVAX ) nicotine is rendered immunogenic

6. Nabi Biopharmaceuticals Confidential and Proprietary 6 Breaking the Addiction Cycle

7. Nabi Biopharmaceuticals Confidential and Proprietary 7 Inhibitor Rabbit Serum Rabbit IgG Nicotine>90%>90% (-)-Cotinine0.63.1 (±)-Nornicotine0.20.4 (-)-Nicotine-N-Oxide0.62.0 (-)-Nicotine-N’-Oxide0.01<0.01 (±)-Norcotine<0.01nd Trans-3’-hydroxy-(-)-cotinine<0.01nd (-)-Cotinine-N-Oxide<0.01nd Acetylcholine-HCl<0.01nd GABA<0.01nd Serotonin HCL <0.01nd Iproniazid phosphate <0.01nd Buspirone HCl <0.01nd G-vinyl-GABA (vigabatrin) <0.01nd Bupropion HCL (Zyban) <0.01nd Creatinine<0.01nd Niacin<0.01nd L-Proline<0.01nd NicVAX Induces Antibodies Specific to Nicotine, Not to Nicotine Metabolites or Related Molecules  Specificity, (binding) of antibodies to nicotine induced by vaccination with NicVAX  Specificity was determined by inhibition ELISA nd=not determined

8. NicVAX Preclinical Studies and Theoretical Mechanism of Action (Clinical relevance unknown) S h a p i n g t h e F u t u r e o f H E A L T H C A R E

9. Nabi Biopharmaceuticals Confidential and Proprietary 9 Animals Actively Immunized with NicVAX Demonstrate Sequestering of Nicotine within the Bloodstream  1 Minute after Nicotine 0.1 mg/kg i.v. (~ 6-7 cigs) Satoskar, S. et al, Int Immunopharmacol 2003;3:957

10. Nabi Biopharmaceuticals Confidential and Proprietary 10 Pentel et al SRNT 2005 Nicotine Half-Life is Significantly Extended in Vaccinated Animals NicVAX vaccinated individuals may experience attenuated withdrawal symptoms due to the increased nicotine half-life (t 1/2 ) from hours to days

11. Nabi Biopharmaceuticals Confidential and Proprietary 11 In Animal Models, NicVAX Demonstrated Consistent Efficacy  Antibodies to NicVAX ―Neutralized the pharmacological effects of nicotine on blood pressure 1 blood pressure 1 locomotor activity 2 locomotor activity 2 nicotine discrimination 3 nicotine discrimination 3 diminishes NSA 4 diminishes NSA 4 ―Prevented drug dependence and addiction when administered prophylactically 5 ―Administration during nicotine exposure prevented onset of withdrawal symptoms in animals 6 1 Pharm Biochem Behav 2000;66:191 2 Bioorg Med Chem 2004;12:563 3 Life Sci 2002;70:2793 4 LeSage et.al Psychopharmacology 2005 5 Resp 2002;69(3):247 6 Pharm Biochem Behav 2001:68:87

12. Nabi Biopharmaceuticals Confidential and Proprietary 12 NicVAX Elicited Polyclonal Antibodies Display “Monoclonal-like” Specificity : > 90% Competitive Inhibition with a Single NicVAX mAb Rabbit Rat NicVAX Mc-431 (Competitor) against Polyclonal Antibodies (Primary) on 3’AMNic-Coated Plates

13. Nabi Biopharmaceuticals Confidential and Proprietary 13 “Monoclonal Nature” also Observed in NicVAX Immunized Subjects

14. Nabi Biopharmaceuticals Confidential and Proprietary 14 Day 0 1 Month 2 Month 3 Month 4 Month Upon smoking; nicotine travels quickly to the brain Untreated Smoker illustrative

15. Nabi Biopharmaceuticals Confidential and Proprietary 15 Day 0 1 Month 2 Month 3 Month 4 Month NicVAX Injections Effective number of cigarettes “seen” by the brain decreases with time, making it easier to quit … Antibodies partially shield the brain from nicotine Path to Continuous Abstinence along with the Potential to Reduce Cravings and Withdrawals illustrative

16. Nabi Biopharmaceuticals Confidential and Proprietary 16 Day 0 1 Month 2 Month 3 Month 4 Month NicVAX Injections Supportive Counseling Antibodies partially shield the brain from nicotine Easier to Quit Smoking Target Quit Date Successful Quit illustrative Brain exposure to nicotine was reduced gradually with the rise of antibodies Bound/free nicotine equilibrium results in continuous low levels of free nicotine Antibodies persistence for months Aligned quit date and counseling with high antibodies Brain exposure to nicotine was reduced gradually with the rise of antibodies Bound/free nicotine equilibrium results in continuous low levels of free nicotine Antibodies persistence for months Aligned quit date and counseling with high antibodies Path to Continuous Abstinence along with the Potential to Reduce Cravings and Withdrawals

