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Brown N, da Silva C, Webb C, Matias D, Dias B, Cancio B, Silva M, Viegas R, Salvador C, Chivale N, Luis S, Arnaldo P, Zulawinska J, Moore CC, Nogueira F, Guler JL. Antimalarial resistance risk in Mozambique detected by a novel quadruplex droplet digital PCR assay. Antimicrob Agents Chemother 2024:e0034624. [PMID: 38771031 DOI: 10.1128/aac.00346-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Accepted: 04/18/2024] [Indexed: 05/22/2024] Open
Abstract
While the Plasmodium falciparum malaria parasite continues to cause severe disease globally, Mozambique is disproportionally represented in malaria case totals. Acquisition of copy number variations (CNVs) in the parasite genome contributes to antimalarial drug resistance through overexpression of drug targets. Of interest, piperaquine resistance is associated with plasmepsin 2 and 3 CNVs (pfpmp2 and pfpmp3, respectively), while CNVs in the multidrug efflux pump, multidrug resistance-1 (pfmdr1), increase resistance to amodiaquine and lumefantrine. These antimalarials are partner drugs in artemisinin combination therapies (ACTs) and therefore, CNV detection with accurate and efficient tools is necessary to track ACT resistance risk. Here, we evaluated ~300 clinically derived samples collected from three sites in Mozambique for resistance-associated CNVs. We developed a novel, medium-throughput, quadruplex droplet digital PCR (ddPCR) assay to simultaneously quantify the copy number of pfpmp3, pfpmp2, and pfmdr1 loci in these clinical samples. By using DNA from laboratory parasite lines, we show that this nanodroplet-based method is capable of detecting picogram levels of parasite DNA, which facilitates its application for low yield and human host-contaminated clinical surveillance samples. Following ddPCR and the application of quality control standards, we detected CNVs in 13 of 229 high-quality samples (prevalence of 5.7%). Overall, our study revealed a low number of resistance CNVs present in the parasite population across all three collection sites, including various combinations of pfmdr1, pfpmp2, and pfpmp3 CNVs. The potential for future ACT resistance across Mozambique emphasizes the need for continued molecular surveillance across the region.
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Affiliation(s)
- Noah Brown
- Department of Biology, University of Virginia, Charlottesville, Virginia, USA
| | - Clemente da Silva
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Lisbon, Portugal
| | - Caroline Webb
- Department of Biology, University of Virginia, Charlottesville, Virginia, USA
| | - Daniela Matias
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Lisbon, Portugal
| | - Brigite Dias
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Lisbon, Portugal
| | - Beatriz Cancio
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Lisbon, Portugal
| | - Miguel Silva
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Lisbon, Portugal
| | - Ruben Viegas
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Lisbon, Portugal
| | | | - Nordino Chivale
- Instituto Nacional de Saúde, Maputo (INS), Maputo, Mozambique
| | - Sonia Luis
- Hospital Provincial de Matola, Matola, Mozambique
| | - Paulo Arnaldo
- Instituto Nacional de Saúde, Maputo (INS), Maputo, Mozambique
| | - Julia Zulawinska
- Department of Biology, University of Virginia, Charlottesville, Virginia, USA
| | - Christopher C Moore
- Division of Infectious Disease and International Health, University of Virginia, Charlottesville, Virginia, USA
| | - Fatima Nogueira
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Lisbon, Portugal
| | - Jennifer L Guler
- Department of Biology, University of Virginia, Charlottesville, Virginia, USA
- Division of Infectious Disease and International Health, University of Virginia, Charlottesville, Virginia, USA
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Adam M, Nahzat S, Kakar Q, Assada M, Witkowski B, Tag Eldin Elshafie A, Abuobaida D, Safi N, Khan MA, Nagi M, Mustafa SA, Kohestani K, Muhammad J, Khim N, Al-Hadi M, Elfaki TM, Habib MN, Khairy AKA, Hamid H, Uddin Z, Amer Y, Hassan AH, Elhag MS, Sediqi AW, Kakar I, Abdul-Ghani R, Amran JGH, Abdallrahim TA, Tamim MS, Aljasari A, Rasmussen C, Azkoul L, Warsame M. Antimalarial drug efficacy and resistance in malaria-endemic countries in HANMAT-PIAM_net countries of the Eastern Mediterranean Region 2016-2020: Clinical and genetic studies. Trop Med Int Health 2023; 28:817-829. [PMID: 37705047 DOI: 10.1111/tmi.13929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/15/2023]
Abstract
INTRODUCTION The World Health Organization recommends regular monitoring of the efficacy of nationally recommended antimalarial drugs. We present the results of studies on the efficacy of recommended antimalarials and molecular markers of artemisinin and partner resistance in Afghanistan, Pakistan, Somalia, Sudan and Yemen. METHODS Single-arm prospective studies were conducted to evaluate the efficacy of artesunate-sulfadoxine-pyrimethamine (ASSP) in Afghanistan and Pakistan, artemether-lumefantrine (AL) in all countries, or dihydroartemisinin-piperaquine (DP) in Sudan for the treatment of Plasmodium falciparum. The efficacy of chloroquine (CQ) and AL for the treatment of Plasmodium vivax was evaluated in Afghanistan and Somalia, respectively. Patients were treated and monitored for 28 (CQ, ASSP and AL) or 42 (DP) days. Polymerase chain reaction (PCR)-corrected cure rate and parasite positivity rate at Day 3 were estimated. Mutations in the P. falciparum kelch 13 (Pfk13) gene and amplifications of plasmepsin (Pfpm2) and multidrug resistance-1 (Pfmdr-1) genes were also studied. RESULTS A total of 1680 (249 for ASSP, 1079 for AL and 352 for DP) falciparum cases were successfully assessed. A PCR-adjusted ASSP cure rate of 100% was observed in Afghanistan and Pakistan. For AL, the cure rate was 100% in all but four sites in Sudan, where cure rates ranged from 92.1% to 98.8%. All but one patient were parasite-free at Day 3. For P. vivax, cure rates were 98.2% for CQ and 100% for AL. None of the samples from Afghanistan, Pakistan and Yemen had a Pfk13 mutation known to be associated with artemisinin resistance. In Sudan, the validated Pfk13 R622I mutation accounted for 53.8% (14/26) of the detected non-synonymous Pfk13 mutations, most of which were repeatedly detected in Gadaref. A prevalence of 2.7% and 9.3% of Pfmdr1 amplification was observed in Pakistan and Yemen, respectively. CONCLUSION High efficacy of ASSP, AL and DP in the treatment of uncomplicated falciparum infection and of CQ and AL in the treatment of P. vivax was observed in the respective countries. The repeated detection of a relatively high rate of Pfk13 R622I mutation in Sudan underscores the need for close monitoring of the efficacy of recommended ACTs, parasite clearance rates and Pfk13 mutations in Sudan and beyond. Registration numbers of the trials: ACTRN12622000944730 and ACTRN12622000873729 for Afghanistan, ACTRN12620000426987 and ACTRN12617001025325 for Pakistan, ACTRN12618001224213 for Somalia, ACTRN12617000276358, ACTRN12622000930785 and ACTRN12618001800213 for Sudan and ACTRN12617000283370 for Yemen.
