P0268A COMPARATIVE STUDY OF CYCLOPHOSPHAMIDE, THALIDOMIDE AND DEXAMETHASONE (CTD) VERSUS BORTEZOMIB AND DEXAMETHASONE (BDEX) IN AL AMYLOIDOSIS: A REAL-WORD STUDY IN CHINESE PATIENTS

Abstract

Abstract Background and Aims Amyloid light-chain (AL) amyloidosis is a plasma cell dyscrasia characterized by the deposition of misfolded immunoglobulin light chains. The prognosis of AL patients is poor. About 70% of patients have renal involvement and one third of patients would progress to dialysis. Cyclophosphamide, thalidomide and dexamethasone (CTD) and bortezomib and dexamethasone (BDex) have shown great efficacy in patients with AL amyloidosis, especially in Chinese patients. But which option is more suitable for Chinese patients is unclear. Method We retrospectively evaluated 81 AL patients who received CTD (n = 42) or BDex (n = 39) and used Mayo stage 2012 to match 26 pairs of patients. Results In the whole cohort, the overall hematologic responses were 86% vs 91% in the CTD and BDex groups, including a complete response of 56% vs 71%, higher than most of the previously reported chemotherapies. One- and two-year overall survival (OS) was 90.2% and 81.7% with CTD regimen, and 87.6% and 82.7% with BDex regimen. After matching by Mayo stage 2012, BDex regimen showed the advantage in the depth and speed of hematologic response over CTD regimen, but there were no statistically significant differences in OS both based on the ITT analysis (P = 0.24) and 6-month landmark analysis (P = 0.48). Cardiac response was similar, while there was a trend for higher renal response in patients treated with BDex (68% vs 44%, P = 0.09). Additionally, we found that if the patients were limited to Mayo stage III or worse, BDex regimen was associated with improved survival (P = 0.009). Overall toxicities were manageable in both regimens. Severe hematologic toxicities and diarrhea should get more attention in patients treated with BDex. Conclusion This is the first comparison of BDex versus CTD in patients with AL amyloidosis. These results indicated that CTD and BDex regimens can be active and safe chemotherapy for Chinese patients, but BDex regimen is superior to CTD in achieving more rapidly and deeper clonal response, as well as in improving OS in selected patients.This conclusion is significant because we confirmed BDex regimen may be an optimal option in treating Chinese patients with AL amyloidosis. The definite advantages on long-term prognosis need to be verified in the further studies.