With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Colin Firth was in Pride & Prejudice.
text_B: Erlotinib hydrochloride -LRB- trade name Tarceva -RRB- is a drug used to treat non-small cell lung cancer -LRB- NSCLC -RRB- , pancreatic cancer and several other types of cancer .. drug. medication. non-small cell lung cancer. non-small cell lung cancer. pancreatic cancer. pancreatic cancer. It is a receptor tyrosine kinase inhibitor , which acts on the epidermal growth factor receptor -LRB- EGFR -RRB- .. tyrosine kinase inhibitor. tyrosine kinase inhibitor. epidermal growth factor receptor. epidermal growth factor receptor. It is marketed in the United States by Genentech and OSI Pharmaceuticals and elsewhere by Roche .. United States. United States. Genentech. Genentech. OSI Pharmaceuticals. OSI Pharmaceuticals. Roche. Hoffmann–La Roche. In the United States as of 2015 one 150 mg pill costs between 200 and 242 USD .. United States. United States
not_related.