Done and dusted: Pfizer completes $43bn Seagen deal

Pfizer adds four approved therapies and a pipeline of antibody drug conjugates (ADCs) through the completion of its acquisition of Seagen.

2023 has seen a renewed interest in the ADC space from Big Pharma. AbbVie’s recent $10 billion bid for ImmunoGen may be the latest in a long string of dealmaking and expansion in the space, but the whole flurry of multi-billion-dollar activity first kicked off back in March when Pfizer agreed to acquire ADC pioneer SeaGen for $43 billion.

Nine months on and the deal has closed after Pfizer agreed on the conditions set by monopoly board the US Federal Trade Commission (FTC) to donate all future rights of US royalties from sales of urothelial carcinoma (UC) drug Bavencio (avelumab) to the American Association for Cancer Research (AACR). In 2022, Bavencio pulled in US sales of $27 million for Pfizer.

“With Seagen’s proprietary, world-leading ADC technology, together with the scale and strength of Pfizer’s capabilities and expertise, we are poised to change the cancer treatment paradigm,” said Pfizer CEO Albert Bourla.

“We believe oncology will be a significant growth driver for Pfizer and contribute meaningfully to the achievement of our near- and long-term financial goals.”

With the deal closed, Pfizer adds the approved cancer products approved cancer products Adcetris (brentuximab vedotin), Padcev (enfortumab vedotin), Tivdak (tisotumab vedotin), and Tuksya (tucatinib).

The firm also adds around 10 candidates and manufacturing sites in Bothell, Washington and a $350-400 million greenfield biomanufacturing site in nearby Everett under construction.

According to Pfizer’s latest financial guidance published this week, Seagen will contribute approximately $3.1 billion in 2024.

Nona $53m ADC deal

The completion of the deal came on the same day Pfizer further propped up its ADC pipeline through a licensing agreement with Nona Biosciences.

Under the terms of the deal, Nona will receive $53 million upfront, with the potential for up to a further $1.05 billion upon development and commercial milestones in exchange for the global clinical development and commercialization rights of MSLN-targeted antibody-drug conjugate (ADC), HBM9033.

“We are delighted to collaborate with Pfizer, a company that is committed to developing high-impact medicines for people living with cancer,” said Jingsong Wang, chairman of Nona Biosciences.

“This agreement represents a significant milestone in the advancement of our proprietary Harbour Mice platform and the ADC ecosystem, affirming Nona’s robust capabilities and expertise in antibody discovery and development.”