Q-TWiST Analysis of Sacituzumab Govitecan vs. Chemotherapy in Previously Treated Patients with HR+/HER2− Metastatic Breast Cancer

In TROPiCS-02, sacituzumab govitecan (SG) demonstrated significantly longer overall survival and progression-free survival with improved quality of life vs. chemotherapy treatment of physician's choice (TPC) in patients with HR+/HER2- metastatic breast cancer (mBC). The safety profile was consistent with previous studies of SG. We assessed the benefit--risk profile of SG vs. TPC by integrating patient preferences with clinical benefits using Quality-adjusted Time Without Symptoms of disease progression or Toxicity of treatment (Q-TWiST) analysis in this study population. Survival time was partitioned into three health states: TOX (grade ≥3 treatment-emergent adverse events [TEAEs] after randomization/before disease progression), REL (disease progression until death or end of follow-up), and TWiST (time without progression or grade ≥3 TEAEs). Health state utility weights were obtained from the published literature. The established threshold for clinically important Q-TWiST gain is 10%. SG demonstrated significantly improved Q-TWiST vs. TPC (mean 9.7 vs. 8.1 months; difference 1.6 months; 95% CI, 0.5-2.7; <i>p</i> = 0.0067), which increased with longer follow-up. Relative Q-TWiST improvement met the threshold for clinical importance at 10.8%. Time in TOX was numerically higher with SG than TPC, and the difference stabilized over time. Q-TWiST supports a positive benefit-risk profile for SG over TPC in patients with pretreated HR+/HER2- mBC.