Evidence map›Paper›PMID 40343740›Full record

ArticleThe Journal of antimicrobial chemotherapy2025

Plasmodium falciparum isolates: ex vivo drug response.

Edem Adika, Samirah Saiid, Enock K Amoako, Mona-Liza E Sakyi, Ahmed Osumanu, Collins Morang'a, Daniel Dosoo, Jersley D Chirawurah, Gordon A Awandare, Alfred Amambua-Ngwa and 2 more

Abstract read
In one paragraph

Article in The Journal of antimicrobial chemotherapy, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

12 authors.

Edem AdikaWest African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana.ORCID 0000-0003-4655-9515
Samirah SaiidWest African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana.
Enock K AmoakoWest African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana.
Mona-Liza E SakyiWest African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana.
Ahmed OsumanuWest African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana.
Collins Morang'aWest African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana.
Daniel DosooWest African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana.
Jersley D ChirawurahWest African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana.
Gordon A AwandareWest African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana.
Alfred Amambua-NgwaMedical Research Council Unit, The Gambia at LSHTM, Banjul, The Gambia.ORCID 0000-0003-4478-3601
Yaw AniwehWest African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana.
Lucas N Amenga-EtegoWest African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana.

Funding

Bill and Melinda Gates Foundation INV-050873European Union TMA2019SFP-2843World Bank African Centres of Excellence
6 · The paper itself

Abstract

objectivesWhile artemisinin-based combination therapies (ACTs) are effective in sub-Saharan Africa, clinical isolates that are refractory to artemisinin derivatives are emerging in East Africa and ACT partner drugs are becoming less effective in West Africa. We investigated the ex vivo responses of Plasmodium falciparum clinical isolates to frontline antimalarials and the contribution of validated molecular markers of antimalarial drug resistance.

methodsEx vivo susceptibility was measured for 66 clinical isolates collected from uncomplicated malaria patients. IC50 was measured for dihydroartemisinin, artesunate, lumefantrine, amodiaquine and chloroquine using a SYBR Green I growth inhibition assay. We also assessed known drug resistance-mediating polymorphisms in pfcrt, pfmdr1 and pfkelch13 using Oxford Nanopore amplicon sequencing.

resultsP. falciparum clinical isolates were susceptible to dihydroartemisinin and artesunate. Clinical isolates showed a wide distribution of susceptibility to lumefantrine and amodiaquine, with some parasites having IC50 values above reference cut-offs for resistance to lumefantrine (150 nM) and amodiaquine (60 nM), suggesting decreased drug susceptibility. Ninety-seven percent of the isolates carried WT pfcrt K76 and pfmdr1 N86 alleles, reported to mediate reduced response to lumefantrine and artemether/lumefantrine. pfmdr1 N86 and 184F haplotype was carried by 62.1% of parasites. None of the clinical isolates carried validated pfkelch13 mutations known to mediate artemisinin partial resistance.

conclusionsClinical isolates from coastal Ghana remain susceptible to artemisinin derivatives in commonly used ACTs in Ghana. However, we observed lower susceptibility to the ACT partner drugs lumefantrine and amodiaquine, suggesting the emergence of drug-tolerance phenotypes. Consistent surveillance of drug phenotype-genotype is needed to support ACT efficacy in Ghana.

Indexed as

AntimalarialsDrug ResistanceMalaria, FalciparumPlasmodium falciparumAmodiaquineArtemisininsATP-Binding Cassette, Sub-Family C ProteinsGenotypeHumansInhibitory Concentration 50Membrane Transport ProteinsParasitic Sensitivity TestsPolymorphism, GeneticProtozoan ProteinsAmodiaquineAntimalarialsArtemisininsATP-Binding Cassette, Sub-Family C ProteinsMdr1 protein, Plasmodium falciparumMembrane Transport ProteinsProtozoan Proteins

Identifiers

PMID40343740
PMCPMC12209805

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.