Tagrisso and osimertinib are the same drug — brand vs INN name, no FDA generic in USA (patent ~16 more years). Complete 2026 guide: $18,278/month cash price (same for 40mg and 80mg), Access 360 $0 copay programme, FLAURA 18.9 months PFS vs erlotinib's 10.2, ADAURA 80% recurrence reduction, T790M and blood-brain barrier advantages, ILD and QTc emergencies, 3-generation EGFR inhibitor comparison table.