Galapagos NV Initiates Second Proof of Mechanism Clinical Study in GlaxoSmithKline Alliance

MECHELEN, BELGIUM--(Marketwire - May 11, 2011) -

·Following successful outcome of first-in-human trial for GLPG0778

·Phase I study measures effect on biomarker in healthy volunteers

Mechelen, Belgium; 11 May 2011 - Galapagos NV (Euronext: GLPG) announced today that it has initiated a second Phase I Proof of Mechanism study in its immuno-inflammation alliance with GlaxoSmithKline. This new study follows the positive outcome of the first-in-human trial conducted for GLPG0778, which showed an acceptable safety and pharmacokinetics profile in healthy volunteers for one- week dosing and an initial biomarker response. The Proof of Mechanism study is aimed at assessing GLPG0778’s effect on a specific target in healthy volunteers.

Galapagos plans to conduct the multiple ascending dose study in 45 healthy volunteers using five two-week dosing regimens. In this Proof of Mechanism study, GPLG0778’s ability to suppress an induced inflammatory response in healthy volunteers will be evaluated. In addition to measuring the biomarker response, the safety, tolerability and pharmacokinetics of candidate drug GLPG0778 will be assessed further. Galapagos aims to report the study results in the fourth quarter of 2011. GSK has an exclusive option to in-license this compound.

“With the initiation of this study, we could demonstrate clinical proof of mechanism for GLPG0778 this year,” said Onno van de Stolpe, CEO of Galapagos. “Together with two other compounds in development, we have multiple programs capable of delivering in the immuno-inflammation alliance with GSK.”

About Galapagos’ immuno-inflammation alliance with GlaxoSmithKline

GSK and Galapagos initiated an alliance to discover and develop disease- modifying drugs for GSK’s global R&D organization in June 2006. GSK and Galapagos expanded the alliance on three occasions to include additional targets. Following the latest expansion in December 2009 and, subject to achievement of milestones Galapagos has the potential to receive more than EUR200 million, plus up to double-digit royalties from GSK. GSK has an exclusive option to further develop and commercialize these compounds on a worldwide basis. Since the start of the immuno-inflammation alliance, Galapagos has received more than EUR60 million in payments from GSK.

About Galapagos

Galapagos (Euronext: GLPG) (PINKSHEETS: GLPYY) is a mid-size biotechnology company specialized in the discovery and development of small molecule and antibody therapies with novel modes-of-action. The Company is progressing one of the largest pipelines in biotech, with six programs in development and over 50 discovery programs. Through risk/reward-sharing alliances with GlaxoSmithKline, Lilly, Janssen Pharmaceutica, Roche and Servier, Galapagos is eligible to receive up to EUR2.5 billion in downstream milestones, plus royalties. The Galapagos Group has over 800 employees and operates facilities in seven countries, with global headquarters in Mechelen, Belgium. More info at: www.glpg.com

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