Abstract
We performed a clinical trial in patients with non-muscle-invasive (NMI) urothelial cancer randomized (2:1) to the EGFR tyrosine kinase inhibitor erlotinib or placebo (either orally once weekly × 3 doses prior to scheduled surgery) to assess for a difference in EGFR phosphorylation in tumor-adjacent normal urothelium <24 hours post-study dose and tolerance of weekly erlotinib therapy. Thirty-seven volunteers (6 female/31 male; mean age 70; 35 White/2 non-White) with confirmed or suspected NMI urothelial cancer were enrolled into either erlotinib (n = 24; 900 mg-13, 600 mg-11) or placebo (n = 13). IHC assessment of phosphorylated and total EGFR in tumor-adjacent normal urothelium (20 erlotinib and 9 placebo subjects) or tumor (21 erlotinib and 11 placebo subjects) at study end showed no significant difference between those receiving erlotinib or placebo. This was also true for other assessed tissue biomarkers (phosphorylated ERK, ERK, E-cadherin, p53, and Ki67). Adverse events were more common, in a dose-related fashion, in participants receiving erlotinib, e.g., 38% experienced grade 1 with rare grade 2 diarrhea and skin toxicity versus 8% in placebo. Clinically insignificant but statistically significant (P = 0.001) elevations in serum total bilirubin and creatinine were observed in participants receiving erlotinib. Serum erlotinib and metabolite concentrations (OSI-420) confirmed compliance in all subjects receiving erlotinib and did not significantly differ between the 600 and 900 mg doses. Despite compelling preclinical and clinical data for targeted EGFR inhibition in bladder cancer prevention, these data do not support the use of weekly erlotinib therapy to prevent progression of NMI bladder cancer. Prevention Relevance: We evaluated the potential of erlotinib in preventing cancer by performing a randomized, double-blind, placebo-controlled trial of weekly erlotinib therapy in participants undergoing surgical removal of suspected noninvasive bladder neoplasia. Weekly erlotinib therapy was tolerated with common grade 1 to 2 toxicities but without evidence of beneficial effect upon urothelial tissue. See related Spotlight, p. 7.