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Affiliation(s)
| | - Sami Nahzat
- National Malaria and Leishmania Control Programme, Ministry of Public Health, Kabul, Afghanistan
| | | | - Methaq Assada
- National Malaria Control Programme, Ministry of Health, Sana'a, Yemen
| | - Benoit Witkowski
- Malaria Research Unit, Pasteur Institute of Cambodia, Phnom Penh, Cambodia
| | | | - Duha Abuobaida
- Communicable Diseases Control Directorate, Federal Ministry of Health, Khartoum, Sudan
| | | | - Munir Ahmed Khan
- Provincial Malaria and VBDs Control Programme, Quetta, Balochistan, Pakistan
| | - Mustafa Nagi
- National Malaria Control Programme, Ministry of Health, Sana'a, Yemen
| | - Sayed Ali Mustafa
- Communicable Diseases Control Directorate, Federal Ministry of Health, Khartoum, Sudan
| | - Khalilahmad Kohestani
- National Malaria and Leishmania Control Programme, Ministry of Public Health, Kabul, Afghanistan
| | - Jamil Muhammad
- Provincial Malaria and VBDs Control Programme, Khyber Pakhtunkhwa, Pakistan
| | - Nimol Khim
- Malaria Research Unit, Pasteur Institute of Cambodia, Phnom Penh, Cambodia
| | - Mohammed Al-Hadi
- National Malaria Control Programme, Ministry of Health, Sana'a, Yemen
| | - Tarig Mohamed Elfaki
- Communicable Diseases Control Directorate, Federal Ministry of Health, Khartoum, Sudan
| | - Muhammad Naeem Habib
- Malaria & Other Vector Borne Disease Program, Ministry of Public Health, Kabul, Afghanistan
| | | | - Hamida Hamid
- Malaria & Other Vector Borne Disease Program, Ministry of Public Health, Kabul, Afghanistan
| | - Zain Uddin
- District Headquarter Hospital, Zhob, Pakistan
| | - Yahya Amer
- Almarawiah Hospital Ministry of Health, Al Mahrah, Yemen
| | | | - Mousab Siddig Elhag
- Communicable Diseases Control Directorate, Federal Ministry of Health, Khartoum, Sudan
| | - Ahmad Walid Sediqi
- Global Fund Programme, United Nations Development Programme, Kabul, Afghanistan
| | - Inamullah Kakar
- Directorate of Malaria Control, Common Management Unit Global Fund grant for Malaria Control, Ministry of National Health Services Regulations and Coordination, Islamabad, Pakistan
| | - Rashad Abdul-Ghani
- Department of Medical Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen
| | | | | | - Mohammad Shoaib Tamim
- Malaria & Other Vector Borne Disease Program, Ministry of Public Health, Kabul, Afghanistan
| | | | | | | | - Marian Warsame
- School of Public Health and Community Medicine, University of Gothenburg, Gothenburg, Sweden
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Ndong Ngomo JM, Mawili-Mboumba DP, M’Bondoukwé NP, Ditombi BM, Koumba Lengongo JV, Batchy Ognagosso FB, Bouyou-Akotet MK. Drug Resistance Molecular Markers of Plasmodium falciparum and Severity of Malaria in Febrile Children in the Sentinel Site for Malaria Surveillance of Melen in Gabon: Additional Data from the Plasmodium Diversity Network African Network. Trop Med Infect Dis 2023; 8:184. [PMID: 37104310 PMCID: PMC10147079 DOI: 10.3390/tropicalmed8040184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 02/22/2023] [Accepted: 02/24/2023] [Indexed: 04/28/2023] Open
Abstract
The objective of this study was to analyze the relationship between the frequency of artemisinin-based combination (ACT) drug resistance molecular markers and clinical forms of P. falciparum malaria and parasitemia. A cross-sectional study was carried out between January and April 2014 at the Operational Clinical Research Unit of Melen in febrile children aged 12 to 240 months with a Plasmodium sp. infection. A total of 3 mL of peripheral blood collected from an EDTA tube was used for leukocyte depletion. DNA mutation detection was performed by next generation sequencing (NGS). A total of 1075 patients were screened for malaria. Among them, 384 had a Plasmodium infection. P. falciparum mono-infection was found in 98.9% of the patients. Pfcrt-326T mutation was found in all isolates, while 37.9% had Pfmdr2-484I mutant allele. The highest median parasite densities were found in patients infected by parasites carrying the CVIET haplotype of the Pfcrt gene. The different genetic profiles found here, and their variations according to clinical and biological signs of severe malaria, are additional arguments for the surveillance of P. falciparum strains.
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Affiliation(s)
- Jacques Mari Ndong Ngomo
- Faculty of Medicine, Department of Parasitology and Mycology, Université des Sciences de la Santé, Libreville BP 4009, Gabon
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Wakoli DM, Ondigo BN, Ochora DO, Amwoma JG, Okore W, Mwakio EW, Chemwor G, Juma J, Okoth R, Okudo C, Yeda R, Opot BH, Cheruiyot AC, Juma D, Roth A, Ogutu BR, Boudreaux D, Andagalu B, Akala HM. Impact of parasite genomic dynamics on the sensitivity of Plasmodium falciparum isolates to piperaquine and other antimalarial drugs. BMC Med 2022; 20:448. [PMID: 36397090 PMCID: PMC9673313 DOI: 10.1186/s12916-022-02652-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 11/07/2022] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Dihydroartemisinin-piperaquine (DHA-PPQ) is an alternative first-line antimalarial to artemether-lumefantrine in Kenya. However, recent reports on the emergence of PPQ resistance in Southeast Asia threaten its continued use in Kenya and Africa. In line with the policy on continued deployment of DHA-PPQ, it is imperative to monitor the susceptibility of Kenyan parasites to PPQ and other antimalarials. METHODS Parasite isolates collected between 2008 and 2021 from individuals with naturally acquired P. falciparum infections presenting with uncomplicated malaria were tested for in vitro susceptibility to piperaquine, dihydroartemisinin, lumefantrine, artemether, and chloroquine using the malaria SYBR Green I method. A subset of the 2019-2021 samples was further tested for ex vivo susceptibility to PPQ using piperaquine survival assay (PSA). Each isolate was also characterized for mutations associated with antimalarial resistance in Pfcrt, Pfmdr1, Pfpm2/3, Pfdhfr, and Pfdhps genes using real-time PCR and Agena MassARRAY platform. Associations between phenotype and genotype were also determined. RESULTS The PPQ median IC50 interquartile range (IQR) remained stable during the study period, 32.70 nM (IQR 20.2-45.6) in 2008 and 27.30 nM (IQR 6.9-52.8) in 2021 (P=0.1615). The median ex vivo piperaquine survival rate (IQR) was 0% (0-5.27) at 95% CI. Five isolates had a PSA survival rate of ≥10%, consistent with the range of PPQ-resistant parasites, though they lacked polymorphisms in Pfmdr1 and Plasmepsin genes. Lumefantrine and artemether median IC50s rose significantly to 62.40 nM (IQR 26.9-100.8) (P = 0.0201); 7.00 nM (IQR 2.4-13.4) (P = 0.0021) in 2021 from 26.30 nM (IQR 5.1-64.3); and 2.70 nM (IQR 1.3-10.4) in 2008, respectively. Conversely, chloroquine median IC50s decreased significantly to 10.30 nM (IQR 7.2-20.9) in 2021 from 15.30 nM (IQR 7.6-30.4) in 2008, coinciding with a decline in the prevalence of Pfcrt 76T allele over time (P = 0.0357). The proportions of piperaquine-resistant markers including Pfpm2/3 and Pfmdr1 did not vary significantly. A significant association was observed between PPQ IC50 and Pfcrt K76T allele (P=0.0026). CONCLUSIONS Circulating Kenyan parasites have remained sensitive to PPQ and other antimalarials, though the response to artemether (ART) and lumefantrine (LM) is declining. This study forms a baseline for continued surveillance of current antimalarials for timely detection of resistance.