17. NicVAX Clinical Development S h a p i n g t h e F u t u r e o f H E A L T H C A R E

18. Nabi Biopharmaceuticals Confidential and Proprietary 18 Objectives of the Phase I/II program  Evaluate tolerability and safety of NicVAX in non-smokers and smokers  Understand the immune response to NicVAX ―Determine Dose level and number of doses Dose level and number of doses Administration schedule Administration schedule  Demonstrate proof of concept that antibodies to nicotine are useful in treating nicotine dependence

19. Nabi Biopharmaceuticals Confidential and Proprietary 19 NicVAX Phase 2b Trial Design  Multi-center, randomized, double-blind, placebo controlled study in smokers who want to quit smoking  301 heavy smokers ―Average of 24 cigarettes per day; no smoker less than 15/day  2 dose levels (400 µg and 200 µg) vs. placebo  4 and 5 injection schedules tested and pooled for POC

20. Nabi Biopharmaceuticals Confidential and Proprietary 20 Safety & Tolerability Summary  NicVAX was safe with no significant SAEs. No difference between placebo and NicVAX  Similar observations for all other studies to date  Most common local reactogenicity events ―Ache ―Tenderness  Most common systemic reactogenicity events ―General discomfort/malaise ―Headache ―Muscle aches  Events were generally mild to moderate in severity and resolved quickly  Incidence of events did not increase after subsequent vaccinations

21. Nabi Biopharmaceuticals Confidential and Proprietary 21 Adverse Events NicVAX n=201 Placebo n=100 Upper Respiratory Infection 29%30% Headache12%12% Insomnia10%9% Nasopharyngitis9%14% Nausea7%10% Dizziness6%11% All events ≥ 10% of either NicVAX or Placebo

22. Nabi Biopharmaceuticals Confidential and Proprietary 22 Antibody Response by Treatment Arm Intent to Treat Population TQDTQD 4 Injections 5 Injections Schedule 1 Schedule 2 TQD is fixed at 1 week post 2 nd injection

23. Nabi Biopharmaceuticals Confidential and Proprietary 23 Proportion of Subjects Quit Each Week: Point Prevalence Stratified by Antibody Levels *Top 30% by AUC N=18/61 p=0.0055 N=17/140 N=12/100 All NicVAX Subjects: ITT TQD

24. Nabi Biopharmaceuticals Confidential and Proprietary 24 Continuous Abstinence 6-Month (8Wk 19-26) 12-Month 44-Week NicVAX High Antibody* 25%(n=15/61)p=0.0418%(n=11/61)p=0.01 NicVAX Low Antibody 10%(n=14/140)p=0.478%(n=11/140)p=0.49 Placebo 13% (n=13/100) 6% (n=6/100) Antibody-dependence of Abstinence : ITT Primary Endpoint (POC) and Follow up * Top 30% by AUC per protocol Schedule 1 & Schedule 2 pooled

25. Nabi Biopharmaceuticals Confidential and Proprietary 25 NicVAX Long-term Efficacy before Regimen Optimization Similar to Marketed Rx Therapies Treatment 44-Week Continuous Abstinence Active ActivePlacebo Therapeutic Effect varenicline (Chantix) Pfizer Phase III 21-22%8-10%13%OR=3.13 bupropion (Zyban) Pfizer Phase III – comparator arm 14-16%8-10%6%OR=<2 NicVAX 5 x 400  g Nabi Phase IIb 16%6%10%OR=3.44 Intent to Treat Population in all cases Intended for comparative purposes only & does not reflect head to head study

26. NicVAX Correlation between Antibody Levels and Smoking Cessation Phase IIb S h a p i n g t h e F u t u r e o f H E A L T H C A R E

27. Nabi Biopharmaceuticals Confidential and Proprietary 27 High Antibody Levels Support Sustained Quit in 5 Injection Regimen (Nabi-4512) N=12/30 N=8/71 N=12/100 NicVAX Subjects: 5 Injection Regimen TQD Quit for at least 8 weeks continuously and remaining continuously abstinent to study end

28. Nabi Biopharmaceuticals Confidential and Proprietary 28 Antibody Dose-Response (Abstinence at 12-months) Top 30% NicVAX Subjects: 5 Injection Regimen

29. Nabi Biopharmaceuticals Confidential and Proprietary NicVAX ITT : Ab Levels after Each Injection Correlate with LT Efficacy 2nd Injection 3rd Injection 4 th Injection 29

