A Phase 3 interventional study of Zastaprazan and Placebo in Ischemic Stroke and Transient Ischemic Attack, sponsored by Asan Medical Center. Not yet recruiting at 15 sites in South Korea. Open to participants aged 19 Years and older. Per ClinicalTrials.gov, last updated 2026-10-09.
Sponsored by Asan Medical Center · Phase 3, Interventional, and Treatment
The goal of this clinical trial is to learn if zastaprazan can help prevent upper gastrointestinal bleeding in adults who have recently had a transient ischemic attack (TIA) or ischemic stroke and are taking antiplatelet or anticoagulant medications. The main question it aims to answer is:
- Does zastaprazan reduce the risk of upper gastrointestinal bleeding compared to placebo in these patients?
Researchers will compare zastaprazan to a placebo (a look-alike tablet that contains no drug) to see if zastaprazan works to prevent upper gastrointestinal bleeding.
Participants will:
2,612 studies on the registry are indexed under Ischemic Stroke; 971 are open to participants now.
This study's planned enrollment of 984 is above the median of 120 across 1,776 interventional studies indexed under Ischemic Stroke.
Browse Ischemic Stroke studies →Asan Medical Center is the lead sponsor of 578 studies on the registry; 73 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Currently initiating or receiving, at the time of randomization, one of the following treatments, with an expected treatment duration of at least 3 weeks:
A. Dual antiplatelet therapy (DAPT) - aspirin in combination with one of the following: clopidogrel, ticagrelor, prasugrel, or cilostazol B. Oral anticoagulant therapy - a NOAC (apixaban, rivaroxaban, dabigatran, or edoxaban) or warfarin
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A “mini-stroke”: temporary stroke-like symptoms caused by reduced blood flow to part of the brain, spinal cord or eye, without signs of a new stroke on a scan.
Stroke symptoms need emergency care at once, even if they go away.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Able to have children. For women this usually means from the first period until menopause, unless permanently unable to through surgery; for men, unless permanently sterile. Read who the line is about — participants, women, men, or their partners.
Criteria about it usually ask for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
TIA (transient ischaemic attack)
A “mini-stroke”: temporary stroke-like symptoms caused by reduced blood flow to part of the brain, spinal cord or eye, without signs of a new stroke on a scan.
Stroke symptoms need emergency care at once, even if they go away.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Life expectancy
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Reproductive potential
Able to have children. For women this usually means from the first period until menopause, unless permanently unable to through surgery; for men, unless permanently sterile. Read who the line is about — participants, women, men, or their partners.
Criteria about it usually ask for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive zastaprazan citrate 20 mg, administered orally once daily (QD) at a fixed dose, in addition to their prescribed antiplatelet therapy (dual antiplatelet therapy) or oral anticoagulant therapy (NOAC or warfarin).
Drug: Zastaprazan
Participants will receive a matching placebo for zastaprazan 20 mg, administered orally once daily (QD) at a fixed dose, in addition to their prescribed antiplatelet therapy (dual antiplatelet therapy) or oral anticoagulant therapy (NOAC or warfarin).
Drug: Placebo
Zastaprazan citrate 20 mg, a potassium-competitive acid blocker (P-CAB), administered orally once daily at a fixed dose, in addition to standard antiplatelet or anticoagulant therapy.
Matching placebo for zastaprazan citrate 20 mg, administered orally once daily at a fixed dose, in addition to standard antiplatelet or anticoagulant therapy.
Time to First Composite Clinical Event of Upper Gastrointestinal Bleeding as Adjudicated by the Clinical Event Committee (CEC)
Time from randomization to the first occurrence of a composite clinical event of upper gastrointestinal (GI) bleeding, as adjudicated by the Clinical Event Committee (CEC). The composite event includes: (1) upper GI bleeding confirmed by endoscopy or imaging, with hematemesis and/or melena; (2) upper GI bleeding of unclear origin, judged by the investigator to originate from the upper GI tract; (3) occult GI bleeding, defined as a decrease in hemoglobin ≥2 g/dL or hematocrit ≥10%; (4) symptomatic uncomplicated gastroduodenal ulcer, confirmed by endoscopy or imaging with persistent pain (≥3 days) and no evidence of bleeding; (5) symptomatic gastroduodenal erosive lesions, with persistent pain (≥3 days) and ≥5 gastroduodenal erosions confirmed by endoscopy, excluding mucosal bleeding; (6) upper GI obstruction; and (7) upper GI perforation.
