Objective:

To estimate the plausible effects of albumin, cilostazol, and combination therapy on reducing delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (aSAH).

Approach:

• Treatment Classes: Defined four treatment classes: control, albumin-only, cilostazol-only, and combination therapy.
• Primary Endpoint: National Institute of Neurological Disorders and Stroke Common Data Elements-defined DCI (CDE-d-DCI) on CT on days 10 to 14.
• Simulation Model: Used a prior-predictive Monte Carlo model based on historical data to estimate treatment effects.

Key Findings:

• Median absolute risk reductions (ARRs) versus control were 9.1 percentage points for albumin (90% simulation interval, −3.3 to 18.1; prior-predictive probability of ARR > 0, 89.8%), 18.1 percentage points for cilostazol (11.0 to 25.4; 99.9%), and 21.7 percentage points for combination therapy (12.4 to 29.9; 99.8%).
• The incremental benefit of adding albumin to cilostazol was small and uncertain at 3.5 percentage points (−3.0 to 8.9).
• The additive interaction effect was also uncertain, showing a potential reduction of 5.5 percentage points (−11.9 to 2.8).

Interpretation:

The simulations provide planning-level projections and do not establish efficacy.

Limitations:

• The study does not analyze observed outcomes.
• Estimates are conditional on specified priors and model structure.

Conclusion:

The findings support the need for further randomized controlled trials to evaluate the effects of cilostazol and albumin.