Navigation Links
Bat Saliva-Based Stroke Drug Disappoints in Trial
Date:12/18/2008

But the study's design may be to blame for desmoteplase's poor showing, researchers say

THURSDAY, Dec. 18 (HealthDay News) -- An experimental clot-busting drug derived from the saliva of the vampire bat has failed to reduce stroke damage in a major trial.

But hope for the drug, called desmoteplase, remains alive, experts say, because the study may not have been large enough to provide clear results.

"The sample size was underpowered to detect any benefit," said study co-author Dr. Anthony J. Furlan, chairman of neurology at Case Western Reserve University, in Cleveland. "The simplest answer is that stroke is an extremely heterogeneous condition, and it is difficult to predict what the outcomes will be from a smaller size population."

Two earlier and smaller studies showed a benefit when desmoteplase was given intravenously to reopen brain arteries blocked by clots. But there was no significant difference in outcome in the latest trial, called DIAS-2, between stroke victims given desmoteplase and those who got a placebo, said a report to be published online on Dec. 17 in The Lancet Neurology.

But there remains vigorous debate about the best method to use in selecting those stroke patients who will be treated in the next trial, which is in the planning stage, Furlan added.

Desmoteplase was originally spotted in the saliva of the vampire bat, which uses the chemical to keep its victims' blood flowing freely, so it can suck a full meal.

The drug is contending to replace tissue plasminogen activator (tPA), the only current treatment for ischemic strokes, which are caused by blockage of a blood vessel. Most strokes are ischemic strokes; tPA is given by intravenous injection and works quickly to dissolve clots.

"But tPA must be given within three hours of a stroke, so only a small percentage of patients can get the treatment," Furlan noted. "We hope to triple that window to nine hours with desmoteplase."

But the strategy didn't work in DIAS-2, which included 186 people with strokes. A total of 123 patients received either a high or low dose of desmoteplase, while 63 got a placebo.

The death rate was actually higher for those who got the drug -- 11 percent in the low-dose group and 21 percent in the high-dose group, compared to 6 percent for those given a placebo.

So it's back to the drawing board, the researchers said, and one big question is whether the high-tech methods used to select participants in the trial were too sophisticated to be reliable.

DIAS-2 neurologists used either computerized tomography or magnetic resonance scanning to detect what they formally called "mismatches" -- brain areas that have been affected by the stroke but are not yet dead.

"There is a core area of tissue that is dead," Furlan explained. "Around that area are brain cells that are not yet dead, so they can be saved."

That is the theory, anyway. But it's a theory that some of the neurologists involved with the new drug are questioning.

"The current mismatch model is insufficient to identify those patients who would benefit," Furlan said. "We need a more sophisticated mismatch model."

But another school of thought among neurologists is that a simpler, rather than more complex, method of choosing trial participants might be better.

"There is some controversy about the design of the next trial," Furlan said. "Maybe we can select patients simply by determining whether a major artery is blocked, instead of the mismatch. The main way patients would be enrolled is by looking to see if a major artery is blocked out to nine hours, rather than for mismatch."

No firm start date has been set for DIAS-3, said Furlan, who is on the safety committee for the proposed trial.

The trial was funded by German drug company PAION Deutschland GmbH and U.S.-based Forest Laboratories, which had been working together to develop desmoteplase.

More information

Ischemic stroke and is treatment are explained by the U.S. Library of Medicine.



SOURCES: Anthony J. Furlan, professor, chairman, neurology, Case Western Reserve University, Cleveland; February 2009 Lancet Neurology


'/>"/>
Copyright©2008 ScoutNews,LLC.
All rights reserved  

Related medicine news :

1. Study, meta-analysis examine factors associated with death from heatstroke
2. High alcohol consumption increases stroke risk among Chinese men
3. Heavy Drinking Boosts Stroke Risk for Chinese Men
4. High alcohol consumption increases stroke risk, Tulane study says
5. Broad-based group of physicians calls for improvement in stroke treatment
6. Continued Statin Use Boosts Post-Stroke Outcomes
7. U.S. Initiative Seeks to Boost Hispanic Stroke Awareness
8. Stopping Statins After Stroke Doubles Death Risk
9. Can brain-injured, partially-blind stroke patients regain some of their lost vision?
10. REACH Registry Highlights That Patients With Peripheral Arterial Disease (PAD) Suffer High Rates of Heart Attack, Stroke, Hospitalization, and Death
11. Link Between Air Pollution, Stroke Gets Clearer
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Bat Saliva-Based Stroke Drug Disappoints in Trial
(Date:1/23/2017)... ... January 23, 2017 , ... The Masters of Science ... evaluation leaders with decades of experience who remain current practitioners in the field. ... system, there is a renewed demand for versatile, data-driven leadership.The American University’s MS ...
(Date:1/23/2017)... ... January 23, 2017 , ... Moisture measurement is a ... method is paramount to success. Selecting an inappropriate measurement method can cause costly ... use the same equipment. Rare or expensive substances are wasted and production may ...
(Date:1/23/2017)... ... January 23, 2017 , ... Gynecology Associates of ... gynecological services for women of all ages. The staff of Gynecology ... of reproductive services from routine health screenings to diagnosing and treating female concerns ...
(Date:1/23/2017)... ... ... “Some Infallible Characteristics of Christ”: a fascinating and entrancing novel exploring the ... of published author, Rev. Dr. Robert W. Thomas, the third of seven siblings. He ... nineteen, a pastor for over fifteen years. He is a graduate of N.C. College ...
(Date:1/22/2017)... ... January 22, 2017 , ... Medical lab testing through hospitals and ... a simple test will take days to arrive to the end customer, having to ... access to their lab tests, bypassing the cost and delay of traditional means. Now ...
Breaking Medicine News(10 mins):
(Date:1/23/2017)... Jan 23, 2017 Research and Markets has announced ... Trends - Product - Forecast to 2025" report to their offering. ... Report Highlights: ... market trends to identify the investment opportunities Market forecasts ... Key market trends across the business segments, Regions and Countries ...
(Date:1/23/2017)... Jan. 23, 2017  Using Astute Medical,s ... risk for acute kidney injury (AKI) after open-heart ... care guidelines significantly improved outcomes by ... more than 33 percent, according to a ... Intensive Care Medicine. Experience ...
(Date:1/23/2017)... January 23, 2017 Ahead of today,s trading ... how they have fared at the close: Kite Pharma Inc. (NASDAQ: ... OVAS ), and Regeneron Pharmaceuticals Inc. (NASDAQ: ... were relative laggards on Friday, January 20 th , 2017, down ... research reports on these stocks now at: ...
Breaking Medicine Technology: