Eflornithine

Class: 

Eflornithine, (DL-alpha-difluoromethylornithine) is a fluorinated analogue of the uncommon amino acid ornithine.

Antiparasitic Activity:

Eflornithine is highly effective against Trypanosoma brucei gambiense and, when available, is the drug of choice in late-stage Gambian human African trypanosomiasis. Eflornithine is not effective against Trypanosoma brucei rhodesiense.

Mechanisms of Action:

Eflornithine is an irreversible suicide inhibitor of ornithine decarboxylase, the first enzyme in the biosynthesis of the polyamines putrescine and spermidine.

Mechanisms of Resistance:

The mechanisms of eflornithine resistance for T.b. gambiense have not yet been elucidated.

Pharmacokinetics:

 Eflornithine is about 50% orally bioavailable. Its elimination half-life is 3.3 h and 81% is excreted unchanged.

Dosage:

The recommended dosage for new cases of late-stage Gambian trypanosomiasis is 100 mg/kg every 6h IV for 14 days.

Reduce dosage in renal failure.

Adverse Effects:

Hematological: anemia (up to 40%), leukopenia (20-30%) or thrombocytopenia (50%).

Seizures associated with high CSF concentrations

Diarrhea (12% IV, 50% po)

Abortion in pregnant women

Pregnancy:

Studies with eflornithine have not been done in pregnant women.

Drug Interactions:

No data.

Brand names/Manufacturer:

Ornidyl™ (Aventis)