Systemic Light Chain Amyloidosis

This is a prospective, single-arm, single-center clinical study designed to evaluate the efficacy and safety of low-dose BCMA/CD3 bispecific antibody (CM336) in patients newly diagnosed with systemic light chain (AL) amyloidosis.

Systemic light chain amyloidosis (AL amyloidosis) is the most common type of systemic amyloidosis, with diverse clinical manifestations and difficulties in diagnosis and treatment. AL amyloidosis may involve multiple organs; the kidney and heart are the most commonly involved organs. The treatment goal is to reduce monoclonal immunoglobulin light-chain levels, prevent further amyloid deposition in important organs, and alleviate or reverse organ dysfunction caused by amyloid deposition. The principal approach to achieve this goal is to eliminate the plasma-cell or B-cell clones producing abnormal light chains. For patients with relapsed/refractory AL amyloidosis, the protocol states that there is currently no suitable treatment method and that participation in clinical trials is recommended. This study evaluates targeted BCMA autologous CART cell injection in participants with relapsed/refractory light chain amyloidosis. The main purpose is to evaluate safety, preliminarily verify efficacy, and explore in vivo pharmacokinetics, pharmacodynamics, immunogenicity and related characteristics after infusion.

This study is a clinical trial aimed at the marketing of TQB2934 for injection. The project plans to enroll 70 subjects, including 13-21 subjects in Phase Ib, to evaluate the safety and preliminary efficacy, pharmacokinetic (PK) characteristics, immunogenicity, and pharmacodynamic (PD) of TQB2934 for injection in subjects with systemic light chain amyloidosis, and to determine the recommended Phase II dose (RP2D). The Phase II plan involves enrolling 49 subjects, aiming to demonstrate that in adult subjects with relapsed/refractory systemic light chain amyloidosis who have previously received treatment with daratumumab and bortezomib, TQB2934 for injection significantly improves the hematological complete response (CR) rate compared to historical controls. The primary endpoint is the optimal hematological CR rate.

Study Purpose and Principle: Amyloidosis is a group of diseases characterized by the deposition of amyloid proteins in tissues and organs throughout the body, with common affected organs including kidneys, heart, nervous system, gastrointestinal tract, and liver. Nowadays, nearly 40 different proteins have been found to form amyloid fibrils in body, among which Systemic Light Chain (AL) Amyloidosis is the most common type of systemic amyloidosis. AL amyloidosis is a plasma cell disorder, with its precursor protein originating from free light chains produced by abnormal plasma cell clones, which form amyloid substances that deposit in tissues and organs causing lesions. In terms of incidence, the incidence of AL amyloidosis is 8-10 cases per million person-years in the United States and is considered a rare disease in our country. AL amyloidosis has an insidious onset, diverse clinical manifestations, and is prone to misdiagnosis and missed diagnosis in clinical practice. The prognosis also has strong heterogeneity and is closely related to the extent of organ involvement at the time of diagnosis. In the past, the incidence of eye involvement in systemic AL amyloidosis patients was low, with various manifestations, only reported as case reports, and not regularly followed up with systemic treatment. Based on this, this project aims to assess the involvement of eyes and its appendages in patients with different stages of systemic light chain amyloidosis, with the goal of clarifying the ocular manifestations of this systemic disease and exploring early diagnostic indicators for the eye. Primary Objective: To assess the involvement of the anterior segment of the eye, as well as the extraocular soft tissues and muscles, in patients with systemic light chain amyloidosis. Secondary Objective: To assess the neuro-ophthalmic manifestations and changes in retinal choroidal blood flow in patients with systemic light chain amyloidosis. Study Design: Observational study. Study Population and Expected Enrollment: 80 patients with systemic light chain amyloidosis, 50 normal controls. Study Duration: Six months of follow-up after the last subject is diagnosed and enrolled. Intervention: Experimental Group: Patients with systemic light chain amyloidosis; Control Group: Subjects without systemic diseases.