1. Galapagos: a new force in drug discovery Onno van de Stolpe – CEO IEX Beleggen in Biotech Dag May 20, 2006

2. 2 2005 – The year of ‘bold moves’ May: IPO on Euronext Brussels & Amsterdam September: Successful bid on BioFocus – listing on AiM

3. 3 Raises € 22M with IPO Up 32% since IPO, market cap ~ € 115M biotech IPO Europe 14%, US -10% Bid on BioFocus Offer on BioFocus closed Offer on BioFocus unconditional + 32% 2005 – The year of ‘bold moves’

4. 4 Share capital & history Founded 1999 by Crucell & Tibotec € 23 M financing: top tier VC’s 2002 IPO: € 22 M raised BioFocus acquisition: 29% of Group shares Shares: 13,050,743 April 2006 Crucell 9% Tibotec 9% VC's -Burrill 7% VC's -Alpinvest 4% VC's - Apax 10% VC's - Abingworth 11% Free float 50%

5. 5 Target identification Target validation Assay development Preclinical testing Clinical trials I, II, III Screening Lead optimization Find human protein responsible for disease Identify chemical compound that binds to protein Develop compound into drug candidate Test drug candidate Galapagos: from protein to drug Too much/little of target protein Correct level of target protein

6. 6 Galapagos group – business model Proprietary target & drug discovery platform fee for service offering therapeutic programs novel drug candidates Partnering in: pre-clinical phase I phase II bone & joint diseases € NL & UK 160 employees Belgium 60 employees

7. 7 High value deals within reach BioFocus participates in € 3- 4 B drug discovery service market Target identification Target validation Assay development Preclinical testing Clinical trials I, II, III Screening Lead optimization BioFocus: gene-to-candidate-drug capabilities Market set to grow at > 18 % growth per year Pharma key drivers R&D outsourcing:  focus on core competencies  access novel technologies  improve speed to market

8. 8 From idea to preclinical candidate Turnkey deal negotiation: multi year alliance 1.5 year 2 years To targets To Proof of Concept To drug candidate target identification assay development screening medicinal chemistry preclinical development Time per phase

9. 9 Galapagos internal programs Rheumatoid arthritis Osteoporosis Osteoarthritis Diseases Ageing population Bone & joint diseases market estimate: € 21 billion Underserved medical need

10. 10 Lead optimization Pre-clinical studies Phase IPhase IIPhase III 2006-20072007-200820092010 20112013 Road to a new drug Scenario for Galapagos RA program out licensing to big pharma Phase Year

11. 11 RA program: from target to drug Small molecules inhibiting cartilage degradation Inhibition of cytokine-induced MMP1 Inhibition of cytokine-induced collagen degradation LPS/TNF  profiling IP/literature/drugability/safety profile 323 192 4,611 152 48 14 Targets to enter drug discovery, including target GT418 screened genes Expression profiling/knock-in validation

12. 12 RA mouse model treated with Galapagos molecule (40mg/kg, oral) Significant reduction in disease-causing cytokines Minimal impact on other cytokines Untreated Treated Untreated Treated Untreated Treated Untreated Treated 0 20 40 60 80 100 TNF-  IL-6GM-CSF IL-4 % cytokine Proof of Principle in RA

13. 13 From target to Proof of Concept Discovered protein responsible for RA in human primary cells Identified molecule that binds to protein Chemical molecule effective in mouse RA model  Reduction in cytokines  Reduction in paw swelling development Improved chance that molecule will be effective in human RA patients

14. 14 Acceleration at a glance 0 2 4 6 8 10 12 in € millions 030405 6.5 7.8 11.2 R EVENUES 0 1 2 3 4 5 6 7 8 9 in € millions 030405 5.4 6.7 R&D E XPENSE 0 5 10 15 20 25 in € millions 030405 13.0 10.3 23.6 C ASH P OSITION

15. 15 Group revenues guidance in € millions 030405 6.5 7.8 17.5 06 25 - 30 30 25 20 15 10 5 Galapagos 2006 Guidance on 40-70% growth on pro forma 2005

16. 16 R&D expense drug discovery in € millions 030405 5.4 6.7 8 6 4 2 Increase in R&D 2005: 24% 2006: 34% (guidance) 06 9.0

17. 17 Bring own products into clinic Grow service business through organic growth and acquisitions Establish strategic alliances through turn key deals with big pharma Use BioFocus as cash generator for internal development Become Europe’s leading biotech

18. 18 Drive internal drug discovery programs  Lead optimization RA  Proof of Concept in OA and/or OP Strengthen pipeline  In-license candidate drug, or  Acquire product company Sign turn key alliance with big pharma Grow service business through organic growth and acquisitions Grow revenues with 40-70% 2006 outlook Strong newsflow

19. 19 FortisBuy€ 12Geraldine O’Keeffe KBCOutperform€ 10.5Christophe Van Vaeck KempenBuy€ 12Mutlu Gundogan RabobankHold€ 9.5Mark van der Geest Analyst recommendations

20. 20 www.glpg.com