CD19-CD22-Bispecific Chimeric Antigen Receptor (CAR) T Cell Therapy for Pediatric Patients With Acute Lymphoblastic Leukemia

This study is a phase I study designed to evaluate the safety of CD19-CD22-CAR T cells.

Primary Objective:

To determine the safety profile and propose the recommended phase 2 dose (RP2D) of autologous CD19-CD22-CAR T cells in patients ≤ 21 years of age with recurrent/refractory CD19- and/or CD22-positive leukemia.

Secondary Objective:

To evaluate the anti-leukemic activity of CD19-CD22-CAR T cells.

Treatment will include a single course of lymphodepleting chemotherapy (fludarabine/cyclophosphamide) followed by CAR T cell infusion. CAR T cell dose will be determined by the protocol-defined dose escalation scheme, based on the number of CAR+ T cells and participant weight.

Eligibility Criteria:
Collection and Manufacturing Eligibility

Inclusion Criteria:

* Age \<21 years old
* Relapsed/refractory CD19- and/or CD22-positive acute leukemia defined as:

  \*CD19 and/or CD22-positivity confirmed within 2 months and after receipt of any CD19 or CD22-directed therapy
  * Second or greater relapse
  * Any relapse after allogeneic HCT
  * Refractory disease (primary or in relapse) despite therapy designed to induce remission
* Estimated life expectancy of \> 12 weeks
* Karnofsky or Lansky (age-dependent) performance score ≥50 (Appendix A)
* For females of childbearing age:

  * Not lactating with intent to breastfeed
  * Not pregnant with negative serum or urine pregnancy test within 7 days prior to enrollment

Exclusion Criteria:

* Known primary immunodeficiency
* Known HIV positivity
* Known contraindication to receiving protocol defined lymphodepleting
* chemotherapy regimen
* History of hypersensitivity reaction to murine-containing products

Treatment Eligibility

Inclusion Criteria:

* Age \< 21 years old
* Detectable CD19- and/or CD22-positive leukemic disease in the bone marrow
* Estimated life expectancy of \> 8 weeks
* Karnofsky or Lansky (age-dependent) performance score \> 50 (Appendix A)
* Adequate cardiac function defined as left ventricular ejection fraction \>40%, or shortening fraction \> 25%
* EKG without evidence of clinically significant arrhythmia
* Adequate renal function defined as creatinine clearance or radioisotope GFR \>50 mL/min/1.73m2 (GFR \>40 mL/min/1.73m2 if \<2 years of age)
* Adequate pulmonary function defined as forced vital capacity (FVC) \>50% of predicted value; or pulse oximetry \>92% on room air
* Total bilirubin \< 3 times the upper limit of normal for age, except in subjects with Gilbert's syndrome
* Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) \< 5 times the upper limit of normal for age
* Has recovered from all NCI CTAE grade III-IV, non-hematologic acute toxicities from prior therapy
* Prior to planned CAR T cell infusion, patients with a history of prior allogeneicHCT must be at least 3 months from HCT, have no evidence of acute GVHD, and have not received a donor lymphocyte infusion (DLI) within the 28 daysprior to planned infusion
* For females of childbearing age:

  * Not lactating with intent to breastfeed
  * Not pregnant with negative serum or urine pregnancy test within 7 days prior to enrollment
  * If sexually active, agreement to use birth control until 3 months after T cell infusion. Male partners should use a condom.

Exclusion Criteria:

* Known primary immunodeficiency
* Known HIV positivity
* Known contraindication to receiving protocol defined lymphodepleting
* chemotherapy regimen
* History of hypersensitivity reactions to murine protein-containing products
* Severe, uncontrolled bacterial, viral or fungal infection
* Active CNS-3 disease
* Evidence of active, uncontrolled neurologic disease