quinine 300 MG Oral Tablet

INDICATIONS AND USAGE Quinine Sulfate Capsules, USP is an antimalarial drug indicated only for treatment of uncomplicated Plasmodium falciparum malaria. Quinine sulfate has been shown to be effective in geographical regions where resistance to chloroquine has been documented [see Clinical Studies ( 14 )]. Limitations of Use: Quinine Sulfate is not approved for: Treatment of severe or complicated P. falciparum malaria. Prevention of malaria. Treatment or prevention of nocturnal leg cramps [see Warnings and Precautions ( 5.1 )]. Quinine Sulfate Capsules, USP is an antimalarial indicated for treatment of uncomplicated Plasmodium falciparum malaria. ( 1 ) Limitations of Use: Quinine Sulfate is not approved for: Treatment of severe or complicated P. falciparum malaria. Prevention of malaria. Treatment or prevention of nocturnal leg cramps.

DOSAGE AND ADMINISTRATION Adults (≥ 16 years of age): 648 mg (two capsules) every 8 hours for 7 days ( 2.1 ). Patients with Severe Chronic Renal Impairment: One loading dose of 648 mg (two capsules) followed 12 hours later by 324 mg (one capsule) every 12 hours for 7 days ( 2.2 ). 2.1 Treatment of Uncomplicated P. falciparum Malaria For treatment of uncomplicated P. falciparum malaria in adults: Orally, 648 mg (two capsules) every 8 hours for 7 days [see Clinical Studies ( 14 )]. Quinine sulfate capsules, USP should be taken with food to minimize gastric upset [see Clinical Pharmacology ( 12.3 )]. 2.2 Renal Impairment In patients with acute uncomplicated malaria and severe chronic renal impairment, the following dosage regimen is recommended: one loading dose of 648 mg quinine sulfate capsules, USP followed 12 hours later by maintenance doses of 324 mg every 12 hours. The effects of mild and moderate renal impairment on the safety and pharmacokinetics of quinine sulfate are not known [see Use in Specific Populations ( 8.6 ) and Clinical Pharmacology ( 12.3 )]. 2.3 Hepatic Impairment Adjustment of the recommended dose is not required in mild (Child-Pugh A) or moderate (Child-Pugh B) hepatic impairment, but patients should be monitored closely for adverse effects of quinine. Quinine should not be administered in patients with severe (Child-Pugh C) hepatic impairment [ see Use in Specific Populations (8.7) and Clinical Pharmacology (12.3) ].

WARNINGS AND PRECAUTIONS Thrombocytopenia, including ITP and HUS/TTP, has been reported. Discontinue drug ( 5.2 ). Hemolytic Anemia: Monitor hemoglobin and hematocrit. Discontinue drug if hemolytic anemia occurs ( 5.3 ). QT Prolongation and Ventricular Arrhythmias: Avoid concomitant use with drugs known to prolong QT interval ( 5.4 ). Avoid concomitant use with rifampin. Quinine sulfate treatment failures have been reported ( 5.5 ). Avoid concomitant use with neuromuscular blocking agents. Quinine sulfate may potentiate neuromuscular blockade and cause respiratory depression ( 5.6 ). Serious and Life-Threatening Hypersensitivity Reactions: Discontinue drug ( 4 , 5.7 ). Atrial Fibrillation and Flutter: Paradoxical increase in ventricular rate may occur. Closely monitor digoxin levels if used concomitantly ( 5.8 ). Hypoglycemia: Monitor for signs and symptoms ( 5.9 ). 5.1 Use of Quinine Sulfate Capsules for Treatment or Prevention of Nocturnal Leg Cramps Quinine sulfate capsules may cause unpredictable serious and life-threatening hematologic reactions including thrombocytopenia and hemolytic-uremic syndrome/thrombotic thrombocytopenic purpura (HUS/TTP) in addition to hypersensitivity reactions, QT prolongation, serious cardiac arrhythmias including torsades de pointes, and other serious adverse events requiring medical intervention and hospitalization. Chronic renal impairment associated with the development of TTP, and fatalities have also been reported. The risk associated with the use of Quinine Sulfate Capsules in the absence of evidence of its effectiveness for treatment or prevention of nocturnal leg cramps, outweighs any potential benefit in treating and/or preventing this benign, self-limiting condition [ see Boxed Warning and Contraindications (4) ]. 