Frangoul, Haydar

Abstract Introduction Elevated levels of fetal hemoglobin (HbF) ameliorate sickle cell disease (SCD) manifestations. BEAM-101 is an investigational cell therapy comprising ex vivo base-edited autologous CD34+ hematopoietic stem and progenitor cells (HSPCs) that directly target the HBG1/2 promoters to disrupt BCL11A binding, switching production from sickle (HbS) to majority anti-sickling HbF. We present ongoing data from the BEACON study (NCT05456880), a Phase 1/2, single-arm, open-label study evaluating a single dose of BEAM-101 in individuals with SCD and severe vaso-occlusive crises (sVOCs). Methods Eligible patients were aged 12–35 years with SCD and ≥4 sVOCs in the 2-year period prior to informed consent. After mobilization with weight-based or tiered fixed-dose plerixafor, autologous CD34+ HSPCs were collected by leukapheresis and genetically modified with an adenine base editor. Following conditioning with pharmacokinetically adjusted myeloablative busulfan (target cumulative AUC 80 hr*mg/L), patients received a single dose of BEAM-101 (≥3.0×106 viable CD34+ cells/kg). Patients were then monitored for neutrophil and platelet engraftment, adverse events (AEs), total Hb, Hb fractions, % F-cells, hemolysis markers, sVOCs, and additional protocol endpoints for up to 24 months. Results As of June 16, 2025, enrollment has been completed and 46 patients have initiated mobilization. Of the 26 patients who have received BEAM-101, mean duration of follow-up was 6.2 (range 1.0–18.7) months. Baseline demographics were: age 18–34 years, 24 βS/βS genotype, 21 self-reported Black/African American, and 11 female. One patient, who successfully engrafted and obtained stable HbF levels >60%, withdrew consent 5 months post-infusion. For the 26 treated patients, the median number of stem cell collection cycles was 1 (range 1–4); 18 (69.2%) required a single cycle, 4 required 2 cycles, and 4 required >2 cycles. Target cell dose was achieved with a median of 3 (1–12) collection days. Patients received a mean BEAM-101 dose of 8.4 (range 3.2–23.4) ×106 viable CD34+ cells/kg. By the data cut, patients achieved neutrophil (n=26) and platelet (n=24) engraftment at a median of 18 (12–30) days and 19 (11–50) days, respectively, with a median duration of 7 (4–17) days of neutropenia. Of the 24 evaluable patients, 9 (37.5%) achieved platelet engraftment without requiring platelet transfusion through the transplant process. No patients had ≥Grade 3 AEs or serious AEs related to BEAM-101. One patient died due to respiratory failure, assessed as likely related to busulfan conditioning, 4 months post-infusion as previously reported. Mean total Hb increased to 12.1 (range 9.0–14.7) g/dL by Month (M) 1 (n=24), 15.6 (11.9–18.6) g/dL by M6 (n=11), and was sustained through follow-up. Four patients had total Hb levels above the normal range beyond M6 without any associated clinical manifestations or need for therapeutic intervention. Erythropoietin levels trended towards normal in all patients, including those with elevated total Hb. Mean endogenous HbF (HbF/[HbF+HbS]) was >60% and HbS was <40% by M1, which was sustained through last follow-up. At M6, mean % F-cells were 99.2% (97.0–99.9; n=10) and mean HbF/F-cell was 20.8 (18.0–23.9; n=9) pg, exceeding the protective threshold of 10 pg against sickling. Peripheral blood editing was at a mean of 68.5% by M3 (n=16), 69.6% by M6 (n=10), and 72.8% by M12 (n=5). Hemolysis markers and sickling parameters normalized or improved for all patients. No patients experienced any investigator-reported sVOCs post-engraftment. Conclusions The BEAM-101 treatment process is characterized by a low number of mobilization and collection cycles and high editing efficiency, resulting in rapid neutrophil and platelet engraftment and robust pancellular HbF expression, with durability observed up to 18 months. Additionally, there is a corresponding reduction in HbS levels to <40%, and improvements or resolution of hemolysis parameters and anemia, along with resolution of investigator-reported sVOCs post-engraftment. The safety profile of the BEAM-101 treatment regimen is consistent with busulfan conditioning, autologous HSCT, and underlying SCD. These results demonstrate the potential for base editing of the HBG1/2 promoters as a safe and effective therapeutic modality for the treatment of SCD that also has the potential to minimize hospitalization and treatment process burden for patients, families, and sites.

ABSTRACTBackgroundIn this study, we compared outcomes of intensified myeloablative conditioning regimens using large registry data from Japan (Japanese Society for Transplantation and Cellular Therapy) and the United States (Center for International Blood and Marrow Transplant Research).MethodsAdult patients who underwent their first myeloablative allogeneic hematopoietic stem cell transplantation (HSCT) for acute leukemia in remission between 2010 and 2018 using conditioning regimens of cyclophosphamide plus total‐body irradiation (CY/TBI), CY/TBI+cytarabine (AraC), or CY/TBI+etoposide (VP16) were included.ResultsThe acute myeloid leukemia (AML) cohort (N = 480, 38.8%) indicated that overall survival (OS) was poorer in CY/TBI+AraC (hazard ratio [HR] 1.46, p < 0.001) and CY/TBI+VP16 (HR 1.39, p = 0.059) compared to CY/TBI. Relapse was not suppressed, while treatment‐related mortality (TRM) was significantly higher (HR 1.78 and 1.74, p < 0.001 and 0.018, respectively). In the acute lymphoblastic leukemia (ALL) cohort (N = 3901, 61.2%), OS was comparable among these regimens. With intensified regimens, relapse was significantly suppressed in CY/TBI+VP16 (HR 0.74, p = 0.005), while TRM was higher (HR 1.21, p = 0.077). No interactions were observed regarding the country.ConclusionIn AML adding AraC and VP16 to CY/TBI had an adverse effect on OS. Conversely, in ALL, adding VP16 or AraC to CY/TBI did not affect survival, but the addition of VP16 reduced the risk of relapse.Clinical Trial RegistrationThe authors have confirmed clinical trial registration is not needed for this submission.

Fetal hemoglobin (HbF) is anti-sickling and elevated HbF ameliorates sickle cell disease (SCD) manifestations. BEAM-101 is an investigational cell therapy comprised of autologous CD34+ hematopoietic stem and progenitor cells (HSPCs) that are base edited ex vivo to introduce naturally occurring A-to-G substitutions into the promoters of the HBG1/2 genes that encode γ-globin to disrupt BCL11A transcriptional repressor binding sites, leading to increased HbF production. We previously demonstrated in pre-clinical studies that base editing potently induced HbF (&gt;60%) and proportionately reduced sickle hemoglobin (HbS) (&lt;40%) without relying on double-stranded DNA breaks. We present initial data from BEACON (NCT05456880), a Phase 1/2, single-arm, open-label study evaluating the safety and efficacy of a single dose of BEAM-101 in patients with SCD with severe vaso-occlusive crises (VOCs). Patients 18-35 years diagnosed with SCD and ≥4 severe VOCs in the 2-year period prior to screening per trial criteria were eligible. After plerixafor mobilization, autologous CD34+ HSPCs were collected by leukapheresis/isolation and genetically modified with an adenine base editor. After myeloablative conditioning with pharmacokinetically adjusted busulfan, patients received a single infusion of BEAM-101 (≥3.0 × 106 viable CD34+ cells/kg) and are monitored for neutrophil and platelet engraftment, adverse events (AEs), total hemoglobin (Hb), Hb fractions, % F-cells, hemolysis markers, peripheral blood editing, and VOCs for 24 months. As of July 2, 2024, &gt;20 patients are enrolled and BEAM-101 has been manufactured for 8 patients, of whom 6 patients have been dosed. One patient not included in this analysis discontinued during the mobilization/collection period prior to BEAM-101 treatment for non-medical reasons. Baseline demographics were as follows: 5/6 patients βS/βS, 1/6 patients βS/β0, all self-reported Black/African American, 50% female, aged 19-27 years. Of the 6 patients, half (n=3) required only a single mobilization cycle and the other half required 2. Patients received a mean BEAM-101 dose of 11.9 × 106 (5.2-23.4) viable CD34+ cells/kg. Excepting safety data that include all patients dosed (n=6), the following data are from patients dosed with ≥1 month of follow up (n=4; 6, 5, 2, and 1 month[s] post-treatment, each). All 4 patients