Atovaquone and Proguanil Hydrochloride

MALARONE is an antimalarial indicated for:

• prophylaxis of Plasmodium falciparum (P. falciparum) malaria, including in areas where chloroquine resistance has been reported. ( 1.1 )
• treatment of acute, uncomplicated P. falciparum malaria. ( 1.2 )

1.1 Prevention of Malaria MALARONE is indicated for the prophylaxis of Plasmodium falciparum (P. falciparum) malaria, including in areas where chloroquine resistance has been reported.

1.2 Treatment of Malaria MALARONE is indicated for the treatment of acute, uncomplicated P. falciparum malaria. MALARONE has been shown to be effective in regions where the drugs chloroquine, halofantrine, mefloquine, and amodiaquine may have unacceptable failure rates, presumably due to drug resistance.

Each MALARONE tablet (adult strength) contains 250 mg atovaquone and 100 mg proguanil hydrochloride. MALARONE tablets are pink, film‑coated, round, biconvex tablets engraved with “GX CM3” on one side. Each MALARONE pediatric tablet contains 62.5 mg atovaquone and 25 mg proguanil hydrochloride. MALARONE pediatric tablets are pink, film‑coated, round, biconvex tablets engraved with “GX CG7” on one side.

• Tablets (adult strength): 250 mg atovaquone and 100 mg proguanil hydrochloride. ( 3 )
• Pediatric tablets: 62.5 mg atovaquone and 25 mg proguanil hydrochloride. ( 3 )

• MALARONE is contraindicated in individuals with known hypersensitivity reactions to atovaquone or proguanil hydrochloride or any component of the formulation [see Warnings and Precautions ( 5.4 ), Adverse Reactions ( 6.2 )] .
• MALARONE is contraindicated for prophylaxis of P. falciparum malaria in patients with severe renal impairment (creatinine clearance <30 mL/min) because of pancytopenia in patients with severe renal impairment treated with proguanil [see Use in Specific Populations ( 8.6 ), Clinical Pharmacology ( 12.3 )] .
• Known serious hypersensitivity reactions to atovaquone or proguanil hydrochloride or any component of the formulation. ( 4 )
• Prophylaxis of P. falciparum malaria in patients with severe renal impairment (creatinine clearance <30 mL/min). ( 4 )

• Atovaquone absorption may be reduced in patients with diarrhea or vomiting. If used in patients who are vomiting, parasitemia should be closely monitored and the use of an antiemetic considered. In patients with severe or persistent diarrhea or vomiting, alternative antimalarial therapy may be required. ( 5.1 )
• In mixed P. falciparum and Plasmodium vivax (P. vivax) infection, P. vivax relapse occurred commonly when patients were treated with MALARONE alone. ( 5.2 )
• In the event of recrudescent P. falciparum infections after treatment or prophylaxis failure, patients should be treated with a different blood schizonticide. ( 5.2 )
• Elevated liver laboratory tests and cases of hepatitis and hepatic failure requiring liver transplantation have been reported with prophylactic use. ( 5.3 )
• Severe Cutaneous Adverse Reactions (SCARs): Cases of SCARs such as Stevens‑Johnson syndrome (SJS) have been reported. SCARs can be life‑threatening or fatal. If symptoms or signs of SCARs develop, discontinue MALARONE immediately and institute appropriate therapy. ( 5.4 )
• MALARONE has not been evaluated for the treatment of cerebral malaria or other severe manifestations of complicated malaria. Patients with severe malaria are not candidates for oral therapy. ( 5.5 )

5.1 Vomiting and Diarrhea Absorption of atovaquone may be reduced in patients with diarrhea or vomiting. If MALARONE is used in patients who are vomiting, parasitemia should be closely monitored and the use of an antiemetic considered. [See Dosage and Administration ( 2 ).] Vomiting occurred in up to 19% of pediatric patients given treatment doses of MALARONE. In the controlled clinical trials, 15.3% of adults received an antiemetic when they received atovaquone/proguanil and 98.3% of these patients were successfully treated. In patients with severe or persistent diarrhea or vomiting, alternative antimalarial therapy may be required.

5.2 Relapse of Infection In mixed P. falciparum and Plasmodium vivax (P. vivax) infections, P. vivax parasite relapse occurred commonly when patients were treated with MALARONE alone. In the event of recrudescent P. falciparum infections after treatment with MALARONE or failure of chemoprophylaxis with MALARONE, patients should be treated with a different blood schizonticide.

