Interferon Gamma mRNA Signature in Tumor Biopsies Predicts Outcomes in Patients with Non–Small-Cell Lung Carcinoma or Urothelial Cancer Treated with Durvalumab

An unmet need in cancer treatment is identification of biomarkers of response to PD-1 or PD-L1 immune checkpoint inhibitors that predict therapeutic outcomes in patients with non–small-cell lung carcinoma (NSCLC) and urothelial cancer (UC). Expression of PD-L1 measured by immunohistochemistry has limited capacity for predicting outcomes of immune checkpoint therapy because expression of this biomarker does not correlate highly with treatment response. In addition, PD-L1 as measured on tumor cells, which has been approved by the FDA for both companion and complementary diagnostic utility, does not necessarily reflect anti-tumor activity of tumor-infiltrating lymphocytes. Results presented in this report demonstrate that gene expression levels of four interferon gamma (IFNγ)-inducible mRNAs correlate with improved clinical outcomes in patients with NSCLC or UC treated with the PD-L1 inhibitor durvalumab. This IFNγ gene signature may augment the predictive value of PD-L1 and other biomarkers in identifying cancer patients most likely to respond to therapy with durvalumab or other immune checkpoint inhibitors. RNA sequencing of 97 biopsies from a nonrandomized phase 1b/2 clinical trial (1108/NCT01693562) were profiled to identify a predictive signature; 62 locally advanced or metastatic urothelial cancer (UC) tumors from the same study were profiled to confirm predictive utility of the signature.