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Pilot Study of T-APCs Following CAR T Cell Immunotherapy for CD19+ Leukemia

Phase 1
Active, not recruiting
Conditions
CD 19+ Acute Leukemia
Interventions
Biological: T-cell Antigen Presenting Cells expressing truncated CD19 (T-APC)
Registration Number
NCT03186118
Lead Sponsor
Seattle Children's Hospital
Brief Summary

Patients with relapsed or refractory CD 19+ leukemia who have achieved remission after CD19 CAR-T cell treatment sometimes relapse because the CD 19 CAR-T cells decrease in number over time. Study PLAT-03 will test whether administering T cell antigen presenting cells (T-APCs) at intervals following treatment with CAR-T cells improves CD 19 CAR-T cell persistence and reduces the incidence of leukemia relapse.

Detailed Description

This pilot study seeks to examine the feasibility and safety of administering T cell antigen presenting cells (T-APCs) designed to reactivate and numerically expand CD19-specific CAR T cells. The underlying hypothesis to be examined is that after remission is achieved with CAR T cell treatment, the duration, magnitude, and activation state of persisting memory CAR T cells impact on the potential for durable leukemia eradication. This is of particular relevance in two groups of patients we have identified: those who are predicted to lose persistence of their CAR T cells before Day 63, and those who have definitively lost persistence of CAR T cells prior to 6 months. By providing these patients with episodic exposure to T-APCs capable of activating CD19-specific CAR T cells for proliferation and redistribution to tissue beds where tumor cells of ALL seed, ideally over several months following remission induction, it is posited that the incidence of disease relapse will be diminished.

Recruitment & Eligibility

Status
ACTIVE_NOT_RECRUITING
Sex
All
Target Recruitment
30
Inclusion Criteria
  • Diagnosis of recurrent or refractory CD19+ leukemia
  • Adequate performance status
  • Able to tolerate apheresis, including placement of temporary apheresis line if required
  • Adequate renal, liver, cardiac, and respiratory function
  • Adequate absolute lymphocyte count
  • HIV negative; Hepatitis B and C negative within 3 months prior to enrollment.
Exclusion Criteria
  • Evidence of active clinically significant CNS dysfunction
  • Evidence of active malignancy other than CD19+ malignancy
  • Evidence of active GVHD, or on immunosuppressive GVHD therapy within 4 weeks prior to enrollment

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Cohort AT-cell Antigen Presenting Cells expressing truncated CD19 (T-APC)Participants will receive CD19-targeting CAR T cells. Participants who have a total CD19 antigen load in bone marrow of \<15% will be assigned to Cohort A, to receive up to 6 T-APC treatments.
Cohort CT-cell Antigen Presenting Cells expressing truncated CD19 (T-APC)Participants will receive CD19-targeting CAR T cells. Participants for whom laboratory testing shows loss of CAR T cells within 6 months will be assigned to Cohort C. They will receive another CAR T cell infusion followed by up to 6 T-APC treatments.
Cohort DT-cell Antigen Presenting Cells expressing truncated CD19 (T-APC)Participants will receive CD19-targeting CAR T cells. Participants who do not meet assignment rules for Cohorts A, B, or C will be followed after CAR T cell infusion in Cohort D.
Cohort BT-cell Antigen Presenting Cells expressing truncated CD19 (T-APC)Participants will receive CD19-targeting CAR T cells. Participants for whom laboratory testing on Study Day 14 indicates they are at risk for early loss of CAR T cells will be assigned to Cohort B to receive up to 6 T-APC treatments. If laboratory testing prior to planned T-APC treatment indicates loss of CAR-T cells, participants may move to Cohort C.
Primary Outcome Measures
NameTimeMethod
The adverse events associated with one or multiple CD19t T-APC product infusions will be assessed.up to 6 months

Type, frequency, severity, and duration of adverse events will be summarized

Determine the feasibility of deriving and administering a CD19t T-APC product28 days

Proportion of products successfully manufactured and infused

Secondary Outcome Measures
NameTimeMethod
Quantification of changes in the number of CAR T cells in peripheral blood before and after receiving CD19t T-APCs6 months

Multiparameter Flow Cytometry (MPF) from peripheral blood as a measure of magnitude and presence of CAR T cells before and after a dose of T-APCs

Duration of B cell aplasia in CD19t T-APC treated patientsup to 5 years

MPF from peripheral blood as a measure of B cell aplasia

Trial Locations

Locations (1)

Seattle Children's Hospital

🇺🇸

Seattle, Washington, United States

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