5.2 Thrombocytopenia Quinine-induced thrombocytopenia is an immune-mediated disorder. Severe cases of thrombocytopenia that are fatal or life threatening have been reported, including cases of HUS/TTP. Chronic renal impairment associated with the development of TTP has also been reported. Thrombocytopenia usually resolves within a week upon discontinuation of quinine. If quinine is not stopped, a patient is at risk for fatal hemorrhage. Upon re-exposure to quinine from any source, a patient with quinine-dependent antibodies could develop thrombocytopenia that is more rapid in onset and more severe than the original episode. 5.3 Hemolytic Anemia Acute hemolytic anemia has been reported in patients receiving quinine for treatment of malaria, including patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency. The cause for the acute hemolytic anemia in quinine-treated patients with malaria and its potential relationship with G6PD deficiency has not been determined. Closely monitor hemoglobin and hematocrit during quinine treatment. Quinine should be discontinued if patients develop acute hemolytic anemia. 5.4 QT Prolongation and Ventricular Arrhythmias QT interval prolongation has been a consistent finding in studies which evaluated electrocardiographic changes with oral or parenteral quinine administration, regardless of age, clinical status, or severity of disease. The maximum increase in QT interval has been shown to correspond with peak quinine plasma concentration [see Clinical Pharmacology ( 12.2 )] . Quinine sulfate has been rarely associated with potentially fatal cardiac arrhythmias, including torsades de pointes, and ventricular fibrillation. Quinine sulfate has been shown to cause concentration-dependent prolongation of the PR and QRS interval. At particular risk are patients with underlying structural heart disease and preexisting conduction system abnormalities, elderly patients with sick sinus syndrome, patients with atrial fibrillation with slow ventricular response, patients with myocardial ischemia or patients receiving drugs known to prolong the PR interval (e.g. verapamil) or QRS interval (e.g. flecainide or quinidine) [see Clinical Pharmacology ( 12.2 )]. Quinine sulfate is not recommended for use with other drugs known to cause QT prolongation, including Class IA antiarrhythmic agents (e.g., quinidine, procainamide, disopyramide), and Class III antiarrhythmic agents (e.g., amiodarone, sotalol, dofetilide). The use of macrolide antibiotics such as erythromycin should be avoided in patients receiving quinine sulfate. Fatal torsades de pointes was reported in an elderly patient who received concomitant quinine, erythromycin, and dopamine. Although a causal relationship between a specific drug and the arrhythmia was not established in this case, erythromycin is a CYP3A4 inhibitor and has been shown to increase quinine plasma levels when used concomitantly. A related macrolide antibiotic, troleandomycin, has also been shown to increase quinine exposure in a pharmacokinetic study [see Drug Interactions ( 7 )]. Quinine may inhibit the metabolism of certain drugs that are CYP3A4 substrates and are known to cause QT prolongation, e.g., astemizole, cisapride, terfenadine, pimozide, halofantrine and quinidine. Torsades de pointes has been reported in patients who received concomitant quinine and astemizole. Therefore, concurrent use of quinine sulfate with these medications, or drugs with similar properties, should be avoided [see Drug Interactions ( 7 )] . Concomitant administration of quinine sulfate with the antimalarial drugs, mefloquine or halofantrine, may result in electrocardiographic abnormalities, including QT prolongation, and increase the risk for torsades de pointes or other serious ventricular arrhythmias. Concurrent use of quinine sulfate and mefloquine may also increase the risk of seizures [see Drug Interactions ( 7 )] . Quinine sulfate should also be avoided in patients with known prolongation of QT interval and in patients with clinical conditions known to prolong the QT interval, such as uncorrected hypokalemia, bradycardia, and certain cardiac conditions [see Contraindications ( 4 )] . 