Company: BLLN
Filing Date: 2025-08-11
Form Type: DRS/A
Source: 0000950123-25-007483
Chunk: 193

Company: BillionToOne, Inc.
Filing Date: 2025-08-11
Form: DRS/A
Chunk 193
---
 mother is identified as a carrier, cfDNA analysis is performed on the same blood sample to assess fetal risk. We believe directly measuring fetal risk through a single maternal blood draw is only possible with the precision and sensitivity provided by our smNGS technology. Within two weeks, the information provided to the clinician and patient includes:

| • |     | Maternal carrier status and any information about the specific variant that may be identified; |

| • |     | A personalized fetal risk score on each condition for which the pregnant mother is a carrier, ranging from <1 in 10,000 
 to 9 in 10, providing clear, actionable information for clinicians and patients; and                                    |

| • |     | Whether the risk is classified as low or high risk |

139

SUMMARY OF RESULTS A POSITIVE Carrier B LOW RISK Fetus 9.0% fetal fraction UNITY Fetal Risk Screen: Carrier Screen + cfDNA Fetal Risk Assessment C CARRIER SCREEN D cfDNA FETAL RISK ASSESSMENT (pregnant carriers only) Conditions Screened Patient Carrier Status Risk Before cfDNA Fetal Risk After cfDNA ACOG Guideline Panel Alpha-Thalassemia Negative N/A HBA1 HBA2 Cystic Fibrosis POSITIVE 1 in 96 -1 in 376 <1 in 5000 E LOW RISK Sickle Cell Disease / Beta- Thalassemia / Negative N/A Hemoglobinopathies HBB Spinal Muscular Atrophy SMN1 Negative 2 SMN1 copies, SNP not presentN/A Maternal Carrier Results Fetal Risk via cfDNA >99% of patients will be reassured with a low risk result1 Conditions screened align with ACOG recommendations2 Fetal risk is provided for this pregnancy without male partner For positive carriers, risk can be clarified down to 1 in 10,000 or up to 9 in 10 1. Internal Data on File, 2024 2. American College of Obstetricians and Gynecologists. (2017) Carrier screening in the age of genomic medicine (Committee Opinion No. 690). Obstetrics & Gynecology, 129(3), e35-e40 UNITY Fetal Risk Screen’s accuracy has been validated in multiple peer-reviewed studies. A 2023 study published in Prenatal Diagnosisdemonstrated 100% of “9 in 10” risk pregnancies were confirmed to be affected pregnancies 49. Because UNITY Fetal Risk