A Research Study to Look at the Effect of Ziltivekimab on Plaque in the Blood Vessels of the Heart, Compared to Placebo, in People With a Heart Attack
ZEPHYR
Effects of Ziltivekimab Versus Placebo on Coronary Atherosclerosis in Patients With Acute Myocardial Infarction. A Serial, Multivessel, Intravascular Ultrasound, Near-infrared Spectroscopy and Optical Coherence Tomography Imaging Study
2 other identifiers
interventional
332
6 countries
20
Brief Summary
The study is testing the effect of ziltivekimab on reducing plaque in the blood vessels of the heart, specifically aiming to manage or reduce atherosclerotic plaque. The purpose of the study is to determine whether ziltivekimab can effectively reduce this plaque. Participants will either receive ziltivekimab (the active medicine) or a placebo (a dummy medicine with no effect on the body), with the treatment assignment decided by chance. It is important to note that ziltivekimab is not yet approved in any country or region worldwide; therefore, it is a new medicine that doctors cannot prescribe. The study will last for about 15 months.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P50-P75 for phase_3
Started Dec 2025
Typical duration for phase_3
20 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
November 27, 2025
CompletedStudy Start
First participant enrolled
December 18, 2025
CompletedFirst Posted
Study publicly available on registry
December 24, 2025
CompletedPrimary Completion
Last participant's last visit for primary outcome
November 14, 2028
ExpectedStudy Completion
Last participant's last visit for all outcomes
February 24, 2029
March 11, 2026
March 1, 2026
2.9 years
November 27, 2025
March 10, 2026
Conditions
Outcome Measures
Primary Outcomes (1)
Change in percent atheroma volume (PAV) as determined by greyscale intravascular ultrasound (IVUS) in matched regions of interest
Percentage (%).
From randomisation (week 0) to end-of-study (52-week)
Secondary Outcomes (17)
Change in maximum lipid core burden index (LCBI) in any 4-mm segment(maxLCBI4mm) as determined by Near-infrared spectroscopy (NIRS) in matched regions of interest
From randomisation (week 0) to end-of-study (52-week)
Change in minimal fibrous cap thickness as determined by (optical coherence tomography) OCT in matched regions of interest
From randomisation (week 0) to end-of-study (52-week)
Change in lipid core burden index (LCBI) total as determined by NIRS in matched regions of interest
From randomisation (week 0) to end-of-study (52-week)
Change in average angular extension (AAE) of macrophages as determined by OCT in matched regions of interest
From randomisation (week 0) to end-of-study (52-week)
Change in normalized total atheroma volume (NTAV) by IVUS in matched regions of interest
From randomisation (week 0) to end-of-study (52-week)
- +12 more secondary outcomes
Study Arms (2)
Ziltivekimab dose level 1 + standard of care (SOC)
EXPERIMENTALParticipants receive dose level 1 of ziltivekimab along with standard of care (SOC) subcutaneously once monthly for 12 months.
Placebo + SOC
PLACEBO COMPARATORParticipants receive a placebo along with standard of care (SOC) subcutaneously once monthly for 12 months.
Interventions
Participants will receive ziltivekimab subcutaneously.
Participants will receive placebo matched to ziltivekimab subcutaneously.
Eligibility Criteria
You may qualify if:
- Informed consent obtained before any study-related activities. Study-related activities are any procedures that are carried out as part of the study, including activities to determine suitability for the study.
- Age 18 years or above at the time of providing informed consent.
- Acute myocardial infarction, with at least one coronary segment (culprit lesion) treated with percutaneous coronary intervention (PCI):
- a. Acute ST-segment elevation myocardial infarction (STEMI) with all of the following: i. Onset of relevant pain suggestive of cardiac ischemia within less than or equal to (=\<) 24h of index angiography.
- ii. Electrocardiogram (ECG)-changes (in the absence of left ventricular hypertrophy or left bundle branch block): ST-segment elevation at the J point in at least two contiguous leads greater than or equal to (\>=) 0.25 millivolts (mV) in men less than (\<) 40 years, \>=0.2 mV in men \>=40 years, or \>=0.15 mV in women in leads V2-V3; and/or \>=0.1 mV in all other leads.
- Non-ST segment elevation myocardial infarction (NSTEMI), with rise and/or fall in cardiac troponin I or T with at least one value above the 99th percentile upper reference limit.
- At least two major native coronary arteries ‡ ("study vessels") each meeting the following criteria for intracoronary imaging immediately following the qualifying PCI procedure:
- Angiographic evidence of a reduction in lumen diameter between \>20 and \<50 percent (%) by angiographic visual estimation.
- Study vessel deemed to be accessible to imaging catheters and suitable for intracoronary imaging in the proximal (50 millimeter \[mm\]) segment ("study segment").
- Study vessel may not be a bypass (saphenous vein or arterial) graft or a bypassed native vessel.
- Study vessel must not have undergone previous PCI within the study segment.
- A vessel which is candidate for intervention at the time of qualifying PCI or over the following 6 months in the judgment of the Investigator, cannot be a study vessel.