30. Nabi Biopharmaceuticals Confidential and Proprietary 30 Antibody-Dependent Reduction in Cigarette Consumption in Non-Abstainers All NicVAX Subjects: ITT

31. Nabi Biopharmaceuticals Confidential and Proprietary 31 Reduced Clinical/Regulatory Pathway Risk  Successful EOP2 meeting with the FDA: ―No concerns with pre-clinical safety or CMC to initiate phase III studies ―Agreed with phase III design and end points ―Encouraged Nabi to submit an SPA  Approved SPA package: ―FDA approved design and end points in a letter to Nabi  Received scientific advice from EMA ―Supports Phase III trial design  Pivotal Phase 3 studies initiated ―First trial November 2, 2009 – Results anticipated 2 nd half, 2011 ―Second trial March 17, 2010 – Results anticipated 1 st half, 2012 31

32. Nabi Biopharmaceuticals Confidential and Proprietary 32 TQD 83% Responders % Above Target Ab levels by Number of Injections ITT Population Nabi-4513 vs. Nabi-4512 7% 50%

33. Nabi Biopharmaceuticals Confidential and Proprietary 33 Key Findings: Implications for NicVAX Phase III Trial Design  The 400 µg doses induce high antibody levels  Six doses maintain long-term, high antibody levels in circulation => Abstinence is sustained to 12 months  Alignment of target quit date with peak antibody levels will enhance effectiveness => move TQD to Week 14 (previously Week 5)  Additional dose at week 12 further increase Ab levels earlier; evaluated in a separate study prior to phase III  Increasing supportive counseling consistent with other marketed therapies may improve abstinence rates  Vaccine education incorporated in the study 33

34. Nabi Biopharmaceuticals Confidential and Proprietary 34 Principal Design Changes for Phase III Phase IIb Proof-of-Concept   Five injections, 400 µg, at weeks 0,4,8,16 & 26   Target Quit Date Week 5   One trial x 301 participants   8 research sites   Smoke ≥ 15 cigarettes /day   Minimal counseling Phase III Efficacy/Safety  Six injections, 400 µg at weeks 0,4,8, 12, 16 & 26  Target Quit Date Week 14  2 trials x 1000 participants  22 and 25 research sites  Smoke ≥ 10 cigarettes/day  Standard-of-care counseling ―Aligned with Target Quit Date and high antibody level

35. Nabi Biopharmaceuticals Confidential and Proprietary 35 Phase III Studies  Two multi-center, double-blind, placebo- controlled randomized trials, Nabi-4514 and Nabi-4515 ―Nearly identical trials, 1000 patients each ―22 to 25 sites per study ―Mix of academic medical center-based and community-based sites

36. Nabi Biopharmaceuticals Confidential and Proprietary 36 NicVAX Injections 8 4 4 months of abstinence 1626 Four injections supports quitting at TQD Six injections series supports long-term abstinence TQD 0 52 12 Nabi-4514 & Nabi-4515: DB, Placebo-controlled Phase III Studies to Assess NicVAX as an Aid to Smoking Cessation & Long-term Abstinence + placebo injections 1 o Endpoint Abstinence at one year

37. Nabi Biopharmaceuticals Confidential and Proprietary 37 NicVAX Licensed to GlaxoSmithKline  Exclusive worldwide option and licensing agreement to: ―Develop, commercialize and manufacture NicVAX & NicVAX Alternatives ―Develop, commercialize and manufacture future generation vaccines  More than $500 million upfront and potential consideration  Transaction closed ―Approved by Nabi shareholders March 2, 2010 ―Agreement closed March 8, 2010

38. Nabi Biopharmaceuticals Confidential and Proprietary 38 Status of Efficacy Studies  Two 1000 Subject Phase III studies on-going ―1 st Study, Completion of enrollment announced: July 2010 ―2 nd Study, Completion of enrollment announced: November 2010  Anticipate final results of 1 st Phase III (Nabi- 4514) in 2 nd half of 2011  Anticipate final results of 2 nd Phase III (Nabi- 4515) in 1 st half of 2012

39. Nabi Biopharmaceuticals Confidential and Proprietary 39 Summary  NicVAX holds potential as an additional aid to smoking cessation and relapse prevention  Reduced clinical risk ―Dose selected and optimized regimen established ―Aligned target quit date with peak antibody levels  Reduced regulatory risk ―Both Phase III studies initiated ―SPA approved by FDA ―Scientific advice from EMEA  Reduced commercial risk ―GSK’s worldwide commercialization reach ―Well positioned to be first smoking cessation vaccine to market “Shifting the smoking-cessation therapeutic paradigm from quit to continuous abstinence”