Extended blood stage sensitivity profiles of Plasmodium cynomolgi to doxycycline and tafenoquine, as a model for Plasmodium vivax

Antimicrob Agents Chemother. 2024 May 2;68(5):e0028024. doi: 10.1128/aac.00280-24. Epub 2024 Apr 8.

Abstract

Testing Plasmodium vivax antimicrobial sensitivity is limited to ex vivo schizont maturation assays, which preclude determining the IC50s of delayed action antimalarials such as doxycycline. Using Plasmodium cynomolgi as a model for P. vivax, we determined the physiologically significant delayed death effect induced by doxycycline [IC50(96 h), 1,401 ± 607 nM]. As expected, IC50(96 h) to chloroquine (20.4 nM), piperaquine (12.6 µM), and tafenoquine (1,424 nM) were not affected by extended exposure.

Keywords: Plasmodium cynomolgi; Plasmodium vivax; antimalarial agents; chloroquine; doxycycline; tafenoquine.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, N.I.H., Extramural

MeSH terms

  • Aminoquinolines* / pharmacology
  • Animals
  • Antimalarials* / pharmacology
  • Chloroquine / pharmacology
  • Doxycycline* / pharmacology
  • Humans
  • Inhibitory Concentration 50
  • Malaria, Vivax / drug therapy
  • Malaria, Vivax / parasitology
  • Parasitic Sensitivity Tests
  • Piperazines*
  • Plasmodium cynomolgi* / drug effects
  • Plasmodium vivax* / drug effects
  • Quinolines / pharmacology

Substances

  • tafenoquine
  • Doxycycline
  • Antimalarials
  • Aminoquinolines
  • Chloroquine
  • piperaquine
  • Quinolines
  • Piperazines