Jasper Therapeutics Research Articles

2098. Cytomegalovirus (CMV) Infection Following Hematopoietic Cell Transplantation (HCT) with Post-transplant Cyclophosphamide (PTCy): Outcomes in Haploidentical versus Matched or Mismatched Unrelated Donor (MUD/MMURD) Allografts

Abstract Background PTCy is increasingly being used in MUD/MMURD, and haploidentical donor HCT for prevention of graft-versus-host disease (GVHD). PTCy has been associated with increased risk of infections including CMV viremia after HCT. It remains unclear if this observation is independent of graft type. This study aims to evaluate the incidence of clinically significant CMV infection (CS-CMVi) following PTCy in MUD/MMURD compared to haploidentical donor HCT. Methods We performed a single-center retrospective study of all adults undergoing HCT with PTCy between January 1, 2015 and July 1, 2021. CS-CMVi, defined as CMV viremia or disease requiring initiation of CMV therapy, was evaluated in two groups: haploidentical HCT (n=170) and MUD/MMURD HCT (n=137). We assessed the incidence of CMV viremia, CS-CMVi, and CMV disease, as well as incidence of letermovir breakthrough infections and late CMV events after cessation of prophylaxis. Cumulative Incidence Functions were calculated based on time to CS-CMVi using dates of infection-free death, disease relapse, and repeat HCT as competing risks. Results The one-year cumulative incidence of CS-CMVi accounting for competing risks was 25% (95% CI 19 – 32) in the haploidentical group and 18% (95% CI 12 – 25) in the MUD/MMURD group (HR 1.50; 95% CI 0.91 – 2.46; p=0.11). CMV disease was rare, (haploidentical n=1; MUD/MMURD n=1) and no patients died of CMV infection. CS-CMVi in CMV seropositive patients was more common in the haploidentical group (23% versus 9%; p=0.002). Notably, CMV D+/R- HCT patients had a significantly higher rate of CS-CMVi in the MUD/MMURD cohort than in the haploidentical cohort. Of the CS-CMVi, letermovir breakthrough constituted 26% in the haploidentical group and 29% in the MUD/MMURD group. Late infections after cessation of letermovir occurred in only 14% of cases in the haploidentical group and 25% of cases in the MUD/MMURD group. Conclusion Rates of CS-CMVi, CMV viremia, and CMV disease were similar following PTCy in haploidentical donor HCT and MUD/MMURD HCT. CS-CMVi in CMV seropositive patients was more common in the haploidentical donor HCT population and MUD/MMURD HCT recipients had a higher incidence of CS-CMVi in the D+/R- patients. Disclosures Roman M. Shapiro, M.D., Miltenyi Biotec: Honoraria Rizwan Romee, M.D., Crispr Therapeutics: Grant/Research Support|Glycostem Therapeutics: Advisor/Consultant|NK Therapeutics: Advisor/Consultant|Skyline Therapeutics: Grant/Research Support Robert J. Soiffer, M.D., CSL Behring: Advisor/Consultant|Gilead: Career Chair Development Award|Jasper Therapeutics: Advisor/Consultant|Jazz Pharmaceuticals: Advisor/Consultant|Juno (BMS): DSMB|Kiadis: Board Member|Vor: Advisor/Consultant Vincent T. T. Ho, M.D., Alexion Pharmaceuticals: Advisor/Consultant|Allovir: Advisor/Consultant|Allovir: DSMC|Jazz Pharmaceuticals: Grant/Research Support|Omeros: Advisor/Consultant Nicolas C. Issa, MD, AiCuris: Grant/Research Support|Merck: Grant/Research Support.

JSP191 As a Single-Agent Conditioning Regimen Results in Successful Engraftment, Donor Myeloid Chimerism, and Production of Donor Derived Naïve Lymphocytes in Patients with Severe Combined Immunodeficiency (SCID)

JSP191 As a Single-Agent Conditioning Regimen Results in Successful Engraftment, Donor Myeloid Chimerism, and Production of Donor Derived Naïve Lymphocytes in Patients with Severe Combined Immunodeficiency (SCID)

A Phase 1 Study Evaluating ASTX727 (decitabine and cedazuridine) and Venetoclax Combination Therapy in Newly Diagnosed AML Patients Unfit for Intensive Induction Chemotherapy