5.3 Hepatotoxicity Elevated liver laboratory tests and cases of hepatitis and hepatic failure requiring liver transplantation have been reported with prophylactic use of MALARONE.

5.4 Severe Cutaneous Adverse Reactions Cases of severe cutaneous adverse reactions (SCARs), including Stevens ‑ Johnson syndrome (SJS), drug reaction with eosinophilia and systemic symptoms (DRESS), and erythema multiforme (EM) have been reported in patients treated with MALARONE [see Adverse Reactions ( 6.2 )]. SCARs can be life ‑ threatening or fatal. If symptoms or signs of SCARs develop, discontinue MALARONE immediately and institute appropriate therapy. Patients who have developed SCARs with the use of MALARONE must not receive MALARONE [see Contraindications ( 4 )].

5.5 Severe or Complicated Malaria MALARONE has not been evaluated for the treatment of cerebral malaria or other severe manifestations of complicated malaria, including hyperparasitemia, pulmonary edema, or renal failure. Patients with severe malaria are not candidates for oral therapy.

The following clinically significant adverse reactions are discussed in another section of the labeling:

• Vomiting and Diarrhea [see Warnings and Precautions ( 5.1 )].
• Hepatotoxicity [see Warnings and Precautions ( 5.3 )].
• Severe Cutaneous Adverse Reactions [see Warnings and Precautions ( 5.4 )].
• Prophylaxis: Common adverse reactions (≥4%) in adults were diarrhea, dreams, oral ulcers, and headache; these events occurred in a similar or lower proportion of subjects receiving MALARONE than an active comparator. Common adverse reactions (≥5%) in pediatric patients included abdominal pain, headache, cough, and vomiting. ( 6.1 )
• Treatment: Common adverse reactions (≥5%) in adolescents and adults were abdominal pain, nausea, vomiting, headache, diarrhea, asthenia, anorexia, and dizziness. Common adverse reactions (≥6%) in pediatric patients included vomiting, pruritus, and diarrhea. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact GlaxoSmithKline at 1-888-825-5249 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch .

6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared with rates in the clinical trials of another drug and may not reflect the rates observed in practice. Because MALARONE contains atovaquone and proguanil hydrochloride, the type and severity of adverse reactions associated with each of the compounds may be expected. The lower prophylactic doses of MALARONE were better tolerated than the higher treatment doses. Prophylaxis of P. falciparum Malaria In 3 clinical trials (2 of which were placebo‑controlled) 381 adults (mean age: 31 years) received MALARONE for the prophylaxis of malaria; the majority of adults were black (90%) and 79% were male. In a clinical trial for the prophylaxis of malaria, 125 pediatric patients (mean age: 9 years) received MALARONE; all subjects were black and 52% were male. Adverse experiences reported in adults and pediatric patients considered attributable to therapy occurred in similar proportions of subjects receiving MALARONE or placebo in all studies. Prophylaxis with MALARONE was discontinued prematurely due to a treatment‑related adverse experience in 3 of 381 (0.8%) adults and 0 of 125 pediatric patients. In a placebo‑controlled study of malaria prophylaxis with MALARONE involving 330 pediatric patients (aged 4 to 14 years) in Gabon, a malaria‑endemic area, the safety profile of MALARONE was consistent with that observed in the earlier prophylactic studies in adults and pediatric patients. The most common treatment‑emergent adverse events with MALARONE were abdominal pain (13%), headache (13%), and cough (10%). Abdominal pain (13% vs. 8%) and vomiting (5% vs. 3%) were reported more often with MALARONE than with placebo. No patient withdrew from the study due to an adverse experience with MALARONE. No routine laboratory data were obtained during this study. Non‑immune travelers visiting a malaria‑endemic area received MALARONE (n = 1,004) for prophylaxis of malaria in 2 active-controlled clinical trials. In one study (n = 493), the mean age of subjects was 33 years and 53% were male; 90% of subjects were white, 6% of subjects were black, and the remaining were of other racial/ethnic groups. In the other study (n = 511), the mean age of subjects was 36 years and 51% were female; the majority of subjects (97%) were white. Adverse experiences occurred in a similar or lower proportion of subjects receiving MALARONE than an active comparator ( Table 3 ). Fewer neuropsychiatric adverse experiences occurred in subjects who received MALARONE than mefloquine. Fewer gastrointestinal adverse experiences occurred in subjects receiving MALARONE than chloroquine/proguanil. Compared with active comparator drugs, subjects receiving MALARONE had fewer adverse experiences overall that were attributed to prophylactic therapy ( Table 3 ). Prophylaxis with MALARONE was discontinued prematurely due to a treatment‑related adverse experience in 7 of 1,004 travelers. Table 3. Adverse Reactions in Active-Controlled Clinical Trials of MALARONE for Prophylaxis of P. falciparum Malaria a Adverse experiences that started while receiving active study drug. b Mean duration of dosing based on recommended dosing regimens. Adverse Experience Percent of Subjects with Adverse Experiences a (Percent of Subjects with Adverse Experiences Attributable to Therapy) Study 1 Study 2 MALARONE n = 493 (28 days) b Mefloquine n = 483 (53 days) b MALARONE n = 511 (26 days) b Chloroquine plus Proguanil n = 511 (49 days) b Diarrhea 38 (8) 36 (7) 34 (5) 39 (7) Nausea 14 (3) 20 (8) 11 (2) 18 (7) Abdominal pain 17 (5) 16 (5) 14 (3) 22 (6) Headache 12 (4) 17 (7) 12 (4) 14 (4) Dreams 7 (7) 16 (14) 6 (4) 7 (3) Insomnia 5 (3) 16 (13) 4 (2) 5 (2) Fever 9 (<1) 11 (1) 8 (<1) 8 (<1) Dizziness 5 (2) 14 (9) 7 (3) 8 (4) Vomiting 8 (1) 10 (2) 8 (0) 14 (2) Oral ulcers 9 (6) 6 (4) 5 (4) 7 (5) Pruritus 4 (2) 5 (2) 3 (1) 2 (<1) Visual difficulties 2 (2) 5 (3) 3 (2) 3 (2) Depression <1 (<1) 5 (4) <1 (<1) 1 (<1) Anxiety 1 (<1) 5 (4) <1 (<1) 1 (<1) Any adverse experience 64 (30) 69 (42) 58 (22) 66 (28) Any neuropsychiatric event 20 (14) 37 (29) 16 (10) 20 (10) Any GI event 49 (16) 50 (19) 43 (12) 54 (20) In a third active‑controlled study, MALARONE (n = 110) was compared with chloroquine/proguanil (n = 111) for the prophylaxis of malaria in 221 non-immune pediatric patients (aged 2 to 17 years). The mean duration of exposure was 23 days for MALARONE, 46 days for chloroquine, and 43 days for proguanil, reflecting the different recommended dosage regimens for these products. Fewer patients treated with MALARONE reported abdominal pain (2% vs. 7%) or nausea (<1% vs. 7%) than children who received chloroquine/proguanil. Oral ulceration (2% vs. 2%), vivid dreams (2% vs. <1%), and blurred vision (0% vs. 2%) occurred in similar proportions of patients receiving either MALARONE or chloroquine/proguanil, respectively. Two patients discontinued prophylaxis with chloroquine/proguanil due to adverse events, while none of those receiving MALARONE discontinued due to adverse events. Treatment of Acute, Uncomplicated P. falciparum Malaria In 7 controlled trials, 436 adolescents and adults received MALARONE for treatment of acute, uncomplicated P. falciparum malaria. The range of mean ages of subjects was 26 to 29 years; 79% of subjects were male. In these studies, 48% of subjects were classified as other racial/ethnic groups, primarily Asian; 42% of subjects were black and the remaining subjects were white. Attributable adverse experiences that occurred in ≥5% of patients were abdominal pain (17%), nausea (12%), vomiting (12%), headache (10%), diarrhea (8%), asthenia (8%), anorexia (5%), and dizziness (5%). Treatment was discontinued prematurely due to an adverse experience in 4 of 436 (0.9%) adolescents and adults treated with MALARONE. In 2 controlled trials, 116 pediatric patients (weighing 11 to 40 kg) (mean age: 7 years) received MALARONE for the treatment of malaria. The majority of subjects were black (72%); 28% were of other racial/ethnic groups, primarily Asian. Attributable adverse experiences that occurred in ≥5% of patients were vomiting (10%) and pruritus (6%). Vomiting occurred in 43 of 319 (13%) pediatric patients who did not have symptomatic malaria but were given treatment doses of MALARONE for 3 days in a clinical trial. The design of this clinical trial required that any patient who vomited be withdrawn from the trial. Among pediatric patients with symptomatic malaria treated with MALARONE, treatment was discontinued prematurely due to an adverse experience in 1 of 116 (0.9%). In a study of 100 pediatric patients (5 to <11 kg body weight) who received MALARONE for the treatment of uncomplicated P. falciparum malaria, only diarrhea (6%) occurred in ≥5% of patients as an adverse experience attributable to MALARONE. […]

