Fulvestrant decreases anastrozole drug concentrations when taken concurrently by patients with metastatic breast cancer treated on SWOG study S0226.

ABSTRACT:

Aims

In the SWOG S0226 trial the combination of anastrozole plus fulvestrant (n = 349) was superior to anastrozole alone (n = 345) in hormone receptor (HR)-positive metastatic breast cancer. Here we report a pharmacokinetic subset analysis investigating a possible drug interaction between anastrozole and fulvestrant.

Methods

Post-menopausal patients with HR-positive metastatic breast cancer were randomized to anastrozole with or without concurrent fulvestrant. Blood samples were collected at 2, 4, 6 and 8 months, just prior to receiving the next dose of anastrozole and fulvestrant. Drug concentrations were measured via LC/MS-MS. Anastrozole concentration was compared in patients on anastrozole alone vs. patients on concomitant fulvestrant. Comparisons were made at each time

SUBMITTER: Hertz DL 

PROVIDER: S-EPMC4876171 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature