Both boards have approved the transaction, which is expected to close in late 2023 or early 2024. Pfizer said it plans to pay for the acquisition mostly through $31 billion of new, long-term debt.

Regarding itself as a pioneer in antibody-drug conjugates (ADCs), Seagen adds four commercial drugs to Pfizer’s cancer portfolio — Adcetris, Padcev, Tukysa and Tivdak — together with a robust pipeline of ADC candidates.

“The addition of Seagen’s world-leading ADC technology will position us at the forefront of innovative cancer care, and strongly complements our existing portfolio across both solid tumors and hematologic malignancies,” said Chris Boshoff, Pfizer’s chief development officer oncology and rare disease.

Pfizer’s oncology offering comprises 24 approved medicines that generated $12.1 billion of revenue last year. The pharma giant said it expects Seagen’s drugs, which had revenues in of $2 billion in 2022, to add annual revenues of $10 million by 2030.

During a conference call on Mar. 13 to announce the acquisition, Pfizer CEO Albert Bourla said: “We are not buying the golden eggs. We are acquiring the goose that is laying the golden eggs.”

The deal is reported to be the largest biopharma acquisition since June 2019, when AbbVie paid $63 billion for Allergan. And Pfizer has been particularly acquisitive in the past couple of years, taking cancer specialists Trillium Therapeutics in November 2021 for $2.2 billion, followed in March 2022 by Arena Pharmaceuticals for $6.7 billion.

Last October, Pfizer also closed its $11.6 billion takeover of Biohaven Pharmaceuticals, as well as its $5.4 billion buyout of Global Blood Therapeutics.

Author: Elaine Burridge, Freelance Journalist