A Phase 1 Study Evaluating ASTX727 (decitabine and cedazuridine) and Venetoclax Combination Therapy in Newly Diagnosed AML Patients Unfit for Intensive Induction Chemotherapy

Anti-CD117 CAR T Cells Incorporating a Safety Switch Eradicate Acute Myeloid Leukemia and Deplete Human Hematopoietic Stem Cells

Anti-CD117 CAR T Cells Incorporating a Safety Switch Eradicate Acute Myeloid Leukemia and Deplete Human Hematopoietic Stem Cells

KMT2A Rearrangements Are Associated with Lineage Switch Following CD19 Targeting CAR T-Cell Therapy

KMT2A Rearrangements Are Associated with Lineage Switch Following CD19 Targeting CAR T-Cell Therapy

Safety and Efficacy from a Phase 1b/2 Study of IMGN632 in Combination with Azacitidine and Venetoclax for Patients with CD123-Positive Acute Myeloid Leukemia

Safety and Efficacy from a Phase 1b/2 Study of IMGN632 in Combination with Azacitidine and Venetoclax for Patients with CD123-Positive Acute Myeloid Leukemia

Impact of Allogeneic Hematopoietic Cell Transplantation (HCT) As Consolidation Following CD19 Chimeric Antigen Receptor (CAR) T Cell Therapy for Treatment of Relapsed Acute Lymphoblastic Leukemia (ALL)

Impact of Allogeneic Hematopoietic Cell Transplantation (HCT) As Consolidation Following CD19 Chimeric Antigen Receptor (CAR) T Cell Therapy for Treatment of Relapsed Acute Lymphoblastic Leukemia (ALL)

Long-Term Overall Survival (OS) with Oral Azacitidine (Oral-AZA) in Patients with Acute Myeloid Leukemia (AML) in First Remission after Intensive Chemotherapy (IC): Updated Results from the Phase 3 QUAZAR AML-001 Trial

Long-Term Overall Survival (OS) with Oral Azacitidine (Oral-AZA) in Patients with Acute Myeloid Leukemia (AML) in First Remission after Intensive Chemotherapy (IC): Updated Results from the Phase 3 QUAZAR AML-001 Trial

Safety and Efficacy of Lower Intensity Induction Therapy with Intravenous Prexigebersen (BP1001) in Patients with High-Risk and Relapsed/Refractory Acute Myeloid Leukemia (AML)

Safety and Efficacy of Lower Intensity Induction Therapy with Intravenous Prexigebersen (BP1001) in Patients with High-Risk and Relapsed/Refractory Acute Myeloid Leukemia (AML)

Treatment Patterns and Survival Outcomes of Patients with Acute Myeloid Leukemia Who Achieved Remission in the Connect ® Myeloid Disease Registry

Treatment Patterns and Survival Outcomes of Patients with Acute Myeloid Leukemia Who Achieved Remission in the Connect ® Myeloid Disease Registry

Heterogeneity of Minimal/Measurable Residual Disease (MRD) Practices in Adult B-Cell Precursor Acute Lymphoblastic Leukemia (BCP-ALL) in the United States

