Company: BLLN
Filing Date: 2025-10-07
Form Type: S-1
Source: 0001193125-25-233697
Chunk: 208

Company: BillionToOne, Inc.
Filing Date: 2025-10-07
Form: S-1
Chunk 208
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early-stage cancer testing. We are developing additional oncology products for these cancer patients, including MRD testing. Current standard of care for early-stage cancer is the surgical removal of the tumor. However, a small number of cancer
cells may remain and can lead to future metastasis. MRD testing post-surgery enables healthcare providers to administer adjuvant therapy when needed and can also be used to monitor cancer recurrence over time. There are two approaches to MRD testing
today, tumor-informed and tumor-naive. Tumor-informed approaches involve sequencing the cancer tissue to identify mutations which can then be tracked in blood at subsequent points in time. Tumor-informed approaches can have up to 40% failure rates
due to the limited amount of tissue that can be obtained in early-stage cancers or tissue sequencing failing to identify a sufficient number of variants that can be used for MRD tracking. Moreover, the mutations that are tracked may not represent
the evolution of the tumor, resulting in false negatives. Tumor-naïve approaches measure the levels

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of ctDNA in a patient’s blood and do not require an upfront tissue sample, but to date, their lower sensitivity has been a limiting factor in their adoption. We believe that our smNGS
platform will allow our planned MRD test to address the sensitivity challenges of existing tumor-naïve assays.

Our Product Portfolio

Our proprietary
smNGS platform enables us to create differentiated, ultrasensitive tests that approach the physical limit of detection (LOD). Our product portfolio touches everyone from the beginning of life, with prenatal genetic testing, to the end of life, with
cancer therapy selection and response monitoring testing.

To date, we have launched multiple differentiated products across these large addressable markets. We
performed approximately 508,000 smNGS-based tests in the last 12 months ended June 30, 2025, with significant room to further grow test volume in both markets.

PRENATAL ij UNITY 2019 2020 2021 << Fetal Risk Screen The only commercial single-gene NIPT in US for recessive conditions Aneuploidy NIPT + RhD NIPT NIPT for T21, 18, 13, and sex aneuploidies with opt-in RhD NIPT << Fetal Antigen NIPT The only commercial red blood cell NIPT in US for D, Kell, C/C, E, and Duffy ONCOLOGY NORTHSTAR 2023 2023