New Study Shows Clexane(R) / Lovenox(R) (Enoxaparin Sodium Injection) is More Effective Than Unfractionated Heparin (UFH) for Preventing the Risk of Venous Thromboembolism (VTE) in Patients With Acute Ischemic Stroke

2006-12-13 09:37 1133

- The PREVAIL Study Showed That in Acute Ischemic Stroke Patients

Treated With Clexane(R) / Lovenox(R), the Risk of Having a VTE was

Lowered by a Significant 43% With no Significant Increase in

Clinically Important Bleedings When Compared to UFH

ORLANDO, Fla., Dec. 13 /Xinhua-PRNewswire/ -- Sanofi-aventis announced

today that the results of the PREVAIL (Prevention of VTE after Acute Ischemic

Stroke with LMWH Enoxaparin) study presented at the 48th American Society of

Hematology (ASH) annual meeting in Orlando demonstrated a significant 43%

reduction in venous thromboembolism (VTE) events with enoxaparin vs.

unfractionated heparin (UFH) in medically-ill patients who suffered an acute

ischemic stroke.

Among medically-ill patients, stroke patients are at an increased risk

for developing VTE. Without VTE prophylaxis, up to 75% of patients with

hemiplegia following stroke develop deep-vein thrombosis (DVT) and 20%

develop pulmonary embolism (PE)[1,2].

The primary efficacy endpoint of the study was the composite of

symptomatic or asymptomatic DVT, and/or symptomatic or fatal PE during the

treatment period.

The significant 43% relative risk reduction in VTE events observed with

enoxaparin vs. UFH for the primary efficacy endpoint (10.2 % vs. 18.1%;

p=0.0001) was associated with a consistent reduction in proximal DVT by 53%

(4.5% vs. 9.6%; p=0.0003).

There was no significant difference in clinically important bleedings

(1.3% vs. 0.7%, p=0.20), corresponding to the combination of both symptomatic

intracranial bleeding, the most serious complication, and major extracranial


The reduction in VTE risk was also observed in patients presenting with

different levels of stroke severity, with no significant difference in

clinically important bleedings.

"Balancing the benefits of lowering the risk of VTE while minimizing the

risk of bleeding is a very important element in choosing prophylactic

regimens for this particularly fragile patient population, as it combines the

usual factors of VTE in addition to the stroke context," said Dr. David

Sherman, Professor in the Division of Neurology in the Department of Medicine

at the University of Texas Health Science Center (UTHSC) in San Antonio, and

principal investigator of the study. "PREVAIL showed that enoxaparin, when

compared to UFH, had a superior efficacy with no significant increase in

clinically important bleedings. These data provide new evidence that suggests

enoxaparin can be used as VTE prophylaxis in this high risk population".

About Venous Thromboembolism (VTE)

Venous thromboembolism is a general term used to describe the formation

of a blood clot (thrombus) that blocks a vessel. This may occur in any part

of the venous system, but the most common manifestations are deep-vein

thrombosis (DVT), usually in the leg, and pulmonary embolism (PE).

VTE is also a common complication among individuals who have experienced

an acute ischemic stroke (AIS).


PREVAIL trial is the first large-scale, multinational, prospective,

randomized study which enrolled 1,762 ischemic stroke patients (stratified by

NIH Stroke Scale Score) in over 15 countries.

Patients confirmed with an acute ischemic stroke, were randomized within

48 hours of stroke symptoms to receive enoxaparin daily 40 mg SC or UFH 5000

IU SC Q 12 treatment for 10 days +/- 4 days with a follow up period of 90

days and stratified by NIH Stroke Scale Score (severe greater than or equal

to 14 and less severe <14).

The primary efficacy endpoint was the composite of symptomatic or

asymptomatic DVT, symptomatic ad / or fatal PE during the treatment period.

The primary safety endpoints included symptomatic intracranial bleeding,

major extracranial bleeding and all-cause mortality.

About Enoxaparin

Enoxaparin is an anticoagulant of the low molecular weight heparin (LMWH)

class. Its clinical applications are linked to its antithrombotic properties.

It is used to inhibit clot formation in venous or arterial vessels to avoid

potential acute or chronic complications of venous or arterial thrombosis

such as pulmonary embolism, myocardial infarction or death of cardiovascular

origin. As with all anticoagulants, the most frequently reported side effect

for enoxaparin is bleeding. Clinical indications for enoxaparin may vary from

one country to another.

About Sanofi-aventis

Sanofi-aventis is the world’s third largest pharmaceutical company,

ranking number one in Europe. Backed by a world-class R&D organization,

sanofi-aventis is developing leading positions in seven major therapeutic

areas: cardiovascular, thrombosis, oncology, metabolic diseases, central

nervous system, internal medicine, and vaccines. Sanofi-aventis is listed in

Paris (EURONEXT: SAN) and in New York (NYSE: SNY).

Notes to Editors

1. McCarthy ST, Turner J. Low-dose subcutaneous heparin in the prevention

of deep-vein thrombosis and pulmonary emboli following acute stroke.

Age Ageing 1986; 15: 84-8

2. McCarthy ST, Turner JJ, Robertson D, Hawkey CJ, Macey DJ. Low-dose

heparin as a prophylaxis against deep-vein thrombosis after acute

stroke. Lancet 1977: 2: 800-1.

Source: sanofi-aventis