Company: BLLN
Filing Date: 2025-10-17
Form Type: S-1/A
Source: 0001193125-25-242632
Chunk: 233

Company: BillionToOne, Inc.
Filing Date: 2025-10-17
Form: S-1/A
Chunk 233
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 case studies: Identifying cystic fibrosis during routine screening Study 1: A patient with no prior knowledge of being a carrier for cystic fibrosis (CF) underwent routine prenatal testing, which revealed she was a carrier of CF. The couple, neither with a family history of CF, initially had a general population risk for CF of one in 3,000 to one in 6,000. However, within approximately two weeks of sample collection, results from UNITY Fetal Risk Screen indicated a nine in 10 chance of the baby being affected with CF through homozygous inheritance of delta F508, leading the patient to opt for amniocentesis and a prenatal diagnostic confirmation of CF. Subsequently, the mother received TRIKAFTA (elexacaftor/tezacaftor/ivacaftor and ivacaftor) treatment during pregnancy, and the baby was able to receive further treatment at just two weeks old. This case demonstrates how UNITY Fetal Risk Screen’s personalized fetal risk assessment enabled timely intervention and specialist referrals that may not have been possible with traditional carrier screening, which often has delays and lower partner participation rates. Study 2: In a similar case, a patient who presented with echogenic bowel on ultrasound was identified as a CF carrier with sgNIPT showing a 9 in 10 chance of the baby being affected with CF. The amniocentesis confirmed the diagnosis. After referral to a pulmonologist, the patient received TRIKAFTA during pregnancy, starting at 27 weeks of gestation. Despite earlier ultrasound findings, the baby was able to be discharged without a neonatal intensive care unit stay and passed newborn screening (NBS) for CF. It is extremely rare for a newborn with CF to pass NBS. Given the echogenic bowel on ultrasound during pregnancy, early diagnosis by UNITY and subsequent treatment enabled this newborn to have a significantly better outcome and avoid a potentially lengthy NICU stay. 167

UNITY Fetal Antigen NIPT patient case study: Assessing big C alloimmunization risk for streamlined care

During routine prenatal lab work, a pregnant patient was found to be alloimmunized to the big C antigen. The patient’s
OB-GYN ordered UNITY Fetal Antigen NIPT at 14 weeks gestation to assess the fetal antigen status of the pregnancy. UNITY Fetal Antigen NIPT revealed a “not detected” result, indicating that the
baby did not express the big C antigen and the pregnancy was not at risk for