This study employs a modified continual reassessment method (mCRM) design to estimate the maximum tolerated dose (MTD) of PF-05230907, defined as a target toxicity rate of 15% based on treatment emergent thromboembolic and/or ischemic events (TIEs). The mCRM design utilizes Bayesian methodology to continuously learn the dose-toxicity relationship, which is characterized by a parametric model.