5699 - Patterns and predictors of first-line (1L) taxane use in US patients with metastatic triple-negative breast cancer (mTNBC)

Background

TNBC accounts for approximately 15% to 20% of breast cancers. Patients with TNBC tend to have a worse prognosis and are typically diagnosed at a younger age compared with patients with other breast cancer subtypes. Chemotherapy has been the foundation of care for patients with mTNBC, but new targeted treatment (tx) options are now available (olaparib, veliparib, atezolizumab). The IMpassion130 study showed that the combination of atezolizumab + nab-paclitaxel (pac) improved efficacy outcomes in 1L mTNBC. This analysis was conducted to assess the characteristics of patients receiving taxanes in current US clinical practice.

Methods

A total of 2250 female patients newly diagnosed with mTNBC and who received 1L tx between 2005 and 2015 were identified in the Truven MarketScan database. Descriptive statistics were used to summarize baseline characteristics. Multivariate logistic regression models were used to identify independent predictors of treatment choice. Models included all prognostic variables.

Results

The median age of patients at 1L tx for mTNBC was 58 years. Most patients lived in metropolitan areas (86%) and were covered by commercial health insurance (74%). Taxane-containing regimens accounted for 54% of all 1L tx, with 23% receiving monotherapy and 26% receiving combination. nab-Pac was most commonly given as a single agent (64%), whereas pac and docetaxel were more commonly given in combination with other agents (62% and 67%, respectively). Single-agent vs combination taxane use, as well as the use of nab-pac regimens (vs docetaxel or pac) increased after 2010 compared with prior to 2010. Patients enrolled in a health maintenance organization plan were less likely to receive nab-pac than pac (odds ratio [OR], 0.41 [0.21-0.79]) or docetaxel (OR, 0.25 [0.12-0.51]). Other factors, such as comorbidities and number of metastatic sites, were not clearly associated with any specific taxane monotherapy tx.

Conclusions

Taxanes were the most common tx choice for 1L mTNBC. Patient characteristics were similar among patients who received pac and nab-pac monotherapy, suggesting that they are prescribed interchangeably when reimbursed by insurance.

Clinical trial identification

Editorial acknowledgement

Medical writing assistance for this abstract was provided by Chris Lum, PhD, of Health Interactions, and funded by F. Hoffmann-La Roche, Ltd.

Legal entity responsible for the study

F. Hoffmann-La Roche, Ltd.

Funding

F. Hoffmann-La Roche, Ltd.

Disclosure

J. O’Shaughnessy: Honoraria (self): AbbVie Inc.; Honoraria (self): Agendia; Honoraria (self): Amgen Biotechnology; Honoraria (self): AstraZeneca; Honoraria (self): Bristol-Myers Squibb; Honoraria (self): Celgene; Honoraria (self): Eisai; Honoraria (self): Genentech; Honoraria (self): Genomic Health; Honoraria (self): GRAIL; Honoraria (self): Immunomedics; Honoraria (self): Heron Therapeautics; Honoraria (self): Ipsen Biopharmaceuticals; Honoraria (self): Jounce Therapeutics; Honoraria (self): Lilly; Honoraria (self): Merck; Honoraria (self): Myriad; Honoraria (self): Novartis; Honoraria (self): Ondonate Therapeutics; Honoraria (self): Pfizer; Honoraria (self): Puma Biotechnology; Honoraria (self): Seattle Genetics; Honoraria (self): Syndax Pharmaceuticals. L.A. Emens: Officer / Board of Directors: Society for Immunotherapy of Cancer (SITC); Honoraria (self): Abbvie; Honoraria (self): Amgen; Honoraria (self), Research grant / Funding (institution), Travel / Accommodation / Expenses: AstraZeneca; Honoraria (self), Travel / Accommodation / Expenses: Bayer; Honoraria (self): Celgene; Research grant / Funding (institution), Travel / Accommodation / Expenses: Genentech/Roche; Honoraria (self): Gritstone; Honoraria (self): Medimmune; Honoraria (institution), Travel / Accommodation / Expenses: Macrogenics; Non-remunerated activity/ies, No Compensation: eTHeRNA; Travel / Accommodation / Expenses: Novartis; Honoraria (self): Peregrine; Honoraria (self), Travel / Accommodation / Expenses: Replimune; Honoraria (self): Syndax; Honoraria (self): Vaccinex; Research grant / Funding (institution): Aduro Biotech; Research grant / Funding (institution): Breast Cancer Research Foundation; Research grant / Funding (institution): Corvus; Research grant / Funding (institution): Department of Defense; Research grant / Funding (institution): EMD Serono; Research grant / Funding (institution): HeritX, Inc.; Research grant / Funding (institution): Maxcyte; Honoraria (self), Travel / Accommodation / Expenses: Bristol Meyers Squibb; Research grant / Funding (institution): Merck; Licensing / Royalties, IND Licensing/vaccine <25K: Aduro. S. Chui: Shareholder / Stockholder / Stock options, Full / Part-time employment: Roche/Genentech. K. Russell: Full / Part-time employment: F. Hoffmann-La Roche, Ltd. S. Lin: Shareholder / Stockholder / Stock options, Full / Part-time employment: Roche/Genentech. C. Flores Avile: Full / Part-time employment: Genesis Research. P. Luhn: Shareholder / Stockholder / Stock options, Full / Part-time employment: Roche/Genentech. A. Schneeweiss: Honoraria (self), Research grant / Funding (institution), Travel / Accommodation / Expenses: Celgene; Honoraria (self), Speaker Bureau / Expert testimony, Research grant / Funding (institution), Travel / Accommodation / Expenses: Roche; Research grant / Funding (institution): AbbVie; Research grant / Funding (institution): Molecular Partner; Honoraria (self), Speaker Bureau / Expert testimony: AstraZeneca; Honoraria (self), Travel / Accommodation / Expenses: Pfizer; Honoraria (self): Novartis; Honoraria (self): MSD; Honoraria (self): Tesaro; Honoraria (self): Lilly.