Observational Study of Heart Rhythms with BTK Inhibitors or Venetoclax

This study is looking at how certain cancer medications, called BTK inhibitors (BTKi), might affect your heart rhythm. BTKi are used to treat chronic lymphocytic leukemia (CLL), Waldenstrom's macroglobulinemia, and mantle cell lymphoma. Researchers want to understand if these drugs increase the risk of abnormal heart rhythms and sudden death. They are also studying venetoclax, another cancer medication, which is not thought to have these heart effects. The main goal is to identify and track any heart rhythm problems that occur within the first 12 months of BTKi treatment. This is an observational study, meaning researchers will watch what happens to people already taking or planning to take these medications. The study aims to enroll 135 participants, but its current status is unclear.

Study design
This is an observational study, meaning participants will be monitored while receiving their standard treatment. It is not specified if it's randomized or blinded, and it aims to enroll 135 participants.
What's involved
If you haven't started BTKi, you'll have two clinic visits: one before starting and one about six months later. If you're already taking BTKi, you'll have one visit. These visits include a physical exam, blood, and saliva collection.
Compensation
Not stated in the trial record.
Follow-up
The primary endpoint measures heart effects and sudden death within the first 12 months of BTKi therapy.

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

NCT05724121

Observational Study of Cardiac Arrhythmias During Treatment With BTK Inhibitors or Venetoclax

Recruiting
Not specifiedAges 18+Observational
National Heart, Lung, and Blood Institute (NHLBI)
~135 participants
Updated 2026-08-07 on ClinicalTrials.gov

At a glance

Recruiting sites
1 of 1 listed site is recruiting right now
RecruitingSuspended, closed, or not yet open
What they're measuring
arrhythmogenic cardiac effects of BTKi and sudden death within the first 12 months of BTKi therapy
Measured over 12 months
Chronic Lymphocytic Leukemia (CLL)
Waldenstr(SqrRoot)(Delta)m s Macroglobulinemia
Mantle Cell Lymphoma
Sudden Cardiac Death
Cardiac Arrhythmias
Hematologic Malignancies

NCT05724121

Where you'd take part

This study runs at 1 site. They're the same protocol — you choose where, and that choice sets who your contact draft is addressed to.

  • National Institutes of Health Clinical Center

    Bethesda, Marylandstudy coordinator listed

    Recruiting

Sites open and close at different times, so the status above is per site — it can differ from the study's overall status.

  • Christine E Gruessner, M.D. · PRINCIPAL_INVESTIGATOR · National Heart, Lung, and Blood Institute (NHLBI)

Opens a ready-to-send draft in your own email app — review before sending.

  • arrhythmogenic cardiac effects of BTKi and sudden death within the first 12 months of BTKi therapy12 months

    1\. Clinically significant cardiac arrhythmias while on a BTKi (treatment emergent in those without a history of arrhythmias and worsening of arrhythmia for those with an arrhythmia at the time of enrollment testing) within 12 months. For Cohort A, if a patient has an arrhythmia at the time of baseline testing, only worsening or new arrhythmias will be called an event. For Cohort B, all arrhythmias will be called an event. 2. Sudden death