The HALT Biomarker Study (HALT)
![]() |
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. |
ClinicalTrials.gov Identifier: NCT04552275 |
Recruitment Status :
Recruiting
First Posted : September 17, 2020
Last Update Posted : November 10, 2021
|
- Study Details
- Tabular View
- No Results Posted
- Disclaimer
- How to Read a Study Record
The purpose of the HALT Biomarkers study are to identify a panel of circulating proteins that discriminates between patients with and without Hypo-Attenuated Leaflet Thickening (HALT) and can be used to supplement the diagnosis of HALT; to characterize changes in circulating proteins after treatment of HALT with systemic anticoagulation; and to identify circulating proteins that predict the occurrence of HALT.
The study population will be adult patients undergoing transfemoral transcatheter aortic valve replacement (TAVR) for severe aortic stenosis (AS) or bioprosthetic valve degeneration. Enrollment will continue until 30 patients with HALT are identified for completion of phase 1. Based on a HALT incidence rate of 10%, we anticipate enrolling 300 patients.
Patients are enrolled prior to undergoing transfemoral TAVR. Blood samples, clinical data and echocardiograms will be collected at the following timepoints: baseline (pre-TAVR, T0), post-TAVR (pre-discharge, T1), 30-day follow-up (window 3-9 weeks, T2), and 6-month follow-up (T3). Cardiac 4D CT will be performed at the 30-day follow-up visit to screen for the occurrence of HALT.
Patients with HALT will be treated with systemic anticoagulation for 5-6 months, at which point a follow-up CT scan and blood sample will be obtained. Control subjects will also undergo a 6-month study visit with blood sample collection. The study will be conducted within two phases. Phase 1 will serve as a derivation / discovery study in which candidate protein biomarkers of HALT will be identified.
Once this is successfully completed, a second cohort will be enrolled within phase 2. Phase 2 will be performed under the auspices a future contract or amendment and will seek to cross-validate the initial study findings.
Condition or disease | Intervention/treatment | Phase |
---|---|---|
Aortic Stenosis Hypo-attenuated Leaflet Thickening Bioprosthetic Valve Degeneration | Diagnostic Test: Proteomics Analysis | Phase 1 |
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 300 participants |
Allocation: | Non-Randomized |
Intervention Model: | Parallel Assignment |
Masking: | None (Open Label) |
Primary Purpose: | Diagnostic |
Official Title: | Circulating Biomarkers of Hypo-Attenuated Leaflet Thickening After Transcatheter Aortic Valve Replacement |
Actual Study Start Date : | June 22, 2020 |
Estimated Primary Completion Date : | June 22, 2030 |
Estimated Study Completion Date : | June 22, 2035 |

Arm | Intervention/treatment |
---|---|
HALT Cohort
Patients who develop HALT
|
Diagnostic Test: Proteomics Analysis
Determine a panel of circulating proteins that discriminates between patients with and without Hypo-Attenuated Leaflet Thickening (HALT) |
Control Group
Patients who do not develop HALT
|
Diagnostic Test: Proteomics Analysis
Determine a panel of circulating proteins that discriminates between patients with and without Hypo-Attenuated Leaflet Thickening (HALT) |
- Derivation of the panel of circulating proteins indicative of HALT [ Time Frame: 6 months ]1. Establish the incidence of similar proteomic profiles and the rate to which the profile occurs in TAVR recipients with HALT via a high-throughput precision proteomics platform which utilizes the proximity extension assay (PEA). PEA merges a dual-recognition antibody-based immunoassay with quantitative real-time PCR that allows for the simultaneous quantification of 92 proteins. We will focus on the 5 highest yield panels for the current investigation: cardiovascular II, cardiovascular III, cardiometabolic, inflammation, and oncology II panels. These panels will allow for the assessment of 460 circulating proteins.
- Establish the rate at which these characteristics indicative of future HALT [ Time Frame: 6 months ]Using data analysis of baseline patient characteristics to establish the rate that they are indicative of future HALT in patients with aortic stenosis. The sampling frame assumes the sequencing of 460 proteins; a 5% False Discovery Rate; a 10% prognostic prevalence; a minimum fold change of 2; and a normalization ratio of 1.
- Cross-validation of the panel of circulating proteins indicative of HALT [ Time Frame: 6 months ]3. Using 20 matched pairs of subjects with and without HALT, the derivation of the HALT indicative panel of circulating proteins gathered through PEA will be cross-validated using data analysis to establish the rate to which the panel is present in both cohorts. This rate will be used to determine if the proteomic profile of a patient can be used as a diagnostic test for the presence of HALT.

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | 65 Years and older (Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Age > 65 years
- Subject with severe native AS or severe bioprosthetic valve degeneration
- Subject undergoing transfemoral TAVR using a Medtronic Evolut R, Evolut Pro or Evolut Pro+ transcatheter heart valve
Exclusion Criteria:
- Chronic anticoagulation therapy
- Contraindication to systemic oral anticoagulation therapy
- Chronic kidney disease with EGFR<30 ml/min
- Bleeding diathesis or known coagulopathy
- Hypercoagulable state
- Life-expectancy <12 months due to other medical conditions (e.g., malignancy, severe Alzheimer's disease, etc.)
- The patient is currently participating in another investigational device or drug study that has not reached its primary objective/endpoint
- Pregnant, lactating, or planning pregnancy within next 12 months

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04552275
Contact: Roukoz Abou Karam | raboukaram@mgh.harvard.edu | ||
Contact: Paris J Jamiel, BS | (617) 726-0996 | pjamiel@mgh.harvard.edu |
United States, Massachusetts | |
Massachusetts General Hospital | Recruiting |
Boston, Massachusetts, United States, 02114 | |
Contact SELMARIAH@mgh.harvard.edu | |
Principal Investigator: Sammy Elmariah, MD | |
United States, Minnesota | |
Minneapolis Heart Institute | Not yet recruiting |
Minneapolis, Minnesota, United States, 55407 | |
Contact Santiago.Garcia@allina.com | |
Principal Investigator: Santiago Garcia, MD | |
United States, New Hampshire | |
Catholic Medical Center | Recruiting |
Manchester, New Hampshire, United States, 03103 | |
Contact fahad.gilani@cmc-nh.org | |
Principal Investigator: Fahad S Gilani |
Responsible Party: | Sammy Elmariah, Director, Interventional Cardiology Research, Massachusetts General Hospital |
ClinicalTrials.gov Identifier: | NCT04552275 |
Other Study ID Numbers: |
2020P001793 |
First Posted: | September 17, 2020 Key Record Dates |
Last Update Posted: | November 10, 2021 |
Last Verified: | November 2021 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | No |
Studies a U.S. FDA-regulated Device Product: | No |
Aortic Valve Stenosis Aortic Valve Disease Heart Valve Diseases |
Heart Diseases Cardiovascular Diseases Ventricular Outflow Obstruction |