AZ plummets on MYSTIC readout in NSCLC

AstraZeneca plc (LSE:AZN; NYSE:AZN) lost $12.8 billion in market cap on Thursday after it said first-line treatment with PD-L1 inhibitor Imfinzi durvalumab missed the co-primary endpoint of improving progression-free survival (PFS) in the Phase III MYSTIC trial to treat stage IV non-small cell lung cancer. AZ lost $5.06 (15%) to $28.88 in New York and lost 788p (15%) to 4,325p in London.

Compared to standard of care (SOC), Imfinzi plus CTLA-4 inhibitor tremelimumab failed to improve PFS in patients whose tumors express PD-L1 on 25% or more of their cancer cells. AZ also said Imfinzi monotherapy would not have met the prespecified threshold for PFS benefit over SOC, a secondary endpoint. MYSTIC evaluated Imfinzi in patients with previously untreated, wild-type EGFR and anaplastic lymphoma kinase (ALK), locally advanced or metastatic NSCLC...