DHFR and cryptosporidiosis: However, MMV675968 (cryptosporidiosis set), a structurally related diaminoquinazoline, has potent activity against the asexual stage of P. falciparum (3D7 IC50, 0.03 μM; SI HEK, 7.4; SI HepG2, 113), and DHFR has been shown to be the cellular target (92).