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Affiliation(s)
- Dancan M Wakoli
- Department of Biochemistry and Molecular Biology, Egerton University, Egerton-Njoro, Kenya. .,Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/ Walter Reed Project, Kisumu, Kenya.
| | - Bartholomew N Ondigo
- Department of Biochemistry and Molecular Biology, Egerton University, Egerton-Njoro, Kenya.,Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, USA
| | - Douglas O Ochora
- Department of Plant Sciences, Microbiology & Biotechnology, College of Natural Sciences, Makerere University, Kampala, Uganda
| | - Joseph G Amwoma
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/ Walter Reed Project, Kisumu, Kenya.,Department of Biological Sciences, University of Embu, Embu, Kenya
| | - Winnie Okore
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/ Walter Reed Project, Kisumu, Kenya.,Department of Biomedical Sciences and Technology, School of Public Health and Community Development, Maseno University, Maseno, Kenya
| | - Edwin W Mwakio
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/ Walter Reed Project, Kisumu, Kenya
| | - Gladys Chemwor
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/ Walter Reed Project, Kisumu, Kenya
| | - Jackeline Juma
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/ Walter Reed Project, Kisumu, Kenya
| | - Raphael Okoth
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/ Walter Reed Project, Kisumu, Kenya
| | - Charles Okudo
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/ Walter Reed Project, Kisumu, Kenya
| | - Redemptah Yeda
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/ Walter Reed Project, Kisumu, Kenya
| | - Benjamin H Opot
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/ Walter Reed Project, Kisumu, Kenya
| | - Agnes C Cheruiyot
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/ Walter Reed Project, Kisumu, Kenya
| | - Dennis Juma
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/ Walter Reed Project, Kisumu, Kenya
| | - Amanda Roth
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/ Walter Reed Project, Kisumu, Kenya
| | - Benhards R Ogutu
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/ Walter Reed Project, Kisumu, Kenya
| | - Daniel Boudreaux
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/ Walter Reed Project, Kisumu, Kenya
| | - Ben Andagalu
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/ Walter Reed Project, Kisumu, Kenya
| | - Hoseah M Akala
- Department of Emerging and Infectious Diseases (DEID), United States Army Medical Research Directorate-Africa (USAMRD-A), Kenya Medical Research Institute (KEMRI)/ Walter Reed Project, Kisumu, Kenya.
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Mbye H, Mane K, Diop MF, Demba MA, Bojang F, Mohammed NI, Jeffries D, Quashie NB, D'Alessandro U, Amambua-Ngwa A. Plasmodium falciparum merozoite invasion ligands, linked antimalarial resistance loci and ex vivo responses to antimalarials in The Gambia. J Antimicrob Chemother 2022; 77:2946-2955. [PMID: 35904009 PMCID: PMC9616547 DOI: 10.1093/jac/dkac244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 06/23/2022] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Artemether/lumefantrine is the most commonly used artemisinin-based combination treatment (ACT) for malaria in sub-Saharan Africa. Drug resistance to ACT components is a major threat to malaria elimination efforts. Therefore, rigorous monitoring of drug efficacy is required for adequate management of malaria and to sustain the effectiveness of ACTs. OBJECTIVES This study identified and described genomic loci that correlate with differences in ex vivo responses of natural Plasmodium falciparum isolates from The Gambia to antimalarial drugs. METHODS Natural P. falciparum isolates from The Gambia were assayed for IC50 responses to four antimalarial drugs (artemether, dihydroartemisinin, amodiaquine and lumefantrine). Genome-wide SNPs from 56 of these P. falciparum isolates were applied to mixed-model regression and network analyses to determine linked loci correlating with drug responses. Genomic regions of shared haplotypes and positive selection within and between Gambian and Cambodian P. falciparum isolates were mapped by identity-by-descent (IBD) analysis of 209 genomes. RESULTS SNPs in 71 genes, mostly involved in stress and drug resistance mechanisms correlated with drug responses. Additionally, erythrocyte invasion and permeability loci, including merozoite surface proteins (Pfdblmsp, Pfsurfin), and high-molecular-weight rhoptry protein 2 (Pfrhops2) were correlated with responses to multiple drugs. Haplotypes of pfdblmsp2 and known drug resistance loci (pfaat1, pfcrt and pfdhfr) from The Gambia showed high IBD with those from Cambodia, indicating co-ancestry, with significant linkage disequilibrium between their alleles. CONCLUSIONS Multiple linked genic loci correlating with drug response phenotypes suggest a genomic backbone may be under selection by antimalarials. This calls for further analysis of molecular pathways to drug resistance in African P. falciparum.
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Affiliation(s)
- Haddijatou Mbye
- Medical Research Council at London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Karim Mane
- Medical Research Council at London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Mouhamadou Fadel Diop
- Medical Research Council at London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Martha Anita Demba
- Medical Research Council at London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Fatoumata Bojang
- Medical Research Council at London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | | | - David Jeffries
- Medical Research Council at London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | | | - Umberto D'Alessandro
- Medical Research Council at London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Alfred Amambua-Ngwa
- Medical Research Council at London School of Hygiene and Tropical Medicine, Fajara, The Gambia
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Efficacy of Artemether-Lumefantrine and Dihydroartemisinin-Piperaquine for the Treatment of Uncomplicated Plasmodium falciparum Malaria among Children in Western Kenya, 2016 to 2017. Antimicrob Agents Chemother 2022; 66:e0020722. [PMID: 36036611 PMCID: PMC9487560 DOI: 10.1128/aac.00207-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Antimalarial resistance threatens global malaria control efforts. The World Health Organization (WHO) recommends routine antimalarial efficacy monitoring through a standardized therapeutic efficacy study (TES) protocol. From June 2016 to March 2017, children with uncomplicated P. falciparum mono-infection in Siaya County, Kenya were enrolled into a standardized TES and randomized (1:1 ratio) to a 3-day course of artemether-lumefantrine (AL) or dihydroartemisinin-piperaquine (DP). Efficacy outcomes were measured at 28 and 42 days. A total of 340 children were enrolled. All but one child cleared parasites by day 3. PCR-corrected adequate clinical and parasitological response (ACPR) was 88.5% (95% CI: 80.9 to 93.3%) at day 28 for AL and 93.0% (95% CI: 86.9 to 96.4%) at day 42 for DP. There were 9.6 times (95% CI: 3.4 to 27.2) more reinfections in the AL arm compared to the DP arm at day 28, and 3.1 times (95% CI: 1.9 to 4.9) more reinfections at day 42. Both AL and DP were efficacious (per WHO 90% cutoff in the confidence interval) and well tolerated for the treatment of uncomplicated malaria in western Kenya, but AL efficacy appears to be waning. Further efficacy monitoring for AL, including pharmacokinetic studies, is recommended.
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Liu Y, Liang X, Li J, Chen J, Huang H, Zheng Y, He J, Ehapo CS, Eyi UM, Yang P, Lin L, Chen W, Sun G, Liu X, Zha G, Wang J, Wang C, Wei H, Lin M. Molecular Surveillance of Artemisinin-Based Combination Therapies Resistance in Plasmodium falciparum Parasites from Bioko Island, Equatorial Guinea. Microbiol Spectr 2022; 10:e0041322. [PMID: 35670601 PMCID: PMC9241599 DOI: 10.1128/spectrum.00413-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Artemisinin-based combination therapies (ACTs) resistance has emerged and could be diffusing in Africa. As an offshore island on the African continent, the island of Bioko in Equatorial Guinea is considered severely affected and resistant to drug-resistant Plasmodium falciparum malaria. However, the spatial and temporal distribution remain unclear. Molecular monitoring targeting the Pfcrt, Pfk13, Pfpm2, and Pfmdr1 genes was conducted to provide insight into the impact of current antimalarial drug resistance on the island. Furthermore, polymorphic characteristics, haplotype network, and the effect of natural selection of the Pfk13 gene were evaluated. A total of 152 Plasmodium falciparum samples (collected from 2017 to 2019) were analyzed for copy number variation of the Pfpm2 gene and Pfk13, Pfcrt, and Pfmdr1 mutations. Statistical analysis of Pfk13 sequences was performed following different evolutionary models using 96 Bioko sequences and 1322 global sequences. The results showed that the prevalence of Pfk13, Pfcrt, and Pfmdr1 mutations was 73.68%, 78.29%, and 75.66%, respectively. Large proportions of isolates with multiple copies of Pfpm2 were observed (67.86%). In Bioko parasites, the genetic diversity of Pfk13 was low, and purifying selection was suggested by Tajima's D test (-1.644, P > 0.05) and the dN/dS test (-0.0004438, P > 0.05). The extended haplotype homozygosity analysis revealed that Pfk13_K189T, although most frequent in Africa, has not yet conferred a selective advantage for parasitic survival. The results suggested that the implementation of continuous drug monitoring on Bioko Island is an essential measure. IMPORTANCE Malaria, one of the tropical parasitic diseases with a high transmission rate in Bioko Island, Equatorial Guinea, especially caused by P. falciparum is highly prevalent in this region and is commonly treated locally with ACTs. The declining antimalarial susceptibility of artemisinin-based drugs suggested that resistance to artemisinin and its derivatives is developing in P. falciparum. Copy number variants in Pfpm2 and genetic polymorphisms in Pfk13, Pfcrt, and Pfmdr1 can be used as risk assessment indicators to track the development and spread of drug resistance. This study reported for the first time the molecular surveillance of Pfpm2, Pfcrt, Pfk13, and Pfmdr1 genes in Bioko Island from 2017 to 2019 to assess the possible risk of local drug-resistant P. falciparum.
