Primary Objectives:~To characterize the safety and tolerability of CB-103 in combination with Venetoclax in adolescent (12 to 18 years), and young adult (19 to 40 years) patients with relapsed/refractory T-cell acute lymphoblastic leukemia (T-ALL) and T-cell lymphoblastic lymphoma (T-LBL).~To assess the efficacy of CB-103 in combination with venetoclax by the overall response rate (ORR), defined as complete remission (CR), plus CR with incomplete blood count recovery (CRi) [1] plus partial remission (PR) [2], in adolescent, and young adult patients with relapsed/refractory T-ALL/T-LBL.~Secondary Objectives:~To assess whether the ORR to CB-103 in combination with Venetoclax is dependent on pre-treatment expression of Notch and/or BCL2 pathway.~To determine the preliminary assessment of CB-103 in combination with Venetoclax by other efficacy parameters such as minimal residual disease (MRD), duration of response (DoR), overall survival (OS) and event-free survival (EFS) in adolescent and young adult patients with relapsed/refractory T-ALL/T-LBL.~Exploratory Objectives:~To explore potential correlations of ORR to treatment and additional pharmacodynamic (PD) markers, i.e., other oncogenic pathway activations that may co-occur at the start of treatment.~To evaluate how many patients are able to transition to Hematopoietic Stem Cell~Transplant (HSCT):~Either in the patients achieving CR after the induction and reinduction cycles;~Or in the patients with PR or stable disease (SD) after the induction and reinduction.
To learn if the combination of 2 study drugs, CB-103 and venetoclax, can help to control T-cell acute lymphoblastic leukemia (T-ALL) or T-cell lymphoblastic leukemia (T-LBL) in adolescent and young adult patients