Background: MRD testing in BCP-ALL is critical for appropriate patient management, but little is known regarding sample acquisition and testing heterogeneity across clinical practice settings. These factors may impact the quality and reliability of MRD assessment.Methods: Thirty-minute online surveys were conducted in May 2021 with hematologists/oncologists (HEME/ONCs) in the United States in both academic (acad) and community (comm) settings. Respondents were licensed physicians board certified in oncology and/or hematology who treated ≥2 BCP-ALL patients/year or ≥10 patients in the past 5 years, with over 25% of time spent in the clinical setting; pediatric HEME/ONCs were excluded. Survey enrollment is ongoing, with interim results presented here; a related survey for pathologists (PATHs) is underway.Results: HEME/ONC respondents (acad n=40, comm n=57, from 29 states) had been practicing as specialists for a median of between 11-15 years (choices were ranges, eg 6-10, 11-15, min-max was 1-34 years), and typically spent over 75% of their time in the clinic; 94% of respondents had ≥5 BCP-ALL patients/year and 92% ordered MRD tests for ≥5 patients/year. Typical timepoints for MRD testing included the end of induction/suspected complete remission, the end of consolidation, and at suspected disease progression; testing after the end of consolidation was infrequent in both groups (Table). Testing for MRD at the end of consolidation was notably more frequent in the academic setting. In both settings, the HEME/ONC ordering the MRD test generally also performed the bone marrow collection procedure (acad: 78%, comm: 56%). Resources consulted on bone marrow collection best practices included UpToDate (21%), ASH and ASCO (13%), NCCN guidelines (13%), and hematology/oncology journals. About half of practices had defined institutional protocols for bone marrow collection (acad: 55%, comm: 47%), nearly all of which were developed internally. The amount of bone marrow sample collected showed high variability, ranging from 1-10 draws (median=3) and 1-30 mL sample per draw (median=5 mL). While 49% of HEME/ONCs performed <5 draws and extracted ≤6 mL per draw, 22% collected 10 mL/draw, and 10% collected 20 mL/draw; the remaining 18% reported >5 draws and/or >6 mL per draw. In both settings, the first pull was identified and labeled in 35% of procedures; in those cases, the first-pull samples were used primarily for MRD testing in 60% of cases as recommended by NCCN guidelines (vs for morphology assessment and cytogenetic studies). HEME/ONCs typically relied on the expertise of pathologists to choose MRD testing methodology.Survey results indicate that external labs (both national clinical reference labs and commercial labs) were most commonly used for MRD assessments (63%); comm HEME/ONCs were more likely to use external reference labs and acad HEME/ONCs were more likely to use in-house labs. When asked to estimate the frequency with which different MRD methods were used, mean responses were 54% flow cytometry and 40% next-generation sequencing. While all HEME/ONCs indicated that MRD results were presented clearly in lab reports, there was a desire to include more guideline information about MRD interpretation and BCP-ALL treatment.Conclusion: Interim results identified broad heterogeneity in clinical practices affecting sample collection for MRD assessment in Ph- BCP-ALL in the US, indicating several opportunities for harmonization of routine MRD assessment in BCP-ALL. These opportunities include optimization of bone marrow sample collection techniques (volume/draw and identification/use of first pull for MRD), timing/frequency of specimen collection, serial MRD surveillance after consolidation, MRD method chosen, and standardizing reports to include guideline information. There were gaps in awareness of FDA-approved methods of MRD testing for BCP-ALL. Initiatives supporting provider education and harmonization of best practices from professional guideline committees/organizations are needed to optimize outcomes of BCP-ALL patients. [Display omitted] DisclosuresHidalgo-Lopez: Amgen Inc.: Current Employment, Current holder of stock options in a privately-held company. Roboz: Janssen: Research Funding; Daiichi Sankyo: Consultancy; MEI Pharma - IDMC Chair: Consultancy; Actinium: Consultancy; AbbVie: Consultancy; Mesoblast: Consultancy; Bayer: Consultancy; Blueprint Medicines: Consultancy; Jazz: Consultancy; Janssen: Consultancy; Astex: Consultancy; Celgene: Consultancy; Bristol Myers Squibb: Consultancy; Agios: Consultancy; Astellas: Consultancy; Jasper Therapeutics: Consultancy; Helsinn: Consultancy; Glaxo SmithKline: Consultancy; Novartis: Consultancy; Amgen: Consultancy; AstraZeneca: Consultancy; Otsuka: Consultancy; Pfizer: Consultancy; Roche/Genentech: Consultancy. Wood: Pfizer, Amgen, Seattle Genetics: Honoraria; Juno, Pfizer, Amgen, Seattle Genetics: Other: Laboratory Services Agreement. Borowitz: Amgen, Blueprint Medicines: Honoraria. Jabbour: Amgen, AbbVie, Spectrum, BMS, Takeda, Pfizer, Adaptive, Genentech: Research Funding. Velasco: Amgen Inc.: Current Employment, Current holder of stock options in a privately-held company. Elkhouly: Amgen Inc.: Current Employment, Current holder of stock options in a privately-held company. Adedokun: Amgen Inc.: Current Employment, Current holder of stock options in a privately-held company. Zaman: Amgen Inc.: Current Employment, Current holder of stock options in a privately-held company. Iskander: Amgen Inc.: Current Employment, Current holder of stock options in a privately-held company. Logan: Amgen, Pfizer, AbbVie: Consultancy; Pharmacyclics, Astellas, Jazz, Kite, Kadmon, Autolus, Amphivena: Research Funding.

