A Phase III Randomised Study to Evaluate Dato-DXd and Durvalumab for Neoadjuvant/Adjuvant Treatment of Triple-Negative or Hormone Receptor-low/HER2-negative Breast Cancer

Inclusion Criteria

• Participant must be ≥ 18 years, at the time of signing the ICF.
• Histologically confirmed Stage II or III unilateral or bilateral primary invasive TNBC or hormone receptor-low/HER2-negative breast cancer
• ECOG PS of 0 or 1
• Provision of acceptable tumor sample
• Adequate bone marrow reserve and organ function
• Contraceptive use by males or females should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies and aligned with protocol requirements.

Exclusion Criteria

• History of any prior invasive breast malignancy
• History of another primary malignancy except for malignancy treated with curative intent with no known active disease within 5 years before randomization.
• active or prior documented autoimmune or inflammatory disorders.
• Evidence of distant disease.
• Clinically significant corneal disease.
• Has active or uncontrolled hepatitis B or C virus infection.
• Known HIV infection that is not well controlled.
• Uncontrolled infection requiring i.v. antibiotics, antivirals or antifungals; suspected infections; or inability to rule out infections.
• Known to have active tuberculosis infection
• Mean resting corrected QTcF interval > 470 ms obtained from ECG
• Uncontrolled or significant cardiac disease.
• History of non-infectious ILD/pneumonitis
• Has severe pulmonary function compromise
• Any prior or concurrent surgery, radiotherapy or systemic anticancer therapy for TNBC or hormone receptor-low/HER2-negative breast cancer
• For females only: is pregnant (confirmed with positive serum pregnancy test) or breastfeeding, or planning to become pregnant.
• Female participants should refrain from breastfeeding from enrolment throughout the study and for at least 7 months after last dose of study intervention, or as dictated by local PI for SoC if longer.
• Concurrent use of systemic hormone replacement therapy or oral hormonal contraception