Blinatumomab Therapy Is Associated with Favorable Outcomes after Allogeneic Hematopoietic Cell Transplantation in Pediatric Patients with B Cell Acute Lymphoblastic Leukemia.

Blinatumomab, a bispecific T cell engager that binds CD19 in leukemic cells and CD3 in cytotoxic T cells and leads to leukemic blast lysis, is often used in pediatric patients with relapsed/refractory (R/R) B cell acute lymphoblastic leukemia (B-ALL) prior to allogeneic hematopoietic cell transplantation (allo-HCT). Concerns about the potential risk of blinatumomab-related immune-mediated toxicities after allo-HCT have not been adequately addressed. These include graft-versus-host disease (GVHD), delayed engraftment, and graft failure or rejection. Pediatric-specific data reporting post-HCT outcomes of patients treated with blinatumomab are scarce and limited to small cohorts. We sought to investigate the clinical outcomes of pediatric patients with R/R B-ALL who received blinatumomab therapy pre-HCT, focusing on overall survival (OS), leukemia-free survival (LFS), cumulative incidence of relapse (CIR), and nonrelapse mortality (NRM), as well as the incidence of immune-mediated post-HCT complications including GVHD, delayed neutrophil or platelet engraftment, graft failure, and graft rejection. We also investigated blinatumomab's effects on B cell reconstitution based on achievement of i.v. immunoglobulin (IVIG) independence post-HCT. This single-center, retrospective study included patients with B-ALL receiving blinatumomab therapy before undergoing allo-HCT, with transplantation performed between 2016 and 2021 at our institution. Patients receiving blinatumomab for relapse after allo-HCT were excluded. Patients receiving chemotherapy alone before allo-HCT during the same period composed the control group. Seventy-two patients were included, 31 of whom received blinatumomab before allo-HCT. Survival estimates were obtained using the Kaplan-Meier method, and the log-rank test was used to analyze differences between groups. Categorical variables were compared between groups using the chi-square test or Fisher exact test, and continuous variables were compared using the Wilcoxon rank-sum test. Cumulative incidences were estimated using the competing risks method, and Gray's test was used to analyze differences between groups. A Cox proportional hazards regression model was used for univariate and multivariable analyses for OS. Landmark analysis was performed at the set time points of 30 days and 100 days post-allo-HCT. Most patients in the study cohort had high-risk relapsed B-ALL. Blinatumomab therapy induced minimal residual disease (MRD)-negative remissions in all patients, whereas 5 patients (12.2%) receiving chemotherapy alone had persistent MRD pre-allo-HCT. Time from the start of therapy to the date of allo-HCT was shorter for patients who received blinatumomab compared with those who received chemotherapy (P < .0001). Blinatumomab therapy was associated with greater LFS compared to chemotherapy alone (P = .049), but when limited to 1 year, LFS was not significantly different from control (P = .066). There appeared to be higher OS, lower CIR, and lower NRM in patients receiving blinatumomab compared to the control group; however, the differences were not significant. None of the variables assessed in multivariable analysis was associated with differences in OS. When compared to the controls, blinatumomab therapy did not result in a higher incidence of acute or chronic GVHD, delayed neutrophil or platelet engraftment, or graft failure or rejection. The time to IVIG infusion independence post-allo-HCT was similar in the 2 groups. This study supports the use of blinatumomab salvage therapy for R/R B-ALL before allo-HCT given its efficacy in inducing MRD-negative remissions and optimizing LFS, as well as its lack of association with an increased incidence of post-allo-HCT adverse immune-mediated toxicities. Larger, prospective studies are needed to confirm these findings and to investigate blinatumomab's effects in long-term post-allo-HCT events.

Severe Pediatric COVID-19 Pneumonia Treated With Adjuvant Anakinra.

BACKGROUND AND OBJECTIVES: To compare previous hemophagocytic lymphohistiocytosis criteria with adult coronavirus disease 2019 (COVID-19)-associated hyperinflammatory syndrome (cHIS) criteria for the diagnosis of hyperinflammation in pediatric patients with COVID-19. The secondary objective was to assess treatment response to intravenous (IV) anakinra in these patients. METHODS: This case series included children admitted to the PICU for COVID-19 pneumonia with hyperinflammation and treated with IV anakinra between July 2020 to April 2021. Hyperinflammatory criteria were determined for each patient. Clinical course, chest imaging, and inflammatory marker trends were assessed pre- and post-anakinra treatment. RESULTS: All patients had a cHIS criteria score of ≥5. Two patients met 2004-hemophagocytic lymphohistiocytosis criteria. Only the patient that required extracorporeal membrane oxygenation met the H-Score cut-off value. All but one patient had a decrease in their inflammatory markers and improvement in clinical status with early initiation of adjunctive IV anakinra. CONCLUSIONS: In this case series, adult cHIS criteria were successfully used to identify pediatric COVID-19 patients with hyperinflammation. Ferritin levels decreased after the early initiation of IV anakinra.

Successful Elosulfase Alfa Desensitization Protocol in a Patient With Morquio A Syndrome.

Patients with lysosomal storage diseases may require modifications to standard drug desensitization protocols; personalized medicine as well as development of new treatment options are needed.