Study of Oral RXDX-101 in Adult Patients With Locally Advanced or Metastatic Cancer Targeting NTRK1, NTRK2, NTRK3, ROS1, or ALK Molecular Alterations.

Key Inclusion Criteria: * Histologically or cytologically confirmed diagnosis of locally advanced or metastatic solid tumors that have a NTRK1, NTRK2, NTRK3, ROS1, or ALK molecular alteration. * Measurable disease according to RECIST version 1.1. * Prior cancer therapy is allowed, including crizotinib, ceritinib, and investigational drugs. * Prior radiotherapy is allowed * Patients with controlled asymptomatic central nervous system involvement are allowed. * Resolution of all acute toxic effects (excluding alopecia) of any prior anti-cancer therapy to National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) Version 4.03 Grade less than or equal to 1. * Eastern Cooperative Oncology Group (ECOG) performance status (PS) ≤ 2. * Adult patients age 18 years or older. * Life expectancy of at least 3 months. Key Exclusion Criteria: * Current participation in another therapeutic clinical trial. * Prior treatment with entrectinib. * History of prolonged QTc interval (e.g., repeated demonstration of a QTc interval \> 450 milliseconds). * History of additional risk factors for torsade de pointes (e.g., family history of long QT syndrome). * Known active infections (bacterial, fungal, viral including HIV positivity). * Gastrointestinal disease (e.g., Crohn's disease, ulcerative colitis, or short gut syndrome) or other malabsorption syndromes that would impact on drug absorption. * Known interstitial lung disease, interstitial fibrosis, or history of tyrosine kinase inhibitor-induced pneumonitis. * Peripheral neuropathy ≥ Grade 2.