with ≥1 month of follow up achieved neutrophil and platelet engraftment at a median of 17 (15-19) and 20 (11-34) days, respectively. One patient died due to respiratory failure, likely related to busulfan conditioning, 4 months after infusion. In all patients dosed (n=6), there have been no ≥Grade 3 AEs or serious AEs related to BEAM-101. Using the central laboratory data, patients' total Hb increased from baseline (mean 9.3 [7.9-10.9] g/dL) to 17.9, 18.2, 11.0, and 11.8 g/dL at last time point (LTP) available for P1, P2, P3, and P4, respectively. No signs/symptoms or interventions were undertaken for high total Hb. All patients achieved &gt;60% HbF of non-transfused Hb (total Hb − HbA) at Month (M) 1 and sustained this elevation to the LTP available. By M1, HbS% in non-transfused blood dropped to ≤36% in all 4 patients and was sustained through LTP. In total blood, % F-cells were 99.6% in P1 at M6, 94.4% in P2 at M4, 52.0% in P3 at M2, and 13.3% in P4 at M1 with all patients having &gt;19 pg HbF/F-cell at LTP available. Peripheral blood editing in nucleated cells, measured in P1 (at M6) and P2 (at M3), was 69.9% and 76.1%, respectively. Markers of hemolysis (lactate dehydrogenase, indirect bilirubin, haptoglobin, and reticulocyte counts) have normalized or improved for all patients. No VOCs have been reported by investigators following BEAM-101 treatment. These initial data show a safety profile for BEAM-101 consistent with busulfan conditioning and autologous HSCT. Treatment with BEAM-101 resulted in rapid engraftment, improvement in hemolysis markers, and marked improvement of anemia in all 4 dosed patients. We observed rapid and robust HbF induction consistent with pre-clinical data by M1 (&gt;60%) and corresponding HbS reduction (≤36%) in non-transfused blood in all post-treatment assessments. No VOCs were reported by investigators post-treatment. These initial data support base editing of the HBG1/2 promoters as an effective therapeutic modality for the treatment of SCD and will continue to be investigated in the ongoing BEACON study. Updated data to be presented.

Abstract Social determinants of health, including poverty, contribute significantly to health outcomes in the United States; however, their impact on pediatric hematopoietic cell transplantation (HCT) outcomes is poorly understood. We aimed to identify the association between neighborhood poverty and HCT outcomes for pediatric allogeneic HCT recipients in the Center for International Blood and Marrow Transplant Research database. We assembled 2 pediatric cohorts undergoing first allogeneic HCT from 2006 to 2015 at age ≤18 years, including 2053 children with malignant disease and 1696 children with nonmalignant disease. Neighborhood poverty exposure was defined a priori per the US Census definition as living in a high-poverty ZIP code (≥20% of persons below 100% federal poverty level) and used as the primary predictor in all analyses. Our primary outcome was overall survival (OS), defined as the time from HCT until death resulting from any cause. Secondary outcomes included relapse and transplantation-related mortality (TRM) in malignant disease, acute and chronic graft-versus-host disease, and infection in the first 100 days post-HCT. Among children undergoing transplantation for nonmalignant disease, neighborhood poverty was not associated with any HCT outcome. Among children undergoing transplantation for malignant disease, neighborhood poverty conferred an increased risk of TRM but was not associated with inferior OS or any other transplantation outcome. Among children with malignant disease, a key secondary finding was that children with Medicaid insurance experienced inferior OS and increased TRM compared with those with private insurance. These data suggest opportunities for future investigation of the effects of household-level poverty exposure on HCT outcomes in pediatric malignant disease to inform care delivery interventions.

