cgp-56697 and artemisinin

Malaria in the first trimester of pregnancy is associated with adverse pregnancy outcomes. Artemisinin-based combination therapies (ACTs) are a highly effective, first-line treatment for uncomplicated Plasmodium falciparum malaria, except in the first trimester of pregnancy, when quinine with clindamycin is recommended due to concerns about the potential embryotoxicity of artemisinins. We compared adverse pregnancy outcomes after artemisinin-based treatment (ABT) versus non-ABTs in the first trimester of pregnancy.. For this systematic review and individual patient data (IPD) meta-analysis, we searched MEDLINE, Embase, and the Malaria in Pregnancy Library for prospective cohort studies published between Nov 1, 2015, and Dec 21, 2021, containing data on outcomes of pregnancies exposed to ABT and non-ABT in the first trimester. The results of this search were added to those of a previous systematic review that included publications published up until November, 2015. We included pregnancies enrolled before the pregnancy outcome was known. We excluded pregnancies with missing estimated gestational age or exposure information, multiple gestation pregnancies, and if the fetus was confirmed to be unviable before antimalarial treatment. The primary endpoint was adverse pregnancy outcome, defined as a composite of either miscarriage, stillbirth, or major congenital anomalies. A one-stage IPD meta-analysis was done by use of shared-frailty Cox models. This study is registered with PROSPERO, number CRD42015032371.. We identified seven eligible studies that included 12 cohorts. All 12 cohorts contributed IPD, including 34 178 pregnancies, 737 with confirmed first-trimester exposure to ABTs and 1076 with confirmed first-trimester exposure to non-ABTs. Adverse pregnancy outcomes occurred in 42 (5·7%) of 736 ABT-exposed pregnancies compared with 96 (8·9%) of 1074 non-ABT-exposed pregnancies in the first trimester (adjusted hazard ratio [aHR] 0·71, 95% CI 0·49-1·03). Similar results were seen for the individual components of miscarriage (aHR=0·74, 0·47-1·17), stillbirth (aHR=0·71, 0·32-1·57), and major congenital anomalies (aHR=0·60, 0·13-2·87). The risk of adverse pregnancy outcomes was lower with artemether-lumefantrine than with oral quinine in the first trimester of pregnancy (25 [4·8%] of 524 vs 84 [9·2%] of 915; aHR 0·58, 0·36-0·92).. We found no evidence of embryotoxicity or teratogenicity based on the risk of miscarriage, stillbirth, or major congenital anomalies associated with ABT during the first trimester of pregnancy. Given that treatment with artemether-lumefantrine was associated with fewer adverse pregnancy outcomes than quinine, and because of the known superior tolerability and antimalarial effectiveness of ACTs, artemether-lumefantrine should be considered the preferred treatment for uncomplicated P falciparum malaria in the first trimester. If artemether-lumefantrine is unavailable, other ACTs (except artesunate-sulfadoxine-pyrimethamine) should be preferred to quinine. Continued active pharmacovigilance is warranted.. Medicines for Malaria Venture, WHO, and the Worldwide Antimalarial Resistance Network funded by the Bill & Melinda Gates Foundation.

Topics: Abortion, Spontaneous; Antimalarials; Artemether; Artemether, Lumefantrine Drug Combination; Drug Combinations; Ethanolamines; Female; Humans; Malaria; Malaria, Falciparum; Pregnancy; Pregnancy Outcome; Pregnancy Trimester, First; Prospective Studies; Quinine; Stillbirth

Half of all pregnancies at risk of malaria worldwide occur in the Asia-Pacific region, where Plasmodium falciparum and Plasmodium vivax co-exist. Despite substantial reductions in transmission, malaria remains an important cause of adverse health outcomes for mothers and offspring, including pre-eclampsia. Malaria transmission is heterogeneous, and infections are commonly subpatent and asymptomatic. High-grade antimalarial resistance poses a formidable challenge to malaria control in pregnancy in the region. Intermittent preventive treatment in pregnancy reduces infection risk in meso-endemic New Guinea, whereas screen-and-treat strategies will require more sensitive point-of-care tests to control malaria in pregnancy. In the first trimester, artemether-lumefantrine is approved, and safety data are accumulating for other artemisinin-based combinations. Safety of novel antimalarials to treat artemisinin-resistant P falciparum during pregnancy, and of 8-aminoquinolines during lactation, needs to be established. A more systematic approach to the prevention of malaria in pregnancy in the Asia-Pacific is required.

Topics: Antimalarials; Artemether; Artemether, Lumefantrine Drug Combination; Artemisinins; Asia; Female; Humans; Lactation; Malaria; Malaria, Falciparum; Pregnancy

Malaria is a leading cause of death in children less than 5 years of age globally, and a common cause of fever in the returning North American traveler. New tools in the fight against malaria have been developed over the past decades: potent artemisinin derivatives; rapid diagnostic tests; long-lasting insecticidal bed nets; and a new vaccine, RTS,S/AS01. Thwarting these advances, parasite and Anopheles vector resistance are emerging. In the meantime, clinicians will continue to see malaria among febrile travelers from the tropics. Early recognition, diagnosis, and treatment can be lifesaving, but rely on the vigilance of frontline clinicians.

Topics: Acute Kidney Injury; Anemia; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Artesunate; Child; Child, Preschool; Female; Global Health; Humans; Infant; Malaria; Male; North America; Plasmodium; Respiratory Distress Syndrome; Travel

While significant advances have been made in the prevention and treatment of malaria in recent years, these successes continue to fall short of the World Health Organization (WHO) goals for malaria control and elimination. For elimination strategies to be effective, limited disease transmission, achieved through rapid reduction in the infectious parasite reservoir and decreased gametocyte carriage, will be critical. Artemisinin-based combination therapy (ACT) forms the cornerstone of WHO-recommended treatment for uncomplicated Plasmodium falciparum malaria, and in combination with other effective interventions will undoubtedly play a vital role in elimination programmes. The gametocytocidal properties of artemisinins are a bonus attribute; there is epidemiological evidence of reductions in malaria incidence and transmission in African regions since the introduction of these agents. Many studies and analyses have specifically investigated the effects of the ACT, artemether-lumefantrine (AL) on gametocyte carriage. In this systematic review of 62 articles published between 1998 and January 2014, the effects of AL on gametocyte carriage and malaria transmission are compared with other artemisinin-based anti-malarials and non-ACT. The impact of AL treatment of asymptomatic carriers on population gametocyte carriage, and the potential future role of AL in malaria elimination initiatives are also considered. Despite the inherent difficulties in comparing data from a range of different studies that also utilized different diagnostic approaches to assess baseline gametocyte counts, the gametocytocidal effect of AL was proportionately consistent across the studies reviewed, suggesting that AL will continue to play a vital role in the treatment of malaria and contribute to clearing the path towards malaria elimination. However, the specific place of AL is the subject of much ongoing research and will undoubtedly be dependent on different demographic and geographical scenarios. Utilizing ACT, such as AL, within malaria elimination strategies is also associated with a number of other challenges, such as balancing potential increased use of ACT (e g, treatment of asymptomatic carriers and home-based treatment) with rational use and avoidance of drug resistance development.

Topics: Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Drug Combinations; Ethanolamines; Fluorenes; Humans; Malaria, Falciparum; Plasmodium falciparum; Trophozoites

The purpose of the study was to compare the safety of artemether-lumefantrine (AL) with other artemisinin-based combinations in children.. A search of EMBASE (from 1974 to April 2013), MEDLINE (from 1946 to April 2013) and the Cochrane library of registered controlled trials for randomized controlled trials (RCTs) which compared AL with other artemisinin-based combinations was done. Only studies involving children ≤ 17 years old in which safety of AL was an outcome measure were included.. Four thousand, seven hundred and twenty six adverse events (AEs) were recorded in 6,000 patients receiving AL. Common AEs (≥ 1/100 and <1/10) included: coryza, vomiting, anaemia, diarrhoea, vomiting and abdominal pain; while cough was the only very commonly reported AE (≥ 1/10). AL-treated children have a higher risk of body weakness (64.9%) than those on artesunate-mefloquine (58.2%) (p = 0.004, RR: 1.12 95% CI: 1.04-1.21). The risk of vomiting was significantly lower in patients on AL (8.8%) than artesunate-amodiaquine (10.6%) (p = 0.002, RR: 0.76, 95% CI: 0.63-0.90). Similarly, children on AL had a lower risk of vomiting (1.2%) than chlorproguanil-dapsone-artesunate (ACD) treated children (5.2%) (p = 0.002, RR: 0.63, 95% CI: 0.47-0.85). The risk of serious adverse events was significantly lower for AL (1.3%) than ACD (5.2%) (p = 0.002, RR: 0.45, 95% CI: 0.27-0.74).. Artemether-lumefantrine combination is as safe as ASAQ and DP for use in children. Common adverse events are cough and gastrointestinal symptoms. More studies comparing AL with artesunate-mefloquine and artesunate-azithromycin are needed to determine the comparative safety of these drugs.

Topics: Adolescent; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Child; Child, Preschool; Cough; Drug Combinations; Drug-Related Side Effects and Adverse Reactions; Dyspepsia; Ethanolamines; Fluorenes; Humans; Infant; Infant, Newborn; Randomized Controlled Trials as Topic

This study examined the treatment response of mixed vs single-species Plasmodium falciparum infections to artemisinin-based combination therapies (ACTs).. A total of 1211 blood samples collected on days 0, 7, 14, 21, 28, 35, and 42 from 173 individuals enrolled in two randomized ACT efficacy studies were tested for malaria using 18s ribosomal RNA-based real-time polymerase chain reaction. All recurrent parasitemia were characterized for Plasmodium species composition and time to reinfection during 42-day follow-up compared across ACTs.. Day 0 samples had 71.1% (116/163) single P. falciparum infections and 28.2% (46/163) coinfections. A total of 54.0% (88/163) of individuals tested positive for Plasmodium at least once between days 7-42. A total of 19.3% (17/88) of individuals with recurrent infections were infected with a different Plasmodium species than observed at day 0, with 76.5% (13/17) of these "hidden" infections appearing after clearing P. falciparum present at day 0. Artesunate-mefloquine (16.4 hours) and dihydroartemisinin-piperaquine (17.6 hours) had increased clearance rates over artemether-lumefantrine (21.0 hours). Dihydroartemisinin-piperaquine exhibited the longest duration of reinfection prophylaxis. Cure rates were comparable across each species composition.. No differences in clearance rates were found depending on whether the infection contained species other than P. falciparum. Significantly longer durations of protection were observed for individuals treated with dihydroartemisinin-piperaquine.

