The Neuroprotection with Statin Therapy for Acute Recovery Trial (NeuSTART): an adaptive design phase I dose-escalation study of high-dose lovastatin in acute ischemic stroke

摘要

There is growing experimental and clinical evidence that by reducing downstream products of the mevalonate pathway other than cholesterol, HMG-CoA reductase inhibitors (‘statins’) have beneficial effects on endothelial function, coronary and cerebral blood flow, inflammation, and hemostasis. Statins have been shown in rodent models of acute ischemic stroke to reduce neuronal injury and infarct size in a dose-dependent fashion. The objective of this early phase trial will be to determine the maximal-tolerated dose of lovastatin for short-term acute stroke therapy. In this multicenter phase 1B dose-escalation and dose-finding study, 33 patients with acute ischemic stroke will be administered lovastatin in increasing doses from one to 10 mg/kg daily for 3 days beginning within 24 hours after symptom onset. The primary safety outcomewill be occurrence of myotoxicity or hepatotoxicity, defined by clinical and laboratory criteria, and the study is designed to determine the highest dose of lovastatin that can be administered with <10% risk of myotoxicity or hepatotoxicity. The statistical design of the study utilizes an adaptive design, the Continual Reassessment Method, which is novel to stroke trials, to find the optimal dosage. The dose–toxicity model is calibrated such that the method will eventually select a dose that causes 7–13% dose-limiting toxicity (within 3% of target). A sample size of 33 will ensure that estimates of any binary variables will have a 95% confidence interval of width ≤0·34, and enable us to detect any unexpected toxicity that occurs at 5% rate (in a non-dose-dependent fashion) with probability 0·82. The probability of choosing a dose for further trials with 25% or higher likelihood of toxicity is no more than 23%. The presently described trial represents a new approach for treatment of acute ischemic stroke, as well as a novel way of conducting a phase I trial, evaluating safety and determining an optimal dose of a potential neuroprotectant drug.