Abstract INTRODUCTION: Obesity is increasingly common in the US and is frequently associated with co-morbid medical conditions that may increase the risk of HCT, often the optimal treatment for AML. HCT risk and outcomes for AML on the basis of body mass index (BMI) have not been well-characterized. Using data from the Center for International Blood and Marrow Transplant Research (CIBMTR), we have previously shown no significant difference in outcomes for autologous HCT for lymphoma among normal weight, overweight, and obese patients (pts) but worse outcomes for underweight pts (Navarro et al, BBMT 2006, 12(5): 541–51). Here, we compare outcomes by weight groups for AML patients who underwent autologous, related, or unrelated HCT. METHODS: Our final population included patients age ≥ 18 who underwent myeloablative unpurged autologous or allogeneic HCT for AML in 1st or 2nd complete remission, primary induction failure, or 1st relapse reported to the CIBMTR from 1995 to 2004. Cord blood HCTs were excluded. Four weight groups were defined based on BMI (BMI=weight (kg)/ height (m2)): underweight &lt;18; normal=18–25; overweight &gt;25–30; and obese &gt;30. Treatment-related mortality (TRM), relapse, leukemia-free survival (LFS), and overall survival (OS) were compared using multivariable proportional hazards regression analysis accounting for patient, disease and HCT-related variables. RESULTS: We included 373 autologous, 2041 related, and 1801 unrelated transplant recipients. Patient-, disease-, and transplant characteristics were well-matched across weight groups and transplant types. Multivariable analysis examining risks (95% confidence intervals) relative to the normal weight group are: HCT Type Normal Underweight Overweight Obese -- =not done due to insufficient number of pts; NS=not significant; treatment failure = death or recurrence of disease. Autologous n=164 n=5 n=112 n=81 Death -- NS NS Treatment failure -- NS NS Relapse -- NS NS TRM -- NS NS Related Allogeneic n=1161 n=31 n=543 n=268 Death 1.86 (1.24–2.78) NS 1.23 (1.04–1.47) Treatment failure 2.08 (1.37–3.15) NS 1.19 (1.00–1.42) Relapse 2.02 (1.18–3.47) NS NS TRM 2.22 (1.17–4.22) NS 1.32 (1.02–1.70) Unrelated Allogeneic n=846 n=31 n=523 n=368 Death NS NS NS Treatment failure NS NS NS Relapse NS 0.82 (0.68–0.99) 0.76 (0.60–0.96) TRM NS NS NS CONCLUSIONS: There were no significant differences in risk of TRM, LFS, relapse or OS for normal weight, overweight or obese patient groups who received autologous HCT. Obese recipients of related HCT for AML had increased risk of death, treatment failure, and TRM, though the magnitude was small, an effect was not seen in the unrelated HCT group. Underweight patients who received a related, but not unrelated HCT, fared substantially worse than normal weight patients for all outcomes. It may be that the higher risk of the unrelated HCT procedure masks important but less obvious risks associated with being underweight whereas in the related donor HCT setting, such risks become manifest. Small numbers of patients limit the ability to better characterize this finding in underweight patients. Disproportionately, fewer transplants have been reported in underweight patients which suggest they experience disease and patient-related factors that preclude transplantation. No differences were observed for incidence of acute or chronic GVHD for any weight group. Overweight and obesity should not be a barrier to HCT; however, caution should be exercised in selecting underweight patients for HCT.

