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4979 Allogeneic Hematopoietic Stem Cell Transplantation in Adolescents and Young Adults with Acute Lymphoblastic Leukemia – Retrospective Dual-Center Study

Program: Oral and Poster Abstracts
Session: 732. Allogeneic Transplantation: Disease Response and Comparative Treatment Studies: Poster III
Hematology Disease Topics & Pathways:
Research, Lymphoid Leukemias, ALL, Biological therapies, Clinical Research, Diseases, Therapies, Lymphoid Malignancies, Transplantation
Monday, December 11, 2023, 6:00 PM-8:00 PM

Oren Pasvolsky, MD1*, Shai Shimony, MD2*, Rima M. Saliba, PhD1*, Celina Ledesma1*, Gabriela Rondon, MD3, Priti Tewari, MD4*, Dristhi Ragoonanan, MBBS5, Nicholas J. Short, MD6, Elias Jabbour7, Mahasweta Gooptu, MD8, Vincent T. Ho, MD9*, Robert J. Soiffer, MD10, Joseph Antin, MD10*, John Koreth, MD, MBBS, PhD, DPhil10, Corey Cutler10, Jonathan Paolino, MD11, Christine Duncan, MD12, Leslie E. Lehmann13, Daniel J. DeAngelo, MD14, Hagop M. Kantarjian, MD6, Richard E. Champlin, MD4, Elizabeth J. Shpall, MD1, Marlise R. Luskin, MD14 and Partow Kebriaei, MD1

1Department of Stem Cell Transplantation and Cellular Therapy, The University of Texas MD Anderson Cancer Center, Houston, TX
2Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA
3University f Texas MD Anderson Cancer Center, Houston, TX
4MD Anderson Cancer Center, Houston, TX
5University of Texas MD Anderson Cancer Center, Houston, TX
6Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX
7University of Texas M.D. Anderson Cancer Ctr., Houston, TX
8Medical Oncology, Dana-Farber Cancer Institute, Brookline, MA
9Stem Cell Transplantation, Harvard Medical School, Boston, MA
10Dana-Farber Cancer Institute, Boston, MA
11Dana Farber Cancer Institute, Boston, MA
12Division of Pediatric Hematology/Oncology, Boston Children’s Hospital, Boston, MA
13Dana-Farber Cancer Institute, Inc., Boston, MA
14Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA

Background: Adolescents and young adults (AYAs) with acute lymphoblastic leukemia (ALL) are treated with various chemotherapy regimens. Some patients undergo allogeneic hematopoietic stem cell transplantation (HCT) due to high-risk genetic characteristics, chemo-resistant disease (failure to achieve timely measurable residual disease (MRD) negative remissions, or relapse or refractory disease. There is paucity of data on outcomes of AYA ALL patients receiving HCT.

Methods: We performed a dual-center analysis of data from MD Anderson Cancer Center (MDACC) and Dana-Farber Cancer Institute (DFCI) to evaluate outcomes of AYA patients who received HCT for Philadelphia-negative (Phneg) ALL and examined variables that might have an impact on these outcomes. We included all patients who received their first HCT between the ages of 15-40 years between the years 2010-2022. MRD status was evaluated using flow cytometry with a sensitivity of 0.01%. Acute and chronic graft versus host disease (GvHD) were classified according to consensus criteria. The primary endpoint was overall survival (OS), and secondary endpoints included progression rate and non-relapse mortality (NRM). Cox proportional hazards regression analysis was used to evaluate predictors of OS, and Fine and Gray regression for predictors of relapse and NRM. Competing risks were accounted for in analyses pertaining to progression and NRM.

Results: A total of 376 Phneg ALL AYA patients were included in the analysis, 247 from MDACC and 129 from DFCI. The median age at transplant was 25 (range 15-40) years, 39 patients (10%) were aged ≤18 years at time of HCT and 251 (67%) were males. The majority had B-ALL (n=282, 75%), 42 (11%) had complex karyotype and 28 patients (7%) had translocation (4:11). Most patients received either pediatric-inspired (48%) or hyper- cyclophosphamide, vincristine sulfate, doxorubicin, dexamethasone (CVAD) based (42%) frontline induction regimens, and the median time from diagnosis to HCT was 11 (range 2-283) months. At transplant, most patients were in CR1 or CR2 (44% each); 63% of patients achieved MRD negativity prior to HCT. Most patients received an HCT from a matched unrelated donor (MUD) (33%) or a matched sibling donor (MSD) (32%), and most patients received myeloablative conditioning (MAC) (79%) (Table 1).

The cumulative incidence of grade 2-4 acute GvHD and grade 3-4 acute GvHD at 6 months was 37% (95% CI 33%-42%) and 13% (95% CI 10%-17%), respectively. The cumulative incidence of chronic GvHD at 3 years was 28% (95% CI 23%-33%), with most patients experiencing either mild (39%) or moderate (36%) chronic GvHD, and 25% had severe chronic GvHD.

For patients transplanted in CR1, CR2 and CR3/PD the estimated 3-year OS was 69% (95% CI 61%-77%), 53% (95% CI 44%-61%) and 29% (95% CI 16%-43%), respectively; the 3-year NRM rate was 9% (95% CI 5%-15%), 18% (95% CI 13%-25%) and 27% (95% CI 16%-43%), respectively; and the 3-year progression rate was 27% (95% CI 20%-35%), 36% (95% CI 29%-45%) and 48% (95% CI 36%-65%), respectively.

