This is a Phase 1/2, global multicentre, open-label, single-arm, dose escalation and dose optimisation study of AZD0486 to evaluate the safety, tolerability, and efficacy of AZD0486 monotherapy in participants with R/R B ALL who have received ≥ 2 prior lines of therapies. The study will consist of 3 parts. Part A monotherapy dose escalation. Part B dose optimisation. Part C Dose expansion at the recommended phase 2 dose (RP2D)

This dose escalation and optimization study is evaluating the safety, tolerability, PK, PD and clinical activity of AZD0486 monotherapy in r/r B-ALL.

Inclusion Criteria:

• Age: 12 years and above (Parts A, B and C).

• Participants with B-cell Acute Lymphoblastic Leukemia with CD19 expression by local lab with:

  1. Bone marrow infiltration with >/= 5% blasts
  2. Either relapsed or refractory after a minimum of 2 prior therapies or after 1 prior line of therapy if no SOC available option.
  3. Philadelphia positive participants are allowed in all parts of the study, if intolerant or refractory to TKIs.

• For participants older than 16 years, Eastern Cooperative Oncology Group (ECOG) Performance Status less than or equal to 2. For Participants 16 years or younger, Lansky score more or equal to 50%.

The above is a summary, other inclusion criteria details may apply.

Exclusion Criteria:

• Active CNS involvement by B-ALL, defined by presence of ALL blasts in CSF (CNS2 and CNS3 criteria).
• Isolated extramedullary disease relapse.
• Testicular leukemia
• History or presence of clinically relevant CNS pathology such as epilepsy, seizure, paresis, aphasia, stroke, severe brain injuries, dementia, Parkinson's disease, cerebellar disease, organic brain syndrome, or psychosis; or prior Grade 4 neurotoxicity with CAR-T or TCE therapy.
• History of other malignancy (with certain exceptions).
• Unresolved AEs >/= Grade 2, from prior therapies
• Prior therapy with TCEs within 4 weeks, CAR T-cell therapy or autologous HSCT within 8 weeks or prior alloSCT within 12 weeks of start of therapy.
• GVHD requiring immunosuppressive therapy within 3 weeks prior to AZD0486 treatment.

The above is a summary, other exclusion criteria details may apply.

Qualified researchers can request access to anonymized individual patient-level data from AstraZeneca group of companies sponsored clinical trials via the request portal. All request will be evaluated as per the AZ disclosure commitment: https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure

AstraZeneca will meet or exceed data availability as per the commitments made to the EFPIA Pharma Data Sharing Principles. For details of our timelines, please rerefer to our disclosure commitment at https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure

When a request has been approved AstraZeneca will provide access to the de-identified individual patient-level data in an approved sponsored tool . Signed Data Sharing Agreement (non-negotiable contract for data accessors) must be in place before accessing requested information. Additionally, all users will need to accept the terms and conditions of the SAS MSE to gain access. For additional details, please review the Disclosure Statements at https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure