Plavix (clopidogrel tablets) is a thienopyridine class inhibitor of P2Y 12 ADP platelet receptors. Chemically it is methyl (+)-( S )-α-(2-chlorophenyl)-6,7-dihydrothieno[3,2-c]pyridine-5(4 H )-acetate sulfate (1:1). The empirical formula of clopidogrel bisulfate is C 16 H 16 ClNO 2 S•H 2 SO 4 and its molecular weight is 419.9. The structural formula is as follows: Clopidogrel bisulfate is a white to off-white powder. It is practically insoluble in water at neutral pH but freely soluble at pH 1. It also dissolves freely in methanol, dissolves sparingly in methylene chloride, and is practically insoluble in ethyl ether. It has a specific optical rotation of about +56°. Plavix for oral administration is provided as either pink, round, biconvex, debossed, film-coated tablets containing 97.875 mg of clopidogrel bisulfate which is the molar equivalent of 75 mg of clopidogrel base or pink, oblong, debossed, film-coated tablets containing 391.5 mg of clopidogrel bisulfate which is the molar equivalent of 300 mg of clopidogrel base. Each tablet contains hydrogenated castor oil, hydroxypropyl cellulose, mannitol, microcrystalline cellulose, and polyethylene glycol 6000 as inactive ingredients. The pink film coating contains ferric oxide, hypromellose 2910, lactose monohydrate, titanium dioxide, and triacetin. The tablets are polished with Carnauba wax. Chemical Structure

Plavix is a P2Y 12 platelet inhibitor indicated for: Acute coronary syndrome – For patients with non–ST-segment elevation ACS (unstable angina [UA]/non–ST-elevation myocardial infarction [NSTEMI]), Plavix has been shown to reduce the rate of myocardial infarction (MI) and stroke. – For patients with ST-elevation myocardial infarction (STEMI), Plavix has been shown to reduce the rate of MI and stroke. Recent MI, recent stroke, or established peripheral arterial disease. Plavix has been shown to reduce the rate of MI and stroke

Acute Coronary Syndrome (ACS) Plavix is indicated to reduce the rate of myocardial infarction (MI) and stroke in patients with non–ST-segment elevation ACS (unstable angina [UA]/non–ST-elevation myocardial infarction [NSTEMI]), including patients who are to be managed medically and those who are to be managed with coronary revascularization. Plavix should be administered in conjunction with aspirin. Plavix is indicated to reduce the rate of myocardial infarction and stroke in patients with acute ST-elevation myocardial infarction (STEMI) who are to be managed medically. Plavix should be administered in conjunction with aspirin

Recent MI, Recent Stroke, or Established Peripheral Arterial Disease In patients with established peripheral arterial disease or with a history of recent myocardial infarction (MI) or recent stroke Plavix is indicated to reduce the rate of MI and stroke.

75 mg tablets: Pink, round, biconvex, film-coated tablets debossed with "75" on one side and "1171" on the other 300 mg tablets: Pink, oblong, film-coated tablets debossed with "300" on one side and "1332" on the other Film-coated tablets: 75 mg, 300 mg

Acute coronary syndrome – Initiate Plavix with a single 300 mg oral loading dose and then continue at 75 mg once daily. – Initiating Plavix without a loading dose will delay establishment of an antiplatelet effect by several days. Recent MI, recent stroke, or established peripheral arterial disease: 75 mg once daily orally without a loading dose

Acute Coronary Syndrome In patients who need an antiplatelet effect within hours, initiate Plavix with a single 300 mg oral loading dose and then continue at 75 mg once daily. Initiating Plavix without a loading dose will delay establishment of an antiplatelet effect by several days

Recent MI, Recent Stroke, or Established Peripheral Arterial Disease 75 mg once daily orally without a loading dose .

CYP2C19 inhibitors: Avoid concomitant use of omeprazole or esomeprazole. Bleeding: Plavix increases risk of bleeding. Discontinuation: Premature discontinuation increases risk of cardiovascular events. Discontinue 5 days prior to elective surgery that has a major risk of bleeding. Thrombotic thrombocytopenic purpura (TTP) has been reported. Cross-reactivity among thienopyridines has been reported. 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 . The metabolism of clopidogrel can also be impaired by drugs that inhibit CYP2C19, such as omeprazole or esomeprazole. Avoid concomitant use of Plavix with omeprazole or esomeprazole because both significantly reduce the antiplatelet activity of Plavix