Topics: Antimalarials; Artemether; Artemether, Lumefantrine Drug Combination; Artemisinins; Drug Combinations; Humans; Kenya; Malaria; Malaria, Falciparum; Plasmodium falciparum; Quinolines; Reinfection; Retrospective Studies

Malaria infection during pregnancy increases the risk of low birth weight and infant mortality and should be prevented and treated. Artemisinin-based combination treatments are generally well tolerated, safe and effective; the most used being artemether-lumefantrine (AL) and dihydroartemisinin-piperaquine (DP). Pyronaridine-artesunate (PA) is a new artemisinin-based combination. The main objective of this study is to determine the efficacy and safety of PA versus AL or DP when administered to pregnant women with confirmed. A phase 3, non-inferiority, randomised, open-label clinical trial to determine the safety and efficacy of AL, DP and PA in pregnant women with malaria in five sub-Saharan, malaria-endemic countries (Burkina Faso, Democratic Republic of the Congo, Mali, Mozambique and the Gambia). A total of 1875 pregnant women will be randomised to one of the treatment arms. Women will be actively monitored until Day 63 post-treatment, at delivery and 4-6 weeks after delivery, and infants' health will be checked on their first birthday. The primary endpoint is the PCR-adjusted rate of adequate clinical and parasitological response at Day 42 in the per-protocol population.. This protocol has been approved by the Ethics Committee for Health Research in Burkina Faso, the National Health Ethics Committee in the Democratic Republic of Congo, the Ethics Committee of the Faculty of Medicine and Odontostomatology/Faculty of Pharmacy in Mali, the Gambia Government/MRCG Joint Ethics Committee and the National Bioethics Committee for Health in Mozambique. Written informed consent will be obtained from each individual prior to her participation in the study. The results will be published in peer-reviewed open access journals and presented at (inter)national conferences and meetings.. PACTR202011812241529.

Topics: Antimalarials; Artemether; Artemether, Lumefantrine Drug Combination; Artemisinins; Clinical Trials, Phase III as Topic; Drug Combinations; Female; Humans; Infant; Malaria; Malaria, Falciparum; Pregnancy; Pregnant Women; Randomized Controlled Trials as Topic; Sub-Saharan African People; Treatment Outcome

Malaria significantly rebounded in 2018 in the Comoros; this created an urgent need to conduct clinical trials to investigate the effectiveness of artemisinin and its derivatives.. An open-label, non-randomised controlled trial of artemisinin-piperaquine (AP) and artemether-lumefantrine (AL) was conducted in Grande Comore island from June 2019 to January 2020. A total of 238 uncomplicated falciparum malaria cases were enrolled and divided 1:1 into two treatments. The primary endpoint was the 42-day adequate clinical and parasitological responses (ACPR). Secondary endpoints were parasitaemia and fever clearance at day 3, gametocytes and tolerability.. The 42-day ACPR before and after PCR correction were 91.43% (95% CI 83.93-95.76%) and 98.06% (95% CI 92.48-99.66%) for AP treatment, respectively, and 96.00% (95% CI 88.17-98.14%) and 98.97% (95% CI 93.58-99.95%) for AL treatment, respectively. Complete clearance of the parasitaemia and fever for both groups was detected on day 3. Gametocytes disappeared on day 21 in the AP group and on day 2 in AL group. Specifically, the adverse reactions were mild in both groups.. It was found that AP and AL maintained their high efficacy and tolerance in the Comoros. Nonetheless, asymptomatic malaria infections bring new challenges to malaria control.

Topics: Antimalarials; Artemether; Artemether, Lumefantrine Drug Combination; Artemisinins; Drug Combinations; Ethanolamines; Fluorenes; Humans; Malaria; Malaria, Falciparum; Piperazines; Plasmodium falciparum; Quinolines

Primaquine is an important gametocytocidal drug that is combined with conventional malaria treatment for prevention of Plasmodium falciparum malaria transmission. Primaquine has been administered together on the first or the last day of conventional treatment but the impact of primaquine timing has never been examined. This study aimed to assess safety, efficacy and optimal timing of single full-dose (0.75 mg/kg) primaquine when added to a standard 6-dose regimen of artemether-lumefantrine (AL).. In an individual-level randomized controlled trial, enrolled participants who were G6PD normal and had uncomplicated P. falciparum malaria were randomly assigned to receive: AL only; AL and a single 0.75 mg/kg primaquine dose on the first day of AL (day 1); or AL and single 0.75 mg//kg primaquine on the last day of AL (day 3). On days 2, 3, 4, 8, 11 and 15, gametocytes were assessed and quantified by microscope and quantitative nuclear acid sequence based quantification (QT-NASBA).. Overall, 111 participants aged between 3 and 17 years were randomly allocated to receive AL only (36) or combined with primaquine on day 1 (38), or primaquine on day 3 (37). Day 4 gametocyte prevalence in AL + day 1 primaquine was half the level seen in either AL + day 3 primaquine or AL only arm (11% [4/35] vs 26% [8/31] and 27% [8/30], respectively) albeit not statistically significant. A similar trend of lower gametocyte in the AL + day 1 primaquine verses AL + day 3 primaquine or AL only arm was observed in mean gametocyte density. Mean (sd) haemoglobin level in AL + day 3 primaquine arm recovered from -0.42(1.2) g/dl on day 2 to 0.35 (1.5) g/dl on day 15 of follow up. This was not the case in AL only and AL + day 1 primaquine arms during the same follow-up period, although the difference was not statistically significant (p = 318). No serious adverse events reported in the study. Across arms, 23% (26/111) of participants reported a total of 31 mild adverse events and the difference was not statistically significant (p = 0.477).. Primaquine administration on the first day of AL is well tolerated and as safe as later administration. Whilst the World Health Organization currently recommends a lower dose of primaquine (0.25 mg/kg), the findings are supportive of early primaquine administration when combined with artemisinin-combination therapy. ClinicalTrials.gov Registration NCT01906788.

Topics: Adolescent; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Carrier State; Child; Child, Preschool; Drug Therapy, Combination; Female; Hemoglobins; Humans; Malaria, Falciparum; Male; Plasmodium falciparum; Primaquine; Time Factors

Artemisinin and partner-drug resistance in Plasmodium falciparum are major threats to malaria control and elimination. Triple artemisinin-based combination therapies (TACTs), which combine existing co-formulated ACTs with a second partner drug that is slowly eliminated, might provide effective treatment and delay emergence of antimalarial drug resistance.. In this multicentre, open-label, randomised trial, we recruited patients with uncomplicated P falciparum malaria at 18 hospitals and health clinics in eight countries. Eligible patients were aged 2-65 years, with acute, uncomplicated P falciparum malaria alone or mixed with non-falciparum species, and a temperature of 37·5°C or higher, or a history of fever in the past 24 h. Patients were randomly assigned (1:1) to one of two treatments using block randomisation, depending on their location: in Thailand, Cambodia, Vietnam, and Myanmar patients were assigned to either dihydroartemisinin-piperaquine or dihydroartemisinin-piperaquine plus mefloquine; at three sites in Cambodia they were assigned to either artesunate-mefloquine or dihydroartemisinin-piperaquine plus mefloquine; and in Laos, Myanmar, Bangladesh, India, and the Democratic Republic of the Congo they were assigned to either artemether-lumefantrine or artemether-lumefantrine plus amodiaquine. All drugs were administered orally and doses varied by drug combination and site. Patients were followed-up weekly for 42 days. The primary endpoint was efficacy, defined by 42-day PCR-corrected adequate clinical and parasitological response. Primary analysis was by intention to treat. A detailed assessment of safety and tolerability of the study drugs was done in all patients randomly assigned to treatment. This study is registered at ClinicalTrials.gov, NCT02453308, and is complete.. Between Aug 7, 2015, and Feb 8, 2018, 1100 patients were given either dihydroartemisinin-piperaquine (183 [17%]), dihydroartemisinin-piperaquine plus mefloquine (269 [24%]), artesunate-mefloquine (73 [7%]), artemether-lumefantrine (289 [26%]), or artemether-lumefantrine plus amodiaquine (286 [26%]). The median age was 23 years (IQR 13 to 34) and 854 (78%) of 1100 patients were male. In Cambodia, Thailand, and Vietnam the 42-day PCR-corrected efficacy after dihydroartemisinin-piperaquine plus mefloquine was 98% (149 of 152; 95% CI 94 to 100) and after dihydroartemisinin-piperaquine was 48% (67 of 141; 95% CI 39 to 56; risk difference 51%, 95% CI 42 to 59; p<0·0001). Efficacy of dihydroartemisinin-piperaquine plus mefloquine in the three sites in Myanmar was 91% (42 of 46; 95% CI 79 to 98) versus 100% (42 of 42; 95% CI 92 to 100) after dihydroartemisinin-piperaquine (risk difference 9%, 95% CI 1 to 17; p=0·12). The 42-day PCR corrected efficacy of dihydroartemisinin-piperaquine plus mefloquine (96% [68 of 71; 95% CI 88 to 99]) was non-inferior to that of artesunate-mefloquine (95% [69 of 73; 95% CI 87 to 99]) in three sites in Cambodia (risk difference 1%; 95% CI -6 to 8; p=1·00). The overall 42-day PCR-corrected efficacy of artemether-lumefantrine plus amodiaquine (98% [281 of 286; 95% CI 97 to 99]) was similar to that of artemether-lumefantrine (97% [279 of 289; 95% CI 94 to 98]; risk difference 2%, 95% CI -1 to 4; p=0·30). Both TACTs were well tolerated, although early vomiting (within 1 h) was more frequent after dihydroartemisinin-piperaquine plus mefloquine (30 [3·8%] of 794) than after dihydroartemisinin-piperaquine (eight [1·5%] of 543; p=0·012). Vomiting after artemether-lumefantrine plus amodiaquine (22 [1·3%] of 1703) and artemether-lumefantrine (11 [0·6%] of 1721) was infrequent. Adding amodiaquine to artemether-lumefantrine extended the electrocardiogram corrected QT interval (mean increase at 52 h compared with baseline of 8·8 ms [SD 18·6] vs 0·9 ms [16·1]; p<0·01) but adding mefloquine to dihydroartemisinin-piperaquine did not (mean increase of 22·1 ms [SD 19·2] for dihydroartemisinin-piperaquine vs 20·8 ms [SD 17·8] for dihydroartemisinin-piperaquine plus mefloquine; p=0·50).. Dihydroartemisinin-piperaquine plus mefloquine and artemether-lumefantrine plus amodiaquine TACTs are efficacious, well tolerated, and safe treatments of uncomplicated P falciparum malaria, including in areas with artemisinin and ACT partner-drug resistance.. UK Department for International Development, Wellcome Trust, Bill & Melinda Gates Foundation, UK Medical Research Council, and US National Institutes of Health.