Abstract Higher bone marrow cell dose has been associated with improved survival after allogeneic BMT. Although PBSC provides higher cell dose, it also provides a higher number of T cells which increases the risk of GVHD and may negatively impact the outcome in pediatric patients. A prospective multi-center trial was conducted to evaluate the safety and feasibility of G-CSF primed bone marrow in children receiving HLA-identical sibling bone marrow transplantation (BMT). Thirty eight children at 9 different centers, 17 female and 21 male with a median age of 9.8 years (range 0.8–17) were enrolled between May 2003 and May 2005. Fifteen patients had high risk diseases (ALL ≥CR2=4, AML≥ CR2/refractory=5, Advanced MDS=3, JMML=1, NHL=2) and 23 had standard risk disease (SAA=6, Red Cell Aplasia=1, Sickle cell disease=1, CML-CP=2, AML CR1=9, ALL CR1=2, MDS-RA=2). Five patients had undergone a prior allogeneic transplant. All patients received myeloablative preparative regimens (Cy/TBI±VP-16=12, BU/Cy±other=20 and Cy/ATG=6) and 32 (84%) received CSP/FK506 with MTX as GVHD prophylaxis. Donors were HLA identical siblings except for one who was syngeneic. Donors with median age of 9.2 y (range 1.1–22) received 5 mcg/kg/day of GCSF SQ for 5 consecutive days. Bone marrow was collected on the fifth day with a median volume of 14.5 cc/kg (range 5.2–25). No donor experienced any complications related to G-CSF administration or harvest, up to the time of last follow-up at one month after the harvest. The absolute CD34 cell count at the day of the harvest was measured in 28 patients and it was significantly higher in bone marrow compared to peripheral blood, median of 50/μl (8–247) vs 513/μl (116–156) respectively (p <0.0001). Median nucleated and CD 34 cells infused was 8.4x108/kg (range 2.4–60.9) and 8.7x106/kg (range 2–27.6) respectively. No G-CSF was administered post transplant. All patients had neutrophil engraftment at a median of 19 days (13–28), and all but one patient with early post-transplant relapse had platelet engraftment at a median of 20 days (9–44). Thirteen patients (35%) developed grade 2 GVHD and 4 of 34 evaluable patients (12%) developed chronic GVHD (3 limited and 1 extensive). There was no transplant related mortality. Among 30 patients with malignant disorders 9 (30%) relapsed (6 with high risk and 3 with standard risk disease). The EFS and OS of patients with standard disease at 1 year is 84% (95% CI 68–100%) and 95% (95% CI 87–100) respectively. With a median follow up of 1 year the estimated EFS and OS of all patients at one year is 76% (CI 62–93) and 92% (95% CI 83–100) respectively. We conclude that G-CSF primed bone marrow from pediatric donors is safe and can result in high NC and CD34 cell dose that facilitate engraftment after myeloablative BMT without a discernable increase in the risk of GVHD. A prospective randomized trial comparing G-CSF primed bone marrow to unstimulated marrow is planned.

ABSTRACT Voriconazole pharmacokinetics are not well characterized in children despite prior studies. To assess the appropriate pediatric dosing, a study was conducted in 40 immunocompromised children aged 2 to <12 years to evaluate the pharmacokinetics and safety of voriconazole following intravenous (IV)-to-oral (PO) switch regimens based on a previous population pharmacokinetic modeling: 7 mg/kg IV every 12 h (q12h) and 200 mg PO q12h. Area under the curve over the 12-h dosing interval (AUC 0–12 ) was calculated using the noncompartmental method and compared to that for adults receiving approved dosing regimens (6→4 mg/kg IV q12h, 200 mg PO q12h). On average, the AUC 0–12 in children receiving 7 mg/kg IV q12h on day 1 and at IV steady state were 7.85 and 21.4 μg·h/ml, respectively, and approximately 44% and 40% lower, respectively, than those for adults at 6→4 mg/kg IV q12h. Large intersubject variability was observed. At steady state during oral treatment (200 mg q12h), children had higher average exposure than adults, with much larger intersubject variability. The exposure achieved with oral dosing in children tended to decrease as weight and age increased. The most common treatment-related adverse events were transient elevated liver function tests. No clear threshold of voriconazole exposure was identified that would predict the occurrence of treatment-related hepatic events. Overall, voriconazole IV doses higher than 7 mg/kg are needed in children to closely match adult exposures, and a weight-based oral dose may be more appropriate for children than a fixed dose. Safety of voriconazole in children was consistent with the known safety profile of voriconazole.

