PBSC Mobilization for Auto-HSCT in Myeloma: Growth Factors Vs Growth Factors + Chemotherapy

Background: Peripheral blood hematopoietic stem cell mobilization for autologous hematopoietic stem cell transplantation (auto-HSCT) in multiple myeloma (MM) can be achieved with either growth factors (GF) alone (filgrastim +/- plerixafor), or with chemotherapy (GF + chemo). When utilized, the chemotherapy regimens include single-agent cyclophosphamide (Cy), or combination regimens, including cyclophosphamide, vincristine or bortezomib, doxorubicin, dexamethasone (CVAD/CBAD) at our center. The optimal mobilization strategy, however, has yet to be established. Methods: In this single center retrospective analysis, we identified 1,006 patients who received auto-HCT for MM between 2009 and 2015. This time-period was chosen to include patients who received auto-HCT after the availability of plerixafor. Patients were divided into 4 groups: G (filgrastim alone), G+P (filgrastim + plerixafor), Cy, and CVAD/CBAD. Plerixafor was mainly used “just-in-time”, and not as planned therapy in accordance with our Departmental guidelines. Primary endpoints were CD34+ cell dose/kg collected, days to collect the target CD34+ cell dose, time to neutrophil engraftment (first of three consecutive days of peripheral blood neutrophil count of >500 x 106/L), packed red blood cell (PBRC) and platelet transfusion requirement, duration of hospitalization, progression-free survival (PFS), and overall survival (OS). Results: Patient characteristics are summarized in Table 1. There were 654 patients mobilized with G, 203 with G + P, 80 with Cy, and 69 with CVAD/CBAD. Patients mobilized with CVAD/CBAD were younger compared to the other three groups, were less likely to have achieved VGPR to induction, and more likely to have received a more intense preparative regimen (Table 1). Patients who received G alone, G+P, Cy, and CVAD/CBAD collected a median of 4.1 (0.7-12.2), 4.0 (1.8-11.1), 5.2 (2.2-19.2), and 5.6 (2.5-26.6) x106 CD34+ cells/kg [p Conclusion: Approximately 85% of MM patients underwent PBSC mobilization with GF only (G or G+P). GF + chemo (Cy, CVAD/CBAD) was primarily used in patients with suboptimal response to induction, and allowed successful PBSC collection in this high-risk group. GF + chemo-based mobilization was associated with a higher CD34+ cell dose collection, without improving the time to neutrophil or platelet engraftment, PRBC or platelet transfusion requirement, or the duration of hospitalization. Download : Download high-res image (265KB) Download : Download full-size image Disclosures Bashir: Purdue: Other: Advisory Board; StemLine: Research Funding; Acrotech: Research Funding; Takeda: Other: Advisory Board, Research Funding; Celgene: Research Funding; Amgen: Other: Advisory Board; KITE: Other: Advisory Board. Nieto: Secura Bio: Other: Grant Support; Astra Zeneca: Other: Grant Support; Novartis: Other: Grant Support; Affimed: Consultancy, Other: Grant Support. Hosing: NKARTA Inc.: Consultancy. Popat: Bayer: Research Funding; Novartis: Research Funding. Lee: Sanofi: Consultancy; GlaxoSmithKline: Consultancy, Research Funding; Genentech: Consultancy; Amgen: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Genentech: Consultancy; Regeneron: Research Funding; Daiichi Sankyo: Research Funding; Takeda: Consultancy, Research Funding; Janssen: Consultancy, Research Funding. Patel: Bristol Myers Squibb: Consultancy, Research Funding; Oncopeptides: Consultancy; Poseida: Research Funding; Janssen: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Cellectis: Research Funding; Precision Biosciences: Research Funding; Takeda: Consultancy, Research Funding; Nektar: Consultancy, Research Funding. Manasanch: Merck: Research Funding; Novartis: Research Funding; Quest Diagnostics: Research Funding; Adaptive Biotechnologies: Honoraria; GSK: Honoraria; Sanofi: Honoraria; BMS: Honoraria; Takeda: Honoraria; JW Pharma: Research Funding; Sanofi: Research Funding. Thomas: BMS: Research Funding; Ascentage: Membership on an entity’s Board of Directors or advisory committees, Research Funding; X4 Pharma: Research Funding; Xencor: Research Funding; Pharmacyclics: Other: Advisory Boards; Genentech: Research Funding. Kaufman: Karyopharm: Honoraria; Bristol Myers Squibb: Research Funding; Janssen: Research Funding. Orlowski: Amgen, Inc., AstraZeneca, BMS, Celgene, EcoR1 Capital LLC, Forma Therapeutics, Genzyme, GSK Biologicals, Ionis Pharmaceuticals, Inc., Janssen Biotech, Juno Therapeutics, Kite Pharma, Legend Biotech USA, Molecular Partners, Regeneron Pharmaceuticals, Inc.,: Honoraria, Membership on an entity’s Board of Directors or advisory committees; Laboratory research funding from BioTheryX, and clinical research funding from CARsgen Therapeutics, Celgene, Exelixis, Janssen Biotech, Sanofi-Aventis, Takeda Pharmaceuticals North America, Inc.: Research Funding; Founder of Asylia Therapeutics, Inc., with associated patents and an equity interest, though this technology does not bear on the current submission.: Current equity holder in private company, Patents & Royalties; Sanofi-Aventis, Servier, Takeda Pharmaceuticals North America, Inc.: Honoraria, Membership on an entity’s Board of Directors or advisory committees; STATinMED Research: Consultancy. Champlin: Actinium: Consultancy; Johnson and Johnson: Consultancy; Omeros: Consultancy; Cytonus: Consultancy; DKMS America: Membership on an entity’s Board of Directors or advisory committees; Genzyme: Speakers Bureau; Takeda: Patents & Royalties. Qazilbash: Bioclinica: Consultancy; Amgen: Research Funding; Janssen: Research Funding; Angiocrine: Research Funding; Bioline: Research Funding.