Efficacy and safety of ixabepilone plus capecitabine in elderly patients with anthracycline- and taxane-pretreated metastatic breast cancer.

Abstract

1083 Background: Data on chemotherapy for elderly patients (pts) with metastatic breast cancer (MBC) are limited. We performed a retrospective analysis of elderly pts (≥65 years of age) enrolled into the pivotal phase III studies of ixabepilone plus capecitabine versus capecitabine alone in order to determine the efficacy and safety of these agents compared with the overall population. Methods: 1,973 pts with MBC previously treated with or resistant to anthracyclines and taxanes were randomized in two open-label, multinational, phase III studies to receive either ixabepilone (40 mg/m2 IV over 3h q3w) plus capecitabine (1,000 mg/m2 PO BID x 14d q3w) or capecitabine alone (1,250 mg/m2 PO BID x 14d q3w). Due to the similarity of the study populations, individual patient data from both studies were pooled. 251 randomized pts were ≥65 years of age. Results: Efficacy endpoints in the elderly population were consistent with pts <65 years of age. The combination of ixabepilone plus capecitabine was favored over capecitabine monotherapy (Table). Grade 3 or 4 hematologic adverse events (AEs) occurring in >5% of pts receiving ixabepilone plus capecitabine were similar in pts <65 and ≥65 years of age: neutropenia 21% vs 26% and febrile neutropenia 5% vs 10%. Non-hematologic AEs occurring in >5% of pts receiving ixabepilone plus capecitabine were also similar in these age groups and included: fatigue 10% vs 12%, asthenia 6% vs 14%, peripheral sensory neuropathy 14% vs 17%, and hand-foot syndrome 20% vs 19%. Conclusions: The combination of ixabepilone plus capecitabine maintains its efficacy in elderly pts with anthracycline and taxane pretreated MBC. Furthermore, the safety profile of ixabepilone plus capecitabine is similar in pts <65 and ≥65 years of age. <65 years of age ≥65 years of age Ixa + cape cape Ixa + cape cape n 751 740 104 116 ORR,* n (%) 317 (42) 194 (26) 38 (37) 22 (19) Median PFS, mo 5.6 4.2 5.5 3.9 HR (95% CI) 0.81 (0.73–0.90) 0.77 (0.59–1.02) n 868 853 116 135 Median OS, mo 14.7 13.9 13.9 12.2 HR (95% CI) 0.90 (0.81–1.01) 1.07 (0.81–1.40) * ORR and PFS were computed on all randomized pts with measurable disease strata.