CATHARSIS
(2015)Objective
Cilostazol plus aspirin versus aspirin alone in preventing progression of intracranial artery stenosis (IAS) and recurrent vascular events.
Study Summary
Intervention
Cilostazol 200 mg/day + aspirin 100 mg/day vs. aspirin 100 mg/day alone. Patients were treated and followed for 2 years.
Study Design
Arms: Array
Outcome
• New silent brain infarcts — 4.8% (CA) vs. 10.0% (A); p=0.24
• Worsening mRS — 10.1% vs. 18.9%; p=0.17
• All vascular events — 3.1% (CA) vs. 7.4% (A); HR 0.39; p=0.09
• Stroke — 2.5% vs. 5.2%; HR 0.44; p=0.19
• Ischemic stroke — 2.5% vs. 4.5%; HR 0.47; p=0.26
• Serious hemorrhage — 4 vs. 3 patients
• No deaths in either group
Bottom Line
Cilostazol 200mg/day + aspirin 100mg/day did not significantly reduce intracranial artery stenosis (IAS) progression vs aspirin alone (9.6% vs 5.6%; P=0.53) over 2 years. However, IAS progression was far lower than expected in both arms (~6-10% vs predicted 35-60%), likely due to aggressive risk factor control. Exploratory analyses showed significant reduction in composite vascular events + silent infarcts (OR 0.37; P=0.04). 163 patients, 60 Japanese centers.
Major Points
- Primary endpoint NS: IAS progression 9.6% (CA) vs 5.6% (A) at 2 years (P=0.53).
- IAS progression far lower than expected (9.6%/5.6% vs predicted 35-60%) — aggressive risk factor control in both arms.
- Vascular events numerically lower: annual rate 3.1% vs 7.4% (HR 0.39; P=0.09, NS).
- Exploratory composites significant: all events + silent infarcts OR 0.37 (P=0.04); + worsening mRS OR 0.41 (P=0.03).
- No deaths in either group. Hemorrhage similar (4 CA vs 3 A).
- Severely underpowered: 163 patients (planned 200+). Events far below projected.
- Baseline imbalances: CA group had more males (77% vs 54%), hypertension (83% vs 69%), diabetes (48% vs 25%) — should bias against CA.
- SBP reduced from 137 to 131 mmHg; total cholesterol from 195 to 183 mg/dL in both arms.
- 163 patients, 60 Japanese centers, open-label, 2-year follow-up.
- Supports larger CSPS.com trial (n=4,000) for definitive evidence on cilostazol in IAS.
Study Design
- Study Type
- Multicenter, open-label, randomized controlled trial
- Randomization
- Yes
- Blinding
- Open-label
- Sample Size
- 165
- Follow-up
- 2 years
- Centers
- 60
- Countries
- Japan
Primary Outcome
Definition: Progression of intracranial artery stenosis at 2 years (on MRA)
| Control | Intervention | HR/OR | P-value |
|---|---|---|---|
| 5.6% | 9.6% | - | 0.53 |
Limitations & Criticisms
- Small sample size reduced power to detect differences
- Open-label design may introduce bias
- Primary endpoint (IAS progression) showed no significant difference
- Lack of event adjudication for stroke subtype
- Shorter than optimal follow-up for chronic disease
Citation
Uchiyama S, et al. Cerebrovasc Dis Extra 2015;5:1–13.