{"analyses":[{"ciLowerLimit":"0.52","ciNumSides":"TWO_SIDED","ciPctValue":"95","ciUpperLimit":"0.75","estimateComment":"HR and CI were calculated using a stratified Cox proportional hazards model, adjusting for prior cyclin-dependent kinase (CDK)4/6 inhibitor use (yes versus no) and HER2 IHC expression (IHC 1+ versus IHC 2+/ISH-) and ties handled by Efron approach.","groupIds":["OG000","OG001"],"nonInferiorityType":"SUPERIORITY","pValue":"<0.0001","paramType":"Hazard Ratio (HR)","paramValue":"0.62","statisticalComment":"The analysis was performed using the stratified log-rank test.","statisticalMethod":"Log Rank"}],"classes":[{"categories":[{"measurements":[{"groupId":"OG000","lowerLimit":"11.4","upperLimit":"15.2","value":"13.2"},{"groupId":"OG001","lowerLimit":"7.0","upperLimit":"9.0","value":"8.1"}]}]}],"denoms":[{"counts":[{"groupId":"OG000","value":"359"},{"groupId":"OG001","value":"354"}],"units":"Participants"}],"description":"PFS per Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1) assessed by BICR was defined as the time from the date of randomization until the date of PD, as defined or death (by any cause in the absence of progression) regardless of whether the participant withdrew from randomized therapy or received another anticancer therapy prior to progression. PD was defined as at least a 20% increase in the sum of diameters of target lesions (TLs), taking as reference the smallest previous sum of diameters (nadir), this included the baseline sum if that was the smallest on study. In addition to the relative increase of 20%, the sum must demonstrate an absolute increase of at least 5 millimeter (mm) from nadir. Median PFS was calculated using Kaplan-Meier method and its confidence interval (CI) using Brookmeyer-Crowley method.","dispersionType":"95% Confidence Interval","groups":[{"description":"Participants received T-DXd 5.4 mg/kg via IV infusion every 3 weeks until PD, unacceptable toxicity, withdrawal of consent, or another criterion for discontinuation was met.","id":"OG000","title":"T-DXd"},{"description":"Participants received Investigator's choice single-agent chemotherapy (capecitabine 1000 or 1250 mg/m\\^2 orally twice daily for 2 weeks followed by a 1-week rest period in 3-week cycles, paclitaxel 80 mg/m\\^2 via IV infusion qw in 3-week cycles or nab-paclitaxel 100 mg/m\\^2 via IV infusion qw for 3 weeks followed by 1-week rest period in 4-week cycles) until PD, unacceptable toxicity, withdrawal of consent, or another criterion for discontinuation was met.","id":"OG001","title":"Chemotherapy"}],"paramType":"MEDIAN","populationDescription":"The HER2-low population included the subset of participants in the ITT population with HER2 immunohistochemistry (IHC) 2+/ in situ hybridization (ISH)- and IHC 1+ as determined per the interactive response technology (IRT) data for HER2 IHC expression.","reportingStatus":"POSTED","timeFrame":"Response evaluations performed at screening, every 6 weeks (q6w) ± 1 week from randomization for 48 weeks, and then every 9 weeks (q9w) ± 1 week, starting at Week 48 until PD, up to PCD of 18 March 2024 (maximum of approximately 43.85 months)","title":"Progression-Free Survival (PFS) Assessed by Blinded Independent Central Review (BICR) in the Hormone Receptor-Positive (HR+), Human Epidermal Growth Factor Receptor 2 (HER2)-Low Population","type":"PRIMARY","unitOfMeasure":"months"}