Treatment patterns, adverse events, and direct and indirect economic burden in a privately insured population of patients with HR+/HER2- metastatic breast cancer in the United States.

The increasing use of chemotherapy as patients progressed to second and later lines and the substantial direct/indirect economic burden underscore an unmet need. The high number of 1L regimens highlights significant heterogeneity and a lack of consensus related to the management of HR+/HER2- MBC in routine practice.