NICE, France, May 14 /PRNewswire-FirstCall/ -- Neurobiological Technologies, Inc. (NTI(R)) (Nasdaq: NTII) reported for the first time at the European Stroke Conference detailed analyses supporting the dosing regimen in NTI's two ongoing Phase 3 studies of Viprinex(TM) (ancrod) for ischemic stroke. The company also provided information as to why it believes these studies are more likely to be successful in treating ischemic stroke than previous Phase 3 clinical trials conducted by others using the same snake venom-derived agent.
David E. Levy, M.D., Vice President, Clinical Development at NTI, presented his retrospective analysis of data from the prior North American and European Phase 3 stroke trials of Viprinex involving more than 1,700 patients. Viprinex has been shown to rapidly reduce blood levels of fibrinogen, an important agent involved in blood clotting and blood viscosity. Elevated fibrinogen levels are a risk factor for stroke and may be associated with greater stroke disability. Prior studies with Viprinex that target fibrinogen have shown a benefit from this approach.
"The prior studies of Viprinex showed improved efficacy, but used a dosing regimen that infused the drug over five to seven days, which kept fibrinogen levels low for too long, compromising safety," said Dr. Levy, the key presenter. "NTI has changed the treatment paradigm to a single, three-hour intravenous dose designed to reduce fibrinogen levels quickly, while avoiding the prolonged low fibrinogen levels that were tried previously. Stopping the infusion after three hours permits fibrinogen to return to normal levels much faster than when the drug is given over five to seven days."
Dosing in the successful North American Phase 3 trial was compared to dosing in the unsuccessful European Phase 3 trial. The analyses showed that European patients initially infused with Viprinex at the most rapid rate had statistically significant efficacy with Viprinex versus placebo. The analysis also showed that patients across both studies whose mean fibrinogen levels were kept above a certain threshold over the entire five to seven day treatment period had a rate of symptomatic intracranial hemorrhage that was substantially lower than in those with lower mean fibrinogen levels over the same five to seven day period. These data suggest that rapid initial lowering of fibrinogen is associated with better efficacy, but for safety purposes fibrinogen should be allowed to return back up to its higher level after treatment.
"Viprinex, a novel Fibrinogen Reducing Agent, is an enzyme that reduces levels of fibrinogen, the primary protein involved in blood clotting," said Warren W. Wasiewski, M.D., Vice President and Chief Medical Officer of Neurobiological Technologies, Inc. and a second author of the retrospective analysis. "Reducing fibrinogen in the blood lowers blood viscosity, which may improve blood flow. Additionally, as the fibrinogen is broken down, natural mechanisms are activated to dissolve blood clots that have already formed. Since Viprinex acts in the blood for a longer period of time than existing therapies for treatment of stroke, the effect of Viprinex on brain blood flow should be sustained longer. We believe that a single infusion of Viprinex would be better than a prolonged infusion for treating ischemic stroke."
Previous studies have shown that Viprinex can be effective when administered up to six hours after the onset of stroke symptoms, which could significantly expand the number of people who can be treated. The only currently approved drug therapy for ischemic stroke is limited to a three-hour window.
With more than 700,000 patients experiencing stroke each year in the United States, and existing therapies limited to the first three hours after onset of stroke symptoms, there is a substantial unmet medical need to increase treatment options that are safe and effective to more stroke patients.
The Ancrod Stroke Program I and II studies are Phase 3 clinical trials currently underway at sites in the United States, various European countries, Russia, Australia, New Zealand, South Africa, Israel and Taiwan.
About Neurobiological Technologies:
Neurobiological Technologies, Inc. is a biopharmaceutical company focused on developing novel, first-in-class agents for central nervous system conditions and other serious unmet medical needs. The Company's most advanced product candidate, Viprinex(TM) (ancrod), is in Phase 3 clinical testing as a novel investigational drug with multiple mechanisms of action that is specifically designed to double the time period that patients can be treated after the onset of a stroke. NTI also has the right to receive royalty payments from sales of Namenda(R) (memantine HCL), an approved drug marketed for Alzheimer's disease, and the right to receive payments from the development and marketing of XERECEPT(R) (corticorelin acetate injection), an investigational drug in Phase 3 clinical development for swelling associated with brain tumors. Additionally, NTI has rights to two compounds in early-stage development for Alzheimer's and Huntington's diseases.
Forward Looking Statements:
Except for the historical information contained herein, the matters discussed in this press release are forward-looking statements that involve risks and uncertainties, including uncertainties regarding the successful completion of clinical trials for Viprinex, as well as other risks detailed from time to time in our Annual Report of Form 10-K and other filings with the Securities and Exchange Commission. There can be no assurance that Viprinex will prove to be safe or effective in the ongoing Phase 3 trials or that it will receive regulatory approval for commercialization. Actual results may differ materially from those projected. These forward-looking statements represent our judgment as of the date of the release. We undertake no obligation to update these forward-looking statements.
|SOURCE Neurobiological Technologies, Inc.|
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