Clinical Study on the Safety and Efficacy of PID23 Injection in Patients With Relapsed/Refractory Acute Leukemia (R/R AL)

A Single-center, Single-arm, Open-label Clinical Study on the Safety and Efficacy of PID23 Injection in Treating Patients With Relapsed/Refractory Acute Leukemia

Relapsed or refractory acute leukemia (R/R AL) is a life-threatening blood cancer with poor outcomes and limited treatment options. PID23 Injection is an innovative in vivo CAR-T therapy that delivers a viral vector encoding three targets (CD19, BCMA, and CD70) directly into patients, enabling their own T cells to generate functional CAR-T cells against leukemia cells. This single-center, single-arm, open-label, dose-escalation study (3 dose levels: 0.8×10⁹, 2×10⁹, and 4×10⁹ TU) plans to enroll 3-18 patients with R/R AL aged 3-75 years, ECOG 0-2, and positive for at least one target. The primary objective is to evaluate safety, tolerability, and determine the recommended dose. Secondary objectives include preliminary efficacy (remission, survival), pharmacokinetics (CAR-T expansion), pharmacodynamics (cytokine changes), and exploratory viral clearance. After a single intravenous infusion, patients are hospitalized for ≥3 weeks, followed by monthly visits for 3 months, then every 3 months for up to 2 years. Enrollment is from May 2026 to May 2027, with follow-up through May 2029. The study is conducted at Zhujiang Hospital of Southern Medical University (PI: Prof. Li Yuhua).

Study Overview

• Status: Not yet recruiting
• Conditions: Relapsed or Refractory Acute Myeloid Leukemia (AML); Relapsed or Refractory Acute Lymphoblastic Leukemia; Relapsed or Refractory Acute Leukemia
• Intervention / Treatment: Biological: PID23 Injection

• Study Type: Interventional
• Enrollment (Estimated): 18
• Phase: Early Phase 1

Contacts and Locations

• Study Contact: Name: Yuhua Li, PhD; Phone Number: +86-020-61643188; Email: liyuhua2011gz@163.com

Study Locations

• China
  • Guangdong
    • Guangzhou, Guangdong, China, 510282
      • Department of Hematology, Zhujiang Hospital, Southern Medical University
      • Contact: Yuhua Li, PhD; Phone Number: +86-020-62782316; Email: liyuhua2011gz@163.com
      • Contact: Email: zhoulijanice@foxmail.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Patient or legal guardian voluntarily signs the informed consent form (ICF), demonstrating understanding of the study purpose and procedures, and willingness to participate.
2. Age 3 to 75 years, inclusive, male or female.
3. Diagnosis of relapsed or refractory acute leukemia per guideline criteria:

Relapsed: reappearance of leukemic cells in peripheral blood or bone marrow blasts ≥5% after achieving complete remission (CR); Refractory: failure to achieve CR after 2 courses of standard induction chemotherapy; relapse within 12 months after consolidation/intensification therapy; relapse after 12 months with no response to conventional chemotherapy; 2 or more relapses; extramedullary leukemia relapse or persistence; relapse after allogeneic hematopoietic stem cell transplantation.

4.Eastern Cooperative Oncology Group (ECOG) performance status 0 to 2. 5.Life expectancy ≥12 weeks. 6.Bone marrow morphology showing ≥5% primitive/immature lymphocytes (blasts). 7.Tumor cells positive for CD19, BCMA, or CD70 expression by flow cytometry. 8.Adequate major organ function, defined as:

1. Cardiac: left ventricular ejection fraction (LVEF) ≥40% by echocardiogram;
2. Renal: serum creatinine ≤2.0× upper limit of normal (ULN), or creatinine clearance ≥50 mL/min (Cockcroft-Gault formula);
3. Hepatic: ALT and AST ≤3.0×ULN (≤5.0×ULN if with liver involvement); total bilirubin ≤2.0×ULN (≤3.0×ULN for Gilbert's syndrome);
4. Pulmonary: oxygen saturation ≥92% on room air;
5. Hematologic: absolute neutrophil count (ANC) ≥1.0×10⁹/L, platelets ≥50×10⁹/L, hemoglobin ≥80 g/L (with bone marrow involvement, ANC ≥0.5×10⁹/L, platelets ≥20×10⁹/L permitted) - assessments allowed after transfusion or hematopoietic growth factor support.

9. For women of childbearing potential, negative serum pregnancy test; all participants agree to use reliable (non-rhythm) contraceptive methods from ICF signing through 1 year post-PID23 infusion.