Time frame: From randomization up to end of study (up to approximately 3 years, including a 24-month enrollment period and 12-month follow-up)
Time to First Composite Clinical Event of Upper Gastrointestinal Bleeding as Judged by the Investigator
Time frame: From randomization up to end of study (up to approximately 3 years)
Time to First Upper Gastrointestinal Bleeding Event Confirmed by Endoscopy or Imaging, as Adjudicated by the Clinical Event Committee (CEC)
Time frame: From randomization up to end of study (up to approximately 3 years)
Time to First Upper Gastrointestinal Bleeding Event of Unclear Origin, as Adjudicated by the Clinical Event Committee (CEC)
Time frame: From randomization up to end of study (up to approximately 3 years)
Time to First Occult Gastrointestinal Bleeding Event, as Adjudicated by the Clinical Event Committee (CEC)
Time frame: From randomization up to end of study (up to approximately 3 years)
Time to First Symptomatic Uncomplicated Gastroduodenal Ulcer Event, as Adjudicated by the Clinical Event Committee (CEC)
Time frame: From randomization up to end of study (up to approximately 3 years)
Time to First Symptomatic Gastrointestinal Erosive Lesion Event, as Adjudicated by the Clinical Event Committee (CEC)
Time frame: From randomization up to end of study (up to approximately 3 years)
Time to First Upper Gastrointestinal Obstruction Event, as Adjudicated by the Clinical Event Committee (CEC)
Time frame: From randomization up to end of study (up to approximately 3 years)
Time to First Upper Gastrointestinal Perforation Event, as Adjudicated by the Clinical Event Committee (CEC)
Time frame: From randomization up to end of study (up to approximately 3 years)
Time to First All Gastrointestinal Bleeding Event (Upper and Lower), Including International Society on Thrombosis and Haemostasis (ISTH) Major Bleeding or clinically relevant non-major bleeding (CRNMB)
Time frame: From randomization up to end of study (up to approximately 3 years)
Time to First Lower Gastrointestinal Bleeding Event
Time frame: From randomization up to end of study (up to approximately 3 years)
Time to First Non-Gastrointestinal ISTH Major Bleeding or CRNMB Event
Time frame: From randomization up to end of study (up to approximately 3 years)
Time to First Clinically Significant Non-Bleeding Upper Gastrointestinal Event
Time frame: From randomization up to end of study (up to approximately 3 years)
Time to First Hemoglobin-Related Event
Time frame: From randomization up to end of study (up to approximately 3 years)
Time to First Cerebrovascular or Cardiovascular Event
Time from randomization to the first occurrence of a cerebrovascular or cardiovascular event, including ischemic stroke, transient ischemic attack, systemic embolism, myocardial infarction, or vascular death.
Time frame: From randomization up to end of study (up to approximately 3 years)
All-Cause Mortality
Time frame: From randomization up to end of study (up to approximately 3 years)
Subgroup Analyses of the Primary Composite Upper Gastrointestinal Bleeding Event
Exploratory subgroup analyses of the primary efficacy outcome (time to first composite clinical event of upper GI bleeding), performed across the following pre-specified subgroups: (1) timing of zastaprazan initiation relative to onset of ischemic stroke/TIA (acute phase, within 4 weeks vs. subacute phase, after 4 weeks); (2) history of prior gastrointestinal bleeding (yes vs. no); (3) concomitant treatment type (dual antiplatelet therapy vs. anticoagulant therapy); (4) age (\<65 years vs. ≥65 years); (5) baseline renal function (eGFR ≥60 mL/min/1.73m² vs. \<60 mL/min/1.73m²); and (6) stroke mechanism.
Time frame: From randomization up to end of study (up to approximately 3 years)
Plan to share: No
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Studies of the drug tested here: Zastaprazan