A Phase 1 Study of QLS2416 Injection in Participants With Autoimmune Diseases

This is a Phase 1, multicenter, open-label, dose-escalation and dose-expansion study of QLS2416 injection in participants with autoimmune diseases. The study consists of two parts: 1. Dose Escalation Part: * Up to 42 participants with active SLE, RA, or pSS will be enrolled across up to 7 dose cohorts (0.025 mg to 6.0 mg). * A Safety Monitoring Committee (SMC) will review safety, PK, pharmacodynamic (PD), and efficacy data before dose escalation. 2. Dose Expansion Part: * Approximately 24 participants with SLE and 10 participants with dcSSc will be enrolled * Multiple dosing may be administered based on emerging safety, efficacy, and PK data. QLS2416 is a novel biologic agent being developed for the treatment of B-cell-mediated autoimmune diseases. The study will characterize the safety, tolerability, PK, PD, immunogenicity, and preliminary efficacy of QLS2416 in participants with active autoimmune diseases who have had inadequate response or intolerance to standard therapies.