Inclusion Criteria:

          -  Patients with a diagnosis of cytologically or histologically documented adenocarcinoma
             of the lung with either metastatic disease (stage IV), Stage IIIB or Stage IIIC
             disease not amenable to surgery with curative intent

          -  Not received more than 2 prior systemic therapies- one of which must have been a
             platinum based regimen- for primary or recurrent disease

          -  Tissue submitted for HRG-biomarker testing

          -  ECOG performance status (PS) of 0 or 1

        Exclusion Criteria:

          -  Known ALK mutation

          -  Presence of exon 19 deletion or exon 21 (L858R) substitution of the EGFR gene

          -  Received >2 prior systemic anti-cancer drug regimen for locally advanced disease

          -  Prior treatment with an anti-ErbB3 antibody

          -  CTCAE grade 3 or higher peripheral neuropathy

          -  Symptomatic CNS metastases or CNS metastases requiring steroids

          -  Any other active malignancy requiring systemic therapy

          -  Clinically significant cardiac disease