Study to Evaluate Safety, Pharmacokinetics, and Efficacy of Rociletinib (CO-1686) in Previously Treated Mutant Epidermal Growth Factor Receptor (EGFR) in Non-Small Cell Lung Cancer (NSCLC) Patients

Inclusion Criteria - All patients must meet the following inclusion criteria: 1. Metastatic or unresectable locally advanced NSCLC 2. Evidence of a tumor with one or more EGFR mutations excluding exon 20 insertion 3. Biopsy of either primary or metastatic tumor tissue within 60 days of dosing 4. Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 1 5. Minimum age of 18 years 6. Adequate hematological and biological function 7. Written consent on an IRB/IEC-approved Informed Consent Form (ICF) prior to any study-specific evaluation Phase 2 Cohorts must also meet the following inclusion criteria: * Disease progression confirmed by radiologic assessment while on treatment with EGFR- TKI Or * Disease progression confirmed by radiologic assessment while on treatment with the first single agent EGFR TKI and * Documented evidence of T790M mutation in EGFR following disease progression on the first single agent EGFR TKI. * Measureable disease according to RECIST Version 1.1 Exclusion Criteria - Any of the following criteria will exclude patients from study participation: 1. Documented evidence of an Exon 20 insertion activating mutation in the EGFR gene 2. Active second malignancy 3. Known pre-existing interstitial lung disease 4. Patients with Leptomeningeal carcinomatosis are excluded. Other CNS metastases are only permitted if treated, asymptomatic and stable (not requiring steroids for at least 4 weeks prior to start of study treatment). 5. Treatment with prohibited medications less than or equal to 14 days prior to treatment with rociletinib 6. Patients who are currently receiving treatment with any medications that have the potential to prolong the QT interval and the treatment cannot be either discontinued or switched to a different medication before starting rociletinib 7. Prior treatment with rociletinib or other drugs that target T790M positive mutant EGFR with sparing of wild type EGFR 8. Certain cardiac abnormalities or history 9. Non-study related surgical procedures less than or equal to 7 days prior to administration of rociletinib 10. Females who are pregnant or breastfeeding 11. Refusal to use adequate contraception for fertile patients (females and males) for 12 weeks after the last dose of rociletinib 12. Presence of any serious or unstable concomitant systemic disorder incompatible with the clinical study 13. Any other reason the investigator considers the patient should not participate in the study