(012) Assess the Safety and Efficacy of Blinatumomab and Inotuzumab with Chemotherapy in Relapsed and Refractory Ph-negative B-cell Acute Lymphoblastic Leukemia at an Academic Medical Center

Poster Abstract:

Background: B-cell acute lymphoblastic leukemia (ALL) has an initial good response to treatment however duration of remission is short and about 50% of patients relapse. Relapsed and refractory (r/r) B-cell ALL has a poor prognosis, therefore, induction of remission with sufficient duration of time to receive a hematopoietic cell transplantation (HCT) is crucial to improve survival outcomes. Guidelines recommend Blinatumomab or Inotuzumab in patients with r/r disease. Studies also demonstrated that the use of these novel agents with systemic chemotherapy was associated with higher survival rates when compared to chemotherapy alone. At Harris Health System, providers are using chemotherapy with blinatumomab and/or inotuzumab in the r/r setting, however safety and efficacy are yet to be evaluated.

Objective(s): This study aims to assess the safety and efficacy of using blinatumomab and/or inotuzumab with chemotherapy in patients with r/r Philadelphia negative (Ph-) B-cell ALL.

Method(s): This is a single-center, multi-site, retrospective review evaluating the safety and efficacy of blinatumomab and/or inotuzumab with chemotherapy in patients with r/r Ph- B-cell ALL. Adult patients 18 or older with a diagnosis of r/r Ph- B-cell ALL who received blinatumomab and/or inotuzumab between December 31, 2014, and December 31, 2023, will be included. Patients with additional active malignancies and T-cell ALL will be excluded from the study. Baseline demographics, laboratory criteria, cytogenetics/pathology information, treatment duration and dosing, toxicities, transplant status, relapse of disease, or death information will be reviewed. The primary endpoints are adverse drug events (ADEs), time to complete remission, and negative minimal residual disease (MRD). Secondary endpoints include relapse-free survival (RFS) and rate of subsequent allogeneic stem cell transplantation (ASCT). Continuous and numerical data will be analyzed using the student t-test or Mann-Whitney test based on the distribution of the data. Categorical and discrete data will be compared using the Fisher’s exact or Chi-square test. Descriptive statistics will be utilized where appropriate. A Kaplan-Meier analysis will be used to assess relapse-free survival. A 2-sided p-value < 0.05 will be considered statistically significant.

Result(s): Results pending.

Conclusion(s): Results pending.

References (must also be included in final poster): 1. Jabbour E, Ravandi F, Kebriaei P, et al. Salvage Chemoimmunotherapy With Inotuzumab Ozogamicin Combined With Mini-Hyper-CVD for Patients With Relapsed or Refractory Philadelphia Chromosome-Negative Acute Lymphoblastic Leukemia: A Phase 2 Clinical Trial. JAMA Oncol. 2018;4(2):230-234.

2. Jabbour E, Sasaki K, Short NJ, et al. Long-term follow-up of salvage therapy using a combination of inotuzumab ozogamicin and mini-hyper-CVD with or without blinatumomab in relapsed/refractory Philadelphia chromosome-negative acute lymphoblastic leukemia. Cancer. 2021;127(12):2025-2038.

3. Kantarjian H, Stein A, Gökbuget N, et al. Blinatumomab versus Chemotherapy for Advanced Acute Lymphoblastic Leukemia. N Engl J Med. 2017;376(9):836-847.

4. Kantarjian HM, DeAngelo DJ, Stelljes M, et al. Inotuzumab ozogamicin versus standard of care in relapsed or refractory acute lymphoblastic leukemia: Final report and long-term survival follow-up from the randomized, phase 3 INO-VATE study. Cancer. 2019;125(14):2474-2487.

5. Kantarjian HM, DeAngelo DJ, Stelljes M, et al. Inotuzumab Ozogamicin versus Standard Therapy for Acute Lymphoblastic Leukemia. N Engl J Med. 2016;375(8):740-753.

6. National Comprehensive Cancer Network® (NCCN®). Acute Lymphoblastic Leukemia (Version 2.2023) https://www.nccn.org/professionals/physician_gls/pdf/all.pdf. Accessed August 12, 2023.

7. Topp MS, Stein AS, Gökbuget N, et al. Blinatumomab as first salvage versus second or later salvage in adults with relapsed/refractory B-cell precursor acute lymphoblastic leukemia: Results of a pooled analysis. Cancer Med. 2021;10(8):2601-2610.