In multivariate analysis, HCT in CR3/PD was associated with inferior OS (HR 4.3, p<0.001) and higher NRM (HR 2.3, p=0.04, Table 2), however there was no difference in survival between HCT at CR1 vs. CR2 (p=0.3); >2 lines of therapy prior to HCT was associated with inferior OS (HR 1.8, p=0.004) and higher rate of progression (HR 1.9, p=0.008); HCT-CI>3 was associated with inferior OS (HR 1.6, p=0.01) and higher NRM (2.3, p=0.004); positive MRD status prior to HCT was associated with inferior OS (HR 1.9, p=0.004) and higher rate of progression (HR 3.3, p<0.001); use of bone marrow graft was associated with lower rate of progression (HR 0.6, p=0.02) and use of a matched donor (MSD/MUD) was associated with lower NRM (HR 0.5, p=0.01).

Conclusions: In this analysis of a large dual-center cohort of AYA PhALL patients that received HCT, we found that patients transplanted in CR1 had the most favorable outcomes with 69% 3-year OS. Patients not in CR1/CR2, patients who received HCT after >2 lines of therapy and those with positive MRD pre-HCT had inferior OS on MVA. Although patients who received HCT at CR3/PD had inferior OS, an estimated one-third of patients were still alive at 3 years after HCT.

Disclosures: Short: Novartis: Consultancy; Astellas: Research Funding; Stemline therapeutics: Research Funding; AstraZeneca: Consultancy; Takeda: Consultancy, Research Funding; Amgen: Honoraria; Pfizer: Consultancy. Jabbour: Takeda: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy, Honoraria, Research Funding; Genentech: Consultancy, Honoraria, Research Funding; Astex: Honoraria, Research Funding; Adaptive Biotech: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Research Funding; Hikma Pharmaceuticals: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Research Funding; Ascentage Pharma Group: Consultancy, Honoraria, Research Funding; Bristol-Myers Squibb: Consultancy, Honoraria, Research Funding; Abbvie: Consultancy, Honoraria, Research Funding. Ho: Orca Bio: Consultancy; Alexion: Speakers Bureau; Omeros: Consultancy; Allovir: Consultancy; Alexion: Consultancy; CareDx: Research Funding; Omeros: Research Funding; Jazz: Research Funding. Soiffer: Neovii: Consultancy; Smart Immune: Consultancy; Bluesphere Bio: Consultancy; Jasper: Consultancy; Juno Therapeutics/ BMS/Celgene USA: Other: Data Safety Monitoring Board; NMPD – Be the Match, USA: Membership on an entity's Board of Directors or advisory committees; Vor Bipharma: Consultancy; Astellas: Consultancy. Koreth: Mallinckrodt: Membership on an entity's Board of Directors or advisory committees; Equillium: Consultancy; Gentibio: Consultancy; Cue Biopharma: Consultancy; Biolojic Design: Consultancy; Tr1x: Consultancy; Amgen: Research Funding; Clinigen Labs: Consultancy, Research Funding; BMS: Research Funding; Miltenyi Biotec: Research Funding; Regeneron: Research Funding; Equillium: Research Funding; Cugene: Membership on an entity's Board of Directors or advisory committees. Cutler: Cimeio: Membership on an entity's Board of Directors or advisory committees; Rigel: Consultancy; Oxford Immune Algorithmics: Membership on an entity's Board of Directors or advisory committees; Sanofi: Consultancy; Astellas: Consultancy; InhibRx: Consultancy; Pluristem Therapeutics: Other: DSMB; Allovir: Other: Data Safety Monitoring Board (DSMB). DeAngelo: AbbVie, Glycomimetics, Novartis, Blueprint Pharmaceuticals: Research Funding; Amgen, Autolus Therapeutics, Agios, Blueprint, Forty-Seven, Gilead, Incyte, Jazz, Novartis, Pfizer, Servier, Takeda: Consultancy. Kantarjian: Immunogen (Inst): Honoraria, Research Funding; Daiichih-Sankyo (Inst): Honoraria, Research Funding; AstraZeneca/MedImmune: Honoraria; Astellas Pharma: Honoraria; Ascentage Pharma Group: Honoraria; Amgen: Honoraria; Abbvie: Consultancy, Honoraria; Bristol-Myers Squibb (Inst): Research Funding; Precision Biosciences: Honoraria; Pfizer: Honoraria; Novartis: Honoraria; KAHR Medical: Honoraria; Ipsen: Honoraria; Jazz Pharmaceuticals (Inst): Honoraria, Research Funding; Shenzhen Target Rx: Honoraria; Taiho Pharmaceutical: Honoraria; Abbvie (Inst): Research Funding; Amgen (Inst): Research Funding; Ascentage Pharma (Inst): Research Funding; Novartis (Inst): Research Funding. Champlin: Kadmon: Consultancy; Arog: Consultancy; Orca Bio: Consultancy; Takeda Corporation: Patents & Royalties; Cell Source: Research Funding; Actinium Pharmaceuticals: Consultancy; Omeros: Consultancy; Johnson & Johnson/Janssen: Consultancy. Shpall: Syena: Other: License agreement; Affimed: Other: License agreement; Fibrobiologics: Membership on an entity's Board of Directors or advisory committees; Navan: Membership on an entity's Board of Directors or advisory committees; Adaptimmune: Membership on an entity's Board of Directors or advisory committees; NY Blood Center: Membership on an entity's Board of Directors or advisory committees; Takeda: Other: License agreement; Celaid Therapeutics: Membership on an entity's Board of Directors or advisory committees; Axio: Membership on an entity's Board of Directors or advisory committees. Luskin: Jazz: Honoraria; Pfizer: Honoraria; Novartis: Research Funding; Novartis: Honoraria; AbbVie: Research Funding. Kebriaei: Pfizer: Consultancy, Honoraria; Jazz: Consultancy, Honoraria.

*signifies non-member of ASH