Identifying predictive and surrogate markers of erlotinib antitumor activity other than rash.

The identification of predictive or surrogate markers of response to HER1/epidermal growth factor receptor (EGFR) inhibitor treatment would permit selection of patients most likely to respond to such treatment. Markers could consist of tumor characteristics (eg, characteristics of the receptor or downstream signaling molecules and determinants of resistance) or host characteristics (eg, pharmacokinetic parameters and toxicities). The occurrence of rash may constitute a surrogate marker of response to erlotinib (Tarceva) treatment in patients with non-small-cell lung cancer and other cancers. The erlotinib marker identification program has been designed to identify and investigate other candidate markers by analysis of a large number of clinical samples from patients enrolled in erlotinib trials in non-small-cell lung cancer, including the phase III TALENT and TRIBUTE trials of erlotinib combined with chemotherapy and the phase III BR.21 trial of erlotinib monotherapy in advanced non-small-cell lung cancer. This program should both contribute to understanding of the molecular biology of HER1/EGFR inhibition and result in identification of potential markers that can be evaluated in the clinical setting.