Antimalarial activity of tripynadine in mice and monkeys

The antimalarial activity of tripynadine(M-7204), an analogue of pyronaridine, was evaluated and compared with that of pyronaridine. The ED50s of tripynadine and pyronaridine against Plasmodium berghei ANKA strain were 2.63 and 0.85 mg/kg daily×4 d, respectively. Bothtripynadine and pyronaridine exhibited no cross-resistance to ehloroquine, piperaquine and hydroxypiperaquine. The blood schizontocidal activity of tripynadine against P cynomolgi was comparable to that of pyronaridine. The residual activity of killing blood schizcnts lasted 5 d at the doses of 1.5 or 2.0×ED50 value, 20 d at that of 4.0×ED50 value with tripynadine, and 5 d at the dose of 2.0×ED50 value and 10 d at 4.0×ED50 value with pyronaridine.