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Plasmodium Falciparum Clearance Rates in Response to Artesunate in Eastern Cambodia

NCT01240603 · Status: COMPLETED · Type: OBSERVATIONAL · Enrollment: 415

Last updated 2018-04-05

No results posted yet for this study

Summary

Plasmodium falciparum parasite clearance rates (PCRs) after oral artesunate treatment of patients with uncomplicated malaria were recently found to be significantly slower in Pailin (Western Cambodia) compared to Wang Pha (Eastern Thailand). This difference in PCRs has been attributed to different histories of artesunate drug pressure in the two areas. In Pailin, artesunate monotherapy has been used inappropriately for 30 years and is hypothesized to have selected for artemisinin-resistant parasites (slow PCRs). To investigate the potential contribution of human factors to the artemisinin resistance phenotype, we have identified a study site in Eastern Cambodia where artemisinin-resistant parasites are not believed to be present. The main aims of this study are to 1) determine whether the artemisinin resistance phenotype (i.e., a half-life longer than the 2-hour half-life observed in Wang Pha) is present in Eastern Cambodia, 2) determine whether hemoglobin E affects parasite clearance rates in vivo, 3) determine whether age-associated acquired immunity affects parasite clearance rates in vivo, and 4) identify parasite-heritable traits that are associated with slow parasite clearance rates in vivo. To meet these aims, we are conducting a prospective, longitudinal study to recruit Cambodian residents of Lumphat District in Ratanakiri Province who complain of fever and/or symptoms of malaria. Patients diagnosed with uncomplicated malaria will be treated with weight-based doses of artesunate given orally each day for 3 days followed by mefloquine given orally for 2 days. During this time, finger prick blood smears will be obtained every 6 hours until parasite density is zero. From these data, we will estimate parasite clearance rates using a half-life parameter. We will also collect parasitized red blood cell samples from malaria patients prior to antimalarial drug administration. These parasites will be tested in short-term in vitro culture experiments to determine their susceptibility to artemisinins and other antimalarial drugs.

Conditions

Sponsors & Collaborators

  • National Centre for Parasitology, Entomology and Malaria Control, Cambodia

    collaborator OTHER

  • National Institute of Allergy and Infectious Diseases (NIAID)

    lead NIH

Principal Investigators

  • Rick M Fairhurst, M.D. · National Institute of Allergy and Infectious Diseases (NIAID)

Eligibility

Min Age
1 Year
Sex
ALL
Healthy Volunteers
No

Timeline & Regulatory

Start
2010-10-24
Completion
2013-09-11

Countries

  • Cambodia

Study Locations

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Entities

Diseases

Read the full study record

This page highlights key information. For complete eligibility criteria, study locations, investigator contacts, and the full protocol, visit the original record on ClinicalTrials.gov.

View NCT01240603 on ClinicalTrials.gov