Erwinia asparaginase and venetoclax added to blinatumomab for relapsed/refractory CD19+ B‑ALL

A Phase 1/1b Study Evaluating Asparaginase Erwinia Chrysanthemi- Recombinant-Rywn (Recombinant Erwinia Asparaginase) and Venetoclax in Combination With Blinatumomab in Adults With Relapsed or Refractory B-Cell Acute Lymphoblastic Leukemia

Phase 1 Interventional City of Hope Medical Center · NCT07133997

This will test whether adding recombinant Erwinia asparaginase and venetoclax to blinatumomab helps adolescents and adults (12–55) with CD19-positive relapsed or refractory B-cell acute lymphoblastic leukemia.

Quick facts

PhasePhase 1
Study typeInterventional
Enrollment26 (estimated)
Ages12 Years to 55 Years
SexAll
SponsorCity of Hope Medical Center Academic / other
Drugs / interventionsrituximab, blinatumomab, chimeric antigen receptor, chemotherapy, Immunotherapy, methotrexate, cyclophosphamide, prednisone
Locations1 site (Duarte, California)
Trial IDNCT07133997 on ClinicalTrials.gov

What this trial studies

This Phase I/Ib trial combines recombinant Erwinia asparaginase and venetoclax with blinatumomab to determine safety, tolerability, and a recommended phase II schedule in patients aged 12–55 with CD19-positive relapsed or refractory B-ALL. Dose-escalation cohorts will monitor toxicities and treatment-limiting events, followed by an expansion phase to estimate anti-tumor activity measured by composite remission rates (CR/CRh/CRi). The protocol includes serial bone marrow assessments, MRD testing by flow cytometry and ClonoSeq, and exploratory correlative studies such as BH3 profiling and somatic mutation analysis. Transplant-eligible patients may be bridged directly from trial therapy to allogeneic hematopoietic stem cell transplant.

Who should consider this trial

Good fit: Ideal candidates are people aged 12–55 with CD19-positive relapsed or refractory B-ALL, ≥5% marrow blasts, ECOG ≤2 (or KPS ≥70), acceptable organ function per protocol, and a pre-treatment WBC <25×10^9/L or able to undergo cytoreduction.

Not a fit: Patients unlikely to benefit include those who are CD19-negative, have uncontrolled infections or severe organ dysfunction, have a history of life-threatening allergy to asparaginase or venetoclax, or are outside the 12–55 age range.

Why it matters

Potential benefit: If effective, the regimen could increase remission and MRD-negative rates and help more patients bridge to potentially curative stem cell transplant.

How similar studies have performed: Blinatumomab is established in R/R CD19+ ALL and early-phase reports combining venetoclax with other ALL therapies have shown encouraging responses, but the specific three-drug combination with recombinant Erwinia asparaginase is novel and less tested.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Documented informed consent of the participant and/or legally authorized representative
* Age between 12 and 55
* Eastern Cooperative Oncology Group (ECOG) ≤ 2 or Karnofsky performance status (KPS) ≥ 70
* Patients with relapsed or refractory (R/R) CD19 positive (+) B-cell acute lymphoblastic leukemia (B-ALL) according to World Health Organization (WHO) criteria

  * Greater than or equal to 5% blasts in the bone marrow
* White blood cell count less than 25 x 10\^9/L prior to initiation of venetoclax. (within 14 days prior to day 1 of protocol therapy) Cytoreduction with hydroxyurea, steroid or a single dose of cyclophosphamide chemotherapy prior to treatment may be required
* Total bilirubin ≤ 1.5 x upper limit of normal (ULN) (within 14 days prior to day 1 of protocol therapy) (unless has Gilbert's disease or underlying leukemia, ≤ 3 x ULN)
* Prothrombin time (PT) ≤ 1.5 ULN (within 14 days prior to day 1 of protocol therapy)
* Partial thromboplastin time (PTT) ≤ 1.5 ULN (within 14 days prior to day 1 of protocol therapy)
* Aspartate aminotransferase (AST) ≤ 2.5 x ULN (within 14 days prior to day 1 of protocol therapy) (Unless it is related to underlying leukemia, then AST ≤ 5 x ULN)
* Alanine aminotransferase (ALT) ≤ 2.5 x ULN (within 14 days prior to day 1 of protocol therapy) (Unless it is related to underlying leukemia, then ALT ≤ 5 x ULN)
* Creatinine clearance of ≥ 60 mL/min per 24 hour urine test or the Cockcroft-Gault formula (within 14 days prior to day 1 of protocol therapy)
* Left ventricular ejection fraction (LVEF) ≥ 50% (within 14 days prior to day 1 of protocol therapy)

