Cancer treatment is undergoing a quiet revolution—one that could fundamentally reshape how oncologists approach some of the most aggressive and difficult-to-treat tumors. At the heart of this transformation are next-generation antibody-drug conjugates (ADCs)—a sophisticated class of therapies that blend the precision of targeted antibodies with the power of chemotherapy.
Pfizer, a leader in oncology innovation, has emerged at the forefront of ADC development. In 2023, the pharmaceutical giant significantly expanded its capabilities with the acquisition of Seagen, pioneers of the vedotin ADC platform. This move not only bolstered Pfizer’s oncology portfolio but placed it in control of nearly half of all ADCs currently approved by the U.S. Food and Drug Administration (FDA).
A Proven Platform with Expanding Potential
At the center of Pfizer’s ADC efforts is the vedotin platform, which uses the highly potent chemotherapy agent monomethyl auristatin E (MMAE). Delivered directly into cancer cells via an antibody, MMAE disrupts microtubule formation—a vital process for cell division—ultimately causing cell death. But the technology offers more than just targeted cytotoxicity.
According to Dr. Megan O’Meara, head of early-stage development at Pfizer Oncology, “Our proprietary vedotin platform doesn’t just kill cancer cells—it helps alert the immune system, too. This dual mechanism has the potential to make ADCs far more powerful than traditional chemotherapy alone.”
From Cytotoxicity to Immune Activation
One of the most exciting aspects of Pfizer’s ADC strategy is the induction of immunogenic cell death (ICD). When an ADC kills a cancer cell, it can also trigger the release of tumor antigens and inflammatory signals, effectively waving a red flag to the immune system. This, in turn, can recruit T cells and other immune agents to the tumor site.
“ADCs that induce ICD can work synergistically with immune checkpoint inhibitors,” O’Meara explains. “Together, they can unleash the immune system’s full potential—something we believe will be critical in achieving more durable and robust anti-tumor responses.”
Beyond Traditional Payloads
While MMAE has proven highly effective, Pfizer is not stopping there. The company is actively developing next-generation payloads, including:
- Topoisomerase inhibitors that damage cancer cell DNA.
- Immune-stimulating agents that activate tumor-infiltrating immune cells.
- Protein degraders that break down key survival proteins in cancer cells.
“We’re building a multi-platform ADC strategy that goes beyond chemotherapy,” O’Meara says. “This includes the development of immune-stimulating antibody conjugates (ISACs), which not only kill cancer cells but also reprogram the tumor microenvironment.”
What’s Ahead: The AACR 2025 Annual Meeting
At the upcoming American Association for Cancer Research (AACR) 2025 Annual Meeting, Pfizer will unveil new data across several fronts of its ADC research. This includes:
- Continued progress on vedotin-based ADCs.
- Preclinical and early clinical findings for novel payloads.
- Explorations into ADC-immunotherapy combinations.
- Breakthroughs in immune-stimulating ADCs that could represent the next major leap in cancer immunotherapy.
“We’re excited to share what’s coming,” says O’Meara. “From novel payloads to immune engagement strategies, our goal is to broaden the cancers that ADCs can treat and improve outcomes for more patients.”
Looking to the Future
The ADC field is growing rapidly, and Pfizer’s deep bench of expertise—in pharmacokinetics, payload chemistry, tumor targeting, and immune biology—places the company in a unique position to lead. Over the next five to ten years, ADCs are expected to evolve from precision chemotherapies into immune-modulating powerhouses, forming the backbone of next-generation immuno-oncology regimens.
“With such a robust pipeline,” O’Meara concludes, “we’re committed to advancing the most extensive ADC portfolio in the industry to help people with cancer live longer, better lives.”