Long Term Follow-up and Combined Phase 2 Results of Eprenetapopt (APR-246) and Azacitidine (AZA) in Patients with TP53 mutant Myelodysplastic Syndromes (MDS) and Oligoblastic Acute Myeloid Leukemia (AML)

Long Term Follow-up and Combined Phase 2 Results of Eprenetapopt (APR-246) and Azacitidine (AZA) in Patients with TP53 mutant Myelodysplastic Syndromes (MDS) and Oligoblastic Acute Myeloid Leukemia (AML)

Aspacytarabine (BST-236) As Monotherapy Is Safe, Well-Tolerated and Effective for the Treatment of Adults with Newly Diagnosed Acute Myeloid Leukemia Unfit for Intensive Therapy. Results of a Phase 2 Study

Aspacytarabine (BST-236) As Monotherapy Is Safe, Well-Tolerated and Effective for the Treatment of Adults with Newly Diagnosed Acute Myeloid Leukemia Unfit for Intensive Therapy. Results of a Phase 2 Study

Prognostic Impact of NPM1 and FLT3 Mutations at Diagnosis and Presence of Measurable Residual Disease (MRD) after Intensive Chemotherapy (IC) for Patients with Acute Myeloid Leukemia (AML) in Remission: Outcomes from the QUAZAR AML-001 Trial of Oral Azacitidine (Oral-AZA) Maintenance

Prognostic Impact of NPM1 and FLT3 Mutations at Diagnosis and Presence of Measurable Residual Disease (MRD) after Intensive Chemotherapy (IC) for Patients with Acute Myeloid Leukemia (AML) in Remission: Outcomes from the QUAZAR AML-001 Trial of Oral Azacitidine (Oral-AZA) Maintenance

Mgta-145 + Plerixafor Provides GCSF-Free Rapid and Reliable Hematopoietic Stem Cell Mobilization for Autologous Stem Cell Transplant in Patients with Multiple Myeloma: A Phase 2 Study

Mgta-145 + Plerixafor Provides GCSF-Free Rapid and Reliable Hematopoietic Stem Cell Mobilization for Autologous Stem Cell Transplant in Patients with Multiple Myeloma: A Phase 2 Study

Phase I and Expansion Study of Eprenetapopt (APR-246) in Combination with Venetoclax (VEN) and Azacitidine (AZA) in TP53-Mutant Acute Myeloid Leukemia (AML)

Phase I and Expansion Study of Eprenetapopt (APR-246) in Combination with Venetoclax (VEN) and Azacitidine (AZA) in TP53-Mutant Acute Myeloid Leukemia (AML)

Clinical Predictors of Outcome in Adult Patients with Acute Leukemias and Myelodysplastic Syndrome and COVID-19 Infection: Report from the American Society of Hematology Research Collaborative (ASH RC) Data Hub

Clinical Predictors of Outcome in Adult Patients with Acute Leukemias and Myelodysplastic Syndrome and COVID-19 Infection: Report from the American Society of Hematology Research Collaborative (ASH RC) Data Hub

