PFS is defined as the time from randomization until radiological progression per Response Evaluation Criteria in Solid Tumors, Version 1.1 (RECIST 1.1) as assessed by Blinded Independent Central Review (BICR), or death due to any cause.

OS is defined as the time from randomization until the date of death due to any cause.

The analysis will include all randomised participants as randomised. All events will be included, regardless of whether the participant withdraws from randomised therapy or receives another anti-cancer therapy. The measure of interest is the HR of DFS. Descriptive analyses of Dato-DXd in combination with rilvegostomig versus rilvegostomig monotherapy and rilvegostomig monotherapy versus SoC will be performed to assess contribution of components.

PFS is defined as time from randomisation until progression per RECIST 1.1 as assessed by BICR, or death due to any cause. The analysis will include all randomised participants, as randomised, regardless of whether the participant withdraws from randomised therapy, receives another anti-cancer therapy or clinically progresses prior to RECIST 1.1 progression, in the following population: • TROP2 biomarker positive population The measure of interest is the HR of PFS. PFS by investigator will be reported as a sensitivity analysis.

OS is defined as the time from randomisation until the date of death due to any cause. The analysis will include all randomised participants, as randomised, regardless of whether the participant withdraws from randomised therapy or receives another anti-cancer therapy, in the following population: • TROP2 biomarker positive population The measure of interest is the HR of OS.

PFS is defined as time from randomisation until progression per Response Evaluation Criteria in Solid Tumors, Version 1.1 (RECIST 1.1) as assessed by BICR, or death due to any cause.

OS is defined as the time from randomisation until the date of death due to any cause.

PFS is defined as time from randomisation until progression per RECIST 1.1 as assessed by BICR, or death due to any cause.

OS is defined as the time from randomisation until the date of death due to any cause.

Progression-free Survival (PFS) is defined as the time from randomization to the first documented radiographic disease progression or death due to any cause, whichever occurs first, assessed by blinded independent central review (BICR) per Response Evaluation Criteria in Solid Tumors (RECIST), Version 1.1.

Overall Survival (OS) is defined as the time from randomization to death due to any cause.

Proportion of participants who have a confirmed CR or confirmed PR, as determined by the investigator at local site per RECIST 1.1.

Number of patients with adverse events and with serious adverse events including abnormal clinical observations, abnormal Electrocardiogram (ECG) parameters, abnormal laboratory assessments and abnormal vital signs that changed from baseline.

Proportion of participants achieving a ≥ 50% decrease in PSA from baseline to the lowest post-baseline PSA result, confirmed by a second consecutive PSA assessment at least 3 weeks later.

PFS is defined as time from start of treatment until progression per RECIST 1.1 as assessed by the investigator or death due to any cause.

Confirmed ORR is defined as the proportion of participants in each cohort who have a confirmed CR or confirmed PR, as assessed by ICR per RECIST 1.1.

DLTs, TEAEs, SAEs, AESIs, ECOG PS, vital sign measurements, standard clinical laboratory parameters (hematology, clinical chemistry, and urinalysis), ECG parameters, ECHO/MUGA scan findings, and ophthalmologic findings