Ticlopidine can cause life-threatening hematological adverse reactions, including neutropenia/agranulocytosis, thrombotic thrombocytopenic purpura (TTP) and aplastic anemia.
Among 2048 patients in clinical trials in stroke patients, there were 50 cases (2.4%) of neutropenia (less than 1200 neutrophils/mm3), and the neutrophil count was below 450/mm3 in 17 of these patients (0.8% of the total population).
One case of thrombotic thrombocytopenic purpura was reported during clinical trials in stroke patients. Based on postmarketing data, US physicians reported about 100 cases between 1992 and 1997. Based on an estimated patient exposure of 2 million to 4 million, and assuming an event reporting rate of 10% (the true rate is not known), the incidence of ticlopidine-associated TTP may be as high as one case in every 2000 to 4000 patients exposed.
Aplastic anemia was not seen during clinical trials in stroke patients, but US physicians reported about 50 cases between 1992 and 1998. Based on an estimated patient exposure of 2 million to 4 million, and assuming an event reporting rate of 10% (the true rate is not known), the incidence of ticlopidine-associated aplastic anemia may be as high as one case in every 4000 to 8000 patients exposed.
Monitoring of Clinical and Hematologic Status
Severe hematological adverse reactions may occur within a few days of the start of therapy. The incidence of TTP peaks after about 3 to 4 weeks of therapy and neutropenia peaks at approximately 4 to 6 weeks. The incidence of aplastic anemia peaks after about 4 to 8 weeks of therapy. The incidence of the hematologic adverse reactions declines thereafter. Only a few cases of neutropenia, TTP, or aplastic anemia have arisen after more than 3 months of therapy.
Hematological adverse reactions cannot be reliably predicted by any identified demographic or clinical characteristics. During the first 3 months of treatment, patients receiving ticlopidine must, therefore, be hematologically and clinically monitored for evidence of neutropenia or TTP. If any such evidence is seen, ticlopidine should be immediately discontinued.
The detection and treatment of ticlopidine-associated hematological adverse reactions are further described under WARNINGS.
Published Studies Related to Ticlopidine
Exposure to oral S-ketamine is unaffected by itraconazole but greatly increased by ticlopidine. [2011.08]
This study examined drug-drug interactions of oral S-ketamine with the cytochrome P450 (CYP) 2B6 inhibitor ticlopidine and the CYP3A inhibitor itraconazole. In this randomized, blinded, crossover study, 11 healthy volunteers ingested 0.2 mg/kg S-ketamine after pretreatments with oral ticlopidine (250 mg twice daily), itraconazole (200 mg once daily), or placebo in 6-day treatment periods at intervals of 4 weeks...
Influence of Ginkgo biloba extract on the pharmacodynamic effects and pharmacokinetic properties of ticlopidine: an open-label, randomized, two-period, two-treatment, two-sequence, single-dose crossover study in healthy Korean male volunteers. [2010.02]
BACKGROUND:Ginkgo biloba extract is an herbal medicine used in the treatment of vascular disorders that may be coadministered with antiplatelet agents such as ticlopidine. Regulatory authorities requested evaluation of the pharmacodynamic and pharmacokinetic interactions between these entities, according to the drug-development guidance for fixed-dose combination formulations in Korea. OBJECTIVE: This study was performed to evaluate the potential pharmacodynamic and pharmacokinetic interactions between ticlopidine and Ginkgo biloba extract... CONCLUSIONS: In this small group of healthy Korean men, the addition of a single dose of Ginkgo biloba extract did not prolong the bleeding time and was not associated with additional antiplatelet effects compared with the administration of ticlopidine alone. The coadministration of Ginkgo biloba extract with ticlopidine was not associated with any significant changes in the pharmacokinetic profile of ticlopidine compared with ticlopidine administered alone. Copyright 2010. Published by EM Inc USA.
Comparison of the pharmacokinetics of ticlopidine between administration of a combined fixed-dose tablet formulation of ticlopidine 250 mg/ginkgo extract 80 mg, and concomitant administration of ticlopidine 250-mg and ginkgo extract 80-mg tablets: an open-label, two-treatment, single-dose, randomized-sequence crossover study in healthy Korean male volunteers. [2009.10]
BACKGROUND: Ticlopidine is an antiplatelet agent used for the prevention of vascular accidents. In clinical practice in Korea, ginkgo extract may be administered along with ticlopidine to enhance the inhibition of platelet aggregation. OBJECTIVE: To meet the requirements for marketing a combined fixed-dose formulation in Korea, the investigators compared the pharmacokinetic characteristics of ticlopidine in a combined fixed-dose tablet of ticlopidine/ginkgo extract with the concomitant administration of ticlopidine and ginkgo extract tablets... CONCLUSION: Administration of a single dose of a combined fixed-dose formulation of ticlopidine 250 mg/ ginkgo extract 80-mg tablets and concomitant administration of ticlopidine and ginkgo extract tablets did not result in statistically significant differences in the pharmacokinetics of ticlopidine in these healthy Korean male volunteers.