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Affiliation(s)
- YaQun Liu
- School of Food Engineering and Biotechnology, Hanshan Normal University, Chaozhou, Guangdong, People’s Republic of China
| | - XueYan Liang
- School of Food Engineering and Biotechnology, Hanshan Normal University, Chaozhou, Guangdong, People’s Republic of China
| | - Jian Li
- School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, Hubei, People’s Republic of China
| | - JiangTao Chen
- The Chinese Medical Aid Team to the Republic of Equatorial Guinea, Guangzhou, Guangdong, People's Republic of China
- Department of Medical Laboratory, Huizhou Central Hospital, Huizhou, Guangdong, People's Republic of China
| | - HuiYing Huang
- School of Food Engineering and Biotechnology, Hanshan Normal University, Chaozhou, Guangdong, People’s Republic of China
- School of Basic Medical Sciences, Hubei University of Medicine, Shiyan, Hubei, People’s Republic of China
| | - YuZhong Zheng
- School of Food Engineering and Biotechnology, Hanshan Normal University, Chaozhou, Guangdong, People’s Republic of China
| | - JinQuan He
- The Chinese Medical Aid Team to the Republic of Equatorial Guinea, Guangzhou, Guangdong, People's Republic of China
| | - Carlos Salas Ehapo
- Department of Medical Laboratory, Malabo Regional Hospital, Malabo, Equatorial Guinea
| | - Urbano Monsuy Eyi
- Department of Medical Laboratory, Malabo Regional Hospital, Malabo, Equatorial Guinea
| | - PeiKui Yang
- School of Food Engineering and Biotechnology, Hanshan Normal University, Chaozhou, Guangdong, People’s Republic of China
| | - LiYun Lin
- School of Food Engineering and Biotechnology, Hanshan Normal University, Chaozhou, Guangdong, People’s Republic of China
| | - WeiZhong Chen
- Department of Medical Laboratory, Chaozhou People’s Hospital Affiliated to Shantou University Medical College, Chaozhou, Guangdong, People's Republic of China
| | - GuangYu Sun
- Department of Medical Laboratory, Chaozhou People’s Hospital Affiliated to Shantou University Medical College, Chaozhou, Guangdong, People's Republic of China
| | - XiangZhi Liu
- Department of Medical Laboratory, Chaozhou People’s Hospital Affiliated to Shantou University Medical College, Chaozhou, Guangdong, People's Republic of China
| | - GuangCai Zha
- School of Food Engineering and Biotechnology, Hanshan Normal University, Chaozhou, Guangdong, People’s Republic of China
| | - JunLi Wang
- School of Laboratory Medicine, Youjiang Medical University for Nationalities, Baise, Guangxi, People’s Republic of China
| | - ChunFang Wang
- School of Laboratory Medicine, Youjiang Medical University for Nationalities, Baise, Guangxi, People’s Republic of China
| | - HuaGui Wei
- School of Laboratory Medicine, Youjiang Medical University for Nationalities, Baise, Guangxi, People’s Republic of China
| | - Min Lin
- School of Food Engineering and Biotechnology, Hanshan Normal University, Chaozhou, Guangdong, People’s Republic of China
- School of Laboratory Medicine, Youjiang Medical University for Nationalities, Baise, Guangxi, People’s Republic of China
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8
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Moss S, Mańko E, Krishna S, Campino S, Clark TG, Last A. How has mass drug administration with dihydroartemisinin-piperaquine impacted molecular markers of drug resistance? A systematic review. Malar J 2022; 21:186. [PMID: 35690758 PMCID: PMC9188255 DOI: 10.1186/s12936-022-04181-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 05/10/2022] [Indexed: 11/10/2022] Open
Abstract
The World Health Organization (WHO) recommends surveillance of molecular markers of resistance to anti-malarial drugs. This is particularly important in the case of mass drug administration (MDA), which is endorsed by the WHO in some settings to combat malaria. Dihydroartemisinin-piperaquine (DHA-PPQ) is an artemisinin-based combination therapy which has been used in MDA. This review analyses the impact of MDA with DHA-PPQ on the evolution of molecular markers of drug resistance. The review is split into two parts. Section I reviews the current evidence for different molecular markers of resistance to DHA-PPQ. This includes an overview of the prevalence of these molecular markers in Plasmodium falciparum Whole Genome Sequence data from the MalariaGEN Pf3k project. Section II is a systematic literature review of the impact that MDA with DHA-PPQ has had on the evolution of molecular markers of resistance. This systematic review followed PRISMA guidelines. This review found that despite being a recognised surveillance tool by the WHO, the surveillance of molecular markers of resistance following MDA with DHA-PPQ was not commonly performed. Of the total 96 papers screened for eligibility in this review, only 20 analysed molecular markers of drug resistance. The molecular markers published were also not standardized. Overall, this warrants greater reporting of molecular marker prevalence following MDA implementation. This should include putative pfcrt mutations which have been found to convey resistance to DHA-PPQ in vitro.
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Affiliation(s)
- Sophie Moss
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK.
| | - Emilia Mańko
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK
| | - Sanjeev Krishna
- Institute of Infection and Immunity, St George's University of London, London, UK
| | - Susana Campino
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK
| | - Taane G Clark
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, UK
| | - Anna Last
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK.
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9
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Assessing the Roles of Molecular Markers of Antimalarial Drug Resistance and the Host Pharmacogenetics in Drug-Resistant Malaria. J Trop Med 2022; 2022:3492696. [PMID: 35620049 PMCID: PMC9129956 DOI: 10.1155/2022/3492696] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 04/17/2022] [Accepted: 04/29/2022] [Indexed: 01/11/2023] Open
Abstract
Malaria caused by the Plasmodium parasites is a major public health concern in malaria-endemic regions with P. falciparum causing the most severe form of the disease. The use of antimalarial drugs for the management of the disease proves to be one of the best methods to manage the disease. Unfortunately, P. falciparum has developed resistance to almost all the current in-use antimalarial drugs. Parasite development of resistance is primarily caused by both parasite and host genetic factors. The parasite genetic factors involve undergoing mutation in the drug target sites or increasing the drug target gene copy number to prevent the intended action of the antimalarial drugs. The host pharmacogenetic factors which determine how a particular antimalarial drug is metabolized could result in variations of drug plasma concentration and consequently contribute to variable treatment outcomes and the emergence or propagation of resistant parasites. Since both host and parasite genomes play a role in antimalarial drug action, a key question often asked is, “which of the two strongly drives or controls antimalarial drug resistance?” A major finding in our recent study published in the Malaria Journal indicates that the parasite's genetic factors rather than the host are likely to energize resistance to an antimalarial drug. However, others have reported contrary findings suggesting that the host genetic factors are the force behind resistance to antimalarial drugs. To bring clarity to these observations, there is the need for deciphering the major driving force behind antimalarial drug resistance through optimized strategies aimed at alleviating the phenomenon. In this direction, literature was systematically reviewed to establish the role and importance of each of the two factors aforementioned in the etiology of drug-resistant malaria. Using Internet search engines such as Pubmed and Google, we looked for terms likely to give the desired information which we herein present. We then went ahead to leverage the obtained information to discuss the globally avid aim of combating antimalarial drug resistance.