General Risk of Bleeding P2Y12 inhibitors (thienopyridines), including Plavix, increase the risk of bleeding. P2Y12 inhibitors (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. Use of drugs that induce the activity of CYP2C19 would be expected to result in increased drug levels of the active metabolite of clopidogrel and might potentiate the bleeding risk. As a precaution, avoid concomitant use of strong CYP2C19 inducers . Risk factors for bleeding include concomitant use of other drugs that increase the risk of bleeding (e.g., anticoagulants, antiplatelet agents, and chronic use of NSAIDs)

Discontinuation of Plavix Discontinuation of Plavix increases the risk of cardiovascular events. If Plavix 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 Plavix for five days prior to such surgery. Resume Plavix as soon as hemostasis is achieved

Thrombotic Thrombocytopenic Purpura (TTP) TTP, sometimes fatal, has been reported following use of Plavix, 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

Cross-Reactivity among Thienopyridines Hypersensitivity including rash, angioedema or hematologic reaction has been reported in patients receiving Plavix, including patients with a history of hypersensitivity or hematologic reaction to other thienopyridines .

CYP2C19 inducers: Increases levels of clopidogrel active metabolite and increases platelet inhibition. Opioids: Decreased exposure to clopidogrel. Consider use of parenteral antiplatelet agent. Nonsteroidal anti-inflammatory drugs (NSAIDs), warfarin, selective serotonin and serotonin norepinephrine reuptake inhibitors (SSRIs, SNRIs): Increases risk of bleeding. ( 7.4 , 7.5 , 7.6 ) Other Antiplatelet Agents: Increases the risk of bleeding due to an additive effect. Repaglinide (CYP2C8 substrates): Increases substrate plasma concentrations

CYP2C19 Inducers Since clopidogrel is metabolized to its active metabolite partly by CYP2C19, use of drugs that induce the activity of this enzyme would be expected to result in increased drug levels of the active metabolite of clopidogrel. Rifampin strongly induces CYP2C19 resulting to both an increase level of clopidogrel active metabolite and platelet inhibition, which in particular might potentiate the risk of bleeding. As a precaution, avoid concomitant use of strong CYP2C19 inducers

CYP2C19 Inhibitors Clopidogrel is metabolized to its active metabolite in part by CYP2C19. Concomitant use of drugs that inhibit the activity of this enzyme results in reduced plasma concentrations of the active metabolite of clopidogrel and a reduction in platelet inhibition . Omeprazole or Esomeprazole Avoid concomitant use of Plavix with omeprazole or esomeprazole. In clinical studies, omeprazole was shown to reduce significantly the antiplatelet activity of Plavix when given concomitantly or 12 hours apart. A similar reduction in antiplatelet activity was observed with esomeprazole when given concomitantly with Plavix. Dexlansoprazole, lansoprazole, and pantoprazole had less effect on the antiplatelet activity of Plavix than did omeprazole or esomeprazole

Opioids As with other oral P2Y 12 inhibitors, coadministration of opioid agonists delay and reduce the absorption of clopidogrel, presumably because of slowed gastric emptying, resulting in reduced exposure to its metabolites . Consider the use of a parenteral antiplatelet agent in acute coronary syndrome patients requiring coadministration of morphine or other opioid agonists

Nonsteroidal Anti-inflammatory Drugs (NSAIDs) Coadministration of Plavix and NSAIDs increases the risk of gastrointestinal bleeding

Warfarin (CYP2C9 Substrates) Although the administration of clopidogrel 75 mg per day did not modify the pharmacokinetics of S-warfarin (a CYP2C9 substrate) or INR in patients receiving long-term warfarin therapy, coadministration of Plavix with warfarin increases the risk of bleeding because of independent effects on hemostasis. However, at high concentrations in vitro , clopidogrel inhibits CYP2C9

SSRIs and SNRIs Since selective serotonin reuptake inhibitors (SSRIs) and serotonin norepinephrine reuptake inhibitors (SNRIs) affect platelet activation, the concomitant administration of SSRIs and SNRIs with clopidogrel may increase the risk of bleeding

Other Antiplatelet Agents Coadministration of antiplatelet agents increase the risk of bleeding due to an additive effect. Promptly evaluate any signs or symptoms of blood loss if patients are treated concomitantly with other antiplatelet agents

Repaglinide (CYP2C8 Substrates) The acyl-β-glucuronide metabolite of clopidogrel is a strong inhibitor of CYP2C8. Plavix can increase the systemic exposure to drugs that are primarily cleared by CYP2C8, thereby needing dose adjustment and appropriate monitoring. Plavix increased repaglinide exposures by 3.9-fold to 5.1-fold . Avoid concomitant use of repaglinide with Plavix. If concomitant use cannot be avoided, initiate repaglinide at 0.5 mg before each meal and do not exceed a total daily dose of 4 mg. Increased frequency of glucose monitoring may be required during concomitant use.