Topics: Adolescent; Adult; Amodiaquine; Anthraquinones; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Drug Resistance; Drug Therapy, Combination; Female; Humans; Malaria, Falciparum; Male; Mefloquine; Plasmodium falciparum; Polymerase Chain Reaction; Quinolines; Treatment Outcome; Young Adult

Artemisinin-based combination treatments (ACTs) or intravenous artesunate are used in over 100 countries for uncomplicated or severe falciparum malaria. Although intravenous artesunate may cause delayed haemolytic anaemia, there is little evaluation of the temporal changes in haematocrit following ACTs.. Clinical and parasitological parameters were measured before and following treatment of uncomplicated falciparum malaria in children with artesunate-amodiaquine (AA) or artemether-lumefantrine (AL) over 6-weeks. Changes in haematocrit were characterized in individual patients based on a haematocrit <30 % or ≥30 % before and following treatment. Kinetics of the deficit in haematocrit from <30 % until attainment of ≥30 % were estimated by a non-compartment model.. In 248 of 1180 children eligible for evaluation, common temporal patterns were: no change or increase in haematocrit from ≥ 30 % [50 % of patients], haematocrit >30 % at presentation declining to <30 % within 2 weeks (early monophasic fall) [19 % of patients], and haematocrit <30 % at presentation increasing to ≥ 30 % [23 % of patients]. Haematocrit >30 % at presentation declining to <30 %, 3-5 weeks later (late monophasic fall) occurred in 7 children (3 %). Fall in haematocrit ≥5 units following treatment occurred in 57 children [23 %] between 14 and 28 days after treatment began. Baseline parasitaemia and proportion with > 100,000μL(-1) asexual forms were significantly higher in children with ≥5 units compared to <5 units fall in haematocrit 21 or 28 days after treatment began. Irrespective of pattern, declines in haematocrit deficit from <30 % were mono-exponential, with similar half-times for AA- and AL-treated children (1.32 d versus 1.14 d). Anaemia half-time correlated significantly positively with anaemia recovery time in the same patients (r = 0.55, P < 0.0001). Bland-Altman analysis of 9 or 10 multiples of anaemia half-time and anaemia recovery times showed narrow limit of agreement with insignificant biases (P = 0.19 or 0.63, respectively).. In uncomplicated falciparum malaria, increases or falls in haematocrit are common following ACTs. Falls in haematocrit ≥ 5 units are common and may or may not result in early or late anaemia. In children who recovered from acute falciparum malaria-associated anaemia following ACTs, decline in haematocrit deficit is mono-exponential.. Pan African Clinical Trial Registry PACTR201508001188143 , 3 July 2015; PACTR201508001191898 , 7 July 2015 http://www.pactr.org .

Topics: Administration, Intravenous; Adolescent; Amodiaquine; Anemia; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Child; Child, Preschool; Combined Modality Therapy; Drug Combinations; Drug Therapy, Combination; Ethanolamines; Female; Fluorenes; Hematocrit; Humans; Infant; Malaria, Falciparum; Male; Prospective Studies; Treatment Outcome

The efficacy of 3-day regimens of artemether-lumefantrine and artesunate-amodiaquine were evaluated in 747 children < 5 years of age with uncomplicated malaria from six geographical areas of Nigeria. Fever clearance was significantly faster (P = 0.006) and the proportion of children with parasitemia 1 day after treatment began was significantly lower (P = 0.016) in artesunate-amodiaquine-compared with artemether-lumefantrine-treated children. Parasite clearance times were similar with both treatments. Overall efficacy was 96.3% (95% confidence interval [CI] 94.5-97.6%), and was similar for both regimens. Polymerase chain reaction-corrected parasitologic cure rates on Day 28 were 96.9% (95% CI 93.9-98.2%) and 98.3% (95% CI 96.1-99.3%) for artemether-lumefantrine and artesunate-amodiaquine, respectively. Gametocyte carriage post treatment was significantly lower than pretreatment (P < 0.0001). In anemic children, mean time to recovery from anemia was 10 days (95% CI 9.04-10.9) and was similar for both regimens. Both treatments were well tolerated and are safe and efficacious treatments of uncomplicated falciparum malaria in young Nigerian children.

Topics: Amodiaquine; Anemia; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Child, Preschool; Drug Combinations; Ethanolamines; Female; Fluorenes; Humans; Malaria, Falciparum; Male; Nigeria; Parasitemia; Prevalence; Treatment Outcome

Artemisinin-based combination therapy is currently recommended by the World Health Organization as first-line treatment of uncomplicated malaria. Recommendations were adapted in 2010 regarding rescue treatment in case of treatment failure. Instead of quinine monotherapy, it should be combined with an antibiotic with antimalarial properties; alternatively, another artemisinin-based combination therapy may be used. However, for informing these policy changes, no clear evidence is yet available. The need to provide the policy makers with hard data on the appropriate rescue therapy is obvious. We hypothesize that the efficacy of the same artemisinin-based combination therapy used as rescue treatment is as efficacious as quinine + clindamycin or an alternative artemisinin-based combination therapy, without the risk of selecting drug resistant strains.. We embed a randomized, open label, three-arm clinical trial in a longitudinal cohort design following up children with uncomplicated malaria until they are malaria parasite free for 4 weeks. The study is conducted in both the Democratic Republic of Congo and Uganda and performed in three steps. In the first step, the pre-randomized controlled trial (RCT) phase, children aged 12 to 59 months with uncomplicated malaria are treated with the recommended first-line drug and constitute a cohort that is passively followed up for 42 days. If the patients experience an uncomplicated malaria episode between days 14 and 42 of follow-up, they are randomized either to quinine + clindamycin, or an alternative artemisinin-based combination therapy, or the same first-line artemisinin-based combination therapy to be followed up for 28 additional days. If between days 14 and 28 the patients experience a recurrent parasitemia, they are retreated with the recommended first-line regimen and actively followed up for another 28 additional days (step three; post-RCT phase). The same methodology is followed for each subsequent failure. In any case, all patients without an infection at day 28 are classified as treatment successes and reach a study endpoint. The RCT phase allows the comparison of the safety and efficacy of three rescue treatments. The prolonged follow-up of all children until they are 28 days parasite-free allows us to assess epidemiological-, host- and parasite-related predictors for repeated malaria infection.. NCT01374581 and PACTR201203000351114.

Topics: Amodiaquine; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Child, Preschool; Clindamycin; Clinical Protocols; Democratic Republic of the Congo; Drug Combinations; Drug Resistance; Drug Therapy, Combination; Ethanolamines; Female; Fluorenes; Humans; Incidence; Infant; Longitudinal Studies; Malaria, Falciparum; Male; Plasmodium falciparum; Quinine; Recurrence; Research Design; Retreatment; Time Factors; Treatment Outcome; Uganda

We conducted an open-label, randomized clinical trial to assess parasite clearance times (PCT) and the efficacy of 4 mg/kg (group 1, n = 22) and 2 mg/kg (group 2, n = 22) of oral artesunate for three days followed by artemether-lumefantrine in patients with uncomplicated Plasmodium falciparum malaria at Xepon Interdistrict Hospital, Savannakhet Province in southern Laos. Slides were read in duplicate. The overall mean (95% confidence interval; range) PCT in hours was 23.2 (21.2-25.3; 12-46) and 22.4 (20.3-24.5; 12-46) for the first and second microscopists, respectively (P = 0.57). Ten (23%) patients remained parasitemic on day 1 after treatment (4 [18%] in group 1 and 6 [27%] in group 2; P = 0.47). No patient had patent asexual parasitemia on the second and third days of treatment. The 42-day polymerase chain reaction-corrected cure rates were 100% in both treatment groups. Serious adverse events did not develop during or after treatment in any patients. In conclusion, no evidence of P. falciparum in vivo resistance to artesunate was found in southern Laos.

Topics: Administration, Oral; Adolescent; Adult; Aged; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Artesunate; Child; Drug Combinations; Drug Resistance; Drug Therapy, Combination; Ethanolamines; Female; Fluorenes; Follow-Up Studies; Humans; Laos; Malaria, Falciparum; Male; Middle Aged; Plasmodium falciparum; Treatment Outcome; Young Adult

Combination therapy with artemesinin or non-artemesinin-based antimalarials (ACTs or NACTs) are known to retard the development and progression of drug resistance in Plasmodium falciparum (P. falciparum). The optimal antimalarial combinations in Africa are yet unknown. We evaluate the therapeutic efficacy and effects on gametocyte carriage of Artemether-Lumefantrine (AL) and Amodiaquine-Sulfalene/Pyrimethamine (ASP) in children with P. falciparum malaria in an endemic area. One-hundred and thirty-nine children aged ≤ 10 years with uncomplicated P. falciparum malaria were enrolled. The primary end points were adequate clinical and parasitological response (ACPR), late parasitological failure(LPF), late clinical failure (LCF) and early treatment failure (ETF). Polymerase chain reaction (PCR)-corrected cure rates on days 14-42 and gametocyte carriage rates were determined. Fever clearance time was significantly shorter (P = 0.009) with ASP, but parasite clearance time was similar with both regimens. Day 28 cure rates were 91.4 and 89.9% (PCR-corrected) for AL and ASP respectively. Both regimens were well tolerated. Overall, gametocyte carriage before and following treatment were similar. Both combinations were found effective and comparable for treatment of acute, uncomplicated, P. falciparum malaria.

Topics: Amodiaquine; Antimalarials; Artemether; Artemether, Lumefantrine Drug Combination; Artemisinins; Child, Preschool; Chloroquine; Drug Combinations; Drug Resistance; Drug Therapy, Combination; Ethanolamines; Female; Fluorenes; Follow-Up Studies; Gametogenesis; Humans; Infant; Lumefantrine; Malaria, Falciparum; Male; Nigeria; Plasmodium falciparum; Polymerase Chain Reaction; Pyrimethamine; Sulfalene; Treatment Outcome

Drug resistance in Plasmodium falciparum poses a major threat to malaria control. Combination anti-malarial therapy, including artemisinins, has been advocated to improve efficacy and limit the spread of resistance. The fixed combination of oral artemether-lumefantrine (AL) is highly effective and well-tolerated. Artemisinin/naphtoquine (AN) is a fixed-dose ACT that has recently become available in Africa. The objectives of the study were to compare the efficacy and safety of AN and AL for the treatment of uncomplicated falciparum malaria in a high transmission-intensity site in Ivory Coast.. We enrolled 122 participants aged 6 months or more with uncomplicated falciparum malaria. Participants were randomized to receive either artemisinin/naphtoquine or artemether/lumefantrine with variable dose according to their weight. Primary endpoints were the risks of treatment failure within 28 days, either unadjusted or adjusted by genotyping to distinguish recrudescence from new infection.. Among 125 participants enrolled, 123 (98.4%) completed follow-up. Clinical evaluation of the 123 participants showed that cumulative PCR-uncorrected cure rate on day 28 was 100% for artemisinin/naphtoquine and 98.4% for artemether/lumefantrine. Both artemisinin-based combinations effected rapid fever and parasite clearance.. These data suggest that Arco could prove to be suitable for use as combination antimalarial therapy. Meanwhile, pharmacokinetic studies and further efficacy assessment should be conducted before its widespread use can be supported.

Topics: Adult; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Child; Cote d'Ivoire; Drug Administration Schedule; Drug Combinations; Drug Therapy, Combination; Ethanolamines; Female; Fluorenes; Follow-Up Studies; Humans; Malaria, Falciparum; Male; Plasmodium falciparum; Polymerase Chain Reaction; Recurrence; Treatment Outcome

The Home Management of Malaria (HMM) strategy was developed using chloroquine, a now obsolete drug, which has been replaced by artemisinin-based combination therapy (ACT) in health facility settings. Incorporation of ACT in HMM would greatly expand access to effective antimalarial therapy by the populations living in underserved areas in malaria endemic countries. The feasibility and acceptability of incorporating ACT in HMM needs to be evaluated.. A multi-country study was performed in four district-size sites in Ghana (two sites), Nigeria and Uganda, with populations ranging between 38,000 and 60,000. Community medicine distributors (CMDs) were trained in each village to dispense pre-packaged ACT to febrile children aged 6-59 months, after exclusion of danger signs. A community mobilization campaign accompanied the programme. Artesunate-amodiaquine (AA) was used in Ghana and artemether-lumefantrine (AL) in Nigeria and Uganda. Harmonized qualitative and quantitative data collection methods were used to evaluate CMD performance, caregiver adherence and treatment coverage of febrile children with ACTs obtained from CMDs.. Some 20,000 fever episodes in young children were treated with ACT by CMDs across the four study sites. Cross-sectional surveys identified 2,190 children with fever in the two preceding weeks, of whom 1,289 (59%) were reported to have received ACT from a CMD. Coverage varied from 52% in Nigeria to 75% in Ho District, Ghana. Coverage rates did not appear to vary greatly with the age of the child or with the educational level of the caregiver. A very high proportion of children were reported to have received the first dose on the day of onset or the next day in all four sites (range 86-97%, average 90%). The proportion of children correctly treated in terms of dose and duration was also high (range 74-97%, average 85%). Overall, the proportion of febrile children who received prompt treatment and the correct dose for the assigned duration of treatment ranged from 71% to 87% (average 77%). Almost all caregivers perceived ACT to be effective, and no severe adverse events were reported.. ACTs can be successfully integrated into the HMM strategy.

Topics: Amodiaquine; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Child, Preschool; Drug Combinations; Ethanolamines; Feasibility Studies; Fever; Fluorenes; Ghana; Humans; Infant; Malaria; Nigeria; Patient Acceptance of Health Care; Treatment Outcome; Uganda

Artemisinin-based combination therapies (ACTs) are the primary treatment for malaria. It is essential to characterize the pharmacokinetics (PKs) and pharmacodynamics (PDs) of ACTs in vulnerable populations at risk of suboptimal dosing. We developed a population PK/PD model using data from our previous study of artemether-lumefantrine in HIV-uninfected and HIV-infected children living in a high-transmission region of Uganda. HIV-infected children were on efavirenz-, nevirapine-, or lopinavir-ritonavir-based antiretroviral regimens, with daily trimethoprim-sulfamethoxazole prophylaxis. We assessed selection for resistance in two key parasite transporters, pfcrt and pfmdr1, over 42-day follow-up and incorporated genotyping into a time-to-event model to ascertain how resistance genotype in relation to drug exposure impacts recurrence risk. Two hundred seventy-seven children contributed 364 episodes to the model (186 HIV-uninfected and 178 HIV-infected), with recurrent microscopy-detectable parasitemia detected in 176 episodes by day 42. The final model was a two-compartment model with first-order absorption and an estimated age effect on bioavailability. Systemic lumefantrine exposure was highest with lopinavir-ritonavir, lowest with efavirenz, and equivalent with nevirapine and HIV-uninfected children. HIV status and lumefantrine concentration were significant factors associated with recurrence risk. Significant selection was demonstrated for pfmdr1 N86 and pfcrt K76 in recurrent infections, with no evidence of selection for pfmdr1 Y184F. Less sensitive parasites were able to tolerate lumefantrine concentrations ~ 3.5-fold higher than more sensitive parasites. This is the first population PK model of lumefantrine in HIV-infected children and demonstrates selection for reduced lumefantrine susceptibility, a concern as we confront the threat to ACTs posed by emerging artemisinin resistance in Africa.

Topics: Antimalarials; Artemether; Artemether, Lumefantrine Drug Combination; Artemisinins; Child; Drug Combinations; Fluorenes; HIV Infections; Humans; Lopinavir; Lumefantrine; Malaria; Malaria, Falciparum; Nevirapine; Ritonavir; Uganda

Artemisinin-based combination therapy (ACT) is the first-line treatment for uncomplicated malaria in Ghana. Artemisinin (ART) tolerance in Plasmodium falciparum has arisen in Southeast Asia and recently, in parts of East Africa. This is ascribed to the survival of ring-stage parasites post treatment. The present study sought to assess and characterize correlates of potential ART tolerance based on post-treatment parasite clearance, ex vivo and in vitro drug sensitivity, and molecular markers of drug resistance in P. falciparum isolates from children with uncomplicated malaria in Ghana.. The observed low proportion of participants with day-3 post-treatment parasitaemia is consistent with rapid ART clearance. However, the increased rates of survival observed in the ex vivo RSA against DHA, maybe a pointer of an early start of ART tolerance. Furthermore, the role of two novel mutations in PfK13 and Pfcoronin genes, harboured by the two RSA positive isolates that had high ring survival in the present study, remains to be elucidated.

Topics: Antimalarials; Artemether; Artemether, Lumefantrine Drug Combination; Artemisinins; Child; Drug Combinations; Drug Tolerance; Ghana; Humans; Lumefantrine; Malaria; Malaria, Falciparum; Plasmodium falciparum

Malaria is endemic in 95% of Uganda and constitutes the country's most significant public health problem-being the leading cause of morbidity and mortality, especially among children under five years of age. The current national malaria treatment policy is to use artemisinin-based combination therapy (ACT) as first-line treatment, and recommends parasitological confirmation of malaria before therapy. Adherence to this policy, however, remains suboptimal, with the self-initiated home-based therapy being common-posing undue exposures to, and pressure on the current artemisinin-based combinations, with the danger of emergence of drug resistance. The study evaluated the anti-malarial use and its appropriateness among febrile children under five presenting to a tertiary health facility in northern Uganda in light of the current malaria treatment policy.. This was a cross-sectional study in a tertiary health facility in northern Uganda between March and September 2021. Children aged 6-59 months with fever were selected using systematic random sampling. A pretested interviewer-administered questionnaire was used to collect clinical data from the caregivers. Data were analysed using SPSS version 23. Descriptive statistics and multiple logistic regression models were applied. P-value < 0.05 was considered for statistical significance.. Seventy-two (34.3%) of the 210 children with fever in this study used anti-malarials prior to the hospital visit, 29.2% (21/72) of which were on a self-medication basis, 22.2% (16/72) were empiric prescriptions-all of which inappropriate, and only 48.6% (35/72) were prescribed based on a parasitological diagnosis of malaria. The most commonly used anti-malarials were artemether-lumefantrine 60/72 (88.3%), while a lesser proportion of quinine 7/72 (9.7%), artesunate 3/72 (4.2%) and dihydroartemisinin-piperaquine 2/72 (2.8%) were used. The factors independently associated with anti-malarial use among the children with febrile illnesses were duration of fever (p = 0.001); level of the nearest facility (p = 0.027), distance from the nearest health facility (p = 0.025), and caregivers' age (p = 0.038).. Inappropriate use of anti-malarials for childhood febrile illnesses is prevalent in the study setting, facilitated by the ease of over-the-counter access, empiric prescription and use of leftover anti-malarials. This calls for a need to address communities' health-seeking behaviour and the health providers' practice alike.

Topics: Antimalarials; Artemether; Artemether, Lumefantrine Drug Combination; Artemisinins; Child; Child, Preschool; Cross-Sectional Studies; Fever; Humans; Malaria

Increasing levels of artemisinin and partner drug resistance threaten malaria control and elimination globally. Triple artemisinin-based combination therapies (TACTs) which combine artemisinin derivatives with two partner drugs are efficacious and well tolerated in clinical trials, including in areas of multidrug-resistant malaria. Whether early TACT adoption could delay the emergence and spread of antimalarial drug resistance is a question of vital importance. Using two independent individual-based models of Plasmodium falciparum epidemiology and evolution, we evaluated whether introduction of either artesunate-mefloquine-piperaquine or artemether-lumefantrine-amodiaquine resulted in lower long-term artemisinin-resistance levels and treatment failure rates compared with continued ACT use. We show that introduction of TACTs could significantly delay the emergence and spread of artemisinin resistance and treatment failure, extending the useful therapeutic life of current antimalarial drugs, and improving the chances of malaria elimination. We conclude that immediate introduction of TACTs should be considered by policy makers in areas of emerging artemisinin resistance.