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10
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Koko VS, Warsame M, Vonhm B, Jeuronlon MK, Menard D, Ma L, Taweh F, Tehmeh L, Nyansaiye P, Pratt OJ, Parwon S, Kamara P, Asinya M, Kollie A, Ringwald P. Artesunate-amodiaquine and artemether-lumefantrine for the treatment of uncomplicated falciparum malaria in Liberia: in vivo efficacy and frequency of molecular markers. Malar J 2022; 21:134. [PMID: 35477399 PMCID: PMC9044686 DOI: 10.1186/s12936-022-04140-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 03/27/2022] [Indexed: 11/21/2022] Open
Abstract
Background Artesunate–amodiaquine (ASAQ) and Artemether–lumefantrine (AL) are the recommended treatment for uncomplicated Plasmodium falciparum malaria in Liberia. Intermittent preventive treatment with sulfadoxine/pyrimethamine is also recommended for pregnant women. The therapeutic efficacy of Artesunate–amodiaquine and Artemether–lumefantrine, and the frequency of molecular markers associated with anti-malarial drug resistance were investigated. Methods The therapeutic efficacy of ASAQ and AL was evaluated using the standard World Health Organization protocol (WHO. Methods for Surveillance of Antimalarial Drug Efficacy. Geneva: World Health Organization; 2009. https://www.who.int/malaria/publications/atoz/9789241597531/en/). Eligible children were recruited and monitored clinically and parasitologically for 28 days. Polymorphisms in the Pfkelch 13, chloroquine resistance transporter (Pfcrt), multidrug resistance 1 (Pfmdr-1), dihydrofolate reductase (Pfdhfr), and dihydropteroate synthase (Pfdhps) genes and copy number variations in the plasmepsin-2 (Pfpm2) gene were assessed in pretreatment samples. Results Of the 359 children enrolled, 180 were treated with ASAQ (89 in Saclepea and 91 in Bensonville) and 179 with AL (90 in Sinje and 89 in Kakata). Of the recruited children, 332 (92.5%) reached study endpoints. PCR-corrected per-protocol analysis showed ACPR of 90.2% (95% CI: 78.6–96.7%) in Bensonville and 92.7% (95% CI: 83.4.8–96.5%) in Saclepea for ASAQ, while ACPR of 100% was observed in Kakata and Sinje for AL. In both treatment groups, only two patients had parasites on day 3. No artemisinin resistance associated Pfkelch13 mutations or multiple copies of Pfpm2 were found. Most samples tested had the Pfcrt 76 T mutation (80/91, 87.9%), while the Pfmdr-1 86Y (40/91, 44%) and 184F (47/91, 51.6%) mutations were less frequent. The Pfdhfr triple mutant (51I/59R/108 N) was the predominant allele (49.2%). For the Pfdhps gene, it was the 540E mutant (16.0%), and the 436A mutant (14.3%). The quintuple allele (51I/59R/108 N-437G/540E) was detected in only one isolate (1/357). Conclusion This study reports a decline in the efficacy of ASAQ treatment, while AL remained highly effective, supporting the recent decision by NMCP to replace ASAQ with AL as first-line treatment for uncomplicated falciparum malaria. No association between the presence of the mutations in Pfcrt and Pfmdr-1 and the risk of parasite recrudescence in patients treated with ASAQ was observed. Parasites with signatures known to be associated with artemisinin and piperaquine resistance were not detected. The very low frequency of the quintuple Pfdhfr/Pfdhps mutant haplotype supports the continued use of SP for IPTp. Monitoring of efficacy and resistance markers of routinely used anti-malarials is necessary to inform malaria treatment policy. Trial registration ACTRN12617001064392. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-022-04140-7.
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Affiliation(s)
- Victor S Koko
- National Malaria Control Programme, Ministry of Health, Monrovia, Liberia.
| | - Marian Warsame
- School of Public Health and Community Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Benjamin Vonhm
- National Public Health Institute of Liberia-NPHIL, Monrovia, Liberia
| | | | - Didier Menard
- Malaria Genetics and Resistance Unit, INSERM U1201, Institut Pasteur, Paris, France.,Laboratoire de Parasitologie et Mycologie Médicale, Hôpitaux Universitaires de Strasbourg, Strasbourg, France.,Institut de Parasitologie et Pathologie Tropicale, UR7292 Dynamique des Interactions Hôte Pathogène, Fédération de Médecine Translationnelle, Université de Strasbourg, Strasbourg, France
| | - Laurence Ma
- Biomics Platform, C2RT, Institut Pasteur, Paris, France
| | - Fahn Taweh
- National Public Health Institute of Liberia-NPHIL, Monrovia, Liberia
| | - Lekilay Tehmeh
- Quality Control Unit, Ministry of Health, Monrovia, Liberia
| | - Paye Nyansaiye
- National Malaria Control Programme, Ministry of Health, Monrovia, Liberia
| | - Oliver J Pratt
- National Malaria Control Programme, Ministry of Health, Monrovia, Liberia
| | - Sei Parwon
- Saclepea Comprehensive Health Center, Saclepea, Ministry of Health, Saclepea, Liberia
| | - Patrick Kamara
- Sinje Health Centre, Garwula, Ministery of Health, Garwula, Liberia
| | - Magnus Asinya
- Charles Henry Rennie Hospital, Kakata, Ministry of Health, Kakata, Liberia
| | - Aaron Kollie
- Bensonville Hospital, Bensonville, Ministry of Health, Bensonville, Liberia
| | - Pascal Ringwald
- Global Malaria Programme, World Health Organization, Geneva, Switzerland
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11
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Marwa K, Kapesa A, Baraka V, Konje E, Kidenya B, Mukonzo J, Kamugisha E, Swedberg G. Therapeutic efficacy of artemether-lumefantrine, artesunate-amodiaquine and dihydroartemisinin-piperaquine in the treatment of uncomplicated Plasmodium falciparum malaria in Sub-Saharan Africa: A systematic review and meta-analysis. PLoS One 2022; 17:e0264339. [PMID: 35271592 PMCID: PMC8912261 DOI: 10.1371/journal.pone.0264339] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 02/08/2022] [Indexed: 12/04/2022] Open
Abstract
Background Sub-Saharan Africa has the highest burden of malaria in the world. Artemisinin-based combination therapies (ACTs) have been the cornerstone in the efforts to reduce the global burden of malaria. In the effort to facilitate early detection of resistance for artemisinin derivatives and partner drugs, WHO recommends monitoring of ACT’s efficacy in the malaria endemic countries. The present systematic meta-analysis study summarises the evidence of therapeutic efficacy of the commonly used artemisinin-based combinations for the treatment of uncomplicated P. falciparum malaria in Sub-Saharan Africa after more than a decade since the introduction of the drugs. Methods Fifty two studies carried out from 2010 to 2020 on the efficacy of artemether-lumefantrine or dihydro-artemisinin piperaquine or artesunate amodiaquine in patients with uncomplicated P. falciparum malaria in Sub-Saharan Africa were searched for using the Google Scholar, Cochrane Central Register of controlled trials (CENTRAL), PubMed, Medline, LILACS, and EMBASE online data bases. Data was extracted by two independent reviewers. Random analysis effect was performed in STATA 13. Heterogeneity was established using I2 statistics. Results Based on per protocol analysis, unadjusted cure rates in malaria infected patients treated with artemether-lumefantrine (ALU), artesunate-amodiaquine (ASAQ) and dihydroartemisinin-piperaquine (DHP) were 89%, 94% and 91% respectively. However, the cure rates after PCR correction were 98% for ALU, 99% for ASAQ and 99% for DHP. Conclusion The present meta-analysis reports the overall high malaria treatment success for artemether-lumefantrine, artesunate-amodiaquine and dihydroartemisinin-piperaquine above the WHO threshold value in Sub-Saharan Africa.
