pafuramidine pafuramidine pafuramidine (formulated as the maleic acid salt pafuramidine maleate) is an experimental drug for the treatment of pneumocystis pneumonia (pcp). in 2006, pafuramidine was given orphan drug status by the us food and drug administration for pcp in patients with hiv/aids. preliminary clinical trials indicated that pafuramide was effective against pneumocystis pneumonia and had the potential for fewer side effects than the standard treatment with trimethoprim/sulfamethoxazole (tmp-smx). pafuramidine names iupac name n′-methoxy-4-phenyl]furan-2-yl] benzenecarboximidamide other names db289 identifiers cas number 186953-56-0 y837369-26-3 (maleate) y 3d model (jsmol) interactive image chembl chembl319669 chemspider 4586633 pubchem cid 5480200 unii h1vg379j2x yk27f04k3a9 (maleate) y inchi inchi=1s/c20h20n4o3/c1-25-23-19(21)15-7-3-13(4-8-15)17-11-12-18(27-17)14-5-9-16(10-6-14)20(22)24-26-2/h3-12h,1-2h3,(h2,21,23)(h2,22,24)key: ukoqvlaxcbrrgh-uhfffaoysa-ninchi=1/c20h20n4o3/c1-25-23-19(21)15-7-3-13(4-8-15)17-11-12-18(27-17)14-5-9-16(10-6-14)20(22)24-26-2/h3-12h,1-2h3,(h2,21,23)(h2,22,24)key: ukoqvlaxcbrrgh-uhfffaoyae smiles co/n=c(\n)/c1=cc=c(c=c1)c2=cc=c(o2)c3=cc=c(c=c3)/c(=n/oc)/n properties chemical formula c20h20n4o3 molar mass 364.405 g·mol−1 pharmacology routes ofadministration oral legal status investigational except where otherwise noted, data are given for materials in their standard state (at 25 °c , 100 kpa). infobox references pafuramidine also reached phase iii clinical trials for the treatment of first stage african sleeping sickness, but development was halted in 2008 over concerns about kidney toxicity.