Source: DGNews  |  Posted 4 years ago

By Rachel Tilley

GLASGOW, UK -- June 1, 2007 -- Clopidogrel reduced the risk of recurrent vascular events in Japanese patients with noncardioembolic stroke without the associated adverse risks of ticlopidine, according to researchers speaking at the 16[^]th[] annual European Stroke Conference (ESC).

Previous studies have shown that both clopidogrel and ticlopidine are more effective at reducing recurrent vascular events than aspirin, but clopidogrel has a more favourable safety profile.

This is the first head-to-head comparison of the safety and efficacy of clopidogrel and ticlopidine in a Japanese population, commented lead investigator Shinichiro Uchiyama, MD, PhD, Neurological Institute, Tokyo Women's Medical University, Tokyo, Japan.

The researchers combined the analysis of 2 phase 3 randomised, controlled studies that evaluated the safety and efficacy of clopidogrel and ticlopidine among Japanese people with a history of noncardioembolic stroke.

In the study, 941 patients received clopidogrel at 75 mg per day and 928 received ticlopidine at 200 mg per day; both groups were treated for 26 or 52 weeks.

Baseline characteristics were similar within and between the 2 studies, noted the researchers.

Results of the trial show that significantly fewer adverse drug reactions occurred in patients receiving clopidogrel compared with ticlopidine (35%, []P []<.001).

In addition, half the number of patients in the clopidogrel group experienced symptoms of hepatic dysfunction compared with the ticlopidine group (13.4% vs 25.6%, []P[] <.001). The researchers measured a lower serum level of the liver enzymes ALT, AST, gamma-GTP, and ALP, in patients treated with clopidogrel compared with the ticlopidine group ([]P[] <.001 for all).

Clopidogrel also reduced the haematological disorders seen with ticlopidine; the incidence of leukopaenia and neutropenia was more than halved in the clopidogrel group compared with the ticlopidine group ([]P[] <.001). However, the incidence of adverse hemorrhagic events was similar between the 2 groups (1.3% in clopidogrel vs 0.8% in ticlopidine, []P[] =.409).

The secondary objective of the study was to evaluate the combined incidence of recurrent vascular events in Japanese stroke patients up to 52 weeks. The researchers found that the incidence of recurrent vascular events did not differ between the clopidogrel and ticlopidine groups (2.6% vs 2.5%, []P []=.769), and that these vascular events were entirely attributable to cerebral infarction because no patient in either group had a myocardial infarction or vascular death.

"These results are comparable with those from Europe and North America, which suggest that clopidogrel has a superior safety profile but similar efficacy to ticlopidine," said Dr. Uchiyama.

He reiterated that this study is the first to directly compare ticlopidine with clopidogrel and to investigate the safety and efficacy of these agents in Japanese stroke patients.

Finally, he concluded, "now that clopidogrel is available in Japan, it should be the preferred antiplatelet treatment for the secondary prevention of cerebral infarction."

This study was funded by Daiichi Pharmaceutical Company and sanofi-aventis.

[[]Presentation title: The Safety and Efficacy of Clopidogrel versus Ticlopidine in Japanese Stroke Patients -- Combined Results of Two Phase III Multicentre Randomised Clinical Trials. Large Clinical Trials Abstract 02[]]