Company: BLLN
Filing Date: 2025-10-17
Form Type: S-1/A
Source: 0001193125-25-242632
Chunk: 227

Company: BillionToOne, Inc.
Filing Date: 2025-10-17
Form: S-1/A
Chunk 227
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., Bosch, J. R. T., 
 Palmer, G., Gajra, A., Huynh, C., & Zhou, W. (2025). Validation of a liquid biopsy assay with increased sensitivity for clinical comprehensive genomic profiling. The Journal of Liquid Biopsy, 100322.            |

| 69 |     | Ye, P. P., Viens, R., Shelburne, K. E., Langpap, et al. (2025). Molecular counting enables accurate and precise quantification of methylated ctDNA for tumor-naive cancer therapy response monitoring. Scientific Reports, 
 15(1).                                                                                                                                                                                                                     |

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(e.g., CT, MRI, and PET scans). Radiation exposure, infrequent scans, pseudo-progression with immuno-oncology therapy, and inability to precisely quantify changes, highlight some of the
limitations of an anatomic-only based approach in treatment monitoring. Our Northstar Response test is complementary to traditional imaging and introduces real-time, single-molecule quantification to treatment monitoring with a Tumor Methylation
Score (TMS). TMS is a quantitative metric that measures the extent of cancer-specific DNA methylation signal that is present in blood and reflects whether the tumor is growing or shrinking in a cancer patient when measured longitudinally. Using a
DNA methylation-based approach in conjunction with our smNGS platform, we bring a new level of precision that can help determine molecular progression or therapy response at multiple time-points over the course of a patient’s treatment.

Tumor Methylation ScoreTM Time Points Baseline Decrease Decrease Decrease Increase !Consider imaging sooner or ordering Northstar Select.

Northstar Response is highly accurate at measuring changes in tumor burden across cancer types

Our pan-cancer Northstar Response assay has been analytically validated across more than 10 tumor types and has been evaluated in
several clinical studies. In one study, we demonstrated that our assay could detect minute changes in cfDNA burden as small as 0.02% (e.g., an elevation of tumor fraction from 0.02% to 0.04%) demonstrating high sensitivity for a tissue-free, blood
only test. The assay also achieves a coefficient of variation (CV) of less than 10% for a typical sample with 1% tumor fraction, which is at least two times lower than conventional tumor-naive, targeted-panel methods that measure VAF. It has
demonstrated a strong correlation with clinical outcomes in patients with lung, colore