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Affiliation(s)
- Karol Marwa
- Department of Pharmacology, Catholic University of Health and Allied Sciences, Mwanza, Tanzania
- * E-mail: ,
| | - Anthony Kapesa
- Department of Community Medicine, Catholic University of Health and Allied Sciences, Mwanza, Tanzania
| | - Vito Baraka
- National Institute for Medical Research, Tanga Centre, Tanga, Tanzania
| | - Evelyne Konje
- Department of Epidemiology, Catholic University of Health and Allied Sciences, Mwanza, Tanzania
| | - Benson Kidenya
- Department of Biochemistry, Catholic University of Health and Allied Sciences, Mwanza, Tanzania
| | - Jackson Mukonzo
- Department of Pharmacology and Therapeutics, Makerere University, Kampala, Uganda
| | - Erasmus Kamugisha
- Department of Biochemistry, Catholic University of Health and Allied Sciences, Mwanza, Tanzania
| | - Gote Swedberg
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
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12
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Zupko RJ, Nguyen TD, Somé AF, Tran TNA, Gerardin J, Dudas P, Giang DDH, Tran KT, Wesolowski A, Ouédraogo JB, Boni MF. Long-term effects of increased adoption of artemisinin combination therapies in Burkina Faso. PLOS GLOBAL PUBLIC HEALTH 2022; 2:e0000111. [PMID: 36962300 PMCID: PMC10021447 DOI: 10.1371/journal.pgph.0000111] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 01/09/2022] [Indexed: 11/18/2022]
Abstract
Artemisinin combination therapies (ACTs) are the WHO-recommended first-line therapies for uncomplicated Plasmodium falciparum malaria. The emergence and spread of artemisinin-resistant genotypes is a major global public health concern due to the increased rate of treatment failures that result. This is particularly germane for WHO designated 'high burden to high impact' (HBHI) countries, such as Burkina Faso, where there is increased emphasis on improving guidance, strategy, and coordination of local malaria response in an effort to reduce the prevalence of P. falciparum malaria. To explore how the increased adoption of ACTs may affect the HBHI malaria setting of Burkina Faso, we added spatial structure to a validated individual-based stochastic model of P. falciparum transmission and evaluated the long-term effects of increased ACT use. We explored how de novo emergence of artemisinin-resistant genotypes, such as pfkelch13 580Y, may occur under scenarios in which private-market drugs are eliminated or multiple first-line therapies (MFT) are deployed. We found that elimination of private market drugs would result in lower treatment failures rates (between 11.98% and 12.90%) when compared to the status quo (13.11%). However, scenarios incorporating MFT with equal deployment of artemether-lumefantrine (AL) and dihydroartemisinin-piperaquine (DHA-PPQ) may accelerate near-term drug resistance (580Y frequency ranging between 0.62 to 0.84 in model year 2038) and treatment failure rates (26.69% to 34.00% in 2038), due to early failure and substantially reduced treatment efficacy resulting from piperaquine-resistant genotypes. A rebalanced MFT approach (90% AL, 10% DHA-PPQ) results in approximately equal long-term outcomes to using AL alone but may be difficult to implement in practice.
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Affiliation(s)
- Robert J Zupko
- Center for Infectious Disease Dynamics, Department of Biology, Pennsylvania State University, University Park, PA, United States of America
| | - Tran Dang Nguyen
- Center for Infectious Disease Dynamics, Department of Biology, Pennsylvania State University, University Park, PA, United States of America
| | - Anyirékun Fabrice Somé
- Institut de Recherche en Sciences de la Santé, Direction Régionale de l'Ouest, Bobo Dioulasso, Burkina Faso
| | - Thu Nguyen-Anh Tran
- Center for Infectious Disease Dynamics, Department of Biology, Pennsylvania State University, University Park, PA, United States of America
| | - Jaline Gerardin
- Department of Preventive Medicine and Institute for Global Health, Northwestern University, Chicago, IL, United States of America
| | - Patrick Dudas
- Institute for Computational and Data Sciences, Pennsylvania State University, University Park, PA, United States of America
| | - Dang Duy Hoang Giang
- Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam
| | - Kien Trung Tran
- Center for Infectious Disease Dynamics, Department of Biology, Pennsylvania State University, University Park, PA, United States of America
| | - Amy Wesolowski
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States of America
| | | | - Maciej F Boni
- Center for Infectious Disease Dynamics, Department of Biology, Pennsylvania State University, University Park, PA, United States of America
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
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13
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Mairet-Khedim M, Nsango S, Ngou C, Menard S, Roesch C, Khim N, Srun S, Iriart X, Lanot T, Otam L, Abega F, Ayong L, Morlais I, Gandia P, Witkowski B, Berry A. Efficacy of dihydroartemisinin/piperaquine in patients with non-complicated Plasmodium falciparum malaria in Yaoundé, Cameroon. J Antimicrob Chemother 2021; 76:3037-3044. [PMID: 34453535 DOI: 10.1093/jac/dkab281] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 07/12/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Dihydroartemisinin/piperaquine is increasingly used for the treatment of uncomplicated Plasmodium falciparum malaria in Africa. The efficacy of this combination in Cameroon is poorly documented, while resistance to dihydroartemisinin/piperaquine readily spreads in Southeast Asia. OBJECTIVES This study evaluated the clinical efficacy of dihydroartemisinin/piperaquine in Cameroon, as well as the molecular profile and phenotypic susceptibility of collected isolates to dihydroartemisinin and piperaquine. PATIENTS AND METHODS Dihydroartemisinin/piperaquine efficacy in 42 days was followed-up for 138 patients presenting non-complicated falciparum malaria. Piperaquine concentration was determined at day 7 for 124 patients. kelch13 gene polymorphisms (n = 150) and plasmepsin2 gene amplification (n = 148) were determined as molecular markers of resistance to dihydroartemisinin and piperaquine, respectively. Parasite susceptibility to dihydroartemisinin and piperaquine was determined using validated in vitro survival assays. RESULTS The efficacy of dihydroartemisinin/piperaquine treatment was 100% after PCR correction. The reinfections were not associated with a variation of piperaquine concentration at day 7. Ninety-six percent (144/150) of the samples presented a WT allele of the kelch13 gene. Two percent (3/150) presented the non-synonymous mutation A578S, which is not associated with resistance to dihydroartemisinin. No duplication of the plasmepsin2 gene was observed (0/148). All the samples tested in vitro by survival assays (n = 87) were susceptible to dihydroartemisinin and piperaquine. CONCLUSIONS Dihydroartemisinin/piperaquine has demonstrated excellent therapeutic efficacy with no evidence of emerging artemisinin or piperaquine resistance in Yaoundé, Cameroon. This observation suggests that dihydroartemisinin/piperaquine could be a sustainable therapeutic solution for P. falciparum malaria if implemented in areas previously free of artemisinin- and piperaquine-resistant parasites, unlike Southeast Asia.
