Outcomes of BTD vs. BCD as initial treatment of renal amyloid light-chain amyloidosis: a retrospective cohort study in China.

Objectives: To compare the efficacy and safety of bortezomib with thalidomide and dexamethasone (BTD) and bortezomib with cyclophosphamide and dexamethasone (BCD) as the initial treatment for renal amyloid light chain (AL) amyloidosis in Chinese cohort.

Methods: A cohort of 174 patients with AL amyloidosis was studied in Guangdong Provincial People's Hospital from January 2008 to August 2023. Propensity-score matching cases were applied to assess the outcomes of patients treated with BTD and BCD regimen. Primary outcomes were patients achieving hematologic response and organ responses, and the secondary endpoints were patients progressing to end-stage renal disease or all-cause death.

Results: 44 Patients were included. The hematologic complete response rate (CR) in the BTD group was comparable between the groups of BTD group and BCD. However, the time to achieve hematologic CR was significantly shorter in the BTD group compared to the BCD group (4.97 vs. 7.71 mon, p = 0.010). Furthermore, when reaching hematologic response, the cumulative dose of bortezomib that standardized by body surface area (BSA) was lower in BTD group than in the BCD group (10.4 vs. 15.6 mg/m², p = 0.013). There was no significant difference of renal and cardiac response between groups. However, post-treatment proteinuria levels after treatment were significantly lower in the BTD group compared to those in the BCD group (747 mg/24h vs. 2928 mg/24h, p = 0.048).

Conclusions: Compared to BCD regimen for renal AL amyloidosis, initial treatment with BTD regimen demonstrated similar rates of hematologic CR but showed superior reduction in proteinuria, reduced cumulative dose of bortezomib and faster time-to-response.