Early Clinical Study of the Safety, Tolerability, Pharmacokinetics, and Effectiveness of STR-P005

This is a single-center, single-arm, open-label, investigator-initiated early exploratory clinical trial designed to evaluate the safety and efficacy of STR-P005 in participants with relapsed/refractory autoimmune diseases. The study will employ a traditional "3+3" dose-escalation design, with 3 dose groups: XXmg/kg, XXmg/kg, XXmg/kg. Dose Group 1 is the starting dose. This group includes two cohorts, A and B, to optimize the dosing frequency of STR-P005. Cohort A will receive doses Q3D (once every 3 days) on Days 1, 4, 7 (3 doses per cycle), for up to 2 cycles. Cohort B will receive doses Q4D (once every 4 days) on Days 1, 4 (2 doses per cycle), for up to 2 cycles. Based on preliminary safety, efficacy, PK/PD data from Cohorts 1A and 1B, the superior regimen will be selected for escalation to Dose Groups 2 and 3. If no optimal dose is identified after escalating through the 3 dose groups, additional higher doses may be explored after SRC discussion based on all accumulated preliminary safety, efficacy, and PK/PD data to further evaluate the safety and efficacy of STR-P005.