Comparative Pharmacology
Head-to-head clinical analysis: CHLOROQUINE PHOSPHATE versus MALARONE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CHLOROQUINE PHOSPHATE versus MALARONE.
CHLOROQUINE PHOSPHATE vs MALARONE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Chloroquine is a 4-aminoquinoline that acts as a blood schizonticide. It inhibits heme polymerase in malaria parasites, preventing the conversion of toxic heme to hemozoin, leading to accumulation of toxic heme and parasite death. It also has anti-inflammatory and immunomodulatory effects via inhibition of toll-like receptors and cytokine production.
Atovaquone is a selective inhibitor of the mitochondrial electron transport chain at the cytochrome bc1 complex (Complex III), disrupting pyrimidine synthesis and ATP generation in Plasmodium species. Proguanil, via its metabolite cycloguanil, inhibits dihydrofolate reductase (DHFR), blocking DNA synthesis. Synergistic activity against erythrocytic and exoerythrocytic stages.
600 mg base (1 g phosphate) orally once daily for 2 days, then 300 mg base (500 mg phosphate) orally once daily for 3 days for malaria. For extraintestinal amebiasis: 600 mg base (1 g phosphate) orally once daily for 2 days, then 300 mg base (500 mg phosphate) orally once daily for 2-3 weeks.
For malaria treatment: 4 tablets (each containing atovaquone 250 mg/proguanil 100 mg) orally once daily for 3 consecutive days. For malaria prophylaxis: 1 tablet (atovaquone 250 mg/proguanil 100 mg) orally once daily starting 1-2 days before travel, continued during travel and for 7 days after leaving endemic area.
None Documented
None Documented
Terminal elimination half-life: 30-60 days (range 20-100 days); prolonged due to extensive tissue distribution and slow release from lysosomes.
Atovaquone: 50-70 hours (mean ~60 h); proguanil: 12-21 hours (mean ~16 h); cycloguanil: 10-16 hours. Long half-life of atovaquone allows single-dose treatment, but may delay parasite clearance.
Renal: 50-70% as unchanged drug; hepatic/biliary: 20-30% as metabolites; fecal: up to 20%.
Atovaquone: 94% excreted unchanged in feces via biliary elimination, 6% in urine. Proguanil: 40-60% excreted unchanged in urine; cycloguanil (active metabolite) and proguanil metabolites also cleared renally.
Category C
Category C
Antimalarial
Antimalarial