Artemether-lumefantrine Research Articles

Therapeutic response to four artemisinin-based combination therapies in Angola, 2021.

Monitoring antimalarial efficacy is important to detect the emergence of parasite drug resistance. Angola conducts in vivo therapeutic efficacy studies (TESs) every 2 years in its fixed sentinel sites in Benguela, Lunda Sul, and Zaire provinces. Children with uncomplicated Plasmodium falciparum malaria were treated with artemether-lumefantrine (AL), artesunate-amodiaquine (ASAQ), dihydroartemisinin-piperaquine (DP), or artesunate-pyronaridine (ASPY) and followed for 28 (AL and ASAQ) or 42 days (DP and ASPY) to assess clinical and parasitological response to treatment. Two drugs were sequentially assessed in each site in February-July 2021. The primary indicator was the Kaplan-Meier estimate of the PCR-corrected efficacy at the end of the follow-up period. A total of 622 patients were enrolled in the study and 590 (95%) participants reached a study endpoint. By day 3, ≥98% of participants were slide-negative in all study sites and arms. After PCR correction, day 28 AL efficacy was 88.0% (95% CI: 82%-95%) in Zaire and 94.7% (95% CI: 90%-99%) in Lunda Sul. For ASAQ, day 28 efficacy was 92.0% (95% CI: 87%-98%) in Zaire and 100% in Lunda Sul. Corrected day 42 efficacy was 99.6% (95% CI: 99%-100%) for ASPY and 98.3% (95% CI: 96%-100%) for DP in Benguela. High day 3 clearance rates suggest no clinical evidence of artemisinin resistance. This was the fourth of five rounds of TES in Angola showing a corrected AL efficacy <90% in a site. For Zaire, AL has had an efficacy <90% in 2013, 2015, and 2021. ASAQ, DP, and ASPY are appropriate choices as artemisinin-based combination therapies in Angola.

Safety and efficacy of pyronaridine–artesunate paediatric granules in the treatment of uncomplicated malaria in children: insights from randomized clinical trials and a real-world study

BackgroundChildren are particularly at risk of malaria. This analysis consolidates the clinical data for pyronaridine–artesunate (PA) paediatric granules in children from three randomized clinical trials and a real-world study (CANTAM).MethodsAn integrated safety analysis of individual patient data from three randomized clinical trials included patients with microscopically-confirmed Plasmodium falciparum, body weight ≥ 5 kg to < 20 kg, who received at least one dose of study drug (paediatric safety population). PA was administered once daily for 3 days; two trials included the comparator artemether–lumefantrine (AL). PCR-adjusted day 28 adequate clinical and parasitological response (ACPR) was evaluated. Real-world PA granules safety and effectiveness was also considered.ResultsIn the integrated safety analysis, 63.9% (95% CI 60.2, 67.4; 426/667) of patients had adverse events following PA and 62.0% (95% CI 56.9, 66.9; 222/358) with AL. Vomiting was more common with PA (7.8% [95% CI 6.0, 10.1; 52/667]) than AL (3.4% [95% CI 1.9, 5.8; 12/358]), relative risk 2.3 (95% CI 1.3, 4.3; P = 0.004), occurring mainly following the first PA dose (6.7%, 45/667), without affecting re-dosing or adherence. Prolonged QT interval occurred less frequently with PA (3.1% [95% CI 2.1, 4.8; 21/667]) than AL (8.1% [95% CI 5.7, 11.4; 29/358]), relative risk 0.39 (95% CI 0.22, 0.67; P = 0.0007). In CANTAM, adverse events were reported for 17.7% (95% CI 16.3, 19.2; 460/2599) of patients, most commonly vomiting (5.4% [95% CI 4.6, 6.4; 141/2599]), mainly following the first dose, (4.5% [117/2599]), with all patients successfully re-dosed, and pyrexia (5.4% [95% CI 4.6, 6.3; 140/2599]). In the two comparative clinical trials, Day 28 ACPR in the per-protocol population for PA was 97.1% (95% CI 94.6, 98.6; 329/339) and 100% (95% CI 99.3, 100; 514/514) versus 98.8% (95% CI 95.7, 99.9; 165/167) and 98.4% (95% CI 95.5, 99.7; 188/191) for AL, respectively. In CANTAM, PA clinical effectiveness was 98.0% (95% CI 97.3, 98.5; 2273/2320).ConclusionsAnti-malarial treatment with PA paediatric granules administered once daily for 3 days was well tolerated in children and displayed good clinical efficacy in clinical trials, with effectiveness confirmed in a real-world study.Trial registration Clinicaltrials.gov: SP-C-003-05: identifier NCT00331136; SP-C-007-07: identifier NCT0541385; SP-C-021-15: identifier NCT03201770. Pan African Clinical Trials Registry: SP-C-013-11: identifier PACTR201105000286876