Topics: Antimalarials; Artemether; Artemether, Lumefantrine Drug Combination; Artemisinins; Folic Acid Antagonists

Artesunate-amodiaquine (AS-AQ) and artemether-lumefantrine (AL) are the currently recommended first-and second-line therapies for uncomplicated Plasmodium falciparum infections in Chad. This study assessed the efficacy of these artemisinin-based combinations, proportion of day 3 positive patients, proportions of molecular markers associated with P. falciparum resistance to anti-malarial drugs and variable performance of HRP2-based malaria rapid diagnostic tests (RDTs).. A single-arm prospective study assessing the efficacy of AS-AQ and AL at three sites (Doba, Kelo and Koyom) was conducted between November 2020 to January 2021. Febrile children aged 6 to 59 months with confirmed uncomplicated P. falciparum infection were enrolled sequentially first to AS-AQ and then AL at each site and followed up for 28 days. The primary endpoint was PCR-adjusted adequate clinical and parasitological response (ACPR). Samples collected on day 0 were analysed for mutations in pfkelch13, pfcrt, pfmdr-1, pfdhfr, pfdhps genes and deletions in pfhrp2/pfhrp3 genes.. By the end of 28-day follow-up, per-protocol PCR corrected ACPR of 97.8% (CI 95% 88.2-100) in Kelo and 100% in Doba and Kayoma were observed among AL treated patients. For ASAQ, 100% ACPR was found in all sites. All, but one patient, did not have parasites detected on day 3. Out of the 215 day 0 samples, 96.7% showed pfkelch13 wild type allele. Seven isolates carried nonsynonymous mutations not known to be associated artemisinin partial resistance (ART-R). Most of samples had a pfcrt wild type allele (79% to 89%). The most prevalent pfmdr-1 allele detected was the single mutant 184F (51.2%). For pfdhfr and pfdhps mutations, the quintuple mutant allele N51I/C59R/S108N + G437A/540E responsible for SP treatment failures in adults and children was not detected. Single deletion in the pfhrp2 and pfhrp3 gene were detected in 10/215 (4.7%) and 2/215 (0.9%), respectively. Dual pfhrp2/pfhrp3 deletions, potentially threatening the efficacy of HRP2-based RDTs, were observed in 5/215 (2.3%) isolates.. The results of this study confirm that AS-AQ and AL treatments are highly efficacious in study areas in Chad. The absence of known pfkelch13 mutations in the study sites and the high parasite clearance rate at day 3 suggest the absence of ART-R. The absence of pfdhfr/pfdhps quintuple or sextuple (quintuple + 581G) mutant supports the continued use of SP for IPTp during pregnancy. The presence of parasites with dual pfhrp2/pfhrp3 deletions, potentially threatening the efficacy of HRP2-based RDTs, warrants the continued surveillance. Trial registration ACTRN12622001476729.

Topics: Adult; Amodiaquine; Antimalarials; Artemether; Artemether, Lumefantrine Drug Combination; Artemisinins; Artesunate; Chad; Female; Humans; Malaria, Falciparum; Pregnancy; Prospective Studies

Concerns about emerging resistance to artemether-lumefantrine (AL) in Africa prompted the pilot introduction of multiple first-line therapies (MFT) in Western Kenya, potentially exposing women-of-childbearing-age (WOCBA) to anti-malarials with unknown safety profiles in the first trimester. The study assessed healthcare provider knowledge and adherence to national guidelines for managing malaria in pregnancy in the context of the MFT pilot.. From March to April 2022, a cross-sectional study was conducted in 50 health facilities (HF) and 40 drug outlets (DO) using structured questionnaires to assess pregnancy detection, malaria diagnosis, and treatment choices by trimester. Differences between HF and DO providers and between MFT and non-MFT HFs were assessed using Chi-square tests.. Of 174 providers (77% HF, 23% DO), 56% were from MFT pilot facilities. Most providers had tertiary education; 5% HF and 20% DO had only primary or secondary education. More HF than DO providers had knowledge of malaria treatment guidelines (62% vs. 40%, p = 0.023), received training in malaria in pregnancy (49% vs. 20%, p = 0.002), and reported assessing for pregnancy in WOCBA (98% vs. 78%, p < 0.001). Most providers insisted on parasitological diagnosis, with 59% HF using microscopy and 85% DO using rapid diagnostic tests. More HF than DO providers could correctly name the drugs for treating uncomplicated malaria in the first trimester (oral quinine, or AL if quinine is unavailable) (90% vs. 58%, p < 0.001), second and third trimesters (artemisinin-based combination therapy) (84% vs. 70%, p = 0.07), and for severe malaria (parenteral artesunate/artemether) (94% vs. 60%, p < 0.001). Among HF providers, those in the MFT pilot had more knowledge of malaria treatment guidelines (67% vs. 49%, p = 0.08) and had received training on treatment of malaria in pregnancy (56% vs. 32%, p = 0.03). Few providers (10% HF and 12% DO) had adequate knowledge of malaria treatment in pregnancy, defined as the correct drug and dose for uncomplicated and severe malaria in all trimesters.. Knowledge of national malaria in pregnancy treatment guidelines among providers in Western Kenya is suboptimal. Robust training on appropriate anti-malarial and dosage is needed, particularly given the recent change in recommendation for artemether-lumefantrine use in the first trimester. Supervision of DO and HF practices is essential for correct treatment of malaria in pregnancy in the context of MFT programmes.

Topics: Antimalarials; Artemether; Artemether, Lumefantrine Drug Combination; Artemisinins; Case Management; Cross-Sectional Studies; Female; Humans; Kenya; Malaria; Pregnancy; Quinine

Partial artemisinin resistance is suspected if delayed parasite clearance (ie, persistence of parasitaemia on day 3 after treatment initiation) is observed. Validated markers of artemisinin partial resistance in southeast Asia, Plasmodium falciparum kelch13 (Pfkelch13) R561H and P574L, have been reported in Rwanda but no association with parasite clearance has been observed. We aimed to establish the efficacy of artemether-lumefantrine and genetic characterisation of Pfkelch13 alleles and their association with treatment outcomes.. This open-label, single-arm, multicentre, therapeutic efficacy study was done in 2018 in three Rwandan sites: Masaka, Rukara, and Bugarama. Children aged 6-59 months with P falciparum monoinfection and fever were eligible and treated with a 3-day course of artemether-lumefantrine. Treatment response was monitored for 28 days using weekly microscopy screenings of blood samples for P falciparum. Mutations in Pfkelch13 and P falciparum multidrug resistance-1 (Pfmdr1) genes were characterised in parasites collected from enrolled participants. Analysis of flanking microsatellites surrounding Pfkelch13 was done to define the origins of the R561H mutations. The primary endpoint was PCR-corrected parasitological cure on day 28, as per WHO protocol.. 228 participants were enrolled and 224 (98·2%) reached the study endpoint. PCR-corrected efficacies were 97·0% (95% CI 88-100) in Masaka, 93·8% (85-98) in Rukara, and 97·2% (91-100) in Bugarama. Pfkelch13 R561H mutations were present in 28 (13%) of 218 pre-treatment samples and P574L mutations were present in two (1%) pre-treatment samples. 217 (90%) of the 240 Pfmdr1 haplotypes observed in the pretreatment samples, had either the NFD (N86Y, Y184F, D1246Y) or NYD haplotype. Eight (16%) of 51 participants in Masaka and 12 (15%) of 82 participants in Rukara were microscopically positive 3 days after treatment initiation, which was associated with pre-treatment presence of Pfkelch13 R561H in Masaka (p=0·0005). Genetic analysis of Pfkelch13 R561H mutations suggest their common ancestry and local origin in Rwanda.. We confirm evidence of emerging artemisinin partial resistance in Rwanda. Although artemether-lumefantrine remains efficacious, vigilance for decreasing efficacy, further characterisation of artemisinin partial resistance, and evaluation of additional antimalarials in Rwanda should be considered.. The US President's Malaria Initiative.. For the French translation of the abstract see Supplementary Materials section.

Topics: Animals; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Child, Preschool; Drug Resistance; Female; Genotype; Humans; Infant; Malaria, Falciparum; Male; Mutation, Missense; Parasitic Sensitivity Tests; Plasmodium falciparum; Polymorphism, Genetic; Protozoan Proteins; Rwanda

Artemether-lumefantrine is a highly effective artemisinin-based combination therapy that was adopted in Mali as first-line treatment for uncomplicated. A 28-day follow-up efficacy trial of artemether-lumefantrine was conducted in patients aged 6 months and older suffering from uncomplicated falciparum malaria in four different Malian areas during the 2009 malaria transmission season. The polymorphic genetic markers MSP2, MSP1, and Ca1 were used to distinguish between recrudescence and reinfection. Reinfection and recrudescence were then grouped as recurrent infections and analyzed together by PCR-restriction fragment length polymorphism (RFLP) to identify candidate markers for artemether-lumefantrine tolerance in the. Clinical outcomes in 326 patients (96.7%) were analyzed and the 28-day uncorrected adequate clinical and parasitological response (ACPR) rate was 73.9%. The total PCR-corrected 28-day ACPR was 97.2%. The. Parasite populations exposed to artemether-lumefantrine in this study were selected toward chloroquine-sensitivity and showed a promising trend that may warrant future targeted reintroduction of chloroquine or/and amodiaquine.

Topics: Alleles; Artemether, Lumefantrine Drug Combination; Artemisinins; Child; Child, Preschool; Chloroquine; Drug Resistance; Female; Humans; Malaria, Falciparum; Male; Membrane Transport Proteins; Multidrug Resistance-Associated Proteins; Plasmodium falciparum; Protozoan Proteins

The choice of malaria treatment for HIV-infected pregnant women receiving efavirenz-based antiretroviral therapy must consider the potential impact of drug interactions on antimalarial exposure and clinical response. The aim of this study was to investigate the effects of efavirenz on artemether-lumefantrine (AL) because no studies have isolated the impact of efavirenz for HIV-infected pregnant women.. A prospective clinical pharmacokinetic (PK) study compared HIV-infected, efavirenz-treated pregnant women with HIV-uninfected pregnant women in Tororo, Uganda. All women received the standard 6-dose AL treatment regimen for Plasmodium falciparum malaria with intensive PK samples collected over 21 days and 42-days of clinical follow-up. PK exposure parameters were calculated for artemether, its active metabolite dihydroartemisinin (DHA), and lumefantrine to determine the impact of efavirenz.. Nine HIV-infected and 30 HIV-uninfected pregnant women completed intensive PK evaluations. Relative to controls, concomitant efavirenz therapy lowered the 8-hour artemether concentration by 76% (P = 0.013), DHA peak concentration by 46% (P = 0.033), and day 7 and 14 lumefantrine concentration by 61% and 81% (P = 0.046 and 0.023), respectively. In addition, there were nonsignificant reductions in DHA area under the concentration-time curve0-8hr (35%, P = 0.057) and lumefantrine area under the concentration-time curve0-∞ (34%, P = 0.063) with efavirenz therapy.. Pregnant HIV-infected women receiving efavirenz-based antiretroviral therapy during malaria treatment with AL showed reduced exposure to both the artemisinin and lumefantrine. These data suggest that malaria and HIV coinfected pregnant women may require adjustments in AL dosage or treatment duration to achieve exposure comparable with HIV-uninfected pregnant women.

