Safety and Pharmacology Study of SNX-5422 in Subjects With Resistant Lung Adenocarcinoma

Inclusion Criteria:

* Males or non-pregnant, non-breastfeeding females 18 years-of-age or older.
* Received treatment with erlotinib/gefitinib throughout the one month prior to enrollment and at least six months at any time.
* Must have undergone a biopsy after the development of acquired resistance.
* Pathologic evidence of advanced lung adenocarcinoma (stage IIIB or stage IV) confirmed histologically/cytologically
* Radiographic progression by RECIST during treatment with erlotinib/gefitinib.
* Measurable (RECIST) indicator lesion not previously irradiated.
* No more than 4 prior lines of cytotoxic chemotherapy, including erlotinib/gefitinib
* Karnofsky performance score ≥70.
* Adequate baseline laboratory assessments, including

  * Absolute neutrophil count (ANC) ≥1.5 x 109/L.
  * WBC \>3000/microliter
  * Platelet count of ≥100 x 109/L.
  * Total bilirubin level ≤1.5 times institutional upper limit of normal (ULN), alanine aminotransferase (ALT) or aspartate aminotransferase (AST) ≤1.5 x ULN.
  * Hemoglobin ≥9 mg/dL.
  * Creatinine \<1.5 X upper limit of normal or estimated plasma creatinine clearance of ≥40 mL/min (using the Cockroft-Gault equation)
* Signed informed consent form (ICF).
* Subjects with reproductive capability must agree to practice adequate contraception methods.
* Adequate venous access.

Exclusion Criteria:

* CNS metastases which are symptomatic and /or requiring escalating doses of steroids.
* Prior treatment with any Hsp90 inhibitor.
* Conventional chemotherapy, radiation or monoclonal antibodies within 4 weeks (erlotinib/gefitinib therapy within the past 4 weeks IS allowed).
* Palliative radiation within 2 weeks.
* The need for treatment with medications with clinically-relevant metabolism by the cytochrome P450 (CYP) 3A4 isoenzyme within 3 hours before or after administration of SNX-5422
* Screening ECG QTc interval ≥470 msec for females, ≥450 msec for males.
* At increased risk for developing prolonged QT interval, including hypokalemia or hypomagnesemia, unless corrected to within normal limits prior to first dose of SNX-5422; congenital long QT syndrome or a history of torsade de pointes; currently receiving anti-arrhythmics or other medications that may be associated with QT prolongation.
* Patients with chronic diarrhea or with grade 2 or greater diarrhea despite maximal medical management.
* Gastrointestinal diseases or conditions that could affect drug absorption, including gastric bypass.
* Gastrointestinal diseases that could alter the assessment of safety, including irritable bowel syndrome, ulcerative colitis, Crohn's disease, or hemorrhagic coloproctitis.
* History of documented adrenal dysfunction not due to malignancy.
* Known seropositive for human immunodeficiency virus (HIV) or hepatitis C virus (HCV).
* History of chronic liver disease.
* Active hepatitis A or B.
* Current alcohol dependence or drug abuse.
* Use of an investigational treatment from 30 days prior to the first dose of SNX-5422 and during the study.
* Glaucoma, retinitis pigmentosa, macular degeneration, or any retinal changes detected by ophthalmological examination.
* Other serious concurrent illness or medical condition.
* Psychological, social, familial, or geographical reasons that would hinder or prevent compliance with the requirements of the protocol or compromise the informed consent process.