Company: BLLN
Filing Date: 2025-10-17
Form Type: S-1/A
Source: 0001193125-25-242632
Chunk: 224

Company: BillionToOne, Inc.
Filing Date: 2025-10-17
Form: S-1/A
Chunk 224
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 limit of detection than other liquid biopsy products Liquid biopsy tests are dependent on finding tumor molecules circulating in blood that are shed from tumor cells. The tumor shedding rate is highly variable, with many cancers shedding very little ctDNA. This poses a sensitivity challenge for liquid biopsies, especially for variants at low levels, and can lead to potential false-negative results and missed treatment opportunities. The amount of a particular SNV or alteration compared to normal DNA detected by liquid biopsy tests are measured as a variant allele fraction (VAF), with over half of all

| 63 |     | GBD 2021 Cancer Collaboration. Global burden of cancer and associated risk factors in 204 countries and territories, 1980-2021: a systematic analysis for the Global Burden of Disease Study 2021. Lancet Oncol. |

| 64 |     | Bower, X., Wignall, J., Varga, M. G., Zhu, J., O’Sullivan, M., Searle, N. E., Hong, L. K., Dogruluk, T., Li, Z., Farmer, T. E., Rosas-Linhard, E., Luong, J., Lin, E., Simon, M. E., Tsao, D. S., 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.            |

| 65 |     | More than 50% more actionable/reportable mutations when compared to the comparator products in the aggregate. Actual percentages may vary depending on the individual comparator test. |

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treatable alterations occurring at a VAF <0.5%, and approximately one fourth occurring at <0.2%. The ability to reliably detect more alterations at a lower VAF is a significant area of unmet clinical need for ctDNA-based testing and an opportunity for technological improvement. Above 0.5% VAF Below 0.5% VAF Below 0.2% VAF The limit of detection (LOD) is the lower bound limit of an assay’s ability to reliably detect alterations at a specific VAF, at a 95% sensitivity. First generation liquid biopsy tests have an LOD that ranges between 0.25%—0.50%, whereas Northstar Select has demonstrated an LOD of