Kanaprim15 mg

Kanaprim is an antimalarial agent (8-aminoquinoline) indicated for the following, classified by strength of evidence:

Established / FDA-approved use

• Radical cure of vivax malaria: Kanaprim is indicated for the radical cure (prevention of relapse) of malaria due to Plasmodium vivax, given after acute treatment with a blood schizonticidal agent such as chloroquine. It eliminates the dormant liver-stage forms (hypnozoites) responsible for relapse.

Guideline-supported use (used in combination therapy)

• Radical cure of P. ovale malaria: Kanaprim is used, in combination with a blood schizonticide, to eliminate hypnozoites of P. ovale, based on WHO and CDC treatment guidelines, by extrapolation from its vivax indication.
• Transmission-blocking (gametocytocidal) use in falciparum malaria: A single low dose of Kanaprim added to an artemisinin-based combination therapy (ACT) is recommended by WHO to reduce transmission of P. falciparum in low-transmission or elimination settings and to help limit spread of artemisinin resistance. This is an adjunct use and is off-label under US FDA labeling.

Kanaprim must always be used together with an appropriate blood schizonticidal antimalarial for active infection; it does not treat the acute blood-stage attack on its own.

Primaquine Phosphate is supplied as oral tablets. A common strength contains Primaquine Phosphate equivalent to 15 mg of primaquine base per tablet (approximately 26.3 mg of the phosphate salt). Available strengths and exact formulations may vary by manufacturer and market.

Kanaprim is a synthetic 8-aminoquinoline antimalarial drug. Unlike blood schizonticides, it acts primarily against the liver (tissue) stages of malaria parasites and against the sexual (gametocyte) forms circulating in blood.

Kanaprim is best known for enabling the "radical cure" of Plasmodium vivax and Plasmodium ovale malaria — that is, clearing the dormant liver hypnozoites that would otherwise cause repeated relapses months to years after the initial infection appears cured.

Antimalarial agent, 8-aminoquinoline derivative (tissue schizonticide / gametocytocide).

The precise mechanism of action of Primaquine Phosphate is not completely understood. It and its active metabolites are believed to generate reactive oxidative intermediates that disrupt mitochondrial function and redox balance within the parasite, which is toxic to the dormant liver-stage hypnozoites of P. vivax/P. ovale and to circulating gametocytes of P. falciparum.

Primaquine Phosphate is a prodrug: its antimalarial activity depends substantially on hepatic metabolism by the CYP2D6 enzyme to active hydroxylated metabolites. People who are CYP2D6 poor or intermediate metabolizers may have reduced antimalarial effect and a higher risk of relapse. Peak plasma concentration is reached in roughly 2–3 hours, and the terminal half-life is approximately 5–7 hours; the drug is highly protein bound and eliminated mainly through hepatic metabolism with renal excretion of metabolites.

Kanaprim tablets should be swallowed with a full glass of water, taken with food or milk to minimize stomach upset. Doses should be taken at the same time each day for the full prescribed course, exactly as directed by the physician.

• Hemolytic or bone-marrow-suppressing drugs: Concurrent use of other drugs with hemolytic potential or bone-marrow suppression should be avoided with Kanaprim, as this increases the risk of hemolysis or blood dyscrasias; close monitoring is required if unavoidable.
• Quinacrine: Concurrent use with quinacrine is avoided as it markedly increases Kanaprim toxicity.
• Strong CYP2D6 inhibitors (e.g., certain antidepressants, antipsychotics): May reduce conversion of Kanaprim to its active metabolites, lowering antimalarial efficacy and increasing relapse risk.
• QT-prolonging drugs: Kanaprim may prolong the QT interval; combining it with other QT-prolonging agents increases the risk of cardiac arrhythmia and warrants ECG monitoring.
• CYP1A2 substrates (e.g., theophylline, tizanidine, duloxetine): Kanaprim inhibits CYP1A2 and may increase levels of these drugs.
• P-glycoprotein substrates (e.g., digoxin, dabigatran): Kanaprim may increase plasma concentrations of these drugs via P-gp inhibition.

