Antimalarial Drug Resistance in Mali

NCT ID: NCT00127998

Last Updated: 2006-08-16

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

COMPLETED

Clinical Phase

NA

Total Enrollment

1011 participants

Study Classification

INTERVENTIONAL

Study Start Date

2005-07-31

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

Resistance of Plasmodium falciparum (malaria) to current antimalarial drugs and the continuing development of resistance to new antimalarial formulations is one of the major obstacles to effective malaria control and case management. Efficient, comprehensive and validated methods for monitoring drug resistance in advance of the development of resistance to the antimalarial drugs that are in use are urgently needed. Molecular markers of genetic polymorphisms that give rise to resistant P. falciparum parasites and methods in population genetics for evaluating the data can be valuable tools for monitoring drug resistance in the field. This study aims to:

1. Prospectively measure the in vivo response of P. falciparum malaria in Mali to several different antimalarial drugs and drug combinations: chloroquine (CQ), sulfadoxine-pyrimethamine (SP), amodiaquine (AQ), sulfadoxine-pyrimethamine in combination with amodiaquine (SP/AQ), amodiaquine in combination with artesunate (AQ/AS), sulfadoxine-pyrimethamine in combination with artesunate (SP/AS), and artemether-lumefantrine (Co-artem). In one site with preliminary data showing a high rate of P. falciparum resistance to mefloquine (MQ), this drug will also be tested.
2. Measure the frequencies of molecular markers for antimalarial drug resistance, and examine how those results relate to the efficacy of these drugs in treating clinical malaria
3. Measure drug levels at 3 days and correlate with efficacy results.
4. Examine early clinical, parasitologic, and clinical predictors of late treatment failure.
5. Use the knowledge gained in Aims 1-3 to develop a molecular tool for a countrywide resistance surveillance system for antimalarial drugs.

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

Resistance of Plasmodium falciparum to current antimalarial drugs and the continuing development of resistance to new antimalarial formulations is one of the major obstacles to effective malaria control and case management. Parasite populations are highly resistant to chloroquine on an almost worldwide basis (Central America and Haiti being the exceptions) and resistance to the next line of treatment, SP, is widespread in Asia and large parts of East Africa and South America. SP is also now recommended for use as intermittent preventative treatment (IPT) in pregnancy, which adds to concerns about the development and spread of SP resistance. More expensive combination drug therapy using artesunate and other antimalarials in combination is increasingly being recommended in an effort to extend the useful life of drugs and to slow the spread of antimalarial drug resistance. In all likelihood, resistance will eventually emerge for any new single drug or combination formulation that we deploy in the field.

Given the above, efficient, comprehensive and validated methods for monitoring drug resistance in advance of the development of resistance to the antimalarial drugs that are in use are urgently needed. Such methods would help malaria control and prevention programs in guiding national treatment recommendations and policies. Integrating laboratory expertise, analytic methods based on population genetics, and more traditional methods of surveillance for anti-malarial drug resistance (e.g. in vivo drug efficacy studies) and networking with national and international partners will result in a multidisciplinary, geographically diverse team approach to assessing and monitoring drug resistant malaria, as well as developing and validating molecular methods. This type of effort will greatly assist in maximizing the useful life span of antimalarial drugs and in providing evidence-based guidance for drug policy decisions.

Specific Aims:

1. Prospectively measure the in vivo response of P. falciparum malaria in Mali to CQ, SP, AQ, SP/AQ in combination, AQ/artesunate (AS) in combination, SP/AS, and artemether-lumefantrine (Co-artem). In one site with preliminary data showing a high rate of P. falciparum resistance to MQ, MQ will also be tested.
2. Measure the frequencies of dihydrofolate reductase (dhfr), dihydropteroate synthetase (dhps), P. falciparum chloroquine resistance transporter (pfcrt) and P. falciparum multi-drug resistant (pfmdr 1) genotypes and establish their relationship with in vivo resistance to SP (dhfr and dhps), CQ, AQ, SP/AQ, AQ/AS, SP/AS, and MQ.
3. Measure drug levels at 3 days and correlate with in vivo efficacy results.
4. Examine early clinical, parasitologic, and clinical predictors of late treatment failure.
5. Use the knowledge gained in Aims 1-3 to develop a molecular tool for a countrywide resistance surveillance system for SP, AQ, and MQ.

Study Design:

The study will entail two consecutive years of prospective 28 day in vivo drug efficacy studies carried out during the rainy season in three different malaria transmission sites: Koro (rural town with 71% of resistance to MQ at a lower dose of 15 mg/kg), Pongono (rural town with little exposure to antimalarials) and Faladje (rural village with \> 30% of chloroquine resistance). Children aged 6-59 months with clinical symptoms consistent with malaria will be enrolled in the study after screening for fever (axillary temperature \>=37.5 C) and malaria asexual parasites identified by microscopic examination of thick blood films.

