Comparing 2-day vs 3-day flu-CY lymphodepleting regimens for CD19 CAR T-cell therapy in patients with non-hodgkin's lymphoma.

Introduction: Lymphodepleting chemotherapy (LDC) is critical to CAR T-cell expansion and efficacy. Despite this, there is not a consensus in the literature regarding the optimal LDC regimen, including dose and frequency. Methods: We retrospectively reviewed consecutive patients at a single institution that received LDC prior to treatment with the CD19 directed CAR T-cell products axicabtagene ciloleucel and tisagenlecleucel. Patients treated at our center received fludarabine 30 mg/m2 and cyclophosphamide 500 mg/m2 for 3 consecutive days prior to May 2019. After this timepoint patients routinely received fludarabine 40 mg/m2 and cyclophosphamide 500 mg/m2 for 2 consecutive days. Clinical data from each cohort were obtained from the electronic medical record and compared for differences in CAR T-cell efficacy and toxicity. Results: From June 2018 to August 2023, LDC was given to 92 patients prior to CD19 directed CAR T-cell therapy for relapsed non-Hodgkin's lymphoma. Twenty-eight patients received a 3-day regimen, and 64 patients received a 2-day regimen. In the total cohort, 75% of patients received axicabtagene ciloleucel and 25% received tisagenlecleucel. The overall response rates in both the 2-day regimen group and the 3-day regimen group were similar (69% vs 75%, p= 0.21) as were the complete response rates (50% vs 54%, p=0.82). There were no significant differences between the 2-day and 3-day regimens for grade 2-4 cytokine release syndrome (55% vs 50%, p=0.82), grade 2-4 immune effector cell associated-neurotoxicity syndrome (42% vs 29%, p=0.25), or time to resolution of neutropenia or thrombocytopenia. The rate of prolonged platelet recovery lasting greater than 60 days was higher with the 3-day regimen (9% vs 27%, p=0.026). Discussion: As the number of patients eligible for CAR T-cell therapy continues to increase, optimizing each component of therapy is necessary. We show that a 2-day regimen of LDC with fludarabine and cyclophosphamide is feasible without significant impact on CAR T-cell efficacy or toxicity. Prospective studies are necessary to further determine the most effective LDC regimen.

Donor types and outcomes of transplantation in myelofibrosis: a CIBMTR study.

ABSTRACT: We evaluate the impact of donor types on outcomes of hematopoietic cell transplantation (HCT) in myelofibrosis, using the Center for International Blood and Marrow Transplant Research registry data for HCTs done between 2013 and 2019. In all 1597 patients, the use of haploidentical donors increased from 3% in 2013 to 19% in 2019. In study-eligible 1032 patients who received peripheral blood grafts for chronic-phase myelofibrosis, 38% of recipients of haploidentical HCT were non-White/Caucasian. Matched sibling donor (MSD)-HCTs were associated with superior overall survival (OS) in the first 3 months (haploidentical hazard ratio [HR], 5.80 [95% confidence interval (CI), 2.52-13.35]; matched unrelated (MUD) HR, 4.50 [95% CI, 2.24-9.03]; mismatched unrelated HR, 5.13 [95% CI, 1.44-18.31]; P < .001). This difference in OS aligns with lower graft failure with MSD (haploidentical HR, 6.11 [95% CI, 2.98-12.54]; matched unrelated HR, 2.33 [95% CI, 1.20-4.51]; mismatched unrelated HR, 1.82 [95% CI, 0.58-5.72]). There was no significant difference in OS among haploidentical, MUD, and mismatched unrelated donor HCTs in the first 3 months. Donor type was not associated with differences in OS beyond 3 months after HCT, relapse, disease-free survival, or OS among patients who underwent HCT within 24 months of diagnosis. Patients who experienced graft failure had more advanced disease and commonly used nonmyeloablative conditioning. Although MSD-HCTs were superior, there is no significant difference in HCT outcomes from haploidentical and MUDs. These results establish haploidentical HCT with posttransplantation cyclophosphamide as a viable option in myelofibrosis, especially for ethnic minorities underrepresented in the donor registries.

Amphiregulin, ST2, and REG3α biomarker risk algorithms as predictors of nonrelapse mortality in patients with acute GVHD.

