CD19 Sequential CD22 In Vivo CAR-T Cell Immunotherapy for Relapsed/Refractory B-Cell Acute Lymphoblastic Leukemia

Trial details

Who runs it

Liping Dou

Trial code

NCT07927816

Record updated

10 November 2026

Original description

This is a single-center, open-label, single-arm, prospective, investigator-initiated dose-escalation study to evaluate the safety, tolerability, preliminary efficacy, and cellular kinetics of an in vivo CAR-T cell immunotherapy targeting CD19 sequentially followed by CD22, in patients with relapsed or refractory B-cell acute lymphoblastic leukemia (R/R B-ALL). The investigational product is a targeted lentiviral vector that transduces the patient's endogenous T/NK cells in situ; no leukapheresis, ex vivo manufacturing, or lymphodepleting conditioning is required. Participants receive an intravenous infusion of CD19-targeted in vivo CAR-T on Day 0, followed by an intravenous infusion of CD22-targeted in vivo CAR-T on Day 7. Before the Day 7 infusion, the investigator will assess each participant to determine whether the second infusion should proceed, based on: (i) the proportion of CAR-positive T/NK cells in peripheral blood, which reflects the success of in vivo transduction and early expansion after the first infusion; (ii) the maximum grade and current control of adverse events occurring after the first infusion, including cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS); and (iii) the participant's general condition, including Eastern Cooperative Oncology Group (ECOG) performance status and vital organ function (cardiac, hepatic, renal, pulmonary, and coagulation). The second infusion will be postponed or cancelled if any of these assessments indicates that the risk outweighs the benefit, for example grade >=3 CRS or grade >=2 ICANS that has not resolved to grade <=1, or investigator-judged deterioration in organ function. Dose escalation follows a traditional 3+3 design with planned dose levels of 1×10\^9, 3×10\^9, and 6×10\^9 transducing units (TU), guided by dose-limiting toxicities (DLTs) assessed during Days 0-28; higher dose levels may be explored if the maximum tolerated dose is not reached. Treatment-emergent adverse events and serious adverse events, including CRS, immune effector cell-associated neurotoxicity syndrome (ICANS), hematologic toxicity, and organ toxicity, will be assessed. Preliminary antitumor activity will be evaluated by objective response rate (ORR), overall survival (OS), and progression-free survival (PFS), and the expansion and persistence of in vivo-generated CAR-T cells in peripheral blood will also be evaluated.Read full original descriptionShow less

A Single-Arm, Dose-Escalation Clinical Study on the Safety of CD19 Sequential CD22 In Vivo CAR-T Cell Immunotherapy for Relapsed/Refractory B-Cell Acute Lymphoblastic Leukemia

This is a single-center, open-label, single-arm, prospective, investigator-initiated dose-escalation study to evaluate the safety, tolerability, preliminary efficacy, and cellular kinetics of an in vivo CAR-T cell immunotherapy targeting CD19 sequentially followed by CD22, in patients with relapsed or refractory B-cell acute lymphoblastic leukemia (R/R B-ALL). The investigational product is a targeted lentiviral vector that transduces the patient's endogenous T/NK cells in situ; no leukapheresis, ex vivo manufacturing, or lymphodepleting conditioning is required. Participants receive an intravenous infusion of CD19-targeted in vivo CAR-T on Day 0, followed by an intravenous infusion of CD22-targeted in vivo CAR-T on Day 7. Before the Day 7 infusion, the investigator will assess each participant to determine whether the second infusion should proceed, based on: (i) the proportion of CAR-positive T/NK cells in peripheral blood, which reflects the success of in vivo transduction and early expansion after the first infusion; (ii) the maximum grade and current control of adverse events occurring after the first infusion, including cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS); and (iii) the participant's general condition, including Eastern Cooperative Oncology Group (ECOG) performance status and vital organ function (cardiac, hepatic, renal, pulmonary, and coagulation). The second infusion will be postponed or cancelled if any of these assessments indicates that the risk outweighs the benefit, for example grade >=3 CRS or grade >=2 ICANS that has not resolved to grade <=1, or investigator-judged deterioration in organ function. Dose escalation follows a traditional 3+3 design with planned dose levels of 1×10\^9, 3×10\^9, and 6×10\^9 transducing units (TU), guided by dose-limiting toxicities (DLTs) assessed during Days 0-28; higher dose levels may be explored if the maximum tolerated dose is not reached. Treatment-emergent adverse events and serious adverse events, including CRS, immune effector cell-associated neurotoxicity syndrome (ICANS), hematologic toxicity, and organ toxicity, will be assessed. Preliminary antitumor activity will be evaluated by objective response rate (ORR), overall survival (OS), and progression-free survival (PFS), and the expansion and persistence of in vivo-generated CAR-T cells in peripheral blood will also be evaluated.

