NCIt definition : A synthetic derivative of ethyl-pyrimidine with potent antimalarial properties. Pyrimethamine
is a competitive inhibitor of dihydrofolate reductase (DHFR). DHFR is a key enzyme
in the redox cycle for production of tetrahydrofolate, a cofactor that is required
for the synthesis of DNA and proteins. This agent is often used in combination with
other antimalarials for the treatment of uncomplicated falciparum malaria. (NCI04);