Topics: Adolescent; Adult; Alkynes; Anti-HIV Agents; Anti-Retroviral Agents; Antimalarials; Artemether; Artemether, Lumefantrine Drug Combination; Artemisinins; Benzoxazines; Cyclopropanes; Drug Combinations; Drug Interactions; Female; HIV Infections; Humans; Lumefantrine; Malaria; Malaria, Falciparum; Pregnancy; Prospective Studies; Uganda; Young Adult

Efficient testing to identify poor quality artemisinin-based combination therapy (ACT) is important to optimize efforts to control and eliminate malaria. Healthcare professionals interact with both ACT and malaria patients they treat and hence could observe, first-hand, suspect poor quality artemisinin-based combinations linked to poor malaria treatment outcomes and the factors associated with inappropriate use or treatment failure.. A cross-sectional study of 685 HCP perspectives about the efficacy of ACT between June and July 2018 at selected health facilities in Uganda. Medicine samples were obtained from the seven regions of Uganda and tested for quality using the Germany Pharma Health Fund™ minilabs.. The average age of the 685 respondents was 30 (SD = 7.4) years. There was an almost equal distribution between male and female respondents (51:49), respectively. Seventy percent (n = 480) were diploma holders and the nurses contributed to half (49%, n = 334) of the study population. Sixty-one percent of the HCPs reported having ever encountered ACT failures while treating uncomplicated malaria. Nineteen percent of HCPs thought that dihydroartemisinin/piperaquine gave the most satisfactory patient treatment outcomes, while 80% HCPs thought that artemether/lumefantrine gave the least satisfactory patient treatment outcomes, possibly due to dosing schedule and pill burden. Healthcare professionals from the Central region (OR = 3.0, CI 0.3-1.0; P = 0.0001), Eastern region (OR = 5.4, CI 2.9-9.8; P = 0.0001) and Northern region (OR = 5.3, CI 2.9-9.9; P = 0.0001) had a higher chance of encountering ACT failure in 4 weeks prior to the survey as compared to those from the western region. Healthcare professionals from private health facilities also had higher chances of encountering ACT failures in past 4 weeks as compared to those from public health facilities (OR = 2.7, CI 1.7-3.9; P = 0.0001). All 192 samples passed the quality screening tests. The random sample of 10% of all samples randomly obtained by the laboratory staff also passed the chemical content analysis and dissolution tests.. ACT medicines are widely available over-the-counter to the public and it is very difficult to report and monitor a decrease in efficacy or treatment failure. The perspectives of HCPs on treatment failure or lack of efficacy may potentially guide optimization efforts of sampling methodologies for the quality survey of ACT medicines.

Topics: Adult; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Cross-Sectional Studies; Drug Resistance; Drug Therapy, Combination; Female; Health Personnel; Humans; Logistic Models; Malaria; Male; Patient Compliance; Plasmodium falciparum; Product Surveillance, Postmarketing; Quinolines; Sesquiterpenes; Surveys and Questionnaires; Tablets; Treatment Failure; Uganda

Nigeria bears 25% of global malaria burden despite concerted efforts towards its control and elimination. The emergence of drug resistance to first line drugs, artemisinin combination therapies (ACTs), indicates an urgent need for continuous molecular surveillance of drug resistance especially in high burden countries where drug interventions are heavily relied on. This study describes mutations in Plasmodium falciparum genes associated with drug resistance in malaria; Pfk13, Pfmdr1, PfATPase6 and Pfcrt in isolates obtained from 83 symptomatic malaria patients collected in August 2014, aged 1-61 years old from South-west Nigeria.. Two Pfmdr1, N86 and Y184 variants were present at a prevalence of 56% and 13.25% of isolates respectively. There was one synonymous (S679S) and two non-synonymous (M699V, S769M) mutations in the PATPase6 gene, while Pfcrt genotype (CVIET), had a prevalence of 45%. The Pfk13 C580Y mutant allele was suspected by allelic discrimination in two samples with mixed genotypes although this could not be validated with independent isolation or additional methods. Our findings call for robust molecular surveillance of antimalarial drug resistance markers in west Africa especially with increased use of antimalarial drugs as prophylaxis for Covid-19.

Topics: Adolescent; Adult; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Calcium-Transporting ATPases; Child; Child, Preschool; Coronavirus Infections; COVID-19; Drug Resistance; Female; Gene Expression; Genotype; Humans; Infant; Malaria, Falciparum; Membrane Transport Proteins; Middle Aged; Molecular Epidemiology; Multidrug Resistance-Associated Proteins; Mutation; Nigeria; Pandemics; Plasmodium falciparum; Pneumonia, Viral; Protozoan Proteins

The potential spread of antimalarial drug resistance to Africa, in particular for artemisinins and key partner drugs, is a major concern. We surveyed

Topics: Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Aspartic Acid Endopeptidases; Child; Chloroquine; Drug Resistance; Folic Acid Antagonists; Humans; Lumefantrine; Malaria, Falciparum; Membrane Transport Proteins; Multidrug Resistance-Associated Proteins; Plasmodium falciparum; Polymorphism, Single Nucleotide; Protozoan Proteins; Quinolines; Uganda

Several antimalarial drugs are known to prolong ventricular repolarization as evidenced by QT/QTc interval prolongation. This can lead to Torsades de Pointes, a potentially lethal ventricular arrhythmia. Whether this is the case with artemisinin-based combination therapies (ACTs) remains uncertain. Assessment of the extent of QTc prolongation with antimalarials is hampered by important variations of heart rate during malaria crises and previous studies have reported highly variable values of QTc prolongations with ACTs. We assessed QTc prolongation with four ACTs, using high quality ECG recording and measurement techniques, during the first episode of malaria in 2,091 African patients enrolled in the WANECAM study which also monitored clinical safety. Using an original and robust method of QTc assessment, independent from heart rate changes and from the method of QT correction, we were able to accurately assess the extent of mean maximum QTc prolongation with the four ACTs tested. There was no evidence of proarrhythmia with any treatment during the study although dihydroartemisinin-piperaquine, artesunate-amodiaquine and artemether-lumefantrine significantly prolonged QTc. The extent of prolongation of ventricular repolarization can be accurately assessed in studies where heart rate changes impede QTc assessment.

Topics: Adolescent; Amodiaquine; Antimalarials; Arrhythmias, Cardiac; Artemether; Artemether, Lumefantrine Drug Combination; Artemisinins; Child; Child, Preschool; Drug Combinations; Ethanolamines; Female; Fluorenes; Heart Rate; Humans; Long QT Syndrome; Malaria; Malaria, Falciparum; Male; Quinolines; Young Adult

Artemisinin-based combination therapy is the first-line anti-malarial treatment for uncomplicated Plasmodium falciparum infection in Angola. To date, the prevalence of polymorphisms in the pfk13 gene, associated with artemisinin resistance, and pfmdr1, associated with lumefantrine resistance, have not been systematically studied in Angola.. DNA was isolated from pretreatment and late treatment failure dried blood spots collected during the 2015 round of therapeutic efficacy studies in Benguela, Lunda Sul, and Zaire Provinces in Angola. The pfk13 propeller domain and pfmdr1 gene were sequenced and analysed for polymorphisms. Pfmdr1 copy number variation was assessed using a real-time PCR method. The association between pfmdr1 and pfk13 mutations and treatment failure was investigated.. The majority of pretreatment (99%, 466/469) and all late treatment failure (100%, 50/50) samples were wild type for pfk13. Three of the pretreatment samples (1%) carried the A578S mutation commonly observed in Africa and not associated with artemisinin resistance. All 543 pretreatment and day of late treatment failure samples successfully analysed for pfmdr1 copy number variation carried one copy of pfmdr1. The NYD haplotype was the predominant pfmdr1 haplotype, present in 63% (308/491) of pretreatment samples, followed by NFD, which was present in 32% (157/491) of pretreatment samples. The pfmdr1 N86 allele was overrepresented in day of late treatment failure samples from participants receiving artemether-lumefantrine (p value 0.03).. The pretreatment parasites in patients participating in therapeutic efficacy studies in 2015 in Angola's three sentinel sites showed genetic evidence of susceptibility to artemisinins, consistent with clinical outcome data showing greater than 99% day 3 clearance rates. The lack of increased pfmdr1 copy number is consistent with previous reports from sub-Saharan Africa. Although pfmdr1 NYD and NFD haplotypes were overrepresented in artemether-lumefantrine late treatment failure samples, their role as markers of resistance was unclear given that these haplotypes were also present in the majority of successfully treated patients in the artemether-lumefantrine treatment arms.

Topics: Angola; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Biomarkers; Drug Resistance; Humans; Lumefantrine; Malaria, Falciparum; Multidrug Resistance-Associated Proteins; Plasmodium falciparum; Polymorphism, Genetic; Protozoan Proteins

Data on prevalence of antimalarial molecular resistance markers in pregnant women in Ghana is scarce. Prevalence of single nucleotide polymorphisms/haplotypes in the

Topics: Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Cross-Sectional Studies; Drug Combinations; Drug Resistance; Female; Genetic Markers; Ghana; Haplotypes; Humans; Infant, Newborn; Malaria, Falciparum; Membrane Transport Proteins; Multidrug Resistance-Associated Proteins; Mutation; Plasmodium falciparum; Polymorphism, Single Nucleotide; Pregnancy; Protozoan Proteins; Pyrimethamine; Sulfadoxine; Tetrahydrofolate Dehydrogenase

Dried leaf Artemisia annua (DLA) has shown efficacy against Plasmodium sp. in rodent studies and in small clinical trials. Rodent malaria also showed resiliency against the evolution of artemisinin drug resistance.. This is a case report of a last resort treatment of patients with severe malaria who were responding neither to artemisinin combination therapy (ACT) nor i.v. artesunate.. Of many patients treated with ACTs and i.v. artesunate during the 6 mon study period, 18 did not respond and were subsequently treated with DLA Artemisia annua.. Patients were given a dose of 0.5g DLA per os, twice daily for 5d. Total adult delivered dose of artemisinin was 55mg. Dose was reduced for body weight under 30kg. Clinical symptoms, e.g. fever, coma etc., and parasite levels in thick blood smears were tracked. Patients were declared cured and released from hospital when parasites were microscopically undetectable and clinical symptoms fully subsided.. All patients were previously treated with Coartem® provided through Santé Rurale (SANRU) and following the regimen prescribed by WHO. Of 18 ACT-resistant severe malaria cases compassionately treated with DLA, all fully recovered. Of the 18, this report details two pediatric cases.. Successful treatment of all 18 ACT-resistant cases suggests that DLA should be rapidly incorporated into the antimalarial regimen for Africa and possibly wherever else ACT resistance has emerged.

