Cellular Therapy and Antibody-Drug Conjugates Shape Day 1 of ASCO Breakthrough 2026

Innovation in cellular therapy, antibody-drug conjugates (ADCs), and precision oncology set the tone for Day 1 of the 2026 ASCO Breakthrough Annual Meeting, where global experts highlighted how rapidly cancer treatment continues to evolve across both solid tumors and hematologic malignancies.

One of the day's dominant themes was the continued expansion of antibody-drug conjugates, with multiple sessions illustrating how these targeted therapies are reshaping cancer care well beyond their initial indications.

David R. Gandara, MD, opened the discussion with a comprehensive overview of the rapidly evolving role of ADCs in lung cancer.¹ His presentation traced the remarkable evolution of the field, reviewing how improvements in target selection, linker technology, payload design, and combination strategies have expanded therapeutic options for patients while laying the foundation for the next generation of ADC development.

Gandara is chief medical officer of International Society of Liquid Biopsy, co-director of the Center for Experimental Therapeutics in Cancer, senior advisor to director at UC Davis Comprehensive Cancer Center, adjunct clinical professor of the Translational and Clinical Research Program at University of Hawaii Cancer Cetner, and professor emeritus at UC Davis Health Comprehensive Cancer Center.

That discussion continued in breast oncology, where Naoto T. Ueno, MD, PhD, FACP, reviewed the growing impact of ADCs across breast cancer subtypes.² As the therapeutic landscape continues to expand, he highlighted how these agents are increasingly moving earlier in treatment algorithms while offering new opportunities to personalize care through biomarker-driven patient selection.

Ueno is director of University of Hawai’i Cancer Center, as well as professor in the department of Medicine at John A. Burns School of Medicine and University of Hawai’i Cancer Center at the University of Hawai’i at Mānoa.

Taking an even broader perspective, Lillian L. Siu, MD, FASCO, FRCPC, examined the global ADC ecosystem, emphasizing that advances in ADC development extend far beyond individual drugs.³ She described a rapidly maturing field driven by international collaboration among academic investigators, pharmaceutical developers, translational scientists, and regulatory agencies. The discussion underscored how innovation in ADC technology is accelerating simultaneously across multiple tumor types and therapeutic platforms.

Siu is senior medical oncologist, director of the Phase I Clinical Trials Program, codirector of the Robert and Maggie Bras and Family Drug Development Program, clinical lead for the Tumor Immunotherapy Program, and the BMO Chair in Precision Cancer Genomics at the Princess Margaret Cancer Centre, University Health Network in Toronto, Canada.

Another important focus of day 1 centered on early colorectal cancer, where investigators discussed how molecular diagnostics and circulating tumor DNA are beginning to refine treatment decisions following surgery. Rather than relying exclusively on traditional clinicopathologic risk factors, ongoing research is evaluating whether molecular assessment can better identify patients who require treatment intensification while safely reducing therapy for others. These efforts reflect a broader movement toward increasingly personalized management in early-stage disease.

Precision medicine also remained a central theme in hematologic malignancies through discussions surrounding menin inhibitors. Presentations reviewed the expanding clinical experience with these targeted agents in genetically defined subsets of acute myeloid leukemia, particularly KMT2A-rearranged and NPM1-mutated disease. Beyond encouraging efficacy data, investigators focused on key unanswered questions involving resistance mechanisms, combination strategies, and the potential role of these therapies earlier in the disease course.

The future of cellular therapy represented another major highlight throughout the day. Francesca L. Lim, MBBS, reviewed the remarkable progress achieved with CAR T-cell therapy while candidly addressing the biologic challenges that continue to limit its application in T-cell malignancies.⁴ Shared antigen expression, T-cell fratricide, product contamination, and prolonged T-cell aplasia remain important barriers to broader success. However, she highlighted several innovative strategies, including gene editing, novel antigen discovery, and next-generation cellular engineering, that may help overcome these obstacles.

Lim is senior consultant hematologist at Singapore General Hospital, chief medical officer at the Advanced Cell Therapy and Research Institute Singapore, and deputy head of the Singhealth Duke-NUS Cell Therapy Center.

Building on this theme, Bor-Sheng Ko, MD, PhD, provided a comprehensive overview of the rapidly evolving treatment landscape for diffuse large B-cell lymphoma.⁵ His presentation illustrated how CAR T-cell therapy, bispecific antibodies, and other emerging immunotherapies are reshaping management across multiple lines of therapy. Rather than viewing these modalities as competing approaches, the discussion emphasized how future treatment strategies will likely integrate multiple immune-based therapies to maximize durable responses while individualizing care for each patient.

Ko is associate professor at National Taiwan University College of Medicine and director of the Department of Hematological Oncology at the National Taiwan University Cancer Center.

Collectively, day 1 highlighted a common direction across oncology. Whether through increasingly sophisticated ADCs, molecularly targeted therapies such as menin inhibitors, or next-generation cellular therapies, the field continues to move toward treatments that are both more biologically precise and more personalized.

As ASCO Breakthrough 2026 continues, these advances reinforce a broader shift in cancer medicine from treating diseases according to where they originate to tailoring therapy based on the unique biology driving each patient's cancer.

References

1. Gandara DR. Antibody-drug conjugates in lung cancer. Presented at: 2026 ASCO Breakthrough Annual Meeting; Singapore and Online; June 25-27, 2026.
2. Ueno NT. Antibody-drug conjugates in breast cancer. Presented at: 2026 ASCO Breakthrough Annual Meeting; Singapore and Online; June 25-27, 2026.
3. Siu LL. The global antibody-drug conjugate ecosystem. Presented at: 2026 ASCO Breakthrough Annual Meeting; Singapore and Online; June 25-27, 2026.
4. Lim FL. Recent updates in hematologic malignancies. Presented at: 2026 ASCO Breakthrough Annual Meeting; Singapore and Online; June 25-27, 2026.
5. Ko BS. Recent updates in hematologic malignancies: considerations in Asia-Pacific region. Presented at: 2026 ASCO Breakthrough Annual Meeting; Singapore and Online; June 25-27, 2026.