An Open-label, Long-term Extension Study With Filgotinib in Active Psoriatic Arthritis.

Study Overview
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Brief Summary
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This is a Phase 2, multicenter, open-label, single arm, Long Term Extension (LTE) safety, tolerability and efficacy study of filgotinib in subjects with moderately to severely active PsA. It is estimated that approximately 105 subjects will be rolled-over after they have completed the 16 weeks of double-blind treatment in core study GLPG0634-CL-224. Subjects will be administered filgotinib in this study until filgotinib is registered for PsA or until Week 304, whichever occurs first. The LTE study is concluded with a follow-up visit approximately 4 weeks after the last intake of study treatment.

Official Title
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A Multicenter, Open-label, Long-term Extension Safety and Efficacy Study of Filgotinib Treatment in Subjects With Moderately to Severely Active Psoriatic Arthritis.

Conditions
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Psoriatic Arthritis

Intervention / Treatment
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* Drug: filgotinib


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Male or female subjects who are ≥18 years of age, having completed the 16 weeks of treatment in the qualifying core study GLPG0634-CL-224 and who may benefit from filgotinib long-term treatment according to the investigator's judgment. Male and female subjects of childbearing potential who engage in heterosexual intercourse must agree to continue to use highly effective methods of contraception as described in the protocol. Able and willing to sign the informed consent form (ICF), as approved by the Independent Ethics Committee (IEC) and agree to the schedule of assessments. Exclusion Criteria: Subjects who are deemed not to be benefitting from the study drug based upon lack of improvement or worsening of their symptoms. Local guidelines for subject treatment need to be followed. Persistent abnormal laboratory values associated with the use of the study drug (including and not limited to hematology, liver and renal function values), according to the investigator's clinical judgment. Subjects who discontinued the qualifying core study GLPG0634-CL-224 due to safety or tolerability issues. Subjects who require immunization with live/live attenuated vaccine. Diagnosis of rheumatic autoimmune disease or inflammatory joint disease other than psoriatic arthritis, except for Sjögren's syndrome. Subjects with symptoms suggestive of uncontrolled hypertension, congestive heart failure, uncontrolled diabetes, cerebrovascular accident, myocardial infarction, unstable angina, unstable arrhythmia or any other cardiovascular condition since the inclusion to the GLPG0634- CL-224 study. Subjects with symptoms suggestive of gastrointestinal tract ulceration and/or active diverticulitis since the inclusion to the GLPG0634-CL-224 study. Subjects with symptoms suggestive of possible lymphoproliferative disease including lymphadenopathy or splenomegaly since the inclusion to the GLPG0634-CL-224 study. Subjects with symptoms suggestive of malignancy since the inclusion to the GLPG0634-CL-224 study.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: filgotinib<br> | Drug: filgotinib<br>* one filgotinib oral tablet once daily.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in the proportion of subjects with adverse events | To asses safety and tolerability of filgotinib. | Between entry visit and 4 weeks after the last dose. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Proportion of subjects achieving minimal disease activity (MDA) | To assess the effect of filgotinib on MDA in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Proportion of subjects achieving American College of Rheumatology 20 (ACR20) response | To assess the effect of filgotinib on PsA as assessed by ACR20 in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Proportion of subjects achieving ACR50 response | To assess the effect of filgotinib on PsA as assessed by ACR50 in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Proportion of subjects achieving ACR70 response | To assess the effect of filgotinib on PsA as assessed by ACR70 in PsA patients | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Proportion of subjects with Psoriatic Arthritis Disease Activity Score (PASDAS) low disease activity (LDA, i.e. PASDAS ≤ 3.2) | To assess the effect of filgotinib on PsA as assessed by PASDAS in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Proportion of subjects with PASDAS Very Low Disease Activity (VLDA) (i.e. PASDAS ≤1.9) | To assess the effect of filgotinib on PsA as assessed by PASDAS in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Percentage of patients subjects with PASDAS LDA (i.e. PASDAS ≤3.2) | To assess the effect of filgotinib on PsA as assessed by PASDAS in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Percentage of patients subjects with PASDAS VLDA (i.e. PASDAS ≤1.9) | To assess the effect of filgotinib on PsA as assessed by PASDAS in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Change from core baseline in Disease Activity Index for Psoriatic Arthritis (DAPSA) | To assess the effect of filgotinib on PsA as assessed by DAPSA in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Proportion of subjects with DAPSA remission/LDA (DAPSA ≤14) | To assess the effect of filgotinib on PsA as assessed by DAPSA in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Proportion of subjects with DAPSA remission (DAPSA ≤4) | To assess the effect of filgotinib on PsA as assessed by DAPSA in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Change from core baseline in Psoriasis Area and Severity Index (PASI) | To assess the effect of filgotinib on PASI in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Proportion of subjects with PASI50 | To assess the effect of filgotinib on PASI50 in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Proportion of subjects with PASI75 | To assess the effect of filgotinib on PASI75 in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Proportion of subjects with PASI90 | To assess the effect of filgotinib on PASI90 in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Proportion of subjects with PASI100 | To assess the effect of filgotinib on PASI100 in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Change from core baseline in Physician's global assessment of psoriasis | To assess the affect of filgotinib on Physician's global assessment of psoriasis in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Change from core baseline in Patient's Global Assessment of psoriasis | To assess the affect of filgotinib on patient's global assessment of psoriasis in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Change from core baseline in modified Nail Psoriasis Area and Severity Index (mNAPSI) | To assess the effect of filgotinib on mNAPSI in PsA patients assessment of psoriasis in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Change from core baseline in pruritis numeric rating scale (NRS) | To assess the effect of filgotinib on NRS in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Proportion of subjects achieving a pruritis numeric rating scale (NRS) response(improvement in pruritus NRS score of ≥3) | To assess the effect of filgotinib on NRS in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Change from core baseline in the Spondyloarthritis Research Consortium of Canada (SPARCC) enthesitis index | To assess the effect of filgotinib on SPARCC enthesitis index in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Change from core baseline in Leeds Dactylitis Index (LDI) | To assess the effect of filgotinib on Dactilytis in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Change from core baseline in Health Assessment Questionnaire-Disability Index (HAQ-DI) | To assess the effect of filgotinib on physical function in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. | 
| Change from baseline in Functional Assessment of Chronic Illness Therapy Fatigue Scale (FACIT-Fatigue scale) | To assess the effect of filgotinib on FACIT-Fatigue scale in PsA patients. | W4, W52, W100, W148, W172, W196, W220, W244, W268, W292, W304. | 
| Change from core baseline in 36-item Short-Form Health Survey (SF-36) | To assess the effect of filgotinib on SF-36 in PsA patients | W4, W52, W100, W148, W172, W196, W220, W244, W268, W292, W304. | 
| Change from core baseline in Psoriatic Arthritis Impact of Disease Questionnaire (PsAID). | To assess the effect of filgotinib on PsAID in PsA patients. | W4, W52, W100, W148, W172, W196, W220, W244, W268, W292, W304. | 
| Change from core baseline in individual components of the ACR response of improvement in multiple disease assessment criteria | To assess the effect of filgotinib on signs and symptoms of peripheral arthritis and physical function in PsA patients. | At each on-site visit until filgotinib is registered for PsA or until Week 304, whichever occurs first. |