Study to Evaluate the Effect of Filgotinib on Semen Parameters in Adult Males With Active Rheumatoid Arthritis, Psoriatic Arthritis, Ankylosing Spondylitis, or Non-radiographic Axial Spondyloarthritis

Percentage of Participants With a ≥ 50% Decrease From Baseline in Sperm Concentration at Week 26

Arthritis responder: For rheumatoid arthritis (RA), psoriatic arthritis (PsA), ankylosing spondylitis (AS), and non-radiographic axial spondyloarthritis (nrAxSpA), a participant with an improvement in the Physician's Global Assessment of Disease Activity (PhGADA) of at least 20% compared with baseline (Day 1) at the specified assessment time. Arthritis nonresponder: For RA, PsA, AS, or nrAxSpA, a participant who did not fulfill the definition of arthritis responder at the specified assessment timepoint. PhGADA: Physician measured the participant's disease severity on a visual analogue scale (VAS) ranged from 0 (no disease)-100 (worst disease) millimeters (mm). Baseline value for sperm/semen parameters was the mean of 2 evaluable semen collections at the screening visit. The normal range for sperm concentration is ≥15 million sperms/mL. Percentage change = (\[mean at Week 26 - baseline\] / baseline) × 100; value at Week 26 was the mean of 2 evaluable samples collected at Week 26.

Time frame: Baseline to Week 26

Change From Baseline in Sperm Total Motility at Week 13

The normal range for sperm total motility is ≥40%.

Time frame: Baseline, Week 13

Change From Baseline in Sperm Total Motility at Week 26

Arthritis responder: For RA, PsA, AS, and nrAxSpA, a participant with an improvement in the PhGADA of at least 20% compared with baseline (Day 1) at the specified assessment time. Arthritis nonresponder: For RA, PsA, AS, or nrAxSpA, a participant who did not fulfill the definition of arthritis responder at the specified assessment timepoint. PhGADA: Physician measured the participant's disease severity on a VAS ranged from 0 (no disease)-100 (worst disease) mm. The normal range for sperm total motility is ≥40%.

Time frame: Baseline, Week 26

Change From Baseline in Total Sperm Count at Week 13

The normal range for total sperm count is ≥ 39 million sperms/ejaculate.

Time frame: Baseline, Week 13

Change From Baseline in Total Sperm Count at Week 26

Arthritis responder: For RA, PsA, AS, and nrAxSpA, a participant with an improvement in the PhGADA of at least 20% compared with baseline (Day 1) at the specified assessment time. Arthritis nonresponder: For RA, PsA, AS, or nrAxSpA, a participant who did not fulfill the definition of arthritis responder at the specified assessment timepoint. PhGADA: Physician measured the participant's disease severity on a VAS ranged from 0 (no disease)-100 (worst disease) mm. The normal range for total sperm count is ≥ 39 million sperms/ejaculate.

Time frame: Baseline, Week 26

Change From Baseline in Sperm Concentration at Week 13

The normal range for sperm concentration is ≥15 million sperms/mL.

Time frame: Baseline, Week 13

Change From Baseline in Sperm Concentration at Week 26

Arthritis responder: For RA, PsA, AS, and nrAxSpA, a participant with an improvement in the PhGADA of at least 20% compared with baseline (Day 1) at the specified assessment time. Arthritis nonresponder: For RA, PsA, AS, or nrAxSpA, a participant who did not fulfill the definition of arthritis responder at the specified assessment timepoint. PhGADA: Physician measured the participant's disease severity on a VAS ranged from 0 (no disease)-100 (worst disease) mm. The normal range for sperm concentration is ≥15 million sperms/mL.

Time frame: Baseline, Week 26

Change From Baseline in Ejaculate Volume at Week 13

The normal range for ejaculate volume is ≥1.5 mL.

Time frame: Baseline, Week 13

Change From Baseline in Ejaculate Volume at Week 26

Arthritis responder: For RA, PsA, AS, and nrAxSpA, a participant with an improvement in the PhGADA of at least 20% compared with baseline (Day 1) at the specified assessment time. Arthritis nonresponder: For RA, PsA, AS, or nrAxSpA, a participant who did not fulfill the definition of arthritis responder at the specified assessment timepoint. PhGADA: Physician measured the participant's disease severity on a VAS ranged from 0 (no disease)-100 (worst disease) mm. The normal range for ejaculate volume is ≥1.5 mL.

Time frame: Baseline, Week 26

Change From Baseline in Percent Normal Sperm Morphology at Week 13

The normal range for percent normal sperm morphology is ≥30% normal sperms.

Time frame: Baseline, Week 13

Change From Baseline in Percent Normal Sperm Morphology at Week 26

Arthritis responder: For RA, PsA, AS, and nrAxSpA, a participant with an improvement in the PhGADA of at least 20% compared with baseline (Day 1) at the specified assessment time. Arthritis nonresponder: For RA, PsA, AS, or nrAxSpA, a participant who did not fulfill the definition of arthritis responder at the specified assessment timepoint. PhGADA: Physician measured the participant's disease severity on a VAS ranged from 0 (no disease)-100 (worst disease) mm. The normal range for percent normal sperm morphology is ≥30% normal sperms.

Time frame: Baseline, Week 26