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Affiliation(s)
- Mélissa Mairet-Khedim
- Malaria Translational Research Unit, Pasteur International Unit, Pasteur International Network, Phnom Penh, Cambodia and Paris, France.,Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), Université Toulouse, CNRS UMR5051, INSERM UMR1291, UPS, Toulouse, France.,Structural Microbiology Unit, Institut Pasteur, CNRS UMR 3528, 25 rue du Docteur Roux, 75724 Paris 15, France
| | - Sandrine Nsango
- Department of Biological Sciences, Faculté de Médecine et des Sciences Pharmaceutiques, Université de Douala, Douala, Cameroon.,Malaria Research Unit, Centre Pasteur du Cameroon, Yaoundé, Cameroon
| | - Christelle Ngou
- Malaria Research Unit, Centre Pasteur du Cameroon, Yaoundé, Cameroon.,MIVEGEC, IRD, CNRS, Univ. Montpellier, Montpellier, France
| | - Sandie Menard
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), Université Toulouse, CNRS UMR5051, INSERM UMR1291, UPS, Toulouse, France
| | - Camille Roesch
- Malaria Translational Research Unit, Pasteur International Unit, Pasteur International Network, Phnom Penh, Cambodia and Paris, France.,Malaria Molecular Epidemiology Unit, Institut Pasteur du Cambodge, Phnom Penh, Cambodia
| | - Nimol Khim
- Malaria Translational Research Unit, Pasteur International Unit, Pasteur International Network, Phnom Penh, Cambodia and Paris, France.,Malaria Molecular Epidemiology Unit, Institut Pasteur du Cambodge, Phnom Penh, Cambodia
| | - Sreynet Srun
- Malaria Translational Research Unit, Pasteur International Unit, Pasteur International Network, Phnom Penh, Cambodia and Paris, France.,Malaria Molecular Epidemiology Unit, Institut Pasteur du Cambodge, Phnom Penh, Cambodia
| | - Xavier Iriart
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), Université Toulouse, CNRS UMR5051, INSERM UMR1291, UPS, Toulouse, France.,Service de Parasitologie-Mycologie, Centre Hospitalier Universitaire de Toulouse, Hôpital Purpan, Toulouse F-31300, France
| | - Thomas Lanot
- Laboratoire de Pharmacocinétique et Toxicologie, Centre Hospitalier Universitaire de Toulouse, Hôpital Purpan, Toulouse F-31300, France
| | - Laure Otam
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), Université Toulouse, CNRS UMR5051, INSERM UMR1291, UPS, Toulouse, France.,Département des Sciences Biomédicales, Faculté des Sciences, Université de Ngaoundéré, Ngaoundéré, Cameroon
| | | | - Lawrence Ayong
- Malaria Research Unit, Centre Pasteur du Cameroon, Yaoundé, Cameroon
| | | | - Peggy Gandia
- Laboratoire de Pharmacocinétique et Toxicologie, Centre Hospitalier Universitaire de Toulouse, Hôpital Purpan, Toulouse F-31300, France.,INTHERES, Université de Toulouse, INRA, ENVT, BP 87614, 31076 Toulouse Cedex 3, France
| | - Benoit Witkowski
- Malaria Translational Research Unit, Pasteur International Unit, Pasteur International Network, Phnom Penh, Cambodia and Paris, France.,Malaria Molecular Epidemiology Unit, Institut Pasteur du Cambodge, Phnom Penh, Cambodia
| | - Antoine Berry
- Institut Toulousain des Maladies Infectieuses et Inflammatoires (Infinity), Université Toulouse, CNRS UMR5051, INSERM UMR1291, UPS, Toulouse, France.,Service de Parasitologie-Mycologie, Centre Hospitalier Universitaire de Toulouse, Hôpital Purpan, Toulouse F-31300, France
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14
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Dini S, Zaloumis SG, Price DJ, Gobeau N, Kümmel A, Cherkaoui M, Moehrle JJ, McCarthy JS, Simpson JA. Seeking an optimal dosing regimen for OZ439/DSM265 combination therapy for treating uncomplicated falciparum malaria. J Antimicrob Chemother 2021; 76:2325-2334. [PMID: 34179977 DOI: 10.1093/jac/dkab181] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 05/02/2021] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The efficacy of artemisinin-based combination therapies (ACTs), the first-line treatments for uncomplicated falciparum malaria, has been declining in malaria-endemic countries due to the emergence of malaria parasites resistant to these compounds. Novel alternative therapies are needed urgently to prevent the likely surge in morbidity and mortality due to failing ACTs. OBJECTIVES This study investigates the efficacy of the combination of two novel drugs, OZ439 and DSM265, using a biologically informed within-host mathematical model. METHODS A within-host model was developed, which accounts for the differential killing of these compounds against different stages of the parasite's life cycle and accommodates the pharmacodynamic interaction between the drugs. Data of healthy volunteers infected with falciparum malaria collected from four trials (three that administered OZ439 and DSM265 alone, and the fourth a combination of OZ439 and DSM265) were analysed. Model parameters were estimated in a hierarchical Bayesian framework. RESULTS The posterior predictive simulations of our model predicted that 800 mg of OZ439 combined with 450 mg of DSM265, which are within the safe and tolerable dose range, can provide above 90% cure rates 42 days after drug administration. CONCLUSIONS Our results show that the combination of OZ439 and DSM265 can be a promising alternative to replace ACTs. Our model can be used to inform future Phase 2 and 3 clinical trials of OZ439/DSM265, fast-tracking the deployment of this combination therapy in the regions where ACTs are failing. The dosing regimens that are shown to be efficacious and within safe and tolerable limits are suggested for future investigations.
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Affiliation(s)
- Saber Dini
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Australia
| | - Sophie G Zaloumis
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Australia
| | - David J Price
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Australia.,Doherty Institute for Infection and Immunity, University of Melbourne and Royal Melbourne Hospital, Melbourne, Australia
| | | | | | | | | | - James S McCarthy
- Doherty Institute for Infection and Immunity, University of Melbourne and Royal Melbourne Hospital, Melbourne, Australia.,QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Julie A Simpson
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Australia
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Ashley EA, Poespoprodjo JR. Treatment and prevention of malaria in children. THE LANCET CHILD & ADOLESCENT HEALTH 2020; 4:775-789. [PMID: 32946831 DOI: 10.1016/s2352-4642(20)30127-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 03/11/2020] [Accepted: 03/25/2020] [Indexed: 10/23/2022]
Abstract
Malaria disproportionately affects children younger than 5 years. Falciparum malaria is responsible for more than 200 000 child deaths per year in Africa and vivax malaria is well documented as a cause of severe anaemia and excess mortality in children in Asia and Oceania. For the treatment of malaria in children, paediatric dosing recommendations for several agents, including parenteral artesunate and dihydroartemisinin-piperaquine, have belatedly been shown to be suboptimal. Worsening antimalarial resistance in Plasmodium falciparum in the Greater Mekong Subregion threatens to undermine global efforts to control malaria. Triple antimalarial combination therapies are being evaluated to try to impede this threat. The RTS,S/AS01 vaccine gives partial protection against falciparum malaria and is being evaluated in large, pilot studies in Ghana, Malawi, and Kenya as a complementary tool to other preventive measures. Seasonal malaria chemoprevention in west Africa has resulted in declines in malaria incidence and deaths and there is interest in scaling up efforts by expanding the age range of eligible recipients. Preventing relapse in Plasmodium vivax infection with primaquine is challenging because treating children who have G6PD deficiency with primaquine can cause acute haemolytic anaemia. The safety of escalating dose regimens for primaquine is being studied to mitigate this risk.