SCRI-CAR19x22v2 T Cell Product Demonstrates Bispecific Activity in B-ALL

Introduction: CAR T cells in B-ALL have recently focused on the dual targeting of CD19 and CD22 to enhance long term remissions and prevent antigen negative recurrence that is frequently encountered with single antigen targeting. However, a barrier to this approach has been the retention of dual specificity killing and ongoing persistence. PLAT-05 is a multisite phase 1 trial (NCT03330691) that was undertaken to evaluate the safety and feasibility of SCRI-CAR19x22v1, a dual transduced patient-derived product with lentiviral vectors encoding for either a CD19- or CD22-specific CAR, both with 4-1BB co-stimulation. Early results of the first 27 subjects infused demonstrated feasibility and a favorable safety profile with encouraging CR rates. Products were fractionated evenly between CD19 CAR, CD19+CD22 CAR and CD22 CAR. However, engraftment was predominated by the single CD19 CAR population, leading to unsuccessful eradication of CD19-CD22+ leukemia. This finding led to re-engineering the CD22 CAR construct for enhanced CD22 targeting, and re-initiation of dose finding with the new product, SCRI-CAR19v2.Methods: After enrollment, subjects undergo apheresis followed by a combined CD4/CD8 positive immunomagnetic selection and seeded at a prescribed ratio for co-culture in a closed-system G-Rex bioreactor. Following anti-CD3xCD28 bead stimulation, T cells are transduced with two lentiviral vectors that encode for either a CD19- or CD22-specific CAR. After flu/cy lymphodepletion, CAR T cells are infused at one of three dose levels: 0.5, 1 or 3 X 10 6 CAR T cells/kg. Toxicity is graded according to CTCAEv5 except for CRS and ICANS which are graded per ASTCT criteria. Leukemic response and CAR T cell persistence are evaluated by flow cytometry.Results: 14 subjects enrolled onto PLAT-05 for the SCRI-CAR19x22v2 dose escalation and products were successfully manufactured in all subjects with an average of 8.9 days in culture (range 7-12 days). In contrast to v1 products, the CAR composition of v2 products was skewed in favor of CD22 CAR expression, with median expression of each population as follows: 42% CD22 only, 33% CD19 and CD22, 3.2% CD19 only. Twelve subjects were infused (0.5x10 6/kg n=3, 1x10 6/kg n=3, 3x10 6/kg n=6), 11 of whom had prior exposure to CD19 or CD22 targeted therapies with diverse expression of CD19 and CD22 on the leukemic blasts. No dose limiting toxicities occurred in the 11 fully evaluable subjects (1 subject is pending) and the recommended phase 2 dose was determined as 3x10 6 CAR + cells/kg. CRS was present in 45% of subjects, all grade 1. Neurotoxicity occurred in 45% of subjects, all grade 1 except a single self-limited grade 3 ICANS event (due to a single time point CAPD score). 91% of infused subjects obtained a CR, of which 100% were MRD negative. The non-responder had persistent disease that was CD19-CD22-. The in vivo engraftment of CAR T cells peaked most frequently between day +7 and +14 and was predominated by the CD22 CAR T cells, with some minimal contribution of dual and CD19 CAR T cells. Of the 4 subjects who had previously received an FMC63 based CD19 CAR, expansion was due to solely to the CD22 CARs in all 4 subjects, with apparent rejection of the T cells expressing CD19 CAR.Conclusions: We demonstrate enhanced activity of SCRI-CAR19x22v2 compared to v1, now with dual activity against both CD19 and CD22 demonstrated by elimination of ALL with single antigen expression. We maintained encouraging CR rates with a favorable toxicity profile. Interestingly, the product is predominated by CD22 CAR and CD19/CD22 CAR populations, while in vivo engraftment is predominated by single CD22 CAR expressing T cells. Subjects exposed to prior CD19 murine based CAR rejected the CD19 CAR but engrafted the CD22 CAR with demonstratable activity, a potential advantage of a dual transduced product. The impact of lower CD19 CAR engraftment on durable remissions is unknown. While limited expansion of the CD19 CAR population could be protective against exhaustion, the uneven engraftment of the CAR populations may ultimately lead to single antigen targeting. Optimization of transduction may be required for a more balanced product to maintain dual targeting and give further insight into the behavior of dual-expressing CAR T cells. An expansion cohort is currently underway to further characterize engraftment kinetics and in vivo performance to best inform future development of this product. [Display omitted] DisclosuresPulsipher: Jasper Therapeutics: Honoraria; Adaptive: Research Funding; Equillium: Membership on an entity's Board of Directors or advisory committees. Li: Novartis Canada: Membership on an entity's Board of Directors or advisory committees. Jensen: Bluebird Bio: Research Funding; Umoja Biopharma: Current holder of stock options in a privately-held company, Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS: Patents & Royalties. Gardner: Novartis: Consultancy; BMS: Patents & Royalties. OffLabel Disclosure:investigational use of SCRI-CAR19x22 will be discussed

Final Results of a Phase 1b Study of BET Inhibitor PLX2853 in Patients with Relapsed or Refractory Acute Myeloid Leukemia or High Risk Myelodysplastic Syndrome

Final Results of a Phase 1b Study of BET Inhibitor PLX2853 in Patients with Relapsed or Refractory Acute Myeloid Leukemia or High Risk Myelodysplastic Syndrome

Peri-Transplant Alemtuzumab Levels Predict Risk of Secondary Graft Failure and Inversely Impact CXCL9 Levels after RIC HCT (A Correlative Biology Study to BMT-CTN 1204 RICHI)

Peri-Transplant Alemtuzumab Levels Predict Risk of Secondary Graft Failure and Inversely Impact CXCL9 Levels after RIC HCT (A Correlative Biology Study to BMT-CTN 1204 RICHI)