Blood spotted onto filter papers will be collected prior to treatment and during follow up. These filter paper samples will be used for the molecular detection of drug resistance-conferring gene polymorphisms as well as the HPLC detection and quantification of the respective drugs and their relevant metabolites. In vivo data interpretation will be done using the WHO 28-day protocol (WHO, 2003) and molecular markers will be used for the determination of the genotype resistance index (GRI). Venous blood will be collected at enrollment and at the time of in vivo failure to measure in vitro drug efficacy and cryopreserve parasites to search for novel molecular markers to new antimalarial drugs.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Malaria

Keywords

Explore important study keywords that can help with search, categorization, and topic discovery.

malaria Plasmodium falciparum drug resistance antimalarials genotype treatment outcome

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

RANDOMIZED

Intervention Model

PARALLEL

Primary Study Purpose

TREATMENT

Blinding Strategy

NONE

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

chloroquine

Intervention Type DRUG

sulfadoxine-pyrimethamine

Intervention Type DRUG

amodiaquine

Intervention Type DRUG

amodiaquine+artesunate

Intervention Type DRUG

amodiaquine+sulfadoxine-pyrimethamine

Intervention Type DRUG

sulfadoxine-pyrimethamine+artesunate

Intervention Type DRUG

artemether-lumefantrine

Intervention Type DRUG

mefloquine

Intervention Type DRUG

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

* Aged 6-59 months
* Absence of severe malnutrition (defined as a child whose weight-for-height is below 3 standard deviations of less than 70% of the median of World Health Organization (WHO) reference values, or who has symmetrical edema involving at least the feet)
* A slide-confirmed infection with P. falciparum only (i.e. no mixed infections)
* Initial parasite density between 2,000 and 200,000 asexual parasites per microliter.
* Absence of general danger signs among children \< 5 years (inability to drink or breastfeed; vomiting everything; recent history of convulsions; lethargy or unconsciousness; inability to sit or stand up) or other signs of severe and complicated falciparum malaria according to WHO definitions
* Measured axillary temperature ≥ 37.5 °C
* Ability to attend stipulated follow-up visits
* Informed consent provided by parent/guardian
* Absence of history of hypersensitivity reactions to any of the drugs being evaluated

Exclusion Criteria

* Aged \< 6 or \>59 months
* Severe malnutrition (defined as a child whose weight-for-height is below 3 standard deviations of less than 70% of the median of WHO reference values, or who has symmetrical edema involving at least the feet)
* No slide confirmed infection with P. falciparum or a mixed infection that includes a non P. falciparum species
* Initial parasite density \< 2,000 or \> 200,000 asexual parasites per microliter.
* Presence of general danger signs among children \< 5 years (inability to drink or breastfeed; vomiting everything; recent history of convulsions; lethargy or unconsciousness; inability to sit or stand up) or other signs of severe and complicated falciparum malaria according to WHO definitions
* Measured axillary temperature \<37.5 °C
* Inability to attend stipulated follow-up visits
* Unwilling to provide informed consent provided by parent/guardian
* History of hypersensitivity reactions to any of the drugs being evaluated
Minimum Eligible Age

6 Months

Maximum Eligible Age

59 Months

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

Malaria Research and Training Center, Bamako, Mali

OTHER

Sponsor Role collaborator

Centers for Disease Control and Prevention

FED

Sponsor Role lead

Principal Investigators

Learn about the lead researchers overseeing the trial and their institutional affiliations.

Robert D. Newman, MD, MPH

Role: PRINCIPAL_INVESTIGATOR

Centers for Disease Control and Prevention

Kassoum Kayentao, MD, MSPH

Role: PRINCIPAL_INVESTIGATOR

Malaria Research and Training Center, Bamako, Mali

John Barnwell, PhD, MPH

Role: PRINCIPAL_INVESTIGATOR

Centers for Disease Control and Prevention

Ogobara Doumbo, MD, PhD

Role: PRINCIPAL_INVESTIGATOR

Malaria Research and Training Center, Bamako, Mali

Locations

Explore where the study is taking place and check the recruitment status at each participating site.

Faladje Missionary Dispensary

Faladié, , Mali

Site Status

Koro Health Center

Koro, , Mali

Site Status

Pongono Community Health Center

Pongono, , Mali

Site Status

Countries

Review the countries where the study has at least one active or historical site.

Mali

References

Explore related publications, articles, or registry entries linked to this study.

WHO. Assessment and Monitoring of Antimalarial Drug Efficacy for the Treatment of Uncomplicated Falciparum Malaria. Geneva: World Health Organization, 2003

Reference Type BACKGROUND

Plowe CV. Monitoring antimalarial drug resistance: making the most of the tools at hand. J Exp Biol. 2003 Nov;206(Pt 21):3745-52. doi: 10.1242/jeb.00658.

Reference Type BACKGROUND
PMID: 14506209 (View on PubMed)

Wernsdorfer WH, Noedl H. Molecular markers for drug resistance in malaria: use in treatment, diagnosis and epidemiology. Curr Opin Infect Dis. 2003 Dec;16(6):553-8. doi: 10.1097/00001432-200312000-00007.

Reference Type BACKGROUND
PMID: 14624105 (View on PubMed)

Djimde A, Doumbo OK, Steketee RW, Plowe CV. Application of a molecular marker for surveillance of chloroquine-resistant falciparum malaria. Lancet. 2001 Sep 15;358(9285):890-1. doi: 10.1016/S0140-6736(01)06040-8. No abstract available.

Reference Type BACKGROUND
PMID: 11567708 (View on PubMed)

Djimde A, Doumbo OK, Cortese JF, Kayentao K, Doumbo S, Diourte Y, Coulibaly D, Dicko A, Su XZ, Nomura T, Fidock DA, Wellems TE, Plowe CV. A molecular marker for chloroquine-resistant falciparum malaria. N Engl J Med. 2001 Jan 25;344(4):257-63. doi: 10.1056/NEJM200101253440403.

Reference Type BACKGROUND
PMID: 11172152 (View on PubMed)

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

CDC-NCID-4314

Identifier Type: -

Identifier Source: org_study_id