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Affiliation(s)
- Elizabeth A Ashley
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Vientiane, Laos; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
| | - Jeanne Rini Poespoprodjo
- Timika Research Facility, Papuan Health and Community Development Foundation, Timika, Indonesia; Department of Child Health, Faculty of Medicine, Public Health and Nursing, Gadjah Mada University, Yogyakarta, Indonesia
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Ansbro MR, Jacob CG, Amato R, Kekre M, Amaratunga C, Sreng S, Suon S, Miotto O, Fairhurst RM, Wellems TE, Kwiatkowski DP. Development of copy number assays for detection and surveillance of piperaquine resistance associated plasmepsin 2/3 copy number variation in Plasmodium falciparum. Malar J 2020; 19:181. [PMID: 32404110 PMCID: PMC7218657 DOI: 10.1186/s12936-020-03249-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 04/29/2020] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Long regarded as an epicenter of drug-resistant malaria, Southeast Asia continues to provide new challenges to the control of Plasmodium falciparum malaria. Recently, resistance to the artemisinin combination therapy partner drug piperaquine has been observed in multiple locations across Southeast Asia. Genetic studies have identified single nucleotide polymorphisms as well as copy number variations in the plasmepsin 2 and plasmepsin 3 genes, which encode haemoglobin-degrading proteases that associate with clinical and in vitro piperaquine resistance. RESULTS To accurately and quickly determine the presence of copy number variations in the plasmepsin 2/3 genes in field isolates, this study developed a quantitative PCR assay using TaqMan probes. Copy number estimates were validated using a separate SYBR green-based quantitative PCR assay as well as a novel PCR-based breakpoint assay to detect the hybrid gene product. Field samples from 2012 to 2015 across three sites in Cambodia were tested using DNA extracted from dried blood spots and whole blood to monitor the extent of plasmepsin 2/3 gene amplifications, as well as amplifications in the multidrug resistance transporter 1 gene (pfmdr1), a marker of mefloquine resistance. This study found high concordance across all methods of copy number detection. For samples derived from dried blood spots, a success rate greater than 80% was found in each assay, with more recent samples performing better. Evidence of extensive plasmepsin 2/3 copy number amplifications was observed in Pursat (94%, 2015) (Western Cambodia) and Preah Vihear (87%, 2014) (Northern Cambodia), and lower levels in Ratanakiri (16%, 2014) (Eastern Cambodia). A shift was observed from two copies of plasmepsin 2 in Pursat in 2013 to three copies in 2014-2015 (25% to 64%). Pfmdr1 amplifications were absent in all samples from Preah Vihear and Ratanakiri in 2014 and absent in Pursat in 2015. CONCLUSIONS The multiplex TaqMan assay is a robust tool for monitoring both plasmepsin 2/3 and pfmdr1 copy number variations in field isolates, and the SYBR-green and breakpoint assays are useful for monitoring plasmepsin 2/3 amplifications. This study shows increasing levels of plasmepsin 2 copy numbers across Cambodia from 2012 to 2015 and a complete reversion of multicopy pfmdr1 parasites to single copy parasites in all study locations.
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Affiliation(s)
- Megan R Ansbro
- Wellcome Sanger Institute, Hinxton, UK.
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA.
| | | | | | | | - Chanaki Amaratunga
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Sokunthea Sreng
- National Center for Parasitology, Entomology, and Malaria Control, Phnom Penh, Cambodia
| | - Seila Suon
- National Center for Parasitology, Entomology, and Malaria Control, Phnom Penh, Cambodia
| | - Olivo Miotto
- Wellcome Sanger Institute, Hinxton, UK
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Centre for Genomics and Global Health, Wellcome Centre for Human Genetics, Oxford, UK
| | - Rick M Fairhurst
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Thomas E Wellems
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Dominic P Kwiatkowski
- Wellcome Sanger Institute, Hinxton, UK
- Centre for Genomics and Global Health, Wellcome Centre for Human Genetics, Oxford, UK
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The impact of antimalarial resistance on the genetic structure of Plasmodium falciparum in the DRC. Nat Commun 2020; 11:2107. [PMID: 32355199 PMCID: PMC7192906 DOI: 10.1038/s41467-020-15779-8] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 03/28/2020] [Indexed: 11/09/2022] Open
Abstract
The Democratic Republic of the Congo (DRC) harbors 11% of global malaria cases, yet little is known about the spatial and genetic structure of the parasite population in that country. We sequence 2537 Plasmodium falciparum infections, including a nationally representative population sample from DRC and samples from surrounding countries, using molecular inversion probes - a high-throughput genotyping tool. We identify an east-west divide in haplotypes known to confer resistance to chloroquine and sulfadoxine-pyrimethamine. Furthermore, we identify highly related parasites over large geographic distances, indicative of gene flow and migration. Our results are consistent with a background of isolation by distance combined with the effects of selection for antimalarial drug resistance. This study provides a high-resolution view of parasite genetic structure across a large country in Africa and provides a baseline to study how implementation programs may impact parasite populations. The genome of the malaria parasite Plasmodium falciparum contains a record of past evolutionary forces. Here, using 2537 parasite sequences from the Democratic Republic of the Congo, the authors demonstrate how drug pressure and human movement have shaped the present-day parasite population.
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Conrad MD, Rosenthal PJ. Antimalarial drug resistance in Africa: the calm before the storm? THE LANCET. INFECTIOUS DISEASES 2019; 19:e338-e351. [DOI: 10.1016/s1473-3099(19)30261-0] [Citation(s) in RCA: 130] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 04/09/2019] [Accepted: 05/09/2019] [Indexed: 11/26/2022]
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Ishengoma DS, Saidi Q, Sibley CH, Roper C, Alifrangis M. Deployment and utilization of next-generation sequencing of Plasmodium falciparum to guide anti-malarial drug policy decisions in sub-Saharan Africa: opportunities and challenges. Malar J 2019; 18:267. [PMID: 31477109 PMCID: PMC6719357 DOI: 10.1186/s12936-019-2853-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 06/22/2019] [Indexed: 01/13/2023] Open
Abstract
Parasite resistance against anti-malarial drugs is a major threat to the ongoing malaria control and elimination strategies. This is especially true since resistance to the currently recommended artemisinins and partner drugs has been confirmed in South East Asia (SEA) and new anti-malarial compounds are not expected to be available in the near future. Spread from SEA or independent emergence of artemisinin resistance in sub-Saharan Africa (SSA) could reverse the achievements in malaria control that have been attained in the past two decades and derail the ongoing elimination strategies. The current surveillance of clinical efficacy and resistance to anti-malarial drugs is based on efficacy trials to assess the clinical performance of anti-malarials, in vivo/ex vivo assessment of parasite susceptibility to anti-malarials and prevalence of known molecular markers of drug resistance. Whereas clinical efficacy trials are restricted by cost and the complex logistics of patient follow-up, molecular detection of genetic mutations associated with resistance or reduced susceptibility to anti-malarials is by contrast a simple and powerful tool for early detection and monitoring of the prevalence of resistant parasites at population level. This provides needed information before clinical failure emerges, allowing policy makers to anticipate problems and respond. The various methods previously used in detection of molecular markers of drug resistance share some limitations: low-throughput, and high costs per sample and demanding infrastructure. However, recent technological advances including next-generation sequencing (NGS) methodologies promise greatly increased throughput and reduced costs, essentially providing unprecedented potential to address different research and operational questions of relevance for drug policy. This review assesses the potential role of NGS to provide comprehensive information that could guide drug policies in malaria endemic countries and looks at the foreseeable challenges facing the establishment of NGS approaches for routine surveillance of parasite resistance to anti-malarials in SSA.
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Affiliation(s)
- Deus S Ishengoma
- National Institute for Medical Research, Tanga Centre, Tanga, Tanzania.
| | - Queen Saidi
- Kilimanjaro Christian Medical University College, Moshi, Tanzania
| | - Carol H Sibley
- Department of Genome Sciences, University of Washington, Seattle, USA
| | - Cally Roper
- London School of Hygiene & Tropical Medicine, London, UK
| | - Michael Alifrangis
- Centre for Medical Parasitology, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
- Department of Infectious Diseases, Copenhagen University Hospital, Copenhagen, Denmark
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