Inclusion Criteria:

- Histologically confirmed diagnosis of unresectable Stage IIIB or Stage IV relapsed or
recurrent NSCLC.

- Subjects must have:

1. documented (radiological or clinical) progressive disease (PD) following a prior
response (including stable disease) to monotherapy with erlotinib or gefitinib
that was administered for at least 12 weeks prior to progression OR

2. a documented T790M EGFR mutation

- Measurable disease defined according to RECIST

- ECOG performance status of 0 or 1.

- Sexually active subjects must use an accepted method of contraception during the
course of the study.

- Female subjects of childbearing potential must have a negative pregnancy test at
enrollment.

Exclusion Criteria:

- Received radiation to ≥25% of his or her bone marrow within 30 days of XL647
treatment.

- Received erlotinib or gefitinib, or other anticancer therapy within 14 days of the
first dose of study drug.

- Received an investigational drug (excluding erlotinib or gefitinib) within 30 days of
the first dose of study drug.

- Receiving anticoagulation therapy with warfarin.

- Not recovered to Grade ≤1 from adverse events (AEs) due to antineoplastic agents,
investigational drugs, or other medications that were administered prior to study
enrollment.

- Corrected QT interval (QTc) of >0.45 seconds.

- Progressive, symptomatic, or hemorrhagic brain or leptomeningeal metastases.

- Requires steroid or anticonvulsant therapy for the treatment of brain metastases.