UPDATE: GLPYY Initiates Phase II Trial for Glpg0634

Galapagos NV announced to-day that it has started a Phase II clinical study for GLPG0634, a novel Janus kinase inhibitor being developed for inflammatory conditions, such as rheumatoid arthritis. In this clinical trial, the efficacy and safety of GLPG0634 will be tested in RA patients, with plans to complete a four-week study by the end of 2011. GLPG0634 is a fully proprietary program which Galapagos intends to partner. "We are pleased to initiate this Proof-of-Concept study for GLPG0634, which marks our second patient trial in rheumatoid arthritis. The current study with GLPG0634 is designed to show a fast onset of clinical response and will be completed by the end of this year," said Piet Wigerinck, SVP Development. "The pre-clinical and Phase I studies for this compound show a specific JAK1 inhibition profile, which could differentiate from other JAK compounds in development." Details of the Phase II clinical trial The clinical Proof-of-Concept Phase II trial for GLPG0634 will involve 36 patients with active rheumatoid arthritis, showing an insufficient response to the standard-of-care treatment, methotrexate. The aim is to evaluate the efficacy and safety of GLPG0634 in treating rheumatoid arthritis. Three groups of 12 patients with moderate to severe disease will receive either a once- or twice-daily dose regimen of GLPG0634 or placebo, for a period of four weeks, while all will continue to take their stable background therapy of MTX. The primary efficacy endpoint will be the ACR20 response rate, the standard primary endpoint for RA clinical trials. Secondary endpoints include improvements in DAS28, ACR50 and ACR70 rates and clinical score. The safety and tolerability, and the harmacokinetics of GLPG0634 in rheumatoid arthritis patients will also be evaluated. Galapagos has received approvals to start the trial at a single Eastern European center, with patient recruitment planned to start in June 2011. The trial has been designed to obtain initial efficacy data by the end of 2011. This phase II trial is part of a broader development program that includes additional pharmacology, Phase I, and preclinical toxicity studies with GLPG0634. The additional studies with GLPG0634 will run in parallel to the efficacy study started to-day, with the aim to prepare for inclusion of additional dosage arms, should this maximize the potential value of the Phase II study.