The landscape of modern oncology is currently defined by a multibillion-dollar gamble. Pharmaceutical giants and agile biotech firms alike have pivoted their R&D focus toward a promising class of therapeutics known as PD-1/VEGF bispecific antibodies. This class of drugs, designed to simultaneously engage the immune system and starve tumors of their blood supply, has become the industry’s "holy grail" following a series of high-profile clinical successes—most notably the 2024 trial results of ivonescimab, which demonstrated superiority over Merck’s titan, Keytruda, in lung cancer.
Yet, as the fervor intensifies and capital flows into massive licensing deals, a shadow of skepticism is beginning to emerge. While the industry’s eyes are locked on the lucrative lung cancer market, leading analysts suggest that this narrow focus may be a strategic miscalculation. The true potential of these bispecifics, they argue, lies not in the crowded corridors of thoracic oncology, but in biological pathways where VEGF signaling plays a more central, oncogenic role.
A Chronology of the Bispecific Boom
The current gold rush did not emerge in a vacuum. It is the culmination of decades of research into the tumor microenvironment.
- 2024: The Breakthrough: The pivotal moment arrived when ivonescimab, developed by Akeso and licensed to Summit Therapeutics, outperformed the standard-of-care immunotherapy Keytruda (pembrolizumab) in a lung cancer trial. This result sent shockwaves through the market, proving that a single molecule could potentially outperform the most successful cancer drug in history.
- 2025: The Global Reality Check: By May 2025, the picture became more nuanced. While Summit’s global Phase 3 trials showed progress in progression-free survival for EGFR-mutant non-small cell lung cancer (NSCLC), the reduction in death risk compared to chemotherapy was not statistically significant. This "split verdict" served as a cooling agent for the industry’s initial euphoria.
- 2026: The Strategic Pivot: As of early 2026, companies like AbbVie have entered into exclusive licensing agreements—such as their partnership with RemeGen—to develop novel bispecifics for solid tumors, signaling that the industry is still doubling down on the technology even as they diversify their targets beyond the lung.
Supporting Data: The Demographic Divide
The enthusiasm surrounding PD-1/VEGF bispecifics is largely rooted in positive data from China-based trials. In a high-impact study presented to the oncology community, ivonescimab was shown to cut the risk of death in lung cancer patients by 34% compared to traditional chemotherapy combined with a standard PD-1 inhibitor.
However, Souro Chowdhury, a senior business analyst at Lifescience Dynamics, warns that these localized successes may suffer from "geographic bias." The patient populations in Chinese trials differ significantly from those in the West.
"In China, a lot of these trials have enrolled patients who are almost exclusively male and ex or current smokers," Chowdhury explains. Data from the Phase 3 ivonescimab trial reveals that roughly 93% of the study participants were male with a median age of 64.
In contrast, the patient demographic in the United States and Europe is significantly more diverse, often younger, and includes a higher percentage of non-smokers and different genetic subtypes of lung cancer. When these variables are introduced, the clinical outcomes observed in Shanghai or Beijing may not translate directly to a clinical setting in Chicago or Berlin. This demographic mismatch is a primary driver of the "split verdict" that emerged in the global 2025 trial data.
Evaluating the Mechanism: Why Lung Cancer May Not Be the Best Fit
While lung cancer represents a massive addressable market—often the primary motivation for pharmaceutical boardrooms—Chowdhury suggests that the PD-1/VEGF mechanism might be fundamentally better suited for other pathologies.
The dual-action nature of these drugs targets two distinct pathways:
- PD-1 Inhibition: Releasing the "brakes" on T-cells to attack the tumor.
- VEGF Inhibition: Blocking the formation of new blood vessels that feed the tumor.
"There’s a lot of excitement about their application in lung cancer, but that’s not necessarily the right or the best indication for this type of drug," Chowdhury states. In cancers such as hepatocellular carcinoma (liver cancer) and certain gastric cancers, the VEGF pathway is the primary driver of tumor survival and metastasis. By focusing on lung cancer—where the disease is often driven by heterogeneous mutations and immune evasion tactics—developers may be using a high-precision tool on the wrong target.
Industry Response and Strategic Diversification
The pharmaceutical industry, typically slow to pivot, is showing signs of acknowledging these limitations. Major players are beginning to hedge their bets by expanding their trial portfolios.
BioNTech’s pumitamig, which targets VEGF and PD-L1, is currently the subject of a global strategic partnership with Bristol Myers Squibb. Notably, the drug is being tested not just in lung cancer, but across a spectrum of challenging tumor types including breast, colorectal, and liver cancers.
Similarly, ivonescimab is moving into Phase 3 testing for colorectal cancer. This migration toward "second-tier" indications is being interpreted by market observers in two distinct ways:
- The Optimistic View: Companies have gained enough confidence from their lung cancer data to believe that the drug is safe and effective enough to expand into other, equally lethal indications.
- The Pragmatic View: Companies are de-risking their portfolios. Given the shaky results in global lung cancer trials, they are looking for "Plan B" indications to protect the massive valuations associated with their acquisition of these bispecific platforms.
Implications for the Future of Oncology
The trajectory of PD-1/VEGF bispecifics offers a masterclass in the complexities of modern drug development. It highlights the tension between the commercial necessity of targeting the "biggest market" (lung cancer) and the scientific necessity of targeting the "most biologically appropriate" pathway.
For patients, the implications are profound. If the industry succeeds in proving these drugs in liver or gastric cancers, it could provide a much-needed breakthrough for patients who currently have few effective treatment options. However, if the current, singular focus on lung cancer persists without addressing the demographic and biological differences in global populations, we may see a series of high-profile failures that stall the development of this promising class of medicines.
As we look toward the next three years of clinical data readouts, the industry must move beyond the "one-size-fits-all" model. The success of these bispecifics will ultimately depend on a more granular understanding of tumor biology—identifying not just where the biggest market is, but where the drug’s mechanism of action can be most lethal to the cancer, rather than the budget.
"We need to see more data, and we need to see some of these global trials read out over the next few years to really see whether this is applicable on a global stage or not," Chowdhury concludes. Until then, the multi-billion dollar bet continues, with the industry waiting to see if their scientific intuition matches the harsh reality of global clinical outcomes.
