A Study of Telitacicept for the Treatment of Moderately to Severely Active Systemic Lupus Erythematosus (REMESLE-1)

A Multicenter, Randomized, Double-Blind, Placebo-Controlled, 2-Stage Trial to Evaluate Efficacy and Safety of Telitacicept Compared to Placebo in Patients With Moderately to Severely Active Systemic Lupus Erythematosus (REMESLE-1)

The purpose of this study is to evaluate the efficacy and safety of telitacicept in the treatment of moderately to severely active SLE.

Systemic Lupus Erythematosus (SLE) is a chronic autoimmune disease with heterogeneous manifestations and disease course. Despite advances in medical care, there are still significant unmet needs in SLE with diminished health-related quality of life (HRQoL), persistent disease activity, disease flares, intolerance to standard of care (SoC) therapies, and development of organ damage and co-morbidities.

Telitacicept is a fully human TACI-Fc fusion protein that targets B lymphocyte stimulator (BLyS) and a proliferating-inducing ligand (APRIL). Blocking the interaction of BLyS and APRIL with their cell membrane receptors (TACI, B-cell maturation antigen (BCMA), and B-cell activating factor receptor (BAFF-R)) would inhibit B cell proliferation and maturation, suppresses immune responses, and may alleviate autoimmune symptoms.

This Phase 3 study is a 2-stage study to evaluate the efficacy and safety of telitacicept compared to placebo in patients with moderately to severely active SLE while receiving SoC treatment in a global patient population with active SLE disease.

• Stage 1: a study to evaluate the efficacy, safety, pharmacokinetics (PK) and PD of two treatment arms of telitacicept compared to placebo in patients with moderately to severely active SLE while receiving SoC treatment.
• Stage 2: a multicenter, randomized, double-blind, placebo-controlled study to evaluate the efficacy and safety of telitacicept added to SoC compared to placebo with SoC therapy in patients with moderately to severely active SLE.

Inclusion Criteria:

1. Age 12-70 years at screening.

2. Has a diagnosis of SLE for at least 6 months prior to the screening visit.

3. Meets the 2019 EULAR/ACR Classification criteria for SLE.

4. Moderately to severely active SLE defined by the following:

   1. SELENA SLEDAI total score ≥6 points with clinical SLEDAI score ≥4 points at screening;
   2. BILAG organ system scores of at least 1A or 2B at screening.

5. Clinical SLEDAI score of ≥4 at Day 0 prior to randomization.

6. At least one positive serologic parameter within the screening period.

7. Currently receiving at least one of the SOC SLE medications: oral corticosteroid, antimalarial and/or immunosuppressive agent.

Exclusion Criteria:

1. Active lupus nephritis undergoing induction therapy or unstable renal diseases within 12 weeks prior to screening.
2. Active or unstable neuropsychiatric SLE.
3. Autoimmune or rheumatic disease other than SLE