Declining efficacy of artemisinin combination therapy against P. falciparum malaria on the Thai-Myanmar border (2003-2013): The role of parasite genetic factors.
<h4>Background</h4> <p>Deployment of mefloquine–artesunate (MAS3) on the Thailand–Myanmar border has led to a sustained reduction in falciparum malaria, although antimalarial efficacy has declined substantially in recent years. The role of Plasmodium falciparum K13 mutations (a ma...
| मुख्य लेखकों: | , , , , , , , , , , , , , , , , , , , |
|---|---|
| स्वरूप: | Journal article |
| भाषा: | English |
| प्रकाशित: |
Oxford University Press
2016
|
| _version_ | 1826291918441545728 |
|---|---|
| author | Phyo, A Ashley, E Anderson, T Bozdech, Z Carrara, V Sriprawat, K Nair, S White, M Dziekan, J Ling, C Proux, S Konghahong, K Jeeyapant, A Woodrow, C Imwong, M McGready, R Lwin, K Day, N White, N Nosten, F |
| author_facet | Phyo, A Ashley, E Anderson, T Bozdech, Z Carrara, V Sriprawat, K Nair, S White, M Dziekan, J Ling, C Proux, S Konghahong, K Jeeyapant, A Woodrow, C Imwong, M McGready, R Lwin, K Day, N White, N Nosten, F |
| author_sort | Phyo, A |
| collection | OXFORD |
| description | <h4>Background</h4> <p>Deployment of mefloquine–artesunate (MAS3) on the Thailand–Myanmar border has led to a sustained reduction in falciparum malaria, although antimalarial efficacy has declined substantially in recent years. The role of Plasmodium falciparum K13 mutations (a marker of artemisinin resistance) in reducing treatment efficacy remains controversial.</p> <h4>Methods</h4> <p>Between 2003 and 2013, we studied the efficacy of MAS3 in 1005 patients with uncomplicated P. falciparum malaria in relation to molecular markers of resistance.</p> <h4>Results</h4> <p>Polymerase chain reaction (PCR)–adjusted cure rates declined from 100% in 2003 to 81.1% in 2013 as the proportions of isolates with multiple Pfmdr1 copies doubled from 32.4% to 64.7% and those with K13 mutations increased from 6.7% to 83.4%. K13 mutations conferring moderate artemisinin resistance (notably E252Q) predominated initially but were later overtaken by propeller mutations associated with slower parasite clearance (notably C580Y). Those infected with both multiple Pfmdr1 copy number and a K13 propeller mutation were 14 times more likely to fail treatment. The PCR-adjusted cure rate was 57.8% (95% confidence interval [CI], 45.4, 68.3) compared with 97.8% (95% CI, 93.3, 99.3) in patients with K13 wild type and Pfmdr1 single copy. K13 propeller mutation alone was a strong risk factor for recrudescence (P = .009). The combined population attributable fraction of recrudescence associated with K13 mutation and Pfmdr1 amplification was 82%.</p> <h4>Conclusions</h4> <p>The increasing prevalence of K13 mutations was the decisive factor for the recent and rapid decline in efficacy of artemisinin-based combination (MAS3) on the Thailand–Myanmar border.</p> |
| first_indexed | 2024-03-07T03:06:43Z |
| format | Journal article |
| id | oxford-uuid:b2cabe99-d401-4aa3-935f-05f3fcf7d90b |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T03:06:43Z |
| publishDate | 2016 |
| publisher | Oxford University Press |
| record_format | dspace |
| spelling | oxford-uuid:b2cabe99-d401-4aa3-935f-05f3fcf7d90b2022-03-27T04:14:19ZDeclining efficacy of artemisinin combination therapy against P. falciparum malaria on the Thai-Myanmar border (2003-2013): The role of parasite genetic factors.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:b2cabe99-d401-4aa3-935f-05f3fcf7d90bEnglishSymplectic Elements at OxfordOxford University Press2016Phyo, AAshley, EAnderson, TBozdech, ZCarrara, VSriprawat, KNair, SWhite, MDziekan, JLing, CProux, SKonghahong, KJeeyapant, AWoodrow, CImwong, MMcGready, RLwin, KDay, NWhite, NNosten, F <h4>Background</h4> <p>Deployment of mefloquine–artesunate (MAS3) on the Thailand–Myanmar border has led to a sustained reduction in falciparum malaria, although antimalarial efficacy has declined substantially in recent years. The role of Plasmodium falciparum K13 mutations (a marker of artemisinin resistance) in reducing treatment efficacy remains controversial.</p> <h4>Methods</h4> <p>Between 2003 and 2013, we studied the efficacy of MAS3 in 1005 patients with uncomplicated P. falciparum malaria in relation to molecular markers of resistance.