Purpose Acute graft-versus-host disease (GVHD) causes substantial morbidity and mortality after human leukocyte antigen (HLA)-identical sibling transplants. No large registry studies of acute GVHD risk factors have been reported in two decades. Risk factors may have changed in this interval as transplant-related techniques have evolved. Patients and Methods Acute GVHD risk factors were analyzed in 1,960 adults after HLA-identical sibling myeloablative transplant for acute myeloid leukemia (AML), acute lymphocytic leukemia (ALL), or chronic myeloid leukemia (CML) reported by 226 centers worldwide to the Center for International Blood and Marrow Transplant Research from 1995 to 2002. Outcome was measured as time from transplant to onset of grade 2 to 4 acute GVHD, with death without acute GVHD as a competing risk. Results Cumulative incidence of grade 2 to 4 acute GVHD was 35% (95% CI, 33% to 37%). In multivariable analyses, factors significantly associated with grade 2 to 4 acute GVHD were cyclophosphamide + total-body irradiation versus busulfan + cyclophosphamide (relative risk [RR] = 1.4; P < .0001), blood cell versus bone marrow grafts in patients age 18 to 39 years (RR = 1.43; P = .0023), recipient age 40 and older versus age 18 to 39 years receiving bone marrow grafts (RR = 1.44; P = .0005), CML versus AML/ALL (RR = 1.35; P = .0003), white/Black versus Asian/Hispanic race (RR = 1.54; P = .0003), Karnofsky performance score less than 90 versus 90 to 100 (RR = 1.27; P = .014), and recipient/donor cytomegalovirus-seronegative versus either positive (RR = 1.20; P = .04). Stratification by disease showed the same significant predictors of grade 2 to 4 acute GVHD for CML; however, KPS and cytomegalovirus serostatus were not significant predictors for AML/ALL. Conclusion This analysis confirmed several previously reported risk factors for grade 2 to 4 acute GVHD. However, several new factors were identified whereas others are no longer significant. These new data may facilitate individualized risk estimates and raise several interesting biologic questions.

A prospective multicenter trial was conducted to evaluate the safety and feasibility of granulocyte colony-stimulating factor (G-CSF)–primed bone marrow (G-BM) in children receiving allogeneic bone marrow transplantation (BMT). A total of 42 children with a median age of 9.8 years (range, 0.8-17 years) were enrolled. Donors with median age of 9.2 years (range, 1.1-22 years) received 5 μg/kg per day of subcutaneous G-CSF for 5 consecutive days. BM was harvested on the fifth day. No donor experienced complications related to G-CSF administration or marrow har-vest. Median nucleated (NC) and CD34 cells infused was 6.7 × 108/kg (range, 2.4-18.5 × 108/kg) and 7.4 × 106/kg (range, 2-27.6 × 106/kg), respectively. Neutrophil and platelet engraftment was at a median of 19 days (range, 13-28 days) and 20 days (range, 9-44 days), respectively. A total of 13 (32%) patients developed grade 2 graft-versus-host disease (GVHD), and 5 (13%) of 40 evaluable patients developed chronic GVHD (3 limited and 2 extensive). Higher cell dose was not associated with increased risk of acute or chronic GVHD. Overall survival and event-free survival at 2 years were 81% and 69%, respectively. Collection of G-BM from pediatric donors is safe, and can result in high NC and CD34 cell doses that facilitate engraftment after myeloablative BMT without a discernable increase in the risk of GVHD.