Company: BLLN
Filing Date: 2025-06-20
Form Type: DRS
Source: 0000950123-25-006095
Chunk: 176

Company: BillionToOne, Inc.
Filing Date: 2025-06-20
Form: DRS
Chunk 176
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 provide insight into what therapies may be
appropriate for a patient with stage III or IV cancer. Our Northstar Select test has demonstrated industry-leading performance, including two to five times lower LOD, which results in more than 50% more actionable mutations identified than
comparator products.

In 2025, the MolDX Program, which is administered by Palmetto GBA, a Medicare administrative contractor, determined Northstar Select meets the
coverage requirements under LCD L38043. The MolDX Program’s thorough review process confirms Northstar Select’s clinical validity and utility and enables reimbursement for Medicare and Medicare Advantage beneficiaries who are receiving the
test. In the future we may seek FDA approval for certain of our tests, in particular, Northstar Select, which could provide us with competitive advantages such as including enhanced reimbursement through Advanced Laboratory Diagnostic Test (ALDT)
pricing; however, it would also subject us to additional regulatory requirements, which can be costly.

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Northstar Select achieves a significantly lower 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 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.

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 0.15%, representing a 2-fold higher sensitivity
than these other assays. Since most treatable mutations occur at very low VAFs and studies have shown that even mutations found at <0.20% VAF respond to therapy, Northstar Select uncovers more treatment options for patients.

The sensitivity of other liquid biopsies is even more problematic for copy