Determination of the Prevalence of Different Brands of Fixed Dose Artemether/Lumefantrine Tablets Sold in Pharmacies in Uganda

Substandard, counterfeit and falsified antimalarial agents are a big challenge to effective malaria elimination interventions mainly in developing countries. In low-and middle-income countries (LMICs), the quality of antimalarial agents inclusive of AL is affected by several factors including insufficient regulation porous borders and limited funds. This study therefore focused evaluation of quality of different brands of fixed dose artemether/ lumefantrine tablets sold in Ugandan Pharmacies. This was an experimental study conducted using AL tablets obtained from different pharmacies in the different cities of Uganda purchased using mystery shopper method. The samples were screened for quality using visual inspection, assessed different physical quality parameters like weight variation, friability, disintegration and dissolution and content assay tests were also done both for the brands from the pharmacies and their correspondent LTR. The assay test was done using HPLC technique USP method. The samples were considered substandard if the API content was outside 90-110% range of the label claim. Data was analysed using descriptive statistics and presented as means with standard deviations and frequencies. 400 AL samples were collected from the different Pharmacies in the different cities and the corresponding LTRs in the strengths of 20/120, 60/360 and 80/480 with commonest brands Lumartem, Lumaren and Artefan. The presence of A/L brands that are unregistered and the total assay failure of the brands of 18% for the AL tablets purchased causes alarm. Keywords: Artemether lumefantrine, quality, tablets, prevalence

Effectiveness of artemether-lumefantrine for treating uncomplicated malaria in low- and high-transmission areas of Ghana.

Artemisinin-based combination therapy (ACT) has been effective in the supervised treatment of uncomplicated malaria in Ghana. Since ACT usage is primarily unsupervised, this study aimed to determine the effectiveness of artemether-lumefantrine (AL) for treating malaria patients in two transmission settings in Ghana. Eighty-four individuals with uncomplicated Plasmodium falciparum malaria were recruited from Lekma Hospital (LH) in Accra (low-transmission area; N = 28), southern Ghana, and King's Medical Centre (KMC) in Kumbungu (high-transmission area; N = 56), northern Ghana. Participants were followed up for 28days after unsupervised treatment with AL. The presence of asexual parasites was determined by microscopic examination of Giemsa-stained blood smears. Plasmodium species identification was confirmed using species-specific primers targeting the 18S rRNA gene. Parasite recrudescence or reinfection was determined by genotyping the Pfmsp 1 and Pfmsp 2 genes. After AL treatment, 3.6% (2/56) of the patients from KMC were parasitaemic on day 3 compared to none from the LH patients. One patient from KMC with delayed parasite clearance on day 3 remained parasite-positive by microscopy on day 7 but was parasite-free by day 14. While none of the patients from LH experienced parasite recurrence during the 28-day follow-up, three and two patients from KMC had recurrent parasitaemia on days 21 and 28, respectively. Percentage reduction in parasite densities from day 1, 2, and 3 for participants from the KMC was 63.2%, 89.5%, and 84.5%. Parasite densities for participants from the LH reduced from 98.2%, 99.8% on day 1, and 2 to 100% on day 3. The 28-day cumulative incidence rate of treatment failure for KMC was 12.8% (95% confidence interval: 1.9-23.7%), while the per-protocol effectiveness of AL in KMC was 89.47%. All recurrent cases were assigned to recrudescence after parasite genotyping by Pfmsp 1 and Pfmsp 2. While AL is efficacious in treating uncomplicated malaria in Ghana, when taken under unsupervised conditions, it showed an 89.4% PCR-corrected cure rate in northern Ghana, which is slightly below the WHO-defined threshold.

