Outcomes of subsequent treatment regimens after trastuzumab deruxtecan in patients with metastatic breast cancer
Menée à partir de données 2019-2023 portant sur 793 patientes atteintes d'un cancer du sein de stade métastatique, cette étude évalue l'efficacité, du point de vue de la survie sans progression dans un contexte de vie réelle et de la survie globale, du trastuzumab déruxtécan en fonction du sous-type de la maladie (surexpression ou non de HR/HER2, cancer triple négatif)
Background: Most patients with metastatic breast cancer (MBC) are eligible for treatment with trastuzumab deruxtecan (T-DXd). No data are available to guide treatment after exposure to T-DXd.
Methods: We utilized a nationwide electronic health record-derived, deidentified database to review data of patients with MBC who initiated T-DXd between 12/2019 and 9/2023 and who received an additional line of treatment after T-DXd. Tumors were categorized as HER2-positive if ever positive before T-DXd, HER2-negative if never HER2-positive before T-DXd. We compared real-world progression-free survival (rwPFS) and overall survival for post-T-DXd treatments using the Kaplan-Meier method and the log-rank test.
Results: We identified 793 patients receiving a post-T-DXd treatment. Post-T-DXd treatment outcomes differed significantly by MBC subtype: median rwPFS was 4.6 months for HER2-positive, 3.4 months for hormone receptor- (HR)-positive/HER2-negative and 2.8 months for triple-negative MBC (p < .001). Outcomes with post-T-DXd treatments also varied significantly according to treatment regimen (p < .001). Among patients with HER2-positive MBC, median rwPFS ranged from 6.7 months with endocrine treatment regimens to 2.3 months with sacituzumab govitecan (SG). Among patients with HR-positive/HER2-negative MBC, rwPFS ranged from 5.9 months with eribulin to 2.5 months with SG. Among patients with triple-negative MBC, poor outcomes (rwPFS ≤3 months) were observed with most treatment regimens, including SG (3 months), eribulin (2 months) and multiagent chemotherapy (2.5 months).
Conclusions: Outcomes of post-T-DXd treatments differ significantly by MBC subtype and type of regimen administered. The use of SG immediately after T-DXd was associated with relatively short rwPFS across subtypes, highlighting some degree of cross-resistance with T-DXd.
Journal of the National Cancer Institute , résumé, 2025