Comparison of Two Antimalarial Drugs Regimens in Patient With Plasmodium Vivax Malaria in Thailand

• Status: Unknown status
• Trial end date: 2014-12-01
• Target enrollment: 0
• Participant gender: All

Summary

In Thailand, the proportion of P.vivax infection has now been increasing and is equal to Plasmodium falciparum since 1998. The incidence of P.vivax has recently been reported as 20 per 1000 population per year. Unlike Plasmodium falciparum, P.vivax infection rarely develops into complicated malaria and death is unusual. However, P.vivax has a dormant stage (the hypnozoite) that persists in the human liver and may cause relapse weeks, months, or even years later. Therefore, P.vivax infection is considered to have greater impact on morbidity than mortality, resulting in significant social and economic burden. Moreover, it is very difficult to control P.vivax transmission, because gametocytes appear almost simultaneously with schizonts.

Radical treatment of the infection, therefore, normally consists of a blood schizontocidal course of chloroquine and a course primaquine for the elimination of the hypnozoites as anti-relapse therapy. In Thailand, chloroquine and primaquine have remained the mainstay chemotherapeutics for the treatment of P.vivax for more than 60 years and resistance has not yet been reported . The relapse rates at day 28 are about 50% without primaquine therapy and about 20% with standard primaquine therapy. Relapse has not been observed among patients receiving high dose primaquine therapy (30 mg daily for 14 days).

Since January 2007, the evidence of reduced susceptibility of Plasmodium falciparum to artemisinins in Western Cambodia at Thai-Cambodia border was first presented and confirmed in a subsequent detailed pharmacokinetic-pharmacodynamic study. Nevertheless, a trend of gradual decline of in vitro sensitivity to chloroquine has been documented in some areas of the country, particularly Thai-Myanmar border. There has been no clinical-parasitological evidence of chloroquine resistant P.vivax in Thai-Cambodia border, Thailand.

The objectives of the present study are to assess in vivo efficacy of first line regimen of chloroquine given with primaquine, and in vitro susceptibility of P.vivax isolates in areas along Thai-Cambodia border, Thailand.

• Phase: Phase 4
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: Mahidol University
• Treatments: Antimalarials; Artesunate; Chloroquine; Chloroquine diphosphate; Primaquine

Criteria

Inclusion Criteria:

• Male or female, aged from 18 years to 65 years old who can come to the study hospital for follow up in case of re-infection

• Acute uncomplicated malaria with P.vivax infection, confirmed by positive blood smear with asexual forms of P. vivax with parasitaemia > 1,000 parasites/microliters

• Fever defined as temperature > 37.5 degree celsius or a history of fever within the last 24 hours

• Written informed consent

• Willingness and ability of the patients/guardians to comply with the study protocol for the duration of the study

• Communicate with Thai language

Exclusion Criteria:

• Mixed infection with other plasmodium species

• For females: pregnancy, breast feeding

• History of allergy or known contraindication to chloroquine, artesunate or primaquine

• Any criteria of severe / complicated malaria (WHO 2010)

• Presence of febrile condition caused by disease other than malaria.