Topics: Administration, Intravenous; Adolescent; Adult; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisia annua; Artemisinins; Artesunate; Child; Child, Preschool; Drug Combinations; Drug Resistance, Microbial; Ethanolamines; Female; Fluorenes; Humans; Infant; Malaria; Male; Middle Aged; Plant Leaves; Tablets; Treatment Outcome; Young Adult

Artemisinin-based combination therapy has been first-line treatment for falciparum malaria in Myanmar since 2005. The wide extent of artemisinin resistance in the Greater Mekong sub-region and the presence of mefloquine resistance at the Myanmar-Thailand border raise concerns over resistance patterns in Myanmar. The availability of molecular markers for resistance to both drugs enables assessment even in remote malaria-endemic areas.. A total of 250 dried blood spot samples collected from patients with Plasmodium falciparum malarial infection in five malaria-endemic areas across Myanmar were analysed for kelch 13 sequence (k13) and pfmdr1 copy number variation. K13 mutations in the region corresponding to amino acids 210-726 (including the propeller region of the protein) were detected by nested PCR amplification and sequencing, and pfmdr1 copy number variation by real-time PCR. In two sites, a sub-set of patients were prospectively followed up for assessment of day-3 parasite clearance rates after a standard course of artemether-lumefantrine.. K13 mutations and pfmdr1 amplification were successfully analysed in 206 and 218 samples, respectively. Sixty-nine isolates (33.5 %) had mutations within the k13 propeller region with 53 of these (76.8 %) having mutations already known to be associated with artemisinin resistance. F446I (32 isolates) and P574L (15 isolates) were the most common examples. K13 mutation was less common in sites in western border regions (29 of 155 isolates) compared to samples from the east and north (40 of 51 isolates; p < 0.0001). The overall proportion of parasites with multiple pfmdr1 copies (greater than 1.5) was 5.5 %. Seven samples showed both k13 mutation and multiple copies of pfmdr1. Only one of 36 patients followed up after artemether-lumefantrine treatment still had parasites at day 3; molecular analysis indicated wild-type k13 and single copy pfmdr1.. The proportion of P. falciparum isolates with mutations in the propeller region of k13 indicates that artemisinin resistance extends across much of Myanmar. There is a low prevalence of parasites with multiple pfmdr1 copies across the country. The efficacy of artemisinin-based combination therapy containing mefloquine and lumefantrine is, therefore, expected to be high, although regular monitoring of efficacy will be important.

Topics: Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; DNA Copy Number Variations; DNA, Protozoan; Drug Combinations; Ethanolamines; Fluorenes; Humans; Malaria, Falciparum; Multidrug Resistance-Associated Proteins; Mutation; Myanmar; Plasmodium falciparum; Prospective Studies

In Benin, artemisinin-based combination therapy (ACT) has been recommended as the first-line treatment for uncomplicated Plasmodium falciparum malaria since 2004. The emergence in Southeast Asia of parasites that are resistant to artemisinins poses a serious threat to global control of this disease. The presence of artemisinin resistance genotypes in parasite populations in Benin is currently unknown. The present study investigated the prevalence of relevant K13-propeller gene polymorphisms in parasite isolates from the north-western region of Benin.. Plasmodium falciparum isolates were collected from children with a confirmed diagnosis of malaria aged 6 months to 5 years in two towns, Cobly and Djougou, in the north-western part of Benin. The study was conducted during the rainy season from July to November 2014 in local health facilities. The K13-propeller gene was amplified in parasite isolates using nested PCR and subsequently sequenced.. A total of 108 children were recruited into the study. The efficiency of amplification reactions was 72% (78/108). The propeller domain of the K13 gene was successfully sequenced in 78 P. falciparum isolates; all of them were wild type with no polymorphisms detectable.. The absence of mutations in the K13 gene indicates that P. falciparum parasite populations in the study area are still fully susceptible to artemisinins.

Topics: Anti-Infective Agents; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Benin; Child, Preschool; DNA, Protozoan; Drug Combinations; Drug Resistance; Ethanolamines; Fluorenes; Humans; Infant; Malaria, Falciparum; Plasmodium falciparum; Polymorphism, Genetic; Sequence Alignment

The mechanisms of drug resistance development in the Plasmodium falciparum parasite to lumefantrine (LUM), commonly used in combination with artemisinin, are still unclear. We assessed the polymorphisms of Pfmspdbl2 for associations with LUM activity in a Kenyan population. MSPDBL2 codon 591S was associated with reduced susceptibility to LUM (P = 0.04). The high frequency of Pfmspdbl2 codon 591S in Kenya may be driven by the widespread use of lumefantrine in artemisinin combination therapy (Coartem).

Topics: Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Codon; Drug Combinations; Drug Resistance; Ethanolamines; Fluorenes; Humans; Kenya; Lumefantrine; Malaria, Falciparum; Plasmodium falciparum; Polymorphism, Genetic; Protozoan Proteins

There is considerable concern that malaria parasites are starting to evolve resistance to the current generation of antimalarial drugs, the artemisinin-based combination therapies (ACTs). We use pharmacological modeling to investigate changes in ACT effectiveness likely to occur if current regimens are extended from 3 to 5 days or, alternatively, given twice daily over 3 days. We show that the pharmacology of artemisinins allows both regimen changes to substantially increase the artemisinin killing rate. Malaria patients rarely contain more than 10(12) parasites, while the standard dosing regimens allow approximately 1 in 10(10) parasites to survive artemisinin treatment. Parasite survival falls dramatically, to around 1 in 10(17) parasites if the dose is extended or split; theoretically, this increase in drug killing appears to be more than sufficient to restore failing ACT efficacy. One of the most widely used dosing regimens, artemether-lumefantrine, already successfully employs a twice-daily dosing regimen, and we argue that twice-daily dosing should be incorporated into all ACT regimen design considerations as a simple and effective way of ensuring the continued long-term effectiveness of ACTs.

Topics: Adult; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Child; Dose-Response Relationship, Drug; Drug Administration Schedule; Drug Combinations; Drug Dosage Calculations; Ethanolamines; Female; Fluorenes; Humans; Malaria, Falciparum; Male; Models, Statistical; Parasitic Sensitivity Tests; Plasmodium falciparum; Pregnancy; Treatment Outcome

Artemisinin combination therapies (ACTs) are used worldwide as first-line treatment against confirmed or suspected Plasmodium falciparum malaria. Despite the success of ACTs at reducing the global burden of malaria, emerging resistance to artemisinin threatens these gains. Countering onset of resistance might need deliberate tactics aimed at slowing the reduction in ACT effectiveness. We assessed optimum use of ACTs at the population level, specifically focusing on a strategy of multiple first-line therapies (MFT), and comparing it with strategies of cycling or sequential use of single first-line ACTs.. With an individual-based microsimulation of regional malaria transmission, we looked at how to apply a therapy as widely as possible without accelerating reduction of efficacy by drug resistance. We compared simultaneous distribution of artemether-lumefantrine, artesunate-amodiaquine, and dihydroartemisinin-piperaquine (ie, MFT) against strategies in which these ACTs would be cycled or used sequentially, either on a fixed schedule or when population-level efficacy reaches the WHO threshold of 10% treatment failure. The main assessment criterion was total number of treatment failures per 100 people per year. Additionally, we analysed the benefits of including a single non-ACT therapy in an MFT strategy, and did sensitivity analyses in which we varied transmission setting, treatment coverage, partner-drug half-life, fitness cost of drug resistance, and the relation between drug concentration and resistance evolution.. Use of MFT was predicted to reduce the long-term number of treatment failures compared with strategies in which a single first-line ACT is recommended. This result was robust to various epidemiological, pharmacological, and evolutionary features of malaria transmission. Inclusion of a single non-ACT therapy in an MFT strategy would have substantial benefits in reduction of pressure on artemisinin resistance evolution, delaying its emergence and slowing its spread.. Adjusting national antimalarial treatment guidelines to encourage simultaneous use of MFT is likely to extend the useful therapeutic life of available antimalarial drugs, resulting in long-term beneficial outcomes for patients.. Wellcome Trust, UK Medical Research Council, Li Ka Shing Foundation.

Topics: Amodiaquine; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Drug Administration Schedule; Drug Combinations; Drug Resistance; Ethanolamines; Fluorenes; Humans; Malaria, Falciparum; Models, Biological; Plasmodium falciparum; Quinolines; Treatment Failure

Artemisinin-based combination therapy (ACT) has been adopted as the most effective treatment against malaria in many endemic countries like Kenya while quinine has remained the second line. The objective of the current study was to assess access to Kenya's policy recommended anti-malarials, ACT and quinine in the public, private and not-for-profit drug outlets in western Kenya.. A cross-sectional survey using purposive sampling of 288 outlets (126 public, 96 private, 66 not-for-profit) was conducted in western Kenya in two regions with varying Plasmodium falciparum endemicities. Information on access (availability, price, affordability) on ACT and quinine was collected using the WHO and Healthcare Associated Infection (HAI) standardized methodologies for availability, prices and affordability of drugs. From a Ministry of Health database, the following were included in the analyses: one (1) main public hospital, followed by random selection of five hospitals under this main facility. Eight other public outlets under each of the hospitals were selected, to a total of 96. Matching number of private outlets (n = 96), all (66) not-for-profit outlets and additional 30 public health facilities were sampled to get the required sample size of 288.. More public 111 (88.1%) and not-for-profit 27 (40.9%) outlets stocked subsidized ACT (artemether-lumefantrine, AL). Other artemisinin-based combinations were widely available for both children 93 (96.9%) and adults 82 (85.0%) in private outlets. Frequent stock-outs were in public in 106 (84%), reporting three times or more stock-outs in three months. Subsidized ACT (AL) was sold at median price of USD 0.94 and 0.75 in private and not-for-profit outlets respectively. The costs was higher than recommended price of USD 0.5 and requiring up to 0.20-0.25 days of disposable income for households in lowest economic status.. There is low availability of subsidized ACT (AL) and higher frequency of stock-outs in government facilities, while private sector sells AL at higher prices, thus making it less affordable to many households. These factors determine the adherence to the dosing schedules during the treatment course and thus the evaluation of the subsidy policy, its implementation and role in malaria burden in this region is compulsory.

