Erlotinib is a targeted tablet for non-small cell lung cancer whose cells carry a change (mutation) in the EGFR gene. It is used as a first treatment for metastatic EGFR-mutant lung cancer, as maintenance after chemotherapy, and — with gemcitabine — for pancreatic cancer that has spread.
It was one of the first EGFR inhibitors and works by sitting in the receptor's signalling pocket and blocking the growth message the mutation has jammed on. Newer drugs such as osimertinib are now often preferred where available, but erlotinib remains widely used and is available as low-cost generics.
Erlotinib is taken once a day on an empty stomach. An acne-like rash and diarrhoea are the expected side effects; smoking lowers its blood levels substantially. It is a prescription-only medicine; a valid prescription must be provided at checkout.