- Post-menopausal women (>=18 years of age) with proven diagnosis of advanced carcinoma
of the breast (ER(+) and/or PgR(+) and HER2(-)) who are appropriate for letrozole
therapy (in the first-line advanced/metastatic disease setting).
- Eastern Cooperative Oncology Group (ECOG) performance status 0-2.
- Adequate bone marrow, liver, and renal function.
- Prior treatment with any CDK inhibitor .
- QTc >480 msec; history of QT syndrome, Brugada syndrome or known history of QTc
prolongation, or Torsade de Pointes.
- High cardiovascular risk, including, but not limited to myocardial infarction,
severe/unstable angina, severe cardiac dysrhythmias, and symptomatic pulmonary
embolism in the past 6 months of enrollment.