Cervene in acute ischemic stroke: Results of a double-blind, placebo-controlled, dose-comparison study

Cervene (nalmefene), an opioid antagonist with relative kappa receptor selectivity, has shown neuroprotective effects in multiple experimental central nervous system injury and ischemic models. The agent already has a well-established safety profile in various clinical indications. Results from an earlier pilot study in 44 acute stroke patients suggest that Cervene administered by 24-hour maintenance infusion was safe and tolerable. The primary and secondary objectives of the current study were to assess the dose-related safety and preliminary efficacy of Cervene in patients with acute ischemic stroke. Methods: The present investigation was a Phase II, placebocontrolled, double-blind, randomized, dose-comparison, parallel-group study of a 24-hour administration of Cervene injection. Patients with acute ischemic stroke, onset of symptoms within 6 hours, and baseline score ≥4 on the National Institute of Health Stroke Scale (NIHSS) were randomized to 1 of 4 treatment groups: Cervene 6 mg, 20 mg, 60 mg or placebo. The primary efficacy outcome was the proportion of patients achieving a score of ≥60 on the Barthel Index and a rating of "moderate disability" or better on the Glasgow Outcome Scale at 12 weeks. Results: A total of 312 patients were randomized at 28 centers. All doses of Cervene were well tolerated. Overall, there was no significant difference in 3-month functional outcome for any dose of Cervene treatment compared with placebo. However, a prospective secondary analysis showed that both male and female patients less than age 70 years may have had an improved 3-month outcome. Conclusions: The results of this study indicate that the competitive kappa receptor opiate antagonist Cervene can be given safely to acute stroke patients at doses up to 60 mg/24 hr. Although overall there was no significant difference in the 3-month outcome, Cervene treatment may be associated with improved outcomes for patients younger than age 70.