Inclusion: Voluntarily agrees to participate in the study, has signed the informed consent form, and is willing and able to comply with scheduled visits, study treatment, laboratory tests, and other study procedures; Diagnosis of relapsed/refractory B-cell acute lymphoblastic leukemia (B-ALL) according to the World Health Organization (WHO) classification, confirmed by bone marrow aspirate morphology, flow cytometry, or histopathology, with tumor cells shown by immunophenotyping or flow cytometry to express CD19 and CD22. Relapsed/refractory B-ALL is defined as meeting at least one of the following four criteria:; Relapse within 6 months after first remission; Primary refractory disease: failure to achieve complete remission after 2 cycles of standard chemotherapy; Failure to achieve complete remission or relapse after one or more lines of salvage chemotherapy; Relapse after hematopoietic stem cell transplantation; Male or female participants aged 14 to 75 years, inclusive; Eastern Cooperative Oncology Group (ECOG) performance status of 0-2; Estimated life expectancy of more than 3 months from the date of signing the informed consent form; Adequate renal, hepatic, cardiac, and pulmonary function, defined as follows:; Creatinine clearance (estimated by the Cockcroft-Gault formula) ≥60 mL/min or serum creatinine ≤1.5 × the upper limit of normal (ULN); Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST)≤2.5×upper limit of normal (ULN), total bilirubin≤1.5×ULN; Cardiac ejection fraction≥50%, no pericardial effusion on echocardiography, and no significant abnormalities on electrocardiogram (ECG); No clinically significant pleural effusion, and oxygen saturation >92% on room air at baseline; Participants of reproductive potential must agree to use highly effective contraception before enrollment and for at least 12 months after SL1CC infusion. A negative serum pregnancy test is required for women of childbearing potential at screening. Participants must immediately notify the investigator if pregnancy occurs or is suspected.

Exclusion: Concurrent progressive malignancy other than acute lymphoblastic leukemia; Human immunodeficiency virus (HIV) infection, known acquired immunodeficiency syndrome (AIDS), or syphilis infection; has received a live vaccine within 4 weeks, or is anticipated to require a live vaccine during the study period; Prior treatment with any gene therapy product or any in vivo CAR-T therapy, or known pre-existing neutralizing immunity to the lentiviral vector; Active central nervous system (CNS) leukemia or leptomeningeal involvement not controlled after adequate intrathecal therapy; cerebrospinal fluid examination is required during screening; The patient has severe autoimmune disease, congenital immunodeficiency or active autoimmune disease requiring ongoing systemic immunosuppressive treatment, or is currently within the washout period after having received medications that may affect CAR-T cell immunotherapy, or is anticipated to require medications during the study period that may affect CAR-T cell immunotherapy treatment, or active GVHD requiring systemic therapy; A history of severe pulmonary disease associated with impaired lung function; Severe active infection that cannot be effectively controlled, defined as sepsis or an infection with an uncontrolled infectious focus. Participants may be enrolled after the infection has been adequately controlled; Severe autoimmune disease or congenital immunodeficiency; Active hepatitis B or hepatitis C infection, defined as hepatitis B virus DNA (HBV DNA) or hepatitis C virus RNA (HCV RNA) levels above the lower limit of detection; History of severe immediate hypersensitivity reactions to any drug required in this study, including antibiotics, or to biological products; The patient has severe cardiac dysfunction, or left ventricular ejection fraction (LVEF) <50%, or a history within the 12 months prior to enrollment of myocardial infarction, coronary angioplasty or coronary stent implantation, unstable angina, clinically significant arrhythmia, or other severe cardiovascular diseases; Any other severe physical or psychiatric disorder or clinically significant laboratory abnormality that may increase the risk associated with study participation, interfere with the interpretation of study results, or, in the investigator's judgment, make the participant unsuitable for participation in the study; Pregnancy or breastfeeding (lactation); The investigator judges that the patient is unlikely to complete all visits and procedures required by the study protocol (including medium- and long-term follow-up visits), such as insufficient willingness of the patient and their family members to participate in the study, refusal to participate, inability of the patient to fully cooperate with the study arrangements, or inadequate compliance on the part of the patient and their family members.

ClinicalTrials.gov NCT07927816