5.5 Concomitant Use of Rifampin Treatment failures may result from the concurrent use of rifampin with quinine sulfate, due to decreased plasma concentrations of quinine, and concomitant use of these medications should be avoided [see Drug Interactions ( 7 )]. 5.6 Concomitant Use of Neuromuscular Blocking Agents The use of neuromuscular blocking agents should be avoided in patients receiving quinine sulfate. In one patient who received pancuronium during an operative procedure, subsequent administration of quinine resulted in respiratory depression and apnea. Although there are no clinical reports with succinylcholine or tubocurarine, quinine may also potentiate neuromuscular blockade when used with these drugs [see Drug Interactions ( 7 )] . 5.7 Hypersensitivity Serious hypersensitivity reactions reported with quinine sulfate include anaphylactic shock, anaphylactoid reactions, urticaria, serious skin rashes, including Stevens-Johnson syndrome and toxic epidermal necrolysis, angioedema, facial edema, bronchospasm, and pruritus. A number of other serious adverse reactions reported with quinine, including thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS), thrombocytopenia, immune thrombocytopenic purpura (ITP), blackwater fever, disseminated intravascular coagulation, leukopenia, neutropenia, granulomatous hepatitis, and acute interstitial nephritis may also be due to hypersensitivity reactions. Quinine sulfate should be discontinued in case of any signs or symptoms of hypersensitivity [see Contraindications ( 4 )]. 5.8 Atrial Fibrillation and Flutter Quinine sulfate should be used with caution in patients with atrial fibrillation or atrial flutter. A paradoxical increase in ventricular response rate may occur with quinine, similar to that observed with quinidine. If digoxin is used to prevent a rapid ventricular response, serum digoxin levels should be closely monitored, because digoxin levels may be increased with use of quinine [see Drug Interacti

CONTRAINDICATIONS Quinine sulfate is contraindicated in patients with the following: Prolongation of QT interval ( 4 ) Glucose-6-phosphate dehydrogenase (G6PD) deficiency ( 4 ) Myasthenia gravis ( 4 ) Known hypersensitivity to quinine, mefloquine, or quinidine ( 4 ) Optic neuritis ( 4 ) Quinine sulfate is contraindicated in patients with the following: • Prolonged QT interval. One case of a fatal ventricular arrhythmia was reported in an elderly patient with a prolonged QT interval at baseline, who received quinine sulfate intravenously for P. falciparum malaria [see WARNINGS AND PRECAUTIONS ( 5.3 )]. • Glucose-6-phosphate dehydrogenase (G6PD) deficiency. • Hemolysis can occur in patients with G6PD deficiency receiving quinine. • Known hypersensitivity reactions to quinine. • These include, but are not limited to, the following [see WARNINGS AND PRECAUTIONS ( 5.6 )] : • Thrombocytopenia • Idiopathic thrombocytopenia purpura (ITP) and Thrombotic thrombocytopenic purpura (TTP) • Hemolytic uremic syndrome (HUS) • Blackwater fever (acute intravascular hemolysis, hemoglobinuria, and hemoglobinemia) • Known hypersensitivity to mefloquine or quinidine: cross-sensitivity to quinine has been documented [see WARNINGS AND PRECAUTIONS ( 5.6 )]. • Myasthenia gravis. Quinine has neuromuscular blocking activity, and may exacerbate muscle weakness. • Optic neuritis. Quinine may exacerbate active optic neuritis [see ADVERSE REACTIONS ( 6 )] .

CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Quinine is an antimalarial agent [see CLINICAL PHARMACOLOGY ( 12.4 )] . 12.2 Pharmacodynamics QTc interval prolongation was studied in a double-blind, multiple dose, placebo- and positive-controlled crossover study in young (N=13, 20 to 39 years) and elderly (N=13, 65 to 78 years) subjects. After 7 days of dosing with quinine sulfate 648 mg three times daily, the maximum mean (95% upper confidence bound) differences in QTcI from placebo after baseline correction was 27.7 (32.2) ms. Prolongation of the PR and QRS interval was also noted in subjects receiving quinine sulfate. The maximum mean (95% upper confidence bound) difference in PR from placebo after baseline-correction was 14.5 (18.0) ms. The maximum mean (95% upper confidence bound) difference in QRS from placebo after baseline-correction was 11.5 (13.3) ms. [see WARNINGS AND PRECAUTIONS ( 5.3 )] . 12.3 Pharmacokinetics Absorption The oral bioavailability of quinine is 76 to 88% in healthy adults. Quinine exposure is higher in patients with malaria than in healthy subjects. After a single oral dose of quinine sulfate, the mean quinine T max was longer, and mean AUC and C max were higher in patients with uncomplicated P. falciparum malaria than in healthy subjects, as shown in Table 1 below. TABLE 1 Pharmacokinetic Parameters of Quinine in Healthy Subjects and Patients with Uncomplicated P. falciparum Malaria after a Single Dose Quinine Sulfate dose was 648 mg (approximately 8.7 mg/kg) in healthy subjects; and 10 mg/kg in patients with malaria of Oral Quinine Sulfate Capsules Healthy Subjects ( N = 23 ) Mean ± SD Uncomplicated P . falciparum Malaria Patients ( N = 15 ) Mean ± SD Dose (mg/kg) 8.7 10 T m a x (h) 2.8 ± 0.8 5.9 ± 4.7 C m a x (mcg/mL) 3.2 ± 0.7 8.4 AUC0–12 (mcg*h/mL) 28.0 73.0 Quinine sulfate capsules may be administered without regard to meals. When a single oral 324 mg capsule of quinine sulfate was administered to healthy subjects (N=26) with a standardized high-fat breakfast, the mean T max of quinine was prolonged to about 4.0 hours, but the mean C max and AUC 0-24h were similar to those achieved when quinine sulfate capsule was given under fasted conditions [see DOSAGE AND ADMINISTRATION ( 2.1 )] . Distribution In patients with malaria, the volume of distribution (Vd/F) decreases in proportion to the severity of the infection. In published studies with healthy subjects who received a single oral 600 mg dose of quinine sulfate, the mean Vd/F ranged from 2.5 to 7.1 L/kg. Quinine is moderately protein-bound in blood in healthy subjects, ranging from 69 to 92%. During active malarial infection, protein binding of quinine is increased to 78 to 95%, corresponding to the increase in α 1 -acid glycoprotein that occurs with malaria infection. Intra-erythrocytic levels of quinine are approximately 30 to 50% of the plasma concentration. Quinine penetrates relatively poorly into the cerebrospinal fluid (CSF) in patients with cerebral malaria, with CSF concentration approximately 2 to 7% of plasma concentration. In one study, quinine concentrations in placental cord blood and breast milk were approximately 32% and 31%, respectively, of quinine concentrations in maternal plasma. The estimated total dose of quinine secreted into breast milk was less than 2 to 3 mg per day [see USE IN SPECIFIC POPULATIONS ( 8.1 , 8.3 )] . Metabolism Quinine is metabolized almost exclusively via hepatic oxidative cytochrome P450 (CYP) pathways, resulting in four primary metabolites, 3-hydroxyquinine, 2´-quinone, O -desmethylquinine, and 10,11-dihydroxydihydroquinine. Six secondary metabolites result from further biotransformation of the primary metabolites. The major metabolite, 3-hydroxyquinine, is less active than the parent drug. In vitro studies using human liver microsomes and recombinant P450 enzymes have shown that quinine is metabolized mainly by CYP3A4. Depending on the in vitro experimental conditions, other enzymes, including