STOP BLOQ: Preventing Fetal Heart Block

This study, called STOP BLOQ, is looking for ways to prevent a serious heart condition in unborn babies called fetal atrioventricular block (AVB). This condition, often linked to mothers with certain antibodies (anti-Ro 52 or 60), can be very dangerous. Researchers believe there might be a short window of time when a less severe form of AVB (2° AVB) can be treated before it becomes irreversible (3° AVB). The study will test two treatments: Dexamethasone, a steroid, and IVIG (intravenous immunoglobulin), which helps the immune system. Success will be measured by how many babies with 2° AVB have a normal heart rhythm at birth. You can join if you are under 18 weeks pregnant and have specific anti-Ro antibodies. The study plans to enroll 1300 participants, but its current status is unclear.

Study design
This is an interventional study, meaning participants will receive a specific treatment. It aims to enroll 1300 participants.
What's involved
Not specified in the trial record.
Compensation
Not stated in the trial record.
Follow-up
Participants will be followed to see if their baby has a normal heart rhythm at birth, measured up to 25 weeks after enrollment.

AI-generated from the public study record. Only the study team can confirm whether you're eligible — confirm details with them before making decisions.

NCT04474223

Surveillance and Treatment to Prevent Fetal Atrioventricular Block Likely to Occur Quickly (STOP BLOQ)

Active, Not Recruiting
PHASE3Ages 18+InterventionalTreatment
NYU Langone Health
~1,300 participants
Updated 2026-08-25 on ClinicalTrials.gov
What's tested:DexamethasoneIVIG

At a glance

Recruiting sites
0 of 24 listed sites are recruiting right now
RecruitingSuspended, closed, or not yet open
What they're measuring
Percentage of 2° AVB subjects with NR (1:1 AV conduction) at birth
Measured over up to 25 weeks post-enrollment
AVB - Atrioventricular Block
Fetal AVB
24 sites across 18 states
California3
New York3
Kentucky2
Ohio2
Arizona1
Colorado1
Connecticut1
District of Columbia1
  • Jill Buyon, MD · PRINCIPAL_INVESTIGATOR · NYU Langone Health
  • Bettina Cuneo, MD · PRINCIPAL_INVESTIGATOR · University of Colorado, Denver

This trial hasn't published a contact. View it on ClinicalTrials.gov

  • Percentage of 2° AVB subjects with NR (1:1 AV conduction) at birthup to 25 weeks post-enrollment

    The presence of NR (normal rhythm) will be determined by electrocardiogram (ECG)