186O Patient-reported outcomes (PROs) from DESTINY-Breast02, a randomized phase III study of trastuzumab deruxtecan (T-DXd) vs treatment of physician’s choice (TPC) in patients (pts) with HER2–positive (HER2+) metastatic breast cancer (mBC)

In DESTINY-Breast02 (NCT03523585), T-DXd improved progression-free and overall survival vs TPC in pts with HER2+ mBC who were resistant/refractory to trastuzumab emtansine (T-DM1) (Krop et al. SABCS 2022). Here, we report data on PROs health-related quality of life (QoL). Pts (immunohistochemistry [IHC] 3+ or IHC 2+/in situ hybridization amplified) T-DM1–resistant/refractory assigned 2:1 (trastuzumab + capecitabine lapatinib capecitabine). collected measured at prespecified timepoints using the European Organization for Research Treatment Cancer QoL questionnaires (EORTC QLQ)-C30, breast-cancer–specific EORTC QLQ-BR45 (scored as QLQ-BR23), EuroQol 5-dimension 5-level (EQ-5D-5L) visual analog scale. Change from baseline (CFB) time definitive deterioration (TDD) assessed. QLQ-C30 global health status (GHS)/QoL score was primary variable interest. (n = 406) 202) arms (median treatment duration safety analysis set: 11.3 ∼4.5 mo), questionnaire compliance >92% >76% cycles 3-29. Mean CFB GHS/QoL remained stable (within ±10 points) up cycle 39 21 TPC, after which number not informative < 10%). Median TDD longer (14.1 5.9 mo; HR, 0.56 [95% CI, 0.44-0.71]) all subscales, including physical functioning (18.7 6.8 0.46 0.36-0.60]) pain 5.8 0.38 0.29-0.49]), exception nausea/vomiting (5.7 6.1 1.09 0.86-1.39]). With experienced prolonged QLQ-BR23 arm symptom subscale (18.3 8.8 0.57 0.44-0.75]). suggested that maintained T-DXd-treated pts. except nausea/vomiting, receiving TPC. These results continue support benefit T-DM1–resistant mBC.