CYP1A2, CYP2C8, CYP2C9, CYP2C19, CYP2D6, and CYP2E1 were shown to have some role in the metabolism of quinine. Elimination/Excretion Quinine is eliminated primarily via hepatic biotransformation. Approximately 20% of quinine is excreted unchanged in urine. Because quinine is reabsorbed when the urine is alkaline, renal excretion of the drug is twice as rapid when the urine is acidic than when it is alkaline. In various published studies, healthy subjects who received a single oral 600 mg dose of quinine sulfate exhibited a mean plasma clearance ranging from 0.08 to 0.47 L/h/kg (median value: 0.17 L/h/kg) with a mean plasma elimination half-life of 9.7 to 12.5 hours. In 15 patients with uncomplicated malaria who received a 10 mg/kg oral dose of quinine sulfate, the mean total clearance of quinine was slower (approximately 0.09 L/h/kg) during the acute phase of the infection, and faster (approximately 0.16 L/h/kg) during the recovery or convalescent phase. Extracorporeal Elimination: Administration of multiple-dose activated charcoal (50 grams administered 4 hours after quinine dosing followed by 3 further doses over the next 12 hours) decreased the mean quinine elimination half-life from 8.2 to 4.6 hours, and increased the mean quinine clearance by 56% (from 11.8 L/h to 18.4 L/h) in 7 healthy adult subjects who received a single oral 600 mg dose of quinine sulfate. Likewise, in 5 symptomatic patients with acute quinine poisoning who received multiple-dose activated charcoal (50 grams every 4 hours), the mean quinine elimination half-life was shortened to 8.1 hours in comparison to a half-life of approximately 26 hours in patients who did not receive activated charcoal [see OVERDOSAGE ( 10 ) ] . In 6 patients with quinine poisoning, forced acid diuresis did not change the half-life of quinine elimination (25.1 ± 4.6 hours vs. 26.5 ± 5.8 hours), or the amount of unchanged quinine recovered in the urine, in comparison to 8 patients not treated in this manner [see OVERDOSAGE ( 10 )] . Specific Populations Pediatric Patients: The pharmacokinetics of quinine in children (1.5 to 12 years old) with uncomplicated P. falciparum malaria appear to be similar to that seen in adults with uncomplicated malaria. Furthermore, as seen in adults, the mean total clearance and the volume of distribution of quinine were reduced in pediatric patients with malaria as compared to the healthy pediatric controls. Table 2 below provides a comparison of the mean ± SD pharmacokinetic parameters of quinine in pediatric patients vs. healthy pediatric controls. TABLE 2 Quinine Pharmacokinetic Parameters Following the First 10 mg/kg Quinine Sulfate Oral Dose in Healthy Pediatric Controls and Pediatric Patients with Acute Uncomplicated P. falciparum Malaria Healthy Pediatric Controls age 1.5 to 12 years ( N = 5 ) Mean ± SD P . falciparum Malaria Pediatric Patients ( N = 15 ) Mean ± SD T m a x (h) 2.0 4.0 C m a x (mcg/mL) 3.4 ± 1.18 7.5 ± 1.1 Half-life (h) 3.2 ± 0.3 12.1 ± 1.4 Total CL (L/h/kg) 0.30 ± 0.04 0.06 ± 0.01 Vd (L/kg) 1.43 ± 0.18 0.87 ± 0.12 Geriatric Patients: Following a single oral dose of 600 mg quinine sulfate, the mean AUC was about 38% higher in 8 healthy elderly subjects (65 to 78 years old) than in 12 younger subjects (20 to 35 years old). The mean T max and C max were similar in elderly and younger subjects after a single oral dose of quinine sulfate 600 mg. The mean oral clearance of quinine was significantly decreased, and the mean elimination half-life was significantly increased in elderly subjects compared with younger subjects (0.06 vs. 0.08 L/h/kg, and 18.4 hours vs. 10.5 hours, respectively). Although there was no significant difference in the renal clearance of quinine between the two age groups, elderly subjects excreted a larger proportion of the dose in urine as unchanged drug than younger subjects (16.6% vs. 11.2%). After a single 648 mg dose or at steady state, following quinine sulfate 648 mg given three times daily for 7 days, no d