ClinicalTrials.gg
Not yet recruitingNCT06919835CLARITY-AfricaUpdated Jun 18, 2026

CiLostAzol for pReventIon of Recurrent sTroke in Africa

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

Phase
Phase 3
Study type
Interventional
Enrollment
1,100
Allocation
Randomized
Ages
30 Years and older
Sex
All
01

Study summary

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.

02

Conditions studied

  • Stroke

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Keywords

  • Stroke
  • Africa
  • post-stroke
03

In context

Stroke

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 →

Lead sponsor

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.

04

Who can participate

Ages eligible
30 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

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.

Inclusion criteria

  1. Above the age of 30 years; male or female (sex is a biological variable of interest)
  2. Ischemic stroke or high-risk (ABCD2 score >= 6) diagnosis no greater than six months before enrollment. Ischemic strokes including lacunar, large vessel atherosclerotic, embolic stroke of undetermined source subtypes are eligible (Ischemic stroke or TIA should be confirmed by either with a cranial CT or MRI within 10 days of symptom onset)
  3. Aspirin or clopidogrel monotherapy
  4. Subjects with stroke may present with two or more of the following additional conditions: age ≥65 years, documented diabetes mellitus or previous treatment with oral hypoglycemic or insulin; documented hypertension >140/90mmHg or previous treatment with anti-hypertensive medications; Mild to moderate renal dysfunction ( 60-30ml/min/1.73m2); Prior myocardial infarction
  5. Legally competent to sign or have a LARs who is able to provide consent for them
  6. In the opinion of the treating physician, patient is medically stable, capable of participating in a randomized trial, and willing and able to attend follow-up.
  7. Able to do labs at all study intervals (7 visits total)

Exclusion criteria

Exclusion Criteria:

  1. Unable to provide a valid
  2. to cilostazol (namely (i) , (ii) active pathologic bleeding, e.g. bleeding peptic ulcer, intracranial bleeding due to reversible aggregation, (iii) congestive cardiac failure.)
  3. Hemorrhagic stroke survivor within the last 2 years
  4. Use of an anticoagulant medication or indication for use of an anticoagulant (e.g. atrial fibrillation)
  5. On dual antiplatelet therapy (patients are eligible after completion of a course of dual antiplatelet therapy)
  6. Modified Rankin Scale 5
  7. Thrombocytopenia (platelet count \<1000,000)
  8. Severe liver dysfunction (active hepatitis or hepatic insufficiency with score B or C)
  9. Congestive heart failure, defined as Class III or above (marked limitation of physical activity)
  10. Nursing/pregnant mothers
Terms in these criteria, in plain language(8)

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.

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.

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.

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.

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.

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.

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.

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.

NYHA class (heart failure)

The New York Heart Association’s four classes of how much heart failure limits physical activity.

I
No limits: ordinary activity causes no undue tiredness or breathlessness.
II
Slight limits: comfortable at rest, ordinary activity causes symptoms.
III
Marked limits: comfortable at rest, less than ordinary activity causes symptoms.
IV
Symptoms even at rest; any activity makes them worse.

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.

05

Study design

Phase
Phase 3
Primary purpose
Prevention
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Triple (Participant, Care provider, Investigator)
Enrollment
1,100 participants (estimated)

Study arms

  • Experimental
    Cilostazol Experimental Arm

    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

  • No intervention
    Control Arm

    Standard of post-stroke care

Interventions

  • 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.

06

What researchers measure

Primary outcomes

  1. Percent of Participants with Major Adverse Cardiovascular Events

    Time frame: 36 months

Secondary outcomes

  1. Percent of Participants with of Major and Minor bleeding

    Time frame: 24 months

  2. Percent of Participants with Recurrent stroke (Ischemic or Hemorrhagic)

    Time frame: 24 months

  3. Percent of Participants with Cardiovascular Deaths

    Time frame: 24 months

  4. Percent of Participants with All Cause Mortality

    Time frame: 24 months

  5. 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

  6. 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

  7. 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

  8. 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

07

Study locations

1 site
08

References and documents

Individual participant data

Plan to share: No — Individual participant level data will be aggregated and maintained as de-identified to protect PHI

No publications or documents are linked to this record.

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Jun 18, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT06919835
Lead sponsor
Northern California Institute of Research and Education
Responsible party
Bruce Ovbiagele (Chief of Staff, Northern California Institute of Research and Education) — Principal investigator
First posted
Apr 9, 2025
Start date
Aug 1, 2026 (estimated)
Primary completion
Jul 31, 2029 (estimated)
Completion
Aug 31, 2029 (estimated)
Last update
Jun 18, 2026

Study contacts

Bruce Ovbiagele, M.D., MSc, MAS, MBA
Contact
bruce.ovbiagele@va.gov
415-750-2047
Raelle Tagge, MPH
Contact
raelle.tagge@ncire.org

Oversight

Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

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

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