• Administration with rifampin or rifabutin is known to reduce atovaquone concentrations; concomitant use with MALARONE is not recommended. ( 7.1 )
• Proguanil may potentiate anticoagulant effect of warfarin and other coumarin-based anticoagulants. Caution advised when initiating or withdrawing MALARONE in patients on anticoagulants; coagulation tests should be closely monitored. ( 7.2 )
• Tetracycline may reduce atovaquone concentrations; parasitemia should be closely monitored. ( 7.3 )

7.1 Rifampin/Rifabutin Concomitant administration of rifampin or rifabutin is known to reduce atovaquone concentrations [see Clinical Pharmacology ( 12.3 )] . The concomitant administration of MALARONE and rifampin or rifabutin is not recommended.

7.2 Anticoagulants Proguanil may potentiate the anticoagulant effect of warfarin and other coumarin-based anticoagulants. The mechanism of this potential drug interaction has not been established. Caution is advised when initiating or withdrawing malaria prophylaxis or treatment with MALARONE in patients on continuous treatment with coumarin-based anticoagulants. When these products are administered concomitantly, coagulation tests should be closely monitored.

7.3 Tetracycline Concomitant treatment with tetracycline has been associated with a reduction in plasma concentrations of atovaquone [see Clinical Pharmacology ( 12.3 )] . Parasitemia should be closely monitored in patients receiving tetracycline.

7.4 Metoclopramide While antiemetics may be indicated for patients receiving MALARONE, metoclopramide may reduce the bioavailability of atovaquone and should be used only if other antiemetics are not available [see Clinical Pharmacology ( 12.3 )] .

7.5 Indinavir Concomitant administration of atovaquone and indinavir did not result in any change in the steady‑state AUC and C max of indinavir but resulted in a decrease in the C trough of indinavir [see Clinical Pharmacology ( 12.3 )] . Caution should be exercised when prescribing atovaquone with indinavir due to the decrease in trough concentrations of indinavir.

Renal impairment: contraindicated for prophylaxis of P. falciparum malaria in patients with severe renal impairment. ( 8.6 )

