A Case Report of a 58-Year-Old Woman with a Diagnosis of High-Risk Myeloma Refractory to Multiple Line of Therapy and Treated with Selinexor, Bortezomib, and Dexamethasone Prior to Allogeneic Stem Cell Transplantation.

BACKGROUND Approximately 10% to 15% of patients with multiple myeloma (MM) are diagnosed with high-risk disease and have poor prognosis. Clinical trial data supports the combined use of selinexor, bortezomib, and dexamethasone (XVd) for treatment of patients with MM who have received at least 1 prior therapy. Information on the efficacy of XVd and of subsequent allogeneic stem cell transplantation (SCT) in heavily pretreated patients with high-risk MM is limited. CASE REPORT We present a case of a 58-year-old woman with high-risk MM (revised International Staging System Stage III; serum ß₂-microglobulin; 8.0 mg/L; and presence of del[17p]) who had received 8 prior treatment lines, and whose disease was refractory to ixazomib, bortezomib, and all immunomodulatory agents. Before initiating XVd (once weekly 1.3 mg/m² bortezomib subcutaneously, 80 mg selinexor per os, and 40 mg dexamethasone per os), the patient had severely hypoplastic bone marrow and was transfusion dependent. After 1 cycle of XVd, she achieved a partial response, and after 4 cycles, a very good partial response (VGPR). No adverse reactions to selinexor were observed. Because of the VGPR, a haploidentical transplant was planned. At posttransplant week 4, the patient had become transfusion independent. She remained relapse-free for 13 months after initiating XVd. Maintenance treatment with lenalidomide was initiated, and following receipt of donor lymphocyte infusions due to loss of donor chimerism, the patient's light chain levels improved. CONCLUSIONS This report presents the cytogenetics and management of a heavily pretreated patient with high-risk MM treated with SVd followed by SCT.