A notable example is pembrolizumab, which has been approved either as single-agent therapy instead of chemotherapy for patients with metastatic or aggressive NSCLC and ≥1% PD-L1 expression level without other actionable driver alterations (i.e., ALK, EGFR, NTRK), or in combination with chemotherapy in patients with non-squamous NSCLC for lower stage disease. Here, ALK is linked to non-small cell lung carcinoma.