Tallman, Martin

Abstract E1910 evaluated the addition of blinatumomab to chemotherapy in adults with B-acute lymphoblastic leukemia (ALL). The addition of blinatumomab in patients (pts) with measurable residual disease (MRD) negative (neg) B-ALL significantly improved both relapse-free and overall survival (NEJM 2024; 391: 320-33)1. Given the increasing use of blinatumomab and the E1910 backbone chemotherapy regimen, we evaluated > Grade 3 toxicities on this trial in further detail. We assessed toxicity among the MRD-neg pts by age, gender, body mass index (BMI), combined cytogenetic-molecular risk, and number of cycles of blinatumomab received. We also evaluated toxicities during induction since this trial used a modified chemotherapy backbone. Methods: The eligibility, combined cytogenetic-molecular risk, and treatment have been previously described.1 All toxicities were > Grade 3 by CTCAE version 4 with at least a possible relationship to treatment. Descriptive statistics were used to summarize the occurrence and rates of toxicities and Fisher's exact test was used to compare differences in proportions between groups. Analysis of induction included all pts who started treatment. Analysis of Step 3 toxicities included MRD-neg pts who started treatment on the blinatumomab (n=111) or chemotherapy only arm (n=112). Results: Pt characteristics: For induction (n=488), median age was 51 years (yrs) (range 30-70); 48.6% female. Combined cytogenetic-molecular risk: favorable (13.5%); intermediate (12.9%); no risk assigned (16.2%); unfavorable (57.4%). For induction, we compared toxicities for E1910 (n=488) to pts treated on a prior young adult study (n=289) (C10403) (Blood Adv 2021; 5(2): 504-12). The incidence of hyperglycemia (8% vs. 31.1%, p< 0.001), aspartate aminotransferase (AST) increase (6.1% vs. 12.8%, p=0.002), alanine aminotransferase increase (ALT) (11.7% vs. 28.7%, p< 0.001), and hyperbilirubinemia (11% vs. 19%, p=0.002) were significantly lower in E1910 pts. The incidence of pancreatitis (1.8%), thromboembolic events (4.5%), and febrile neutropenia (25.4%) in E1910 was similar to C10403. Toxicities in the MRD-neg pts in the blinatumomab arm (n=111): Despite a high incidence of neutropenia (74.8%) and thrombocytopenia (55.9%) in Step 3, there was a relatively low incidence of sepsis (7.2%), bacteremia (1.8%), cytokine release syndrome (CRS) (3.6%) and neurologic adverse events (0-6.3%). There was a higher incidence of neurological or psychiatric events in the blinatumomab arm (23%) versus chemotherapy arm (5%) (p < 0.001) when all events were combined. There was a numerically higher incidence of ataxia (4.4% vs. %, p=0.16) and dysphasia (11.1% vs. 3%, p=0.12) in pts > 55 yrs and a higher incidence of neutropenia (80.3% vs. 66.7%, p=0.12) and thrombocytopenia (62.1% vs. 46.7%, p=0.12) in the younger pts (age < 55 yrs). In pts with a BMI < 30 kg/m2 (vs. > 30 kg/m2), there was a significantly higher incidence of leukopenia (51.7% vs. 26.4%, p=0.007) and thrombocytopenia (65.5% vs. 45.3%, p=0.037). However, this did not translate into an increased incidence of bleeding or infectious complications. By gender, females had a higher numerical incidence of AST increase (8.8% vs. 0%, p=0.057) and CRS (7% vs. 0% p=0.12); whereas males had a higher incidence of catheter- related infections (7.4% vs. 0%, p=0.05) and hyperglycemia (11.1% vs. 3.5%, p=0.16). A little more than half (56.8%) of pts received 4 cycles of blinatumomab with the remainder of pts receiving 1 (10.8%), 2 (28.8%), or 3 cycles (3.6%). Pts receiving 3-4 cycles of blinatumomab vs. 1-2 cycles of blinatumomab had a statistically higher incidence of anemia (38.8% vs. 6.8%, p< 0.001), neutropenia (98.5% vs. 38.6%, p< 0.001), and thrombocytopenia (83.6% vs. 13.6%, p< 0.001), likely related to being on treatment for a longer period of time. Conclusions: Blinatumomab was well tolerated with no significant toxicity differences noted by age, gender, or number of cycles of blinatumomab received. Pts with a lower BMI did have an increased incidence of leukopenia and thrombocytopenia, possibly related to flat dosing of the drug. However, this did not translate into increased complications. Toxicites during induction were notably few, which suggests that this backbone with age adjustments may serve as a good backbone for future trials. Blinatumomab is being evaluated with low dose chemotherapy and other targeted agents in ongoing trials.

Purpose To develop a system prognostic of outcome in those undergoing allogeneic hematopoietic cell transplantation (allo HCT) for myelodysplastic syndrome (MDS). Patients and Methods We examined 2,133 patients with MDS undergoing HLA-matched (n = 1,728) or -mismatched (n = 405) allo HCT from 2000 to 2012. We used a Cox multivariable model to identify factors prognostic of mortality in a training subset (n = 1,151) of the HLA-matched cohort. A weighted score using these factors was assigned to the remaining patients undergoing HLA-matched allo HCT (validation cohort; n = 577) as well as to patients undergoing HLA-mismatched allo HCT. Results Blood blasts greater than 3% (hazard ratio [HR], 1.41; 95% CI, 1.08 to 1.85), platelets 50 × 109/L or less at transplantation (HR, 1.37; 95% CI, 1.18 to 1.61), Karnofsky performance status less than 90% (HR, 1.25; 95% CI, 1.06 to 1.28), comprehensive cytogenetic risk score of poor or very poor (HR, 1.43; 95% CI, 1.14 to 1.80), and age 30 to 49 years (HR, 1.60; 95% CI, 1.09 to 2.35) were associated with increased hazard of death and assigned 1 point in the scoring system. Monosomal karyotype (HR, 2.01; 95% CI, 1.65 to 2.45) and age 50 years or older (HR, 1.93; 95% CI, 1.36 to 2.83) were assigned 2 points. The 3-year overall survival after transplantation in patients with low (0 to 1 points), intermediate (2 to 3), high (4 to 5) and very high (≥ 6) scores was 71% (95% CI, 58% to 85%), 49% (95% CI, 42% to 56%), 41% (95% CI, 31% to 51%), and 25% (95% CI, 4% to 46%), respectively (P < .001). Increasing score was predictive of increased relapse (P < .001) and treatment-related mortality (P < .001) in the HLA-matched set and relapse (P < .001) in the HLA-mismatched cohort. Conclusion The proposed system is prognostic of outcome in patients undergoing HLA-matched and -mismatched allo HCT for MDS.