Topics: Adult; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Child; Cross-Sectional Studies; Drug Combinations; Ethanolamines; Fluorenes; Health Services Accessibility; Humans; Kenya; Malaria; Quinine

The pharmacogenetics of antimalarial agents are poorly known, although the application of pharmacogenetics might be critical in optimizing treatment. This population pharmacokinetic-pharmacogenetic study aimed at assessing the effects of single nucleotide polymorphisms (SNPs) in cytochrome P450 isoenzyme genes (CYP, namely, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP3A4, and CYP3A5) and the N-acetyltransferase 2 gene (NAT2) on the pharmacokinetics of artemisinin-based combination therapies in 150 Tanzanian patients treated with artemether-lumefantrine, 64 Cambodian patients treated with artesunate-mefloquine, and 61 Cambodian patients treated with dihydroartemisinin-piperaquine. The frequency of SNPs varied with the enzyme and the population. Higher frequencies of mutant alleles were found in Cambodians than Tanzanians for CYP2C9*3, CYP2D6*10 (100C → T), CYP3A5*3, NAT2*6, and NAT2*7. In contrast, higher frequencies of mutant alleles were found in Tanzanians for CYP2D6*17 (1023C → T and 2850C → T), CYP3A4*1B, NAT2*5, and NAT2*14. For 8 SNPs, no significant differences in frequencies were observed. In the genetic-based population pharmacokinetic analyses, none of the SNPs improved model fit. This suggests that pharmacogenetic data need not be included in appropriate first-line treatments with the current artemisinin derivatives and quinolines for uncomplicated malaria in specific populations. However, it cannot be ruled out that our results represent isolated findings, and therefore more studies in different populations, ideally with the same artemisinin-based combination therapies, are needed to evaluate the influence of pharmacogenetic factors on the clearance of antimalarials.

Topics: Alleles; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Artesunate; Arylamine N-Acetyltransferase; Base Sequence; Cambodia; Cytochrome P-450 Enzyme System; Drug Combinations; Ethanolamines; Fluorenes; Gene Frequency; Humans; Isoenzymes; Malaria; Mefloquine; Pharmacogenetics; Polymorphism, Single Nucleotide; Quinolines; Sequence Analysis, DNA; Tanzania

Priority setting for artemisinin-based antimalarial drugs has become an integral part of malaria treatment policy change in malaria-endemic countries. Although these drugs are more efficacious, they are also more costly than the failing drugs. When Tanzania changed its National Malaria Treatment Policy in 2006, priority setting was an inevitable challenge. Artemether-lumefantrine was prioritised as the first-line drug for the management of uncomplicated malaria to be available at a subsidized price at public and faith-based healthcare facilities.. This paper describes the priority-setting process, which involved the selection of a new first-line antimalarial drug in the implementation of artemisinin-based combination therapy policy. These descriptions were further evaluated against the four conditions of the accountability for reasonableness framework. According to this framework, fair decisions must satisfy a set of publicity, relevance, appeals, and revision and enforcement conditions.In-depth interviews were held with key informants using pretested interview guides, supplemented with a review of the treatment guideline. Purposeful sampling was used in order to explore the perceptions of people with different backgrounds and perspectives. The analysis followed an editing organising style.. Publicity: The selection decision of artemether-lumefantrine but not the rationale behind it was publicised through radio, television, and newspaper channels in the national language, Swahili.. The decision was grounded on evidences of clinical efficacy, safety, affordability, and formulation profile. Stakeholders were not adequately involved. There was neither an appeals mechanism to challenge the decision nor enforcement mechanisms to guarantee fairness of the decision outcomes.. The priority-setting decision to use artemether-lumefantrine as the first-line antimalarial drug failed to satisfy the four conditions of the accountability for reasonableness framework. In our understanding, this is the first study to evaluate priority-setting decisions for new drugs in Tanzania against the accountability for reasonableness framework. In addition to the demand for enhanced stakeholder involvement, publicity, and transparency, the study also calls for the institution of formal appeals, revision, and regulatory mechanisms in the future change of malaria treatment policies.

Topics: Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Cost-Benefit Analysis; Data Collection; Drug Combinations; Drug Industry; Drug Resistance, Multiple; Ethanolamines; Fluorenes; Health Priorities; Humans; Malaria, Falciparum; Sample Size; Social Responsibility; Tanzania; Treatment Outcome

WHO estimates that only 3% of fever patients use recommended artemisinin-based combination therapies (ACTs), partly reflecting their high prices in the retail sector from where many patients seek treatment. To overcome this challenge, a global ACT subsidy has been proposed. We tested this proposal through a pilot program in rural Tanzania.. Three districts were assigned to serve either as a control or to receive the subsidy plus a package of supporting interventions. From October 2007, ACTs were sold at a 90% subsidy through the normal private supply chain to intervention district drug shops. Data were collected at baseline and during intervention using interviews with drug shop customers, retail audits, mystery shoppers, and audits of public and NGO facilities. The proportion of consumers in the intervention districts purchasing ACTs rose from 1% at baseline to 44.2% one year later (p<0.001), and was significantly higher among consumers purchasing for children under 5 than for adults (p = 0.005). No change in ACT usage was observed in the control district. Consumers paid a mean price of $0.58 for ACTs, which did not differ significantly from the price paid for sulphadoxine-pyrimethamine, the most common alternative. Drug shops in population centers were significantly more likely to stock ACTs than those in more remote areas (p<0.001).. A subsidy introduced at the top of the private sector supply chain can significantly increase usage of ACTs and reduce their retail price to the level of common monotherapies. Additional interventions may be needed to ensure access to ACTs in remote areas and for poorer individuals who appear to seek treatment at drug shops less frequently.. Controlled-Trials.com ISRCTN39125414.

Topics: Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Commerce; Drug Combinations; Drug Costs; Ethanolamines; Financing, Government; Fluorenes; Health Services Accessibility; Humans; Malaria; Pilot Projects; Private Sector; Pyrimethamine; Rural Health; Rural Population; Sulfadoxine; Tanzania

An assessment of the accuracy of two malaria rapid diagnostic tests (RDT) for the detection of Plasmodium falciparum histidine-rich protein 2 (PfHRP2) or Pf lactate dehydrogenase (PfLDH) was undertaken in children aged between six and 59 months included in an anti-malarial efficacy study in Benin.. In Allada (Benin), 205 children aged 6-59 months with falciparum malaria received either artesunate-amodiaquine (ASAQ), artemether-lumefantrine (AL), or sulphadoxine-pyrimethamine (SP). Children included in the study were simultaneously followed by both RDT and high-quality microscopy for up to 42 days.. At the time of inclusion, PfHRP2-based tests were positive in 203 children (99%) and PfLDH-based tests were positive in 204 (99.5%). During follow-up, independent of the treatment received, only 17.3% (28/162) of children effectively cured were negative with the PfHRP2 RDT at day 3, with a gradual increase in specificity until day 42. The specificity of antigen detection with the PfLDH test was 87% (141/162) on day 3, and between 92% and 100% on days 7 to 42. A statistical difference was observed between the persistence of PfHRP2 and PfLDH antigenaemia during follow-up in children treated with artemisinin-based combination therapy (ACT) but not with SP.. Although both RDTs are as sensitive as microscopy in detecting true malaria cases, the PfHRP2 RDT had very low specificity during follow-up until day 28. On the other hand, the PfLDH test could be used to detect failures and, therefore, to assess anti-malarial efficacy.

Topics: Amodiaquine; Antigens, Protozoan; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Benin; Blood; Child, Preschool; Drug Combinations; Drug Monitoring; Drug Therapy, Combination; Ethanolamines; Fluorenes; Follow-Up Studies; Humans; Infant; L-Lactate Dehydrogenase; Malaria, Falciparum; Microscopy; Molecular Diagnostic Techniques; Protozoan Proteins; Pyrimethamine; Sensitivity and Specificity; Sulfadoxine; Treatment Outcome

Malaria continues to be one of the major public health problems in Africa, Asia and Latin America. Artemisinin derivatives (ARTs; artesunate, artemether, and dihydroartemisinin) derived from the herb, Artemisia annua, are the most effective antimalarial drugs available providing rapid cures. The World Health Organisation (WHO) has recommended that all antimalarials must be combined with an artemisinin component (artemisinin-based combination therapy; ACT) for use as first line treatment against malaria. This class of drugs is now first-line policy in most malaria-endemic countries. Reports of ad hoc surveys from South East Asia show that up to 50% of the artesunate currently sold is counterfeit. Drug quality is rarely assessed in resource poor countries in part due to lack of dedicated laboratory facilities which are expensive to build, equip and maintain. With a view to address this unmet need we developed two novel colour reaction assays that can be used in the field to check the quality of ARTs.. Our assays utilise thin layer chromatography silica gel sheets and 2, 4 dinitrophenylhydrazine or 4-Benzoylamino-2, 5-dimethoxybenzenediazonium chloride hemi (zinc chloride) salt as the reagents showing a pink or blue product respectively only in the presence ARTs. We are able to detect as low as 10% of ARTs in ACTs (WINTHROP--artesunate/amodiaquine, Coartem--artemether/lumefantrine and Duocortexcin--dihydroartemisinin/piperaquine). The assays have been validated extensively by testing eighty readily accessible and widely used drugs in malaria endemic countries. None of the other antimalarial drugs or a range of commonly used excipients, antiretroviral drugs or other frequently used drugs from the WHO essential drugs list such as analgesics or antibiotics are detected with our assays.. Our two independent assays requiring no specialist training are specific, simple to use, rapid, robust, reproducible, inexpensive and, have successfully resulted in detecting two counterfeit drugs within a small scale screening survey of over 100 declared artemisinin-containing drugs collected from various Asian and African countries. These promising results indicate that the assays will provide a useful first test to assure the quality of the ACTs formulations in resource poor malaria endemic areas when there is an absence of dedicated medicines quality laboratory facilities.

Topics: Animals; Antimalarials; Artemether, Lumefantrine Drug Combination; Artemisinins; Chemistry, Pharmaceutical; Chromatography, High Pressure Liquid; Chromatography, Thin Layer; Drug Combinations; Drug Evaluation, Preclinical; Ethanolamines; Fluorenes; Malaria; Pharmaceutical Preparations; Reference Standards; Sensitivity and Specificity; Silicon Dioxide; Tablets

Highland areas where malaria transmission is unstable are targets for malaria elimination because transmission decreases to low levels during the dry season. In highland areas of Kipsamoite and Kapsisiywa, Kenya (population approximately 7,400 persons), annual household indoor residual spraying with a synthetic pyrethroid was performed starting in 2005, and artemether/lumefantrine was implemented as first-line malaria treatment in October 2006. During April 2007-March 2008, no microscopy-confirmed cases of malaria occurred at the sites. In 4 assessments of asymptomatic persons during May 2007-April 2008, a total of <0.3% of persons were positive for asexual Plasmodium falciparum by microscopy or PCR at any time, and none were positive by PCR at the last 2 sample collections. Our findings show that in such areas, interruption and eventual elimination of malaria transmission may be achievable with widespread annual indoor residual spraying of households and artemisinin combination therapy.

Topics: Animals; Artemether, Lumefantrine Drug Combination; Artemisinins; Drug Combinations; Ethanolamines; Fluorenes; Health Policy; Humans; Insecticides; Kenya; Malaria; Mosquito Control; Parasitemia; Polymerase Chain Reaction; Rain; Temperature; Time Factors