A study evaluating the safety, tolerability, and efficacy of GLPG5101 in adults with treatment-refractory active systemic lupus erythematosus

Prior treatment

• Subjects with a history or current diagnosis of catastrophic or severe antiphospholipid syndrome within 1 year prior to signing the ICF are excluded. This includes subjects with a serious thrombotic event (e.g. pulmonary embolism, stroke, deep vein thrombosis) or unexplained pregnancy loss within 1 year before the screening visit or history of 3 or more unexplained consecutive pregnancy losses. Subjects with antiphospholipid syndrome adequately controlled by anticoagulant therapy for at least 3 months should not be excluded.

Other illness

• Subjects with active central nervous system (CNS) lupus, active or unstable SLE neuropsychiatric manifestations, psychiatric patients with antinuclear antibodies, subjects with drug-induced SLE, or subjects with a significant non-SLE vasculitis or skin conditions.
• Subject with organ specific (kidney, heart, lung, gastrointestinal, and/or liver) Systemic Lupus International Collaborating Clinics (SLICC) criteria >=2 in active/qualifying organs.
• Subjects with a hepatitis B virus (HBV) infection confirmed by positive HBV surface antigen (HBsAg) OR with isolated positive anti-HBV core antibody (HBcAb) and positive HBV DNA (PCR).
• Subject with a hepatitis C virus (HCV) infection confirmed by positive HCV antibody (Ab) and positive HCV RNA (PCR).
• Subject has a history of or a current immunosuppressive condition, other than SLE (e.g. human immunodeficiency virus [HIV] infection).

• Subject must be able and willing to comply with the CSP requirements and must sign and date the ICF as approved by the Independent Ethics Committee (IEC)/Institutional Review Board (IRB), prior to any screening evaluations.
• Subject must have a body mass index (BMI) between 18 and 32 kg/m2, inclusive at screening.<
• Subject must be able and willing to comply with restrictions on prior and concomitant medications and CS tapering
• Subject with documented diagnosis of SLE as defined by the 2019 European Alliance of Associations for Rheumatology (EULAR)/American College of Rheumatology (ACR) (Aringer et al., 2019) classification criteria with a disease diagnosed >=24 weeks before the screening visit.
• Active SLE with major inner organ involvement (i.e. kidney, heart, lung, gastrointestinal tract, liver, or immune cytopenia) as defined by >=1 BILAG A; OR >=2 BILAG B in at least 1 major inner organ (i.e. kidney, heart, lung, gastrointestinal tract, liver or immune cytopenia).
• Subject with serologically active disease as indicated by positive anti-dsDNA, and/or anti- Sm, and/or anti-nucleosome antibodies as determined by the central laboratory.