Contributions
Abstract: EP356
Type: E-Poster Presentation
Session title: Acute lymphoblastic leukemia - Clinical
Background
Compared with HLA-matched sibling donor (MSD) transplantation, whether haploidentical donor (HID) transplantation has superior graft-versus-leukemia (GVL) effect for Philadelphia-negative (Ph-) high-risk B-cell acute lymphoblastic leukemia (B-ALL) remains unclear.
Aims
This study aimed to compare the GVL effect between HID and MSD for Ph- high-risk B-ALL.
Methods
This study population came from two prospective multicenter trials (NCT01883180, NCT02673008). Immunosuppressant withdrawal, prophylactic or preemptive donor lymphocyte infusion (DLI) was administered in patients without active graft-versus-host disease (GVHD) for preventing relapse. All patients with measurable residual disease positive post-transplantation (post-MRD+) or non-remission pre-transplantation received prophylactic/ preemptive interventions. The primary endpoint was the incidence of post-MRD+.
Results
A total of 335 patients with Ph- high-risk B-ALL were enrolled, including 145 in HID and 190 in MSD group. The 3-year cumulative incidence of post-MRD+ was 27.2% (95% CI: 20.2-34.7%) and 42.6% (35.5-49.6%) in the HID and MSD groups (P=0.003). A total of 156 patients received DLI, including 60 (41.4%) in HID and 96 (50.5%) in MSD group (P=0.096). The 3-year relapse rate was 18.6% (95% CI: 12.7-25.4%) and 25.9% (19.9-32.3%; P=0.116) in the two groups. The 3-year overall survival was 67.4% (95% CI: 59.1-74.4%) and 61.6% (54.2-68.1%; P=0.382), leukemia-free survival was 63.4% (95% CI: 55.0-70.7%) and 58.2% (50.8-64.9%; P=0.429), and GVHD-free/relapse-free survival was 51.7% (95% CI: 43.3-59.5%) and 37.8% (30.9-44.6%; P=0.041), respectively, in the HID and MSD groups.
Conclusion
HID transplantation has lower incidence of post-MRD+ than MSD transplantation, suggesting HID might have superior GVL effect than MSD for Ph- high-risk B-ALL patients.
Keyword(s): Acute lymphoblastic leukemia, Graft-versus-leukemia, Haploidentical stem cell transplantation, MRD
Abstract: EP356
Type: E-Poster Presentation
Session title: Acute lymphoblastic leukemia - Clinical
Background
Compared with HLA-matched sibling donor (MSD) transplantation, whether haploidentical donor (HID) transplantation has superior graft-versus-leukemia (GVL) effect for Philadelphia-negative (Ph-) high-risk B-cell acute lymphoblastic leukemia (B-ALL) remains unclear.
Aims
This study aimed to compare the GVL effect between HID and MSD for Ph- high-risk B-ALL.
Methods
This study population came from two prospective multicenter trials (NCT01883180, NCT02673008). Immunosuppressant withdrawal, prophylactic or preemptive donor lymphocyte infusion (DLI) was administered in patients without active graft-versus-host disease (GVHD) for preventing relapse. All patients with measurable residual disease positive post-transplantation (post-MRD+) or non-remission pre-transplantation received prophylactic/ preemptive interventions. The primary endpoint was the incidence of post-MRD+.
Results
A total of 335 patients with Ph- high-risk B-ALL were enrolled, including 145 in HID and 190 in MSD group. The 3-year cumulative incidence of post-MRD+ was 27.2% (95% CI: 20.2-34.7%) and 42.6% (35.5-49.6%) in the HID and MSD groups (P=0.003). A total of 156 patients received DLI, including 60 (41.4%) in HID and 96 (50.5%) in MSD group (P=0.096). The 3-year relapse rate was 18.6% (95% CI: 12.7-25.4%) and 25.9% (19.9-32.3%; P=0.116) in the two groups. The 3-year overall survival was 67.4% (95% CI: 59.1-74.4%) and 61.6% (54.2-68.1%; P=0.382), leukemia-free survival was 63.4% (95% CI: 55.0-70.7%) and 58.2% (50.8-64.9%; P=0.429), and GVHD-free/relapse-free survival was 51.7% (95% CI: 43.3-59.5%) and 37.8% (30.9-44.6%; P=0.041), respectively, in the HID and MSD groups.
Conclusion
HID transplantation has lower incidence of post-MRD+ than MSD transplantation, suggesting HID might have superior GVL effect than MSD for Ph- high-risk B-ALL patients.
Keyword(s): Acute lymphoblastic leukemia, Graft-versus-leukemia, Haploidentical stem cell transplantation, MRD