Exclusion Criteria:

1. Prior treatment with CAR-T or other genetically modified cell therapies, unless the investigator determines that safety risks have been adequately excluded.
2. Received the following anti-tumor therapies prior to PID23 infusion: Chemotherapy or molecular targeted therapy within 14 days or 5 half-lives (whichever is longer) (excluding conditioning chemotherapy and intrathecal chemotherapy; intrathecal therapy must be stopped ≥1 week prior to PID23 infusion); Radiotherapy to non-hematopoietic sites within 7 days; Radiotherapy to hematopoietic sites within 14 days.
3. Any of the following cardiac conditions:

(1) New York Heart Association (NYHA) Class III or IV congestive heart failure; (2) Myocardial infarction or coronary artery bypass grafting (CABG) within 6 months prior to enrollment; (3) Clinically significant ventricular arrhythmia, or unexplained syncope (excluding vasovagal or dehydration-related); (3) History of severe non-ischemic cardiomyopathy. 4.Active or uncontrolled infection requiring systemic therapy within 1 week prior to screening.

5.Grade 2-4 acute graft-versus-host disease (GVHD) or moderate-to-severe chronic GVHD within 4 weeks prior to screening.

6.Cerebrovascular accident or seizure within 6 months prior to screening. 7.Deep vein or arterial thrombosis event within 6 months prior to screening. 8.Active malignancy other than acute leukemia (excluding: inactive disease with treatment completed >2 years; adequately treated cervical carcinoma in situ, basal/squamous cell skin carcinoma, localized prostate cancer post-curative surgery, ductal carcinoma in situ post-curative surgery).

9.Received (attenuated) live vaccine within 4 weeks prior to screening. 10.Any other condition that, in the investigator's judgment, makes the patient unsuitable for participation in this study.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: PID23 Injection (Dose Escalation); Participants receive a single intravenous infusion of PID23 Injection at one of three dose levels (0.8×10⁹, 2×10⁹, or 4×10⁹ TU) according to a rapid titration + standard 3+3 dose-escalation design. The starting dose is 0.8×10⁹ TU, with escalation to higher dose levels guided by safety and pharmacokinetic assessments. All subjects are hospitalized for observation for at least 3 weeks post-infusion and followed for up to 2 years.

Biological: PID23 Injection; PID23 is an in vivo CAR-T product, a lentiviral vector encoding CD19, BCMA, and CD70 chimeric antigen receptors, administered as a single intravenous infusion

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of Dose-Limiting Toxicities (DLTs)	Number of participants experiencing DLTs during the DLT observation period. DLT is defined as any treatment-emergent adverse event meeting protocol-specified severity criteria assessed per CTCAE v6.0 and ASTCT criteria for CRS/ICANS.	Up to 21 days post-PID23 infusion
Incidence and Severity of Treatment-Emergent Adverse Events	Number and percentage of participants experiencing adverse events (AEs), graded per CTCAE v6.0. Includes all AEs, serious AEs (SAEs), and AEs of special interest (CRS, ICANS, HLH/MAS). Causality assessment performed by the investigator.	Up to 2 years post-PID23 infusion

