SWEDISH-AMERICAN LIFE SCIENCE SUMMIT August 19-21, 2009

An Introduction to Affibody Corporate Background  Privately held (HealthCap 43%, Investor 25%)  Founded in 1998 by scientists from KTH and KI  Based in Stockholm, Sweden  25 FTEs Technology Platforms  Affibody® platform - high affinity binders  Albumod TM platform - extending the half life of biotherapeutics Business Model  Balanced business model generating SEK 28m (~USD 3.5m) in revenue 2008  10 deals with partners such as GE, Merck, Biovitrum, and Finnzymes  4 industrial products marketed by partners Second generation antibody mimetics company

N N Affibody ® Technology – Proprietary Triple Helical Platforms Affibody ® Platform Albumod TM Platform 5 kDa6 kDa Two proprietary platforms – versatile business model

The Antibody Opportunity  More than 20 approved therapeutic mAbs  Blockbusters such as Rituxan ®, Remicade ®, Herceptin ®, Avastin ®, Humira ®, Erbitux ®, and Synagis ®  Therapeutic mAb revenue projected at above USD 30bn in ’09  Expected 5-yr Sales CAGR >10%  Large pipeline of products in late-stage development Monoclonal Antibody (mAb) Monoclonal antibodies are reshaping the industry Therapeutic mAbs

Affibody ® molecule 6 kDa Monoclonal Antibody (mAb) 150 kDa Affibody ® Molecules – Next Generation Antibody A fraction of the size packed with the same power  Small size (1/25th the size of a mAb)  High selectivity and affinity (high potency)  Rapid and reversibly folding (extreme stability)  Flexible low cost production (peptide synthesis or recombinant production)  Flexible engineering and formatting (modified properties and formats)

Anti-HER2 Affibody ® Molecule vs. Trastuzumab When you can see it you can treat it mAb  High background  Extended exposure of non-target organs 6 h p.i. 124 I-Trastuzumab, N87 Xenografted mice 124 I-Anti-HER2 Affibody® Molecule, N87 Xenografted mice 24 h p.i. Affibody ® Molecule  Rapid high tumor uptake  Improved potency / side- effect ratio

N N Affibody ® Technology – Proprietary Triple Helical Platforms Affibody ® Platform Albumod TM Platform 5 kDa6 kDa Two proprietary platforms – versatile business model

Albumod TM Platform – Extending Half-Life  Potency – sustained efficacy  Economy – reduced dosage  Safety – avoid high peak blood concentrations  Life cycle management / Biosuperiors Half Life from Minutes to Days (primate) 5-fold Higher Dose on Tumor (mouse) Half-life: from hours to days  increased potency

Therapeutics and Imaging Portfolio Overview ProgramPreclinical Research Anti-HER2 Affibody® Molecule Clinical Development Target Selection Lead Identification Lead Optimization Preclinical Breast Cancer, Phase I/IIa study approved, exploratory clinical data Bladder Cancer, Phase I study approved Breast and Bladder Cancer, pre-clinical efficacy Phase I Phase II Phase III Therapeutics Imaging Oncology Anti-EGFR Affibody® Molecule Head and Neck Cancer, ready for development Anti-PDGFRβ Affibody® Molecule Anti-PSMA Affibody® Molecule Cancer, ready for development Prostate Cancer Inflammation and autoimmune Undisclosed Hematology Long-acting G-CSF Neutropenia,PK data

HER2 Program (Imaging and Therapy)

Anti-HER2 Affibody ® Molecule Imaging Opportunity Breast Cancer  Exploratory clinical data available  Phase I dose finding study approved Bladder Cancer Imaging  Exploratory application approved Safety and Immunology  Repeated dose tox demonstrated the molecule to be safe and well tolerated  Non-immunogenic after repeated dosing in rat Clinical Development Plan  Phase I dose finding study (27 patients, 6 months)  Phase III confirmatory study ( patients, 9 months) Breast Cancer patient with brain metastasis Short time to market – limited number of patients

Orlova, A., et al. (2007) Cancer Research, 67: HER2 Imaging – Novel Diagnostic Applications Use cases demonstrated not possible with current standard (biopsy) CORONALTRANSVERSAL Global HER2 status (2 h p.i., PET/CT) Tumor 17-AAG treated Monitoring therapy response (4 h p.i., SPECT)

Trends in Oncology mAb Therapy  Antibody-drug conjugation (payloads) –T-DM1 (Herceptin + payload), Ph III, Genentech/ImmunoGen Genentech plans to file 1-2 INDs on payload drugs annually –SGN-35 (CD30 + payload), Ph III, Seattle Genetics  Focus on effector functions –e.g. Xencor, Macrogenics, Glycart, Micromet – BiTE, Merrimack – HER2/HER3 The Affibody ® molecule is an optimal payload carrier

Saline Toxin fusion 250  g/kg Tumor volume BT474 Xenografts PE38 toxin Anti-HER2 Affibody ® Molecule – Payload Therapeutics Therapeutic Efficacy - HER2 Affibody ® Toxin Fusion Protein HER2 Affibody ® Toxin Fusion shrinks solid tumors

Long-acting G-CSF (Therapy)

Long-acting G-CSF – A Biosuperior Opportunity A single i.v. injection of equimolar amounts of G-CSF-ABD0 fusion (n=5) or G-CSF (Neupogen®) (n=2) to rats 10-Fold Increased Circulation Time Retained Specific Activity 10x increased circulation time and fully retained activity NFS-60 proliferation assay

Achievements During 2009  Therapeutics –Preclinical efficacy demonstrated in collaboration with NCI (HER2) –Prolonged circulation time with retained activity demonstrated (G-CSF)  Medical Imaging –Approved Swedish Bladder Cancer Imaging Study –Approved German Breast Cancer Imaging Study  Business Development –Collaboration with Biovitrum –New deals currently negotiated Considerable achievements during 2009

The Value of Antibody Mimetics – Example of Deals Amgen acquired Avidia for $290m (2006)  Amgen bought Avidia to get access to a small scaffold protein, based on only early preclinical data. Pfizer bought BioRexis for an unknown amount (2006)  The acquisition gave Pfizer proprietary rights to transferin as a scaffold, and for halflife extension of peptides. Only preclinical data were available at the time of purchase. GSK acquired Domantis for $455m (2006)  Domantis was a domain antibody scaffold company. Only preclinical data were available at the time of purchase. BMS bought Adnexus for $430 million (2007)  Adnexus had proprietary rights to fibronectin as a scaffold, and for halflife extension of peptides. Only preclinical data were available at the time of purchase. Significant values have been realized by similar technologies

Investment Case  Balanced portfolio – therapeutics and diagnostics –From imaging to therapy in oncology –Excellent payload carrier  Growing revenue stream –Primarily driven by royalty revenue  Validating collaborations Positioned to capitalize on the next wave of antibody therapeutics