ASP-II: Ancrod Stroke Program: Ancrod (Viprinex™) for the Treatment of Acute, Ischemic Stroke


Phase 3 Results N/A

Trial Description

The primary purpose of this study is to determine whether a brief intravenous infusion of ancrod started within 6 hours of stroke onset improves functional outcome at 3 months.

Detailed Description

With prior approval by the FDA, an interim analysis for futility was performed when 500 subjects had been entered into the two parallel trials, NCT00141001 and NCT00300196. The analyses were reviewed by the data safety monitoring board, which recommended that both studies be terminated because of futility. This was done at a point where 650 subjects had been entered into both studies, combined, but analyses were conducted only on the initial 500 subjects. Results of the abbreviated analysis will be found with study NCT00141001 since that study contributed most of the subjects to the analysis.

Trial Stopped: Futility



  • Ancrod (Viprinex®)Drug
    Intervention Desc: Fibrinogenolytic agent. Purified fraction of pit viper venom, cleaves fibrinogen.
  • Placebo Drug
    Intervention Desc: 0.6 mL/kg/hr
    ARM 1: Kind: Experimental
    Label: Intravenous Placebo
    Description: Intravenous placebo at a rate of 0.6 mL/kg/hr for 2 or 3 hours depending on the pretreatment fibrinogen level.
  • Ancrod (Viprinex) Biological
    Intervention Desc: 0.167 IU/kg/hr IV for 2-3 hours
    ARM 1: Kind: Experimental
    Label: Intravenous ancrod
    Description: Intravenous ancrod infused at a rate of 0.167 IU/kg/hr (0.6 mL/kg/hr) for 2 or 3 hours depending on the pretreatment fibrinogen level.

Trial Design

  • Allocation: Randomized
  • Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
  • Purpose: Treatment
  • Endpoint: Safety/Efficacy Study
  • Intervention: Parallel Assignment

Patient Involvement

Patients receive a one-time, 2-3 hour infusion of ancrod or placebo within six hours of the initial symptom onset of their ischemic stroke, and are then followed for three months to collect information on their functional status.


Type Measure Time Frame Safety Issue
Primary Modified Rankin Score - responder analysis 90 days No
Secondary Barthel Index, NIHSS 90 days No