Chimeric Antigen Receptor T Cell Redirected to Target CD4 Positive Relapsed Refractory Acute Myeloid Leukemia (AML ) as a Bridge to Allogeneic Stem Cell Transplant

Acute Myeloid Leukemia Clinical Trial

Official title: Chimeric Antigen Receptor T Cell Redirected to Target CD4 Positive Relapsed Refractory AML as a Bridge to Allogeneic Stem Cell Transplant

Status Recruiting

Clinical Trial Summary

This study is designed as a single arm open label traditional Phase I, 3+3, study of CD4-redirected chimeric antigen receptor engineered T-cells (CD4CAR) in patients with relapsed or refractory AML. the study will evaluate safety in this patient population and also the presence of efficacy signal described by elimination of residual disease to qualify patients for stem cell transplant.

Clinical Trial Description

The study will be performed as a dose-escalation protocol. The investigators expect to recruit 20 subjects at Indiana University with an expected dropout rate of 25% primarily due to rapid progression or death and screen and or manufacturing failure. Taking this into account, the investigators expect to treat 15 patients. The study will utilize autologous CD4CAR T-cells that are engineered to express a chimeric antigen receptor (CAR) targeting CD4 that is linked to the cluster of differentiation 28 (CD28), 4-1BB, cluster of differentiation 3-zeta (CD3ζ) signaling chains (third generation CAR). about 70% of AML with monocytic differentiation and 37% of all the rest express CD4 on their blasts.

At entry, disease status will be staged. Qualifying subjects will be leukapheresed to obtain large numbers of peripheral blood mononuclear cells (PBMC) for the manufacturing. Next, participants will receive conditioning chemotherapy. If tumor burden is sufficiently reduced (screening step), participants will receive CD4CAR cells by infusion on Day 0 of treatment.

If the disease progresses during the manufacturing period participants may be excluded from the study or an attempt to bridge for disease control will be offered. Minimal chemotherapy to keep the disease under control in the meanwhile is allowed if deemed necessary by investigators.

A single dose of CD4CAR transduced T cells will consist of the cell number for the dose level to be infused.

Post-infusion monitoring of CD4CAR T-cells: Subjects will have blood drawn for cytokine levels, CD4CAR Transgene Copy Number (PCR) and flow cytometry in order to evaluate the presence of CD4CAR cells on days 0, 1, 3, 5, 7, 14, and 28 following infusion (or as clinically needed). Cytokines levels will be evaluated per schedule above in addition to and as needed every 8 +/- 2 hours as feasible if/when Cytokine Release Syndrome, CRS, occurs and until resolution. Active monitoring of fungal and viral infections during treatment while utilizing standard prophylaxis recommended for HIV-positive patients with T-cell aplasia and those undergoing allogeneic stem cell transplant. Investigators plan to collect data about clinicoradiologic measurements of residual tumor burden starting on day 7 and weekly afterward until Day 28 and then monthly for 6 months. This will be followed by quarterly clinical evaluations for the next two (2) years with a medical history, physical examination, and comprehensive blood testing. After these short- and intermediate-term evaluations are performed, these patients will enter a rollover study to assess for disease-free survival (DFS), relapse, and the development of other health problems or malignancies where follow-up will be up to twice a year by phone and a questionnaire for an additional thirteen (13) years. The treating physician will decide to proceed with allogeneic or autologous transplant when needed.

Dose of CD4CAR description: the main objective of this study is to establish a recommended dose and/or schedule of CD4CAR. The guiding principle for dose escalation in phase I is to avoid unnecessary exposure of patients to sub-therapeutic doses (i.e., to treat as many patients as possible within the therapeutic dose range) while preserving safety and maintaining rapid accrual. Investigators will use the rule-based traditional Phase I "3+3" design for the evaluation of safety. Based on lab experience in mice the starting dose (dose level 1) for the first cohort of three patients in phase I portion of the study will be 8x10^5 cells. The dose escalation or de-escalation will follow a modified Fibonacci sequence as below.

If more than one patient out of the first cohort of three patients in dose level 1 experience dose limiting toxicity (DLT), the trial will be placed on hold. If zero or one out of three patients in the first cohort of dose level 1 experience DLT, three more patients will be enrolled at dose level 1; the dose escalation continues until at least two patients among a cohort of six patients experience DLT (i.e., ≥33% of patients with a DLT at this dose level)

If one of the first three patients in dose level 1 experiences a DLT, three more patients will be treated at dose level 1.

If none of the three patients or only one of the 6 patients in the dose level 1 experiences a DLT, the dose escalation continues to the dose level 2 If one of the first three patients in dose level 2 experience a DLT, three more patients will be treated at dose level 2 If none of the three patients or only one of the 6 patients in the dose level2 experiences a DLT, the dose escalation continues to the dose level 3 If one of the first three patients in dose level 3 experiences a DLT, three more patients will be treated at dose level 3 If none of the three patients or only one of the 6 patients in the dose level 3 experiences a DLT, dose level 3 will be declared the maximum tolerated dose (MTD) and will be used as the recommended phase II dose (RP2D) for the phase II portion of the study.

In summary, the dose escalation continues until at least two patients among a cohort of six patients experience DLT (i.e., ≥33% of patients with a DLT at that dose level). The recommended dose for phase II trials is defined as one dose level below this toxic dose level. Since some grade 3 and possibly 4 toxicities are highly likely to be reversible, grade 3 infectious, hematological and vascular toxicities will not be considered DLTs mandating dose reduction. Also allergic or infusion-related reactions ≤ grade 3 will not be counted as DLTs. There will be no intra-patient dose escalation or reduction.

To allow for full spectrum toxicity duration evaluation and reporting, no patients within the same or a different cohort will be initiated on lymphodepleting chemotherapy sooner than 28 days from the initiation date of the preceding patient. ;

Related Conditions & MeSH terms

• Acute Myeloid Leukemia
• Leukemia
• Leukemia, Myeloid
• Leukemia, Myeloid, Acute

• NCT number: NCT06197672
• Study type: Interventional
• Source: Indiana University
• Contact: Tara Haney, RN
• Phone: 317-278-4184
• Email: tnhaney@iu.edu
• Status: Recruiting
• Phase: Phase 1
• Start date: March 19, 2024
• Completion date: December 31, 2042