</p> <h4>Results</h4> <p>Polymerase chain reaction (PCR)–adjusted cure rates declined from 100% in 2003 to 81.1% in 2013 as the proportions of isolates with multiple Pfmdr1 copies doubled from 32.4% to 64.7% and those with K13 mutations increased from 6.7% to 83.4%. K13 mutations conferring moderate artemisinin resistance (notably E252Q) predominated initially but were later overtaken by propeller mutations associated with slower parasite clearance (notably C580Y). Those infected with both multiple Pfmdr1 copy number and a K13 propeller mutation were 14 times more likely to fail treatment. The PCR-adjusted cure rate was 57.8% (95% confidence interval [CI], 45.4, 68.3) compared with 97.8% (95% CI, 93.3, 99.3) in patients with K13 wild type and Pfmdr1 single copy. K13 propeller mutation alone was a strong risk factor for recrudescence (P = .009). The combined population attributable fraction of recrudescence associated with K13 mutation and Pfmdr1 amplification was 82%.</p> <h4>Conclusions</h4> <p>The increasing prevalence of K13 mutations was the decisive factor for the recent and rapid decline in efficacy of artemisinin-based combination (MAS3) on the Thailand–Myanmar border.</p> |
| spellingShingle | Phyo, A Ashley, E Anderson, T Bozdech, Z Carrara, V Sriprawat, K Nair, S White, M Dziekan, J Ling, C Proux, S Konghahong, K Jeeyapant, A Woodrow, C Imwong, M McGready, R Lwin, K Day, N White, N Nosten, F Declining efficacy of artemisinin combination therapy against P. falciparum malaria on the Thai-Myanmar border (2003-2013): The role of parasite genetic factors. |
| title | Declining efficacy of artemisinin combination therapy against P. falciparum malaria on the Thai-Myanmar border (2003-2013): The role of parasite genetic factors. |
| title_full | Declining efficacy of artemisinin combination therapy against P. falciparum malaria on the Thai-Myanmar border (2003-2013): The role of parasite genetic factors. |
| title_fullStr | Declining efficacy of artemisinin combination therapy against P. falciparum malaria on the Thai-Myanmar border (2003-2013): The role of parasite genetic factors. |
| title_full_unstemmed | Declining efficacy of artemisinin combination therapy against P. falciparum malaria on the Thai-Myanmar border (2003-2013): The role of parasite genetic factors. |
| title_short | Declining efficacy of artemisinin combination therapy against P. falciparum malaria on the Thai-Myanmar border (2003-2013): The role of parasite genetic factors. |
| title_sort | declining efficacy of artemisinin combination therapy against p falciparum malaria on the thai myanmar border 2003 2013 the role of parasite genetic factors |
| work_keys_str_mv | AT phyoa decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors AT ashleye decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors AT andersont decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors AT bozdechz decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors AT carrarav decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors AT sriprawatk decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors AT nairs decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors AT whitem decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors AT dziekanj decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors AT lingc decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors AT prouxs decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors AT konghahongk decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors AT jeeyapanta decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors AT woodrowc decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors AT imwongm decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors AT mcgreadyr decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors AT lwink decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors AT dayn decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors AT whiten decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors AT nostenf decliningefficacyofartemisinincombinationtherapyagainstpfalciparummalariaonthethaimyanmarborder20032013theroleofparasitegeneticfactors |