Eflornithine (Molecule of the Month for July 2007)
Ornidyl,Vaniqa, Difluoromethylornithin, DFMO
Eflornithine is a drug which was initially developed as a cancer medication. Eflornithine appears to kill trypanosomes by acting as a suicide inhibitor of the enzyme ornithine decarboxylase, this enzyme regulates cell division by catalysing the first step in polyamine biosynthesis. Supplies of eflornithine are limited as its manufacturer does not consider it cost effective. Its production was halted by its manufacturer, Aventis, in 1995 because the company did not consider it a profitable drug.
It was also found to be very effective in combatting African trypanosomiasis (sleeping sickness), in its West African form (Trypanosoma brucei gambiense). Eflornithine's effects against Trypanosoma brucei gambiense were discovered by chance and because its ability to bring patients back from coma, it became known as "Resurrection Drug". It is hoped that eflornithine will replace the relatively toxic melarsoprol. In 2001, after heavy lobbying by Médecins Sans Frontières ("Doctors Without Borders"), the international medical NGO, and the World Health Organization (WHO), the manufacturer agreed to resume production of eflornithine, melarsoprol and pentamidine, in sufficient amounts to cover existing needs. This 5-year agreement with the WHO also envisaged MSF working on the distribution of the drugs. The yearly value of the drugs donated by Aventis under this agreement is US$5 million. In addition, under the agreement, Bristol-Myers Squibb, the manufacturer of Vaniqa, will pay for part of the eflornithine. The 5-year agreement expired in 2006.
Eflornithine is also an effective hair growth inhibiting agent. As a topical application, the drug has been shown to be an effective hair growth retardant in some patients, and is sold under the brand name Vaniqa. It is partly the development of the hair removal market that encouraged Aventis to re-start the manufacture of eflornithine, and which allowed it to once again become available for use in sleeping sickness.
Formal Chemical Name (IUPAC)
Update by Karl Harrison
(Molecule of the Month for July 2007 )