Pfizer's Latest PD-1/VEGF Play: A $6B Bet on 3SBio's Bispecific Antibody

Pfizer has made a significant move in the increasingly competitive PD-1/VEGF bispecific antibody space, announcing a $6 billion licensing deal with Chinese biotech 3SBio for its SSGJ-707 candidate. The agreement, revealed on Monday evening, marks Pfizer's latest effort to establish a strong foothold in this emerging therapeutic modality.

Deal Structure and Financial Details

Under the terms of the agreement, Pfizer will pay $1.25 billion upfront to 3SBio, with the potential for up to $4.8 billion in additional development, regulatory, and commercial milestones. The deal also includes tiered double-digit royalties on potential future sales of SSGJ-707. This substantial investment underscores Pfizer's commitment to expanding its oncology portfolio and capitalizing on the growing interest in PD-1/VEGF bispecific antibodies.

SSGJ-707: A Promising Asset

SSGJ-707 is a bispecific antibody targeting both PD-1 and VEGF pathways, currently being evaluated for various solid tumors, including non-small cell lung cancer, metastatic colorectal cancer, and gynecological tumors. 3SBio plans to initiate late-stage development of the asset in China this year, signaling confidence in its potential.

Market Context and Competitive Landscape

The PD-1/VEGF bispecific antibody field has seen increased activity in recent months, with several major pharmaceutical companies vying for position. Notable developments include:

1. BioNTech's acquisition of Biotheus and its PD-1/VEGF bispecific antibody for up to $950 million in November.
2. Merck's $588 million upfront payment to LaNova Medicines for a similar asset.
3. Summit Therapeutics and Akeso's ivonescimab outperforming Merck's Keytruda in a late-stage NSCLC study last September.
4. Ivonescimab's recent approval in China after demonstrating superiority over BeiGene's Tevimbra.

Strategic Implications and Industry Reactions

BMO Capital Markets analysts have expressed some confusion regarding Pfizer's overall strategy in the PD-1/VEGF space. The deal with 3SBio comes just three months after Pfizer entered into a clinical trials collaboration with Summit Therapeutics to test ivonescimab alongside Pfizer's antibody-drug conjugates.

The analysts noted that while the deal "shows clear appreciation for the [PD-1/VEGF] mechanism" and "builds on a surge in recent interest," questions remain about how Pfizer plans to reconcile these two separate collaborations and whether there is a risk of cannibalization between the assets.

BMO also pointed out that the total potential investment in the 3SBio deal appears to be priced at a premium compared to other recent PD-1/VEGF transactions, suggesting that Pfizer may be "paying the fee for being late to a new market."

As the pharmaceutical industry continues to explore the potential of PD-1/VEGF bispecific antibodies, Pfizer's latest move demonstrates its determination to secure a leading position in this promising therapeutic area. The closing of the deal, expected in the third quarter of this year, will be subject to regulatory clearances, shareholder approval, and other customary closing conditions.