Abstract 786P
Background
Autologous stem cell transplantation (ASCT) is crucial for newly diagnosed multiple myeloma (MM) patients, requiring effective mobilization. New therapeutic agents like lenalidomide and daratumumab have improved response rates but previous studies have suggested they have led to more difficult mobilization. This study examines the impact of induction regimens on stem cell mobilization, collection, and ASCT success rates.
Methods
We retrospectively reviewed MM patients undergoing ASCT at Seoul National University Hospital from January 2020 to December 2023. A total of 231 patients were categorized into three groups based on their induction regimens: Bortezomib-thalidomide-dexamethasone (VTD, N=117); Bortezomib-lenalidomide-dexamethasone (VRD, N=57); Daratumumab-VTD (DVTD, N=57). One hundred ninety-seven patients were mobilized with subcutaneous G-CSF at 10 μg/kg for 4 days. Thirty-four patients initially underwent chemomobilization (3 with DCEP regimen, 31 with cyclophosphamide). Plerixafor was administered as an additional mobilization agent if needed.
Results
There were no differences in the baseline characteristics including age at diagnosis, sex, and ISS stage between the 3 groups. Initial chemomobilization was most common in VTD patients (20%), followed by VRD (12%) and DVTD patients (5%) [p=0.024]. CD34 cell yields (x10⁶/kg) were highest in the VTD group (6.4 ± 3.8), compared to VRD (4.3 ± 3.7) and DVTD group (4.4 ± 2.8) [p<0.001]. Second mobilization was most common in the VRD group (40.4%), compared to DVTD (22.8%) and VTD group (17.2%) [p=0.01]. Plerixafor use was highest in the VRD group (40.4%), compared to DVTD (22.8%) and VTD group (12.8%) [p<0.001]. Total collection period, infused CD34 cells, and time to engraftment were not significantly different. [p=0.60, p=0.16, p=0.44, respectively].
Conclusions
Lenalidomide complicates stem cell collection, making it essential to collect PBSCs promptly without excessive induction cycles. Interestingly, DVTD regimen did not negatively affect mobilization compared to VRD.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.