Pfizer doesn’t want to be left out of the arena in terms of being able to get its foot into a huge race that’s heating up amongst many biotech companies. This has to do with the mechanism of action (MOA) of using a bispecific PD-1 and VEGF antibody to target patients with a variety of types of cancers. With that being said, it inked a deal with a leading Chinese biopharmaceutical company by the name of 3SBio, Incorporated. Specifically, it is paying an upfront amount of $1.25 billion to get its hands on exclusive global rights to SSGJ-707, excluding China. Although to quickly point out, there is an option in the agreement whereby Pfizer could choose to obtain commercialization rights in China should it choose to do so. This deal does not come cheap because if it ultimately pays off, then it would also be on the hook for having to pay 3SBio an additional $4.8 billion in development, regulatory, and commercial milestone payments. Plus, the need to pay out double-digit tiered royalties on net sales of SSGJ-707 if it is ultimately approved for marketing.
The whole craze about many companies wanting to get their hands on such a PD-1/VEGF bispecific antibody is because of what Summit Therapeutics and its China partner Akeso were able to accomplish with their drug ivonescimab [also PD-1/VEGF bispecific antibody]. This specifically comes from data released from the phase 3 HARMONi-2 study that was conducted in China by Summit’s partner Akeso. It was noted that Ivonesciamb reduced the risk of disease progression or death by as much as 49% compared to that of Merck’s Keytruda. It is important to note though, that this was in the 1st-line setting (patients not previously treated) and with PD-L1 positive non-small cell lung cancer.
That wasn’t the only win either; things got really good when Akeso released data from the phase 3 HARMONi-6 trial. That’s because it was stated that after a prespecified interim analysis was done by an independent data monitoring committee, it was revealed that the primary endpoint of progression-free survival was met. This is huge because ivonescimab plus chemotherapy was pitted against Tislelizumab plus chemotherapy to treat 1st-line patients with advanced squamous non-small cell lung cancer (NSCLC). What might put this data from this study, plus the HARMONi-2 study directly above is that they were both done in China. Whether or not this raises doubts, there is no question that bispecific PD-1/VEGF antibodies are likely to have a strong presence going forward in being able to improve key metrics in treating patients with a variety of types of cancers. Even with this in mind about the data coming from China, it is not going to matter all that much, and that’s because of the ongoing phase 3 HARMONi-3 study.
This specific late-stage study is being conducted in the U.S. and a positive readout here would accomplish two things. First, it would reinforce all the prior positive data that was attained from the China studies using the PD-1/VEGF bispecific antibody ivonescimab. Secondly, with highly positive data, it would allow the company to be in a position to potentially receive U.S. marketing approval for the treatment of 1st-line metastatic NSCLC patients. While not guaranteed, an interim analysis data readout from this late-stage study is anticipated in Q4 of 2026, and then a final data readout at some point in early 2028. The point here is that Pfizer is not only going to have to contend with achieving positive data in ongoing studies, but it is also going to have to go up against a slew of other competitors in this very same space.
Merck is not just going to let Pfizer, Summit/Akeso and other companies inhibit its growth in revenue to be generated from targeting NSCLC and other types of cancers with Keytruda. With that being said, Merck paid $588 million to get its hands on LM-299, which is a bi-specific PD-1/VEGF novel investigational antibody from privately held biotech LaNova Medicines. This big pharma is expected to pay LaNova up to $2.7 billion in milestone payments should the drug pan out. Although, it appears as though this candidate has a novel molecular design with an anti-VEGF antibody linked to two C-terminal single-domain anti-PD-1 antibodies. Whether or not this is enough to overshadow competing drugs in the same space remains to be seen. Lastly, you got BioNTech, which dished out $800 million to acquire Biotheus. Along with a factor of $150 million in milestone payments as well. The reasoning here was so that it could get its hands on bispecific PD-1/VEGF antibody BNT327/PM8002 to treat a variety of types of cancers. What’s intriguing here, though is that BioNTech is appearing to do something entirely different here in terms of combinations, which could potentially pay off. It intends to combine its PD-1/VEGF bispecific together with antibody-drug conjugates (ADCs). ADCs are another drug class that has been shown to do well in targeting hematological malignancies and some solid tumors. The hope is that Pfizer’s move can pit it against all of these other companies in the latest bispecific PD-1/VEGF antibody treatment space.