FDA label 0e9925c8-d7f9-5cea-e063-6294a90a50a2

5.1 Diminished Antiplatelet Activity in Patients with Impaired CYP2C19 Function Clopidogrel is a prodrug. Inhibition of platelet aggregation by clopidogrel is achieved through an active metabolite. The metabolism of clopidogrel to its active metabolite can be impaired by genetic variations in CYP2C19 [see Boxed Warning]. The metabolism of clopidogrel can also be impaired by drugs that inhibit CYP2C19, such as omeprazole or esomeprazole. Avoid concomitant use of clopidogrel with omeprazole or esomeprazole because both significantly reduce the antiplatelet activity of clopidogrel [see Drug Interactions (7.1)]. 5.2 General Risk of Bleeding Thienopyridines, including clopidogrel, increase the risk of bleeding. Thienopyridines inhibit platelet aggregation for the lifetime of the platelet (7-10 days). Because the half-life of clopidogrel’s active metabolite is short, it may be possible to restore hemostasis by administering exogenous platelets; however, platelet transfusions within 4 hours of the loading dose or 2 hours of the maintenance dose may be less effective. 5.3 Discontinuation of Clopidogrel Discontinuation of clopidogrel increases the risk of cardiovascular events. If clopidogrel must be temporarily discontinued (e.g., to treat bleeding or for surgery with a major risk of bleeding), restart it as soon as possible. When possible, interrupt therapy with clopidogrel for five days prior to such surgery. Resume clopidogrel as soon as hemostasis is achieved. 5.4 Thrombotic Thrombocytopenic Purpura (TTP) TTP, sometimes fatal, has been reported following use of clopidogrel, sometimes after a short exposure (<2 weeks). TTP is a serious condition that requires urgent treatment including plasmapheresis (plasma exchange). It is characterized by thrombocytopenia, microangiopathic hemolytic anemia (schistocytes [fragmented RBCs] seen on peripheral smear), neurological findings, renal dysfunction, and fever [see Adverse Reactions (6.2)]. 5.5 Cross-Reactivity among Thienopyridines Hypersensitivity including rash, angioedema or hematologic reaction has been reported in patients receiving clopidogrel, including patients with a history of hypersensitivity or hematologic reaction to other thienopyridines [see Contraindications(4.2)and Adverse Reactions(6.2)].

The following serious adverse reactions are discussed below and elsewhere in the labeling: Bleeding [see Warnings and Precautions (5.2)] Thrombotic thrombocytopenic purpura [see Warnings and Precautions (5.4)] 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions and durations of follow-up, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Clopidogrel has been evaluated for safety in more than 54,000 patients, including over 21,000 patients treated for one year or more. The clinically important adverse reactions observed in trials comparing clopidogrel plus aspirin to placebo plus aspirin and trials comparing clopidogrel alone to aspirin alone are discussed below. Bleeding CURE In CURE, clopidogrel use with aspirin was associated with an increase in major bleeding (primarily gastrointestinal and at puncture sites) compared to placebo with aspirin (see Table 1). The incidence of intracranial hemorrhage (0.1%) and fatal bleeding (0.2%) were the same in both groups. Other bleeding events that were reported more frequently in the clopidogrel group were epistaxis, hematuria, and bruise. The overall incidence of bleeding is described in Table 1. Table 1: CURE Incidence of Bleeding Complications (% patients) Event Clopidogrel (+ aspirin) (n=6,259) Placebo (+ aspirin) (n=6,303) * Life-threatening and other major bleeding. † Led to interruption of study medication. Major bleeding* 3.7 2.7 Life-threatening bleeding 2.2 1.8 Fatal 0.2 0.2 5 g/dL hemoglobin drop 0.9 0.9 Requiring surgical intervention 0.7 0.7 Hemorrhagic strokes 0.1 0.1 Requiring inotropes 0.5 0.5 Requiring transfusion (≥4 units) 1.2 1 Other major bleeding 1.6 1 Significantly disabling 0.4 0.3 Intraocular bleeding with significant loss of vision 0.05 0.03 Requiring 2 to 3 units of blood 1.3 0.9 Minor bleeding† 5.1 2.4 COMMIT In COMMIT, similar rates of major bleeding were observed in the clopidogrel and placebo groups, both of which also received aspirin (see Table 2). Table 2: Incidence of Bleeding Events in COMMIT (% patients) Type of Bleeding Clopidogrel(+ aspirin) (n=22,961) Placebo (+ aspirin) (n=22,891) p-value * Major bleeds were cerebral bleeds or non-cerebral bleeds thought to have caused death or that required transfusion. Major* noncerebral or cerebral bleeding Major noncerebral Fatal Hemorrhagic stroke Fatal 0.6 0.4 0.2 0.2 0.2 0.5 0.3 0.2 0.2 0.2 0.59 0.48 0.9 0.91 0.81 Other noncerebral bleeding (non-major) 3.6 3.1 0.005 Any noncerebral bleeding 3.9 3.4 0.004 CAPRIE (clopidogrel vs Aspirin) In CAPRIE, gastrointestinal hemorrhage occurred at a rate of 2% in those taking clopidogrel versus 2.7% in those taking aspirin; bleeding requiring hospitalization occurred in 0.7% and 1.1%, respectively. The incidence of intracranial hemorrhage was 0.4% for clopidogrel compared to 0.5% for aspirin. Other bleeding events that were reported more frequently in the clopidogrel group were epistaxis and hematoma. Other Adverse Events In CURE and CHARISMA, which compared clopidogrel plus aspirin to aspirin alone, there was no difference in the rate of adverse events (other than bleeding) between clopidogrel and placebo. In CAPRIE, which compared clopidogrel to aspirin, pruritus was more frequently reported in those taking clopidogrel. No other difference in the rate of adverse events (other than bleeding) was reported. 6.2 Postmarketing Experience The following adverse reactions have been identified during postapproval use of clopidogrel. Because these reactions are reported voluntarily from a population of an unknown size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Hemorrhages, including those with fatal outcome, have been reported in patients treated with clopidogrel. Blood and lymphatic system disorders: Agranulocytosis, aplastic anemia/pancytopenia, thrombotic thrombocytopenic purpura (TTP), acquired hemophilia A Gastrointestinal disorders: Colitis (including ulcerative or lymphocytic colitis), pancreatitis, stomatitis, gastric/duodenal ulcer, diarrhea General disorders and administration site condition: Fever Hepatobiliary disorders: Acute liver failure, hepatitis (noninfectious), abnormal liver function test Immune system disorders: Hypersensitivity reactions, anaphylactoid reactions, serum sickness Musculoskeletal, connective tissue and bone disorders: Myalgia, arthralgia, arthritis Nervous system disorders: Taste disorders, headache, ageusia Psychiatric disorders: Confusion, hallucinations Respiratory, thoracic and mediastinal disorders: Bronchospasm, interstitial pneumonitis, eosinophilic pneumonia Renal and urinary disorders: Increased creatinine levels Skin and subcutaneous tissue disorders: Maculopapular, erythematous or exfoliative rash, urticaria, bullous dermatitis, eczema, toxic epidermal necrolysis, Stevens-Johnson syndrome, acute generalized exanthematous pustulosis (AGEP), angioedema, drug-induced hypersensitivity syndrome, drug rash with eosinophilia and systemic symptoms (DRESS), erythema multiforme, lichen planus, generalized pruritus Vascular disorders: Vasculitis, hypotension