A Phase 3 interventional study of Cilostazol 100 mg in Stroke, sponsored by Northern California Institute of Research and Education. Not yet recruiting at 1 site in Ghana. Open to participants aged 30 Years and older. Per ClinicalTrials.gov, last updated 2026-06-18.
Sponsored by Northern California Institute of Research and Education · Phase 3, Interventional, and Prevention
Global estimates suggest that sub-Saharan Africa (SSA) now has the highest incidence, prevalence, and worst survival outcomes of stroke. With an estimated 1.4 million stroke survivors, outcomes of stroke in SSA are abysmal with 1-month case fatality at 30% and 3-year mortality rate of 84%. Stroke survivors in Africa are at an inordinately high (and worsening) risk of adverse outcomes including recurrent stroke and cardiac events over the medium- to longterm. Given the paucity of resources in the region, testing of therapies, which are potentially highly clinically efficacious and cost-effective, while developing local stroke research capacity and contributing to the global secondary stroke prevention evidence base, is urgently needed. Cilostazol, a phosphodiesterase 3 inhibitor, has shown promising efficacy and safety mainly among an Asian population by cutting risk of major adverse cardiovascular events including stroke, in half, when added to aspirin or clopidogrel (8% vs. 4%, HR 0.52, 95% CI 0.35-0.77), with no increased risk in bleeding or serious adverse events. Cilostazol's potentially strong efficacy, presumed pleiotropic effects, and relatively low cost, make it a highly appealing agent for use in stroke-prone, low-resource settings. Therefore, the overall objective of the CiLostAzol for pReventIon of recurrent sTroke in Africa (CLARITY-AFRICA) study is to deploy a hybrid study design to demonstrate the efficacy and safety of cilostazol twice daily in reducing MACE over 24 months vs. placebo among 1100 recent stroke patients encountered at 12 hospitals in Ghana. Secondly, CLARITY-AFRICA also seeks to develop an implementation strategy for routine integration and policy adoption of cilostazol for post-stroke cardiovascular risk reduction in an under-resourced system. Given its compelling efficacy among a predominantly Asian population, the National Institute of Neurological Disorders and Stroke (NINDS) is poised to fund a US-based clinical trial to assess the longer-term efficacy and safety of cilostazol in a study titled CiLostAzol for pReventIon of recurrent sTroke (CLARITY). The investigators are also aware that European and Australian funding agencies are considering stroke trials of cilostazol. A concurrently executed CLARITYAfrica trial would allow recruitment of a historically underrepresented and high-risk group (Africans), test a therapy that if efficacious could be affordable for broader regional implementation, permit transcontinental mentorship/collaborations, and leverage NINDS impending investment. CLARITY-AFRICA will assess implementation outcomes such as adoption, acceptability, cost, pertinent to uptake of cilostazol in Ghana to inform policy. Regardless of its outcome, findings from CLARITYAFRICA will contribute meaningful information from the African perspective to inform the formulation of guidelines for global adoption of cilostazol into routine care for secondary CVD risk prevention by international bodies such as the World Health Organization. This application will focus on the first 2 aims of CLARITY-AFRICA to conduct the trial and assess secondary outcomes.
8,255 studies on the registry are indexed under Stroke; 2,056 are open to participants now.
This study's planned enrollment of 1,100 is above the median of 49 across 6,024 interventional studies indexed under Stroke.
Browse Stroke studies →Northern California Institute of Research and Education is the lead sponsor of 12 studies on the registry; 4 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.
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.
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.
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.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
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.
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.
A score of how well the liver works in people with liver disease such as cirrhosis: class A is mild, B moderate and C severe.
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
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.
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.
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.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
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.
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.
Child-Pugh class
A score of how well the liver works in people with liver disease such as cirrhosis: class A is mild, B moderate and C severe.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
NYHA class (heart failure)
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Patients allocated to the experimental arm will receive 100mg of cilostazol tablets taken twice daily. To mitigate side-effects in both treatment arms, all patients will begin one tablet daily and titrate to the full dose (one tablet twice daily) after 2 weeks. Participants will stay on the full dose of cilostazol for the remainder of the study.
Drug: Cilostazol 100 mg
Standard of post-stroke care
Patients allocated to the experimental arm will receive 100mg of cilostazol tablets taken twice daily. To mitigate side-effects in both treatment arms, all patients will begin one tablet daily and titrate to the full dose (one tablet twice daily) after 2 weeks. Participants will stay on the full dose of cilostazol for the remainder of the study.
Percent of Participants with Major Adverse Cardiovascular Events
Time frame: 36 months
Percent of Participants with of Major and Minor bleeding
Time frame: 24 months
Percent of Participants with Recurrent stroke (Ischemic or Hemorrhagic)
Time frame: 24 months
Percent of Participants with Cardiovascular Deaths
Time frame: 24 months
Percent of Participants with All Cause Mortality
Time frame: 24 months
Neuro-QoL (Quality of Life)
12 monthly Neuro-QoL uses T-scores, which are standardized scores: Mean (average) = 50 Standard deviation = 10 Interpreting T-scores: Scores 0.5 - 1.0 SD worse than the mean = mild symptoms/impairment Scores 1.0 - 2.0 SD worse than the mean = moderate symptoms/impairment Scores 2.0 SD or more worse than the mean = severe symptoms/impairment For negative domains (e.g. anxiety, depression, fatigue): Higher = Worse We will compare mean Neuro-QoL scores between the two arms of the study at study completion as well as proportions with mild, moderate and severe impairment.
Time frame: 24 months
Exploratory outcomes Montreal Cognitive Assessment
6 monthly. Comparison of Slopes of MOCA scores over 24 months. Range of scores on MOCA: 0 to 30. MOCA screening tool is used to detect mild cognitive impairment and early signs of dementia. It evaluates several cognitive domains, including: Memory Attention Language Visuospatial skills Executive function Orientation A score of 26 or above is considered normal. Scores below 26 may suggest cognitive impairment, depending on education level and clinical context.
Time frame: 24 months
Quality of Life (EQ-5D Questionnaire)
The EQ-5D is a health-related quality of life questionnaire with two parts: Descriptive system: Assesses 5 dimensions-mobility, self-care, usual activities, pain/discomfort, and anxiety/depression-each rated on 3 or 5 levels (from no problems to extreme problems). Visual Analog Scale (VAS): Rates overall health from 0 (worst) to 100 (best). Scoring: The 5-digit health state is converted into a summary index score (range: \<0 to 1), with 1 = full health. The VAS reflects the person's self-rated health. We will compare scores between the two arms at study completion.
Time frame: 24 months
Modified Rankin Score
The Modified Rankin Scale (mRS) measures the degree of disability or dependence in daily activities after a stroke or other neurological injury. Scoring: 0 - No symptoms 1. \- No significant disability; able to carry out all usual activities 2. \- Slight disability; unable to do all previous activities but able to look after own affairs 3. \- Moderate disability; needs some help but can walk unassisted 4. \- Moderately severe disability; unable to walk or attend to bodily needs without help 5. \- Severe disability; bedridden, incontinent, requires constant care 6. \- Dead
Time frame: 24 months
Plan to share: No — Individual participant level data will be aggregated and maintained as de-identified to protect PHI
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This study is not yet recruiting, as verified in Jun 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Cilostazol
Northern California Institute of Research and Education