In the biggest M&A deal since 2019, Pfizer has agreed to acquire Seagen for US$299 in cash per Seagen share, representing a total enterprise value of US$43 B and a 33% premium to Seagen’s closing price the day prior to the announcement. Seagen’s marketed cancer drugs, including top-selling antibody-drug conjugate (ADC) Adcetris® (brentuximab vedotin), strongly complement Pfizer’s existing oncology portfolio. The big pharma is under pressure to offset its projected decline in revenue, as it faces patent expirations and slower demand for COVID-19 products.