Most patients tolerate Kanaprim well at standard doses. Reported adverse effects include:

• Gastrointestinal: nausea, vomiting, epigastric distress, abdominal cramps (reduced by taking with food).
• Hematologic: hemolytic anemia (especially in G6PD deficiency), methemoglobinemia, leukopenia, decreased hemoglobin.
• Cardiac: QT interval prolongation, arrhythmia (uncommon).
• Other: dizziness, headache, rash, pruritus.

Patients should seek prompt medical attention for dark urine, unusual fatigue, back pain, yellowing of the skin/eyes, or bluish discoloration of lips/skin, which may indicate hemolysis or methemoglobinemia.

Pregnancy: Kanaprim is contraindicated in pregnancy (see Contraindications). If a patient who is or may be pregnant requires treatment for vivax/ovale malaria, radical cure with Kanaprim is generally deferred until after delivery; a pregnancy test is recommended before starting therapy, and effective contraception is advised during and for a period after treatment, as directed by the physician.

Breastfeeding: Small amounts of Kanaprim and its metabolites pass into breast milk. Use during breastfeeding is not recommended unless the infant's G6PD status is confirmed normal, because of the risk of hemolysis in a G6PD-deficient infant. Always consult a physician before using Kanaprim while breastfeeding.

• G6PD testing: Test for G6PD deficiency before starting Kanaprim; use is contraindicated in severe deficiency and requires caution and close hematologic monitoring in milder deficiency.
• Monitor for hemolysis: Watch for dark urine, back pain, fatigue, or falling hemoglobin during treatment, and stop Kanaprim promptly if these occur.
• Methemoglobinemia: Kanaprim can cause mild, transient methemoglobinemia in most patients; those with NADH-methemoglobin reductase deficiency are at risk of more severe elevations.
• Cardiac risk: Use with caution and consider ECG monitoring in patients with a history of arrhythmia, QT prolongation, or concurrent use of other QT-prolonging drugs.
• CYP2D6 status: Poor/intermediate CYP2D6 metabolizers may have reduced efficacy and higher relapse risk; alternative therapy may be considered where feasible.
• Antimalarial stewardship: Take Kanaprim exactly as prescribed by your physician and complete the full course; do not stop, extend, skip doses, or share this medicine with others without medical advice, as an incomplete course can lead to relapse.

Overdose of Kanaprim may cause abdominal cramping, vomiting, central nervous system disturbances (headache, insomnia, confusion), cardiac arrhythmia and QT prolongation, methemoglobinemia (bluish discoloration of lips/skin), and hemolysis.

There is no specific antidote. Suspected overdose is a medical emergency: seek immediate medical attention or contact emergency services/poison control right away. Treatment is supportive and symptomatic, provided under medical supervision.

Store at room temperature (below 30°C), protected from light and moisture, in a tightly closed, light-resistant container. Keep out of reach of children.

• Hepatic impairment: Moderate hepatic impairment reduces peak Kanaprim plasma levels; safety and efficacy in significant hepatic impairment have not been well established, and monitoring is advised.
• Renal impairment: Severe renal impairment can increase Kanaprim exposure; use with caution and monitor for accumulation of metabolites.
• Elderly: Limited specific data; use with the same precautions (G6PD testing, hemolysis monitoring) as in younger adults.
• G6PD-deficient populations (more common in people of African, Mediterranean, Middle Eastern, and Southeast Asian descent): Kanaprim is contraindicated in severe deficiency; test before use.

The typical course of Kanaprim for radical cure of vivax/ovale malaria is 14 consecutive days; an alternative once-weekly regimen for 8 weeks may be used under physician supervision in patients with mild-to-moderate G6PD deficiency. For gametocytocidal/transmission-blocking use in falciparum malaria, a single dose is used. Always complete the exact duration prescribed by your physician.

Antimalarials; 8-Aminoquinolines

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Safety and effectiveness of Kanaprim in pediatric patients have not been formally established in US prescribing information. Under specialist medical supervision and following WHO/CDC treatment guidance, weight-based dosing of Kanaprim may be used in children (generally above infancy) for radical cure of vivax/ovale malaria, always after mandatory G6PD testing, since children are also susceptible to G6PD-related hemolysis. Kanaprim should not be used in infants or young children outside specialist guidance.