This analysis examined demographics, clinical characteristics, and real-world (RW) outcomes for patients (pts) prescribed eribulin (ERI) early vs late for the treatment of TN MBC.
Physicians from the Cardinal Health Oncology Research Network completed electronic case-report forms on adult females with TN MBC and pathologically confirmed metastatic disease who received ERI between 01/01/11 and 01/01/14. Providers indicated treatments by line of therapy (LOT) up to ERI treatment. Data included clinical parameters, treatment events, outcomes, dosing, adverse events, supportive-care medications, and hospitalizations. By design, one-half the sample were early ERI users (LOT 1/2) and one-half were late ERI users (LOT 3+). Kaplan-Meier methods were used to calculate median overall survival (OS).
252 pts with TN MBC were identified by 43 providers; 125 (49.6%) were early ERI users and 127 (50.4%) were late ERI users. Overall, 45.4% were stage IV at diagnosis. Mean age at ERI treatment: 57 years, early ERI users; 54 years, late ERI users. Mean length of follow-up: 27 months (mos) from initiation of first-line metastatic treatment, with 76.2% of pts deceased by the end of follow-up. Mean duration of treatment: 5.6 mos (standard deviation=4.3). Early users were more likely (P=0.05) to have a complete/partial response (CR/PR; 71.1% vs 47.7%) and less likely to have progressive disease (PD; 7.1% vs 12.3%). Median OS was 23.0 mos (95% CI: 18.7–22.4) for early ERI users and 14.7 mos (95% CI: 12.6–16.9) for late ERI users.
RW outcomes of ERI therapy demonstrated response rates in >2/3 of early- and ~1/2 of late-treated pts (not verified by external investigator), considerably higher than in the EMBRACE randomized controlled trial (12%). The estimated RW OS of 14.7 mos for late ERI users is consistent and slightly longer than the 13.1 mos observed in the EMBRACE trial.