- \. Hemodynamic stability (as assessed by the treating physician) allowing the repetitive administration of nitroglycerine during the study specific imaging procedure.
- \. Ability to understand the requirements of the study and to provide informed consent 7. Willingness to undergo follow-up intracoronary imaging. 8. Possibility for randomisation and administration of the loading dose as early as possible after invasive procedure and latest within 48 hours after index PCI.
- Two study segments may be obtained in the same vessel (e.g. two study segments in the Right Coronary Artery \[RCA\] or Left Circumflex Artery \[LCX\]), at the investigators discretion, considering vessel anatomy (e.g. left or right dominance), and where suitable landmarks between segments are at least 40 mm apart and with vessel wall irregularities.
You may not qualify if:
- Known or suspected hypersensitivity to study intervention(s) or related products.
- Known allergy to contrast medium, heparin, aspirin, ticagrelor or prasugrel.
- Previous participation in this study. Participation is defined as randomisation.
- Female of childbearing potential.
- Any condition, which in the investigator's opinion might jeopardise participant's safety or compliance with the protocol.
- Left-main disease, defined as \>=50 percent (%) reduction in lumen diameter of the left main coronary artery by angiographic visual estimation
- Three-vessel disease, defined as the presence of severe or significant coronary artery disease (CAD) on the basis of angiography, imaging, or physiology, in all three major epicardial territories (including major branches) that have an indication for revascularization or are too advanced to be treated.
- History of coronary artery bypass surgery
- Thrombolysis In Myocardial Infarction (TIMI) flow \<2 of the infarct-related artery after PCI
- Unstable clinical status (hemodynamic or electrical instability. Hemodynamic instability defined as any of the following:
- Killip Class III or IV. Sustained and/or symptomatic hypotension (as assessed by the treating physician).
- Significant coronary calcification or tortuosity deemed to preclude Intra-Vascular Ultrasound (IVUS), Near Infrared Spectroscopy (NIRS) and Optical Coherence Tomography (OCT) evaluation.
- Uncontrolled cardiac arrhythmia, defined as recurrent and symptomatic ventricular tachycardia or atrial fibrillation with rapid ventricular response not controlled by medications in the past 3 months prior to screening.
- Severe kidney impairment defined as any of the following:
- Previous or current estimated glomerular filtration rate \<30 milliliters per minute (ml/min) /1.73 square meter (m\^2) Chronic haemodialysis or peritoneal dialysis.
- +20 more criteria
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Novo Nordisk A/Slead
Study Sites (20)
Medizinische Universität Wien
Vienna, 1090, Austria
Aalborg Universitetshospital Hjertemedicinsk Afdeling
Gistrup, 9260, Denmark
Rigshospitalet - Kardiologisk Forskningsenhed
København Ø, 2100, Denmark
Azienda Ospedaliera San Giovanni Addolorata
Rome, Lazio, 00184, Italy
Azienda Socio Sanitaria Territoriale Papa Giovanni XXIII
Bergamo, Lombardy, 24127, Italy
DAI Scienze Mediche - UOC Endocrinologia
Messina, Sicily, 98124, Italy
Presidio Ospedaliero di Rivoli
Rivoli, To, 10098, Italy
Ospedale Policlinico San Martino
Genova, 16132, Italy
AOU Maggiore della Carità di Novara - Dipartimento Toraco-Cardio-Vascolare - SCDU Cardiologia
Novara, 28100, Italy
Azienda Ospedaliera Universitaria San Luigi Gonzaga - S.C.D.O. Microcitemie e malattie rare ematologiche
Orbassano, 10043, Italy
Fondazione Policlinico Universitario Agostino Gemelli IRCS
Rome, 00168, Italy
IRCCS Policlinico San Donato
San Donato Milanese, 20097, Italy
Radboudumc
Nijmegen, 6525 GA, Netherlands
Erasmus MC
Rotterdam, 3015 GD, Netherlands
Hospital Universitario de la Princesa
Madrid, 28006, Spain
Hospital Universitario Marqués de Valdecilla
Santander, 39008, Spain
Universitäres Herzzentrum
Basel, 4031, Switzerland
Inselspital-Universitätsklinik für Kardiologie
Bern, 3010, Switzerland
HUG-Service de Cardiologie
Geneva, 1205, Switzerland
LUKS-Herzzentrum
Lucerne, 6000, Switzerland
MeSH Terms
Conditions
Interventions
Condition Hierarchy (Ancestors)
Study Officials
- STUDY DIRECTOR
Clinical Transparency (dept. 2834)
Novo Nordisk A/S
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- phase 3
- Allocation
- RANDOMIZED
- Masking
- QUADRUPLE
- Who Masked
- PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
- Masking Details
- Sponsor staff involved in the clinical trial is masked according to company standard procedures.
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- INDUSTRY
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
November 27, 2025
First Posted
December 24, 2025
Study Start
December 18, 2025
Primary Completion (Estimated)
November 14, 2028
Study Completion (Estimated)
February 24, 2029
Last Updated
March 11, 2026
Record last verified: 2026-03
Data Sharing
- IPD Sharing
- Will share
According to the Novo Nordisk disclosure commitment on novonordisk-trials.com.