Chloroquine-primaquine therapeutic response and safety in patients with uncomplicated Plasmodium vivax malaria in the Colombian Amazon region.

Background: In Colombia, published studies on the treatment of uncomplicated Plasmodium vivax malaria with chloroquine-primaquine are scarce. The aim of this study was to evaluate the therapeutic response to two treatment regimens at the 28-day follow-up and the occurrence of adverse events in patients with P. vivax malaria.

Methods: A quasi-experimental clinical trial was conducted at 3 sites in the Department of Amazonas. Patients received supervised or unsupervised anti-malarial treatment (chloroquine plus primaquine), and the primary effectiveness endpoint was the clinical and parasitological response. Safety was assessed through adverse event surveillance.

Results: A total of 103 patients were included: 53 in the 7-day primaquine group (Group I) and 50 in the group receiving primaquine for 14 days (Group II). Among the patients in group I, an adequate treatment response of 100% and 89.5% was found in patients who received supervised and unsupervised treatment, respectively. In Group II, adequate responses of 100% and 95% were reported for patients who received supervised and unsupervised treatment, respectively. No adverse events were detected.

Conclusions: The response to combined treatment with chloroquine plus primaquine continues to be adequate for treating P. vivax malaria in the Colombian Amazon region; however, a response to unsupervised treatment in the region is recommended.