The safety and efficacy of clopidogrel versus ticlopidine in Japanese stroke patients: combined results of two Phase III, multicenter, randomized clinical trials. [2009.06]
Two Phase III studies comparing the safety and efficacy of clopidogrel with ticlopidine as antiplatelet agents for the secondary prevention of vascular events in patients with prior stroke were performed in Japan. Both studies were randomized, double-blind, double-dummy comparative trials with the primary objective of comparing the clinical safety of treatment with either clopidogrel or ticlopidine for up to 12 months...
Quantitative determination of ticlopidine hydrochloride in human plasma by high-performance liquid chromatography-electronspray ionization mass spectrometry. 
A sensitive, selective and simple high performance liquid chromatographyelectrospray ionization-mass spectrometry (HPLC-ESI-MS) was developed and validated for the quantification of ticlopidine hydrochloride (CAS 53885-35-1) in human plasma using loratadine (CAS 79794-75-5) as internal standard (IS)...
Clinical Trials Related to Ticlopidine
Effect of Itraconazole and Ticlopidine on the Pharmacokinetics and Pharmacodynamics of Oral Tramadol [Recruiting]
Tramadol is an opioid analgesic, which is widely used in the treatment of acute and
neuropathic pain. After oral administration, tramadol is rapidly and almost completely
absorbed. Tramadol is extensively metabolised by O- and N-demethylation, which are catalysed
by the liver CYP-450 enzymes. O-desmethyltramadol is an active metabolite and its formation
is catalysed by CYP2D6. The formation of inactive metabolites is catalysed by CYP3A4 and
2B6. This study is aimed to investigate the possible interaction of oral tramadol with
itraconazole and ticlopidine, which are inhibitors of CYP3A4 and 2B6. Twelve healthy male or
female adult non-smoking volunteers aged 18-40 years with body weights within ±15% of the
ideal weight for height are taken into the study. Primary endpoints of the study are plasma
concentrations of tramadol and its metabolites.
Safety Evaluation of Clopidogrel Sulfate in Patients With Peripheral Arterial Disease [Recruiting]
- To evaluate whether 12 weeks of clopidogrel is superior to ticlopidine in terms of
lower risk of the safety events of interests in patients with peripheral arterial
- To compare the risk of bleeding adverse events, serious adverse events and overall
safety of clopidogrel with ticlopidine
- To compare the risk of vascular events of clopidogrel with ticlopidine
- To document the long-term safety of clopidogrel for a total of 52 weeks
- To document the vascular events of clopidogrel for a total of 52 weeks
Safety Evaluation of Clopidogrel Sulfate in Patients With Stable Angina/Old Myocardial Infarction to Whom Percutaneous Coronary Intervention is Being Planned [Recruiting]
- To evaluate whether 12 weeks of clopidogrel is superior to ticlopidine in terms of
lower risk of the safety events of interest in patients with stable angina (SA) or old
myocardial infarction (OMI) to which percutaneous coronary intervention (PCI) is being
- To compare the incidence of adverse events, adverse drug reactions and bleeding events
in patients treated with clopidogrel versus ticlopidine.
- To compare the incidence of major adverse cardiac events (MACE) and major adverse
cardiac and cerebrovascular events (MACCE) in patients treated with clopidogrel versus
- To evaluate the long-term safety (adverse drug reactions, adverse events, safety events
of interest and bleeding events) of clopidogrel for a total of 52 weeks
- To evaluate MACE and MACCE of clopidogrel for a total of 52 weeks
Antiplatelet Therapy to Prevent Stroke in African Americans [Completed]
Clopidogrel Resistance and Embolism in Carotid Artery Stenting [Recruiting]
The purpose of this study is to evaluate the efficacy and safety of the ticlopidine + ginko
biloba compared to clopidogrel in clopidogrel resistant patients undergoing carotid artery
stent placement. The investigators hypothesized that ticlopidine + ginko biloba is superior
than clopidogrel in terms of post-stent ischemic lesions in these patients without serious