Personalis and Collaborators to Highlight Ultrasensitive ctDNA Data and New Therapy Resistance Tracking Capabilities at AACR 2026

Key Takeaways

• Real‑Time Variant Tracker monitors resistance mutations during MRD testing
• NeXT Personal detects ctDNA below 10 parts per million
• Oral presentation shows ctDNA predicts response to neoadjuvant pembrolizumab
• Posters present analytical validation and real‑world data for ESR1 tracking
• Data highlights potential to guide patient management after cancer recurrence

Pulse Analysis

The upcoming American Association for Cancer Research (AACR) meeting provides a high‑visibility platform for Personalis to demonstrate how its NeXT Personal assay pushes the limits of circulating tumor DNA (ctDNA) detection. By achieving sensitivity below 10 parts per million, the test can identify minimal residual disease (MRD) in patients whose tumor burden is otherwise undetectable. This level of granularity is especially valuable in colorectal cancer, where early detection of residual disease can influence decisions about adjuvant therapy and surveillance.

A standout feature of Personalis’ portfolio is the newly introduced Real‑Time Variant Tracker. Unlike static MRD assays, this capability continuously monitors emerging resistance mutations—such as ESR1—in the same blood sample over time. The ability to flag therapeutic escape mechanisms as they arise offers oncologists a proactive tool to switch or combine treatments before clinical relapse becomes apparent. Early data presented in poster form suggest robust analytical validation and real‑world case studies, underscoring the assay’s potential to serve both diagnostic and drug‑development applications.

From a market perspective, integrating dynamic resistance tracking into a liquid‑biopsy platform differentiates Personalis in a crowded precision‑oncology space. Competitors are racing to add similar features, but Personalis’ tumor‑informed approach and proprietary algorithms may provide a defensible edge. Successful adoption could accelerate reimbursement discussions and expand the test’s footprint beyond academic centers into community oncology practices, ultimately driving revenue growth while supporting personalized treatment pathways for patients across multiple solid‑tumor types.