Sequential response-driven bortezomib-based therapy followed by autologous stem cell transplant in AL amyloidosis

Abstract

Autologous stem cell transplant (ASCT) is highly effective in selected patients with light chain (AL) amyloidosis. Bortezomib, preceding or following ASCT, improves responses. Satisfactory responses, including at least a partial response, very good partial response (VGPR) with organ response, or complete response, can be observed after induction therapy alone. We report 139 patients treated upfront with cyclophosphamide/bortezomib/dexamethasone (CyBorD), followed by ASCT only if response was unsatisfactory. Only 1 treatment-related death was observed. After CyBorD, hematologic response (HR) rate was 68% (VGPR or better, 51%), with 45% satisfactory responses. Transplant was performed in 55 (40%) subjects and resulted in an 80% HR rate (65% ≥ VGPR). Five-year survival was 86% and 84% in patients treated with ASCT or CyBorD alone, respectively (P = .438). Also, 6- and 12- month landmark analyses did not show differences in survival. Duration of response was not different in the 2 groups (60 vs 49 months; P = .670). Twenty-one (15%) patients with an unsatisfactory response to CyBorD could not undergo ASCT because of ineligibility or refusal; instead, they received rescue chemotherapy, with HR in 38% of cases and 51% 5-year survival. This sequential response-driven approach, offering ASCT to patients who do not attain satisfactory response to upfront CyBorD, is very safe and effective in AL amyloidosis.

Graphical abstract

Figure 1.

OS and TNTD in patients treated with CyBorD and ASCT and in those who received CyBorD alone. (A) OS in patients treated with CyBorD and ASCT. (B) OS in patients with a satisfactory response to CyBorD. Six-month landmark plotted OS in patients treated with CyBorD (C) or with CyBorD and ASCT (D) who achieved a VGPR or better. Six-month landmark plotted TNTD in patients who received only CyBorD (E) or CyBorD and ASCT (F).