  * Note: Echocardiogram to be performed within 42 days prior to day 1 of protocol therapy
* Women of childbearing potential (WOCBP): Negative urine or serum pregnancy test (within 14 days prior to day 1 of protocol therapy)

  * If the urine test is positive or cannot be confirmed as negative, a serum pregnancy test will be required
* Agreement by females and males of childbearing potential to use an effective method of birth control or abstain from heterosexual activity for the course of the study through at least 3 months after the last dose of protocol therapy

  * Childbearing potential defined as not being surgically sterilized (men and women) or have not been free from menses for \> 1 year (women only).

Exclusion Criteria:

* Allogeneic hematopoietic cell transplantation (HCT) within 8 weeks prior to the start of protocol-specific therapy. Subjects must be off all immunosuppression for ≥ 2 weeks
* Cancer chemotherapy within 2 weeks before the start of protocol-specified therapy with the exception of: intrathecal chemotherapy and/or low-dose maintenance therapy (e.g. vina alkaloids, mercaptopurine, methotrexate, or hydroxyurea etc)
* Strong and moderate CYP3A4 inducers and strong CYP3A inhibitors within 7 days prior to day 1 of protocol therapy
* Foods/supplements that are strong inhibitors or strong or moderate inducers of CYP3A (such as grapefruit, Seville oranges, starfruit and St. John's wort) within 3 days prior to initiation of and during study treatment
* Immunotherapy (e.g. rituximab) within 4 weeks before the start of protocol-specified therapy. Prior failed CD19-directed therapy such as prior blinatumomab or CD19-directed chimeric antigen receptor (CAR)-T cells will be allowed if treatment ended \> 4 weeks prior to start of protocol-specific therapy and there is demonstrated continued CD19+ expression
* Must not have received or planning to receive live vaccine while being on study or 2 weeks before and after completion of treatment
* Patients with any prior intolerance leading to discontinuation of pegylated (PEG)-asparaginase due to grade 3 or more pancreatitis or central nervous system thrombosis requiring anticoagulant treatment attributed to the PEG-asparaginase
* Active ALL in the central nervous system (CNS): Presence of \> 5 white blood cells (WBC) per cubic millimeter in the cerebrospinal fluid (CSF) with lymphoblasts present (confirmed by CSF analysis) and/or clinical signs of CNS leukemia. If CSF leukemia is present, subjects will need to receive intrathecal chemotherapy and have documented negative CSF prior to enrollment
* Active acute or chronic graft versus host disease requiring systemic treatment with immunosuppressive medication
* History of intracranial thrombosis or history of recurrent thrombosis or grade 3 and greater pulmonary embolism (except for catheter-related thrombosis)
* Participants with history of grade ≥ 3 pancreatitis
* History of alcohol overuse if deemed relevant in investigator's opinion
* Known hypersensitivity to blinatumomab/ recombinant Erwinia asparaginase or to any component of the product formulation, otherwise prior treatment with single agent blinatumomab is allowed
* Uncontrolled active infection
* Clinically significant uncontrolled illness or cirrhosis
* Other active malignancy (except superficial skin cancers squamous cell carcinoma \[SCC\]/basal cell carcinoma \[BCC\], early-stage malignancies ductal carcinoma in-situ \[DCIS\] status post \[s/p\] excision or elevated prostate specific antigen \[PSA\])
* Females only: Pregnant or breastfeeding
* Any other condition that would, in the investigator's judgment, contraindicate the patient's participation in the clinical study due to safety concerns with clinical study procedures
* Prospective participants who, in the opinion of the investigator, may not be able to comply with all study procedures (including compliance issues related to feasibility/logistics)

Where this trial is running

Duarte, California

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Recurrent B Acute Lymphoblastic LeukemiaRefractory B Acute Lymphoblastic Leukemia
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.