ABSTRACT: Graft-versus-host disease (GVHD) is a major cause of nonrelapse mortality (NRM) after allogeneic hematopoietic cell transplantation. Algorithms containing either the gastrointestinal (GI) GVHD biomarker amphiregulin (AREG) or a combination of 2 GI GVHD biomarkers (suppressor of tumorigenicity-2 [ST2] + regenerating family member 3 alpha [REG3α]) when measured at GVHD diagnosis are validated predictors of NRM risk but have never been assessed in the same patients using identical statistical methods. We measured the serum concentrations of ST2, REG3α, and AREG by enzyme-linked immunosorbent assay at the time of GVHD diagnosis in 715 patients divided by the date of transplantation into training (2004-2015) and validation (2015-2017) cohorts. The training cohort (n = 341) was used to develop algorithms for predicting the probability of 12-month NRM that contained all possible combinations of 1 to 3 biomarkers and a threshold corresponding to the concordance probability was used to stratify patients for the risk of NRM. Algorithms were compared with each other based on several metrics, including the area under the receiver operating characteristics curve, proportion of patients correctly classified, sensitivity, and specificity using only the validation cohort (n = 374). All algorithms were strong discriminators of 12-month NRM, whether or not patients were systemically treated (n = 321). An algorithm containing only ST2 + REG3α had the highest area under the receiver operating characteristics curve (0.757), correctly classified the most patients (75%), and more accurately risk-stratified those who developed Minnesota standard-risk GVHD and for patients who received posttransplant cyclophosphamide-based prophylaxis. An algorithm containing only AREG more accurately risk-stratified patients with Minnesota high-risk GVHD. Combining ST2, REG3α, and AREG into a single algorithm did not improve performance.

Cardiovascular Risk Stratification of Patients Undergoing Hematopoietic Stem Cell Transplantation: The CARE-BMT Risk Score.

BACKGROUND: Evidence guiding the pre-hematopoietic stem cell transplantation (HSCT) cardiovascular evaluation is limited. We sought to derive and validate a pre-HSCT score for the cardiovascular risk stratification of HSCT candidates. METHODS AND RESULTS: We leveraged the CARE-BMT (Cardiovascular Registry in Bone Marrow Transplantation) study, a contemporary multicenter observational study of adult patients who underwent autologous or allogeneic HSCT between 2008 and 2019 (N=2435; mean age at transplant of 55 years; 4.9% Black). We identified the subset of variables most predictive of post-HSCT cardiovascular events, defined as a composite of cardiovascular death, myocardial infarction, heart failure, stroke, atrial fibrillation or flutter, and sustained ventricular tachycardia. We then developed a point-based risk score using the hazard ratios obtained from Cox proportional hazards modeling. The score was externally validated in a separate cohort of 919 HSCT recipients (mean age at transplant 54 years; 20.4% Black). The risk score included age, transplant type, race, coronary artery disease, heart failure, peripheral artery disease, creatinine, triglycerides, and prior anthracycline dose. Risk scores were grouped as low-, intermediate-, and high-risk, with the 5-year cumulative incidence of cardiovascular events being 4.0%, 10.3%, and 22.4%, respectively. The area under the receiver operating curves for predicting cardiovascular events at 100 days, 5 and 10 years post-HSCT were 0.65 (95% CI, 0.59-0.70), 0.73 (95% CI, 0.69-0.76), and 0.76 (95% CI, 0.69-0.81), respectively. The model performed equally well in autologous and allogeneic recipients, as well as in the validation cohort. CONCLUSIONS: The CARE-BMT risk score is easy to calculate and could help guide referrals of high-risk HSCT recipients to cardiovascular specialists before transplant and guide long-term monitoring.

Cardiovascular Events After Hematopoietic Stem Cell Transplant: Incidence and Risk Factors.

Background: Hematopoietic stem cell transplantation (HSCT) is associated with various cardiovascular (CV) complications. Objectives: We sought to characterize the incidence and risk factors for short-term and long-term CV events in a contemporary cohort of adult HSCT recipients. Methods: We conducted a multicenter observational study of adult patients who underwent autologous or allogeneic HSCT between 2008 and 2019. Data on demographics, clinical characteristics, conditioning regimen, and CV outcomes were collected through chart review. CV outcomes were a composite of CV death, myocardial infarction, heart failure, atrial fibrillation/flutter, stroke, and sustained ventricular tachycardia and were classified as short-term (≤100 days post-HSCT) or long-term (>100 days post-HSCT). Results: In 3,354 patients (mean age 55 years; 40.9% female; 30.1% Black) followed for a median time of 2.3 years (Q1-Q3: 1.0-5.4 years), the 100-day and 5-year cumulative incidences of CV events were 4.1% and 13.9%, respectively. Atrial fibrillation/flutter was the most common short- and long-term CV event, with a 100-day incidence of 2.6% and a 5-year incidence of 6.8% followed by heart failure (1.1% at 100 days and 5.4% at 5 years). Allogeneic recipients had a higher incidence of long-term CV events compared to autologous recipients (5-year incidence 16.4% vs 12.1%; P = 0.002). Baseline CV comorbidities were associated with a higher risk of long-term CV events. Conclusions: The incidence of short-term CV events in HSCT recipients is relatively low. Long-term events were more common among allogeneic recipients and those with pre-existing CV comorbidities.