8.1 Pregnancy Risk Summary Available data from published literature and postmarketing experience with use of MALARONE in pregnant women are insufficient to identify a drug-associated risk for major birth defects, miscarriage, or adverse maternal or fetal outcomes . The proguanil component of MALARONE acts to inhibit parasitic dihydrofolate reductase; however, pregnant women and females of reproductive potential should continue folate supplementation to prevent neural tube defects [see Clinical Pharmacology ( 12.4 )] . Pregnant women with malaria are at increased risk for adverse pregnancy outcomes (see Clinical Considerations). Atovaquone administered by oral gavage to pregnant rats and rabbits during the period of organogenesis was not associated with fetal malformations at plasma exposures approximately 7 times and equal to, respectively, the estimated human exposure for the treatment of malaria based on AUC. Proguanil administered to pregnant rats and rabbits during the period of organogenesis was not associated with embryo-fetal toxicity at maternally toxic plasma exposures approximately 0.07 and 0.8 times, respectively, the estimated human exposure for treatment of malaria based on AUC (see Data) . The combination of atovaquone and proguanil hydrochloride given orally by gavage during the period of organogenesis was not associated with embryo-fetal developmental effects in pregnant rats or rabbits at atovaquone:proguanil hydrochloride doses of 50:20 mg/kg/day and 100:40 mg/kg/day, respectively (1.7 and 0.1 times and 0.3 and 0.5 times, respectively, the estimated human exposure for treatment of malaria). In a pre- and post-natal study with atovaquone and another pre-and post-natal study with proguanil, neither compound impaired the growth, development, or reproductive ability of first-generation offspring at maternal AUC exposures of approximately 7.3 and 0.04 times, respectively, the estimated human AUC exposure for treatment of malaria (see Data) . The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Clinical Considerations Disease-Associated Maternal and/or Embryo/Fetal Risk: Malaria during pregnancy increases the risk for adverse pregnancy outcomes, including maternal anemia, prematurity, spontaneous abortion, and stillbirth. Data Animal Data: Atovaquone: Atovaquone administered in oral doses of 250, 500, and 1,000 mg/kg/day during organogenesis (Gestation Day [GD] 6 to GD15) in pregnant rats did not cause maternal or embryo-fetal toxicity at doses up to 1,000 mg/kg/day corresponding to maternal plasma exposures up to 7.3 times the estimated human exposure for the treatment of malaria based on AUC. In pregnant rabbits, atovaquone administered in oral doses of 300, 600, and 1,200 mg/kg/day by gavage during organogenesis (GD6 to GD18) was associated with decreased fetal body length at a maternally toxic dose of 1,200 mg/kg/day corresponding to plasma exposures that were approximately 1.3 times the estimated human exposure during treatment of malaria based on AUC. In a pre- and post-natal study in rats, atovaquone administered in oral doses of 250, 500, and 1,000 mg/kg/day from GD15 until Lactation Day (LD) 20 did not impair the growth or developmental effects in first-generation offspring at doses up to 1,000 mg/kg/day corresponding to AUC exposures of approximately 7.3 times the estimated human exposure during treatment of malaria. Atovaquone crossed the placenta and was present in fetal rat and rabbit tissue. Proguanil: Proguanil administered orally to pregnant rats during organogenesis (GD6 to GD17) was not associated with fetal malformations, but increased ureter variations at a maternally toxic dose of 20 mg/kg/day corresponding to a plasma concentration approximately equal to 0.07 times the estimated human exposure for the treatment of malaria based on AUC. Proguanil given orally by gavage at a maternally toxic dose of 40 mg/kg/day to pregnant rabbits during organogenesis (GD6 to GD20) did not produce adverse embryo-fetal effects at a plasma concentration up to 0.8 times the estimated human exposure for the treatment of malaria based on AUC. In a pre- and post-natal study in female rats, proguanil hydrochloride administered in oral doses of 4, 8, or 16 mg/kg/day from GD6 until LD20 did not impair the growth, development, or reproductive ability of first-generation offspring or the survivability of second generation offspring at doses up to 16 mg/kg/day (0.04 times the average human exposure based on AUC). Pre- and post-natal studies of proguanil in animals at exposures similar to or greater than those observed in humans have not been conducted. Atovaquone and Proguanil: The combination of atovaquone and proguanil hydrochloride administered orally to pregnant rats in atovaquone:proguanil hydrochloride doses of 12.5:5, 25:10, and 50:20 mg/kg/day during organogenesis (GD6 to GD17) did not produce maternal toxicity or adverse embryo-fetal developmental effects with doses up to 50:20 mg/kg/day corresponding to plasma concentrations up to 1.7 and 0.1 times, respectively, the estimated human exposure during treatment of malaria based on AUC. In pregnant rabbits, the combination of atovaquone and proguanil hydrochloride administered orally in atovaquone:proguanil hydrochloride doses of 25:10, 50:20, or 100:40 mg/kg/day during organogenesis (GD6 to GD20) did not produce adverse embryo-fetal developmental effects at a maternally toxic dose of 100:40 mg/kg/day corresponding to plasma concentrations of approximately 0.3 and 0.5 times, respectively, the estimated human exposure during treatment of malaria based on AUC.

8.2 Lactation Risk Summary There are no data on the presence of atovaquone in human milk; however, proguanil is present in human milk. Atovaquone is present in rat milk (see Data) . When a drug is present in animal milk, it is likely the drug will be present in human milk. There are no data on the effects of atovaquone and proguanil on the breastfed child or the effects on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for MALARONE and any potential adverse effect on the breastfed child from MALARONE or from the underlying maternal condition. Data In a rat study with doses of 10 and 250 mg/kg, given orally by gavage on postpartum Day 11, atovaquone concentrations in the milk were 30% of the concurrent atovaquone concentrations in the maternal plasma at both doses. The concentration of drug in animal milk does not necessarily predict the concentration of drug in human milk.

8.4 Pediatric Use Prophylaxis of Malaria Safety and effectiveness have not been established in pediatric patients who weigh less than 11 kg. The efficacy and safety of MALARONE have been established for the prophylaxis of malaria in controlled trials involving pediatric patients weighing 11 kg or more [see Clinical Studies ( 14.1 )] . Treatment of Malaria Safety and effectiveness have not been established in pediatric patients who weigh less than 5 kg. The efficacy and safety of MALARONE for the treatment of malaria have been established in controlled trials involving pediatric patients weighing 5 kg or more [see Clinical Studies ( 14.2 )] .

8.5 Geriatric Use Clinical trials of MALARONE did not include sufficient numbers of subjects aged 65 years and older to determine whether they respond differently from younger subjects. […]

MALARONE, a fixed-dose combination of atovaquone and proguanil hydrochloride, is an antimalarial agent [see Microbiology ( 12.4 )] .