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Objective Response Rate at 3 Months	Proportion of participants achieving complete remission (CR) or CR with incomplete blood count recovery (CRi) at 3 months post-infusion. CR defined as bone marrow blasts <5%, no peripheral blasts, ANC ≥1.0×10⁹/L, platelets ≥100×10⁹/L, no extramedullary disease. CRi defined as meeting all CR criteria except platelet <100×10⁹/L and/or ANC <1.0×10⁹/L.	At 3 months post-infusion
Duration of Remission (DOR)	Time from first documented CR or CRi to first documented disease progression (PD) or death from any cause, whichever occurs first. Participants who do not achieve CR/CRi are not applicable for this analysis. Assessed per protocol until 2 years post-infusion.	Up to 2 years post-infusion
Progression-Free Survival (PFS)	Time from PID23 infusion to first documented disease progression (PD) or death from any cause, whichever occurs first. Participants alive without progression are censored at the date of last disease assessment. Assessed per protocol through 2 years post-infusion or until event.	Up to 2 years post-infusion
Overall Survival (OS)	Time from PID23 infusion to death from any cause. Participants alive at the end of follow-up are censored at the date of last known survival status. Assessed through 2 years post-infusion or until death, whichever occurs first.	Up to 2 years post-infusion
Change from Baseline in Bone Marrow Blast Percentage	Change from baseline in percentage of bone marrow blasts assessed by bone marrow morphology. Measured at screening and at protocol-specified follow-up time points (M1, M2, M3, and every 3 months thereafter). Assessed per protocol schedule.	Baseline through 2 years post-infusion
Maximum Concentration (Cmax) of CAR-T Cells in Peripheral Blood	Maximum concentration (Cmax) of CAR-T cells in peripheral blood, measured as CAR DNA copy number by quantitative PCR (copies/μg DNA) and/or percentage of CAR+ cells by flow cytometry. Blood samples collected at protocol-specified time points: 0h, 30min, 2h, 6h, 12h, D2, D4, D7, D10, D14, D21, M1, M2, M3, and long-term follow-up. Samples analyzed by the technology partner.	Day 0 through 2 years post-infusion
Time to Maximum Concentration (Tmax) of CAR-T Cells	Time to reach maximum concentration (Tmax) of CAR-T cells in peripheral blood, measured as CAR DNA copy number by quantitative PCR. Blood samples collected at protocol-specified time points from immediately post-infusion through long-term follow-up. Tmax determined from the concentration-time profile.	Day 0 through 2 years post-infusion
Area Under the Curve (AUC0-28d) of CAR-T Cells	Area under the concentration-time curve from Day 0 to Day 28 (AUC0-28d) of CAR-T cells in peripheral blood, measured as CAR DNA copy number by quantitative PCR. Calculated using the linear trapezoidal rule. Blood samples collected at protocol-specified time points through Day 28.	Day 0 through Day 28
Change from Baseline in Serum Cytokine Levels	Change from baseline in serum cytokine concentrations, including but not limited to IL-6, IL-1β, IL-2/IL-2R, IL-8, IL-10, TNF-α, IFN-γ, CRP, and ferritin. Blood samples collected at protocol-specified time points: screening, D0 (pre-infusion), D2, D4, D7, D10, D14, and M1.	Baseline through Month 1

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Viral Clearance from Body Fluids	Detection of viral vector sequences in body fluid samples including blood, saliva, urine, and stool. Viral clearance is defined as two consecutive negative results. Samples collected at protocol-specified time points: 0h, 30min, 2h, 6h, 12h, D2, D4, D7, D10, D14, D21, and M1. Samples may be stored at -80°C and shipped in batches to the technology partner for analysis. Viral clearance assessed until two consecutive negative results are obtained.	Day 0 through Month 1 or until two consecutive negatives, whichever came first

Collaborators and Investigators

• Sponsor: Zhujiang Hospital
• Collaborators: Chongqing Precision Biotech Co., Ltd

Study record dates

Study Major Dates

• Study Start (Estimated): August 1, 2026
• Primary Completion (Estimated): May 30, 2029
• Study Completion (Estimated): March 31, 2030

Study Registration Dates

• First Submitted: July 6, 2026
• First Submitted That Met QC Criteria: July 9, 2026
• First Posted (Actual): July 10, 2026

Study Record Updates

• Last Update Posted (Actual): July 10, 2026
• Last Update Submitted That Met QC Criteria: July 9, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Acute Myeloid Leukemia; Relapsed; Refractory; AML; Acute Leukemia; B-ALL; Acute lymphoblastic leukemia; In vivo CAR-T; PID23
• Additional Relevant MeSH Terms: Pathologic Processes; Neoplasms; Disease Attributes; Immune System Diseases; Neoplasms by Histologic Type; Hematologic Diseases; Lymphatic Diseases; Lymphoproliferative Disorders; Immunoproliferative Disorders; Leukemia, Myeloid; Leukemia, Lymphoid; Leukemia; Pathological Conditions, Signs and Symptoms; Hemic and Lymphatic Diseases; Recurrence; Leukemia, Myeloid, Acute; Precursor Cell Lymphoblastic Leukemia-Lymphoma
• Other Study ID Numbers: 2026-KY-163-01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: IPD will not be shared due to: (1) ongoing study with long-term follow-up through 2 years post-infusion; (2) small sample size (3-18) with high participant re-identification risk; (3) sensitive genetic information (CAR-T viral vector integration data) contained in the IPD; and (4) lack of infrastructure and funding for IPD sharing at this single-center investigator-initiated study. Comprehensive study findings will be published in peer-reviewed journals. Requests for access to raw IPD for legitimate research purposes may be directed to the corresponding author via email.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No