Immunomodulatory Effects of PCSK9 Inhibition (INSPIRAR)

September 23, 2025 updated by: Mabel Toribio, Massachusetts General Hospital

ImmuNomodulatory EffectS of PCSK9 Inhibition: A TaRgeted Molecular Imaging AppRoach

Cardiovascular disease (CVD) represents the leading cause of death worldwide. While medications, such as statins, significantly reduce atherosclerotic CVD (ASCVD) risk by lowering low density lipoprotein levels, they may also have pleiotropic effects on inflammation. The immunomodulatory effects of these medications are relevant to ASCVD risk reduction given that inflammation plays a central role in atherosclerotic plaque formation (atherogenesis) and influences the development of vulnerable plaque morphology. Patients on statins, however, may have residual inflammation contributing to incident ASCVD despite the potent LDL-lowering effects of statins. While new therapies, such as proprotein convertase subtilisin/kexin type 9 (PSCK9) inhibitors, further reduce incident ASCVD and drastically reduce LDL-C below that achieved by statin therapy alone, PCSK9 inhibitors may also have pleiotropic effects on inflammation. Thus, PCSK9 inhibitors may help reduce arterial inflammation to a level closer to that of patients without ASCVD. This study will apply a novel targeted molecular imaging approach, technetium 99m (99mTc)-tilmanocept SPECT/CT, to determine if residual macrophage-specific arterial inflammation is present with statin therapy and the immunomodulatory effects of PSCK9 inhibition. Given the continued high mortality and morbidity attributable to ASCVD, strong imperatives exist to better understand the immunomodulatory effects of lipid lowering therapies and residual inflammatory risk. This understanding, in turn, will inform the development of new ASCVD preventative and treatment strategies as well as elucidate other indications for established therapies.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Withdrawn

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Observational

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Locations

  • United States
    • Massachusetts
      • Boston, Massachusetts, United States, 02114
        • Massachusetts General Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years to 85 years (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Sampling Method

Probability Sample

Study Population

Case: People with known ASCVD, on high-intensity statin therapy for at least 6 months and about to initiate PCSK9 inhibitor therapy

Control: Healthy controls with no known ASCVD and not on statin

Description

Inclusion Criteria:

  • 18 to 85 years of age
  • CASE PARTICIPANTS ONLY: History of ASCVD (including a history of coronary artery disease, carotid artery disease, peripheral artery disease, acute coronary syndrome, percutaneous coronary intervention, coronary bypass surgery, carotid endarterectomy, stroke or TIA)
  • CASE PARTICIPANTS ONLY: High-intensity statin therapy for at least 6 months prior enrollment and without an interruption of >1 month
  • CASE PARTICIPANTS ONLY: Initiation of PCSK9 inhibition with either evolocumab or alirocumab (and not inclisiran - PSCK9 inhibition through small interfering RNA)

Exclusion Criteria:

  • pregnancy or breastfeeding
  • CONTROL PARTICIPANTS ONLY: No known history of ASCVD (including a history of coronary artery disease, carotid artery disease, peripheral artery disease, acute coronary syndrome, percutaneous coronary intervention, coronary bypass surgery, carotid endarterectomy, stroke or TIA)
  • current treatment with prescription, systemic (oral, IV, IM or intra-articular) steroids or anti-inflammatory/immune suppressant medical therapies (excluding topical therapies, UV therapy, ASA-derivative therapies, or NSAIDS) for autoimmune/inflammatory diseases (psoriasis, RA, IBD, lupus), post-transplant care, asthma, or pain syndromes
  • use of oral steroids or prescription oral anti-inflammatory/immune suppressant medication for > 7 days within the past 1 month
  • use of IV, IM or intra-articular steroids or IV, IM or intra-articular anti-inflammatory/immune suppressant medication within the past 3 months
  • Any prior use of PCSK9 inhibitors including both monoclonal antibodies or small interfering RNA
  • CONTROL PARTICIPANTS ONLY: use of cholesterol lowering therapy (including statins, ezetimibe, bempedoic acid, PCSK9 inhibitors including both monoclonal antibodies or small interfering RNA, niacin, fibrates) or other lipid lowering agents associated with ASCVD risk reduction such as Vascepa. Cholesterol lowering therapies that that predominantly target triglycerides including over the counter omega-3 fatty acids and Lovaza are permitted.
  • known allergy to dextrans and/or DTPA and/or radiometals
  • significant radiation exposure (>2 CT angiograms) received within the past 12 months
  • concurrent enrollment in another research study judged by the study investigators to interfere with the current study

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort

Group / Cohort

A group or subgroup of participants in an observational study that is assessed for biomedical or health outcomes.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Case group: History of ASCVD, on high-intensity statins and initiating PCSK9 inhibitor therapy
History of ASCVD, on high-intensity statins and initiating PCSK9 inhibitor therapy
Other: 99mTc-tilmanocept SPECT/CT scanning
99mTc-Tilmanocept SPECT/CT allows for visualization of macrophage-specific arterial infiltration
Control group: No history of ASCVD, not on statins or initiating PCSK9 inhibitor therapy
No history of ASCVD, not currently on high-intensity statins, other lipid lowering therapy or initiating PCSK9 inhibitor therapy
Other: 99mTc-tilmanocept SPECT/CT scanning
99mTc-Tilmanocept SPECT/CT allows for visualization of macrophage-specific arterial infiltration

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Time Frame
Change in the percent volume with aortic 99mTc-tilmanocept uptake across different uptake thresholds after PCSK9 inhibitor therapy for 12 months (case participants only)
Time Frame: Baseline and 12 Months
Baseline and 12 Months
Between-group difference (case participants versus control participants) in percent volume with aortic 99mTc-tilmanocept uptake across different uptake thresholds
Time Frame: Baseline
Baseline

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Time Frame
Relationship between baseline immune cell subpopulations (cells/µL) and aortic volume with 99mTc-tilmanocept uptake
Time Frame: Baseline and 12 Months
Baseline and 12 Months
Relationship between baseline markers of immune activation/ systemic inflammation and aortic volume with 99mTc-tilmanocept uptake
Time Frame: Baseline and 12 Months
Baseline and 12 Months
Relationship between change in macrophage-specific arterial infiltration with PCSK9 inhibitors and change in immune cell subpopulations (cells/µL)
Time Frame: Baseline and 12 Months
Baseline and 12 Months
Relationship between change in macrophage-specific arterial infiltration with PCSK9 inhibitors and change in markers of immune activation/ systemic inflammation
Time Frame: Baseline and 12 Months
Baseline and 12 Months
Relationship between change in macrophage-specific arterial infiltration with PCSK9 inhibitors and baseline immune cell subpopulations (cells/µL)
Time Frame: Baseline and 12 Months
Baseline and 12 Months
Relationship between change in macrophage-specific arterial infiltration with PCSK9 inhibitors and baseline markers of immune activation/ systemic inflammation
Time Frame: Baseline and 12 Months
Baseline and 12 Months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Massachusetts General Hospital

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
April 4, 2024

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
March 1, 2026

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
March 1, 2026

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
January 20, 2023

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 30, 2023

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
February 9, 2023

Study Record Updates

Last Update Posted (Estimated)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
September 26, 2025

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
September 23, 2025

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
September 1, 2025

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 2022P002214

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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