Determination of Concentration of Active Pharmaceutical Ingredients in Different Brands of Artemether/Lumefantrine Tablets Sold in the Pharmacies in Uganda

Substandard, counterfeit and falsified antimalarial agents are a big challenge to effective malaria elimination interventions mainly in developing countries. In low-and middle-income countries (LMICs), the quality of antimalarial agents inclusive of AL is affected by several factors including insufficient regulation porous borders and limited funds. This study therefore focused evaluation of quality of different brands of fixed dose artemether/ lumefantrine tablets sold in Ugandan Pharmacies. This was an experimental study conducted using AL tablets obtained from different pharmacies in the different cities of Uganda purchased using mystery shopper method. The samples were screened for quality using visual inspection, assessed different physical quality parameters like weight variation, friability, disintegration and dissolution and content assay tests were also done both for the brands from the pharmacies and their correspondent LTR. The assay test was done using HPLC technique USP method. The samples were considered substandard if the API content was outside 90-110% range of the label claim. Data was analysed using descriptive statistics and presented as means with standard deviations and frequencies. Out of the 16 brands in the study, 14 brands (88%) passed the artemether assay and two brands failed at 89.8% and 110.2% of declared artemether content. For Lumefantrine assay, out of the 16 brands in the study, 14 brands (88%) passed the Lumefantrine assay except two brands (12%). The presence of A/L brands that are unregistered and the total assay failure of the brands of 18% for the AL tablets purchased causes alarm and the total assay failure of the brands of 18% for the AL tablets purchased calls for NDA to intensify on its operations to find out the conformity of the pharmacies to selling only registered medicines. Keywords: Artemether Lumefantrine, Quality, Tablets

Efficacy and safety of Artemisinin Combination Therapy for the treatment of uncomplicated Plasmodium falciparum malaria across international borders of India.

Malaria due to Plasmodium falciparum (Pf) remains a major public threat in India. Artemisinin-based combination therapy (ACT) has been the country's first-line drug for uncomplicated Pf malaria. In 2013-2014, Artesunate plus sulfadoxine (AS+SP) was replaced by Artemether Lumefantrine (AL) as the first- line antimalarial in North East (NE) states of the country which are endemic for Pf malaria. Regular monitoring of antimalarial drugs is of utmost importance to achieve the goal of elimination. This study aimed to assess the efficacy and safety of ACT for treating uncomplicated Pf malaria in the NE states of India. A prospective study of 28-day follow-up was conducted to monitor the efficacy and safety of AL from 2018-2019 in four districts, Udalgiri, Meghalaya, Lawngtlai, and Dhalai of NE, India. The clinical and parasitological response and the polymorphism analysis of the Pfdhps, P/dhfr, and Pfkelch 13 gene were evaluated. A total of 234 patients were enrolled in the study out of 216 patients who completed the follow-up to 28 days. One-hundred percent adequate clinical and parasitological responses (ACPR) were observed with polymerase chain reaction (PCR) correction. The genotype results suggest no recrudescence in the treatment-failure patients. The classical single nucleotide polymorphisms (SNP) in the Pfdhfr gene was S108N (94.9%), followed by C59R (91.5%), whereas, in the Pfdhps gene, the common SNP was A437G (79.6%), followed by S3436A. No associated or validated mutations were found in the propeller region of the PfKelch13 gene. AL was efficacious and safe in uncomplicated P. falciparum malaria in North East India. In contrast, mutations in the genes responsible for sulfadoxine and pyrimethamine resistance have been fixed in northeast India's population.

Meta-Analysis of Data from Four Clinical Trials in the Ivory Coast Assessing the Efficacy of Two Artemisinin-Based Combination Therapies (Artesunate-Amodiaquine and Artemether-Lumefantrine) between 2009 and 2016.

The combinations of artemether-lumefantrine (AL) and artesunate-amodiaquine (ASAQ) are used as first-line treatments for uncomplicated malaria in the Ivory Coast. Different studies document the efficacy of two artemisinin-based combination therapies (ACTs) (AL and ASAQ) in the Ivory Coast. However, there is no meta-analysis examining the data set of these studies. The purpose of this work was to determine the prevalence of malaria treatment failure cases in randomized control trials with two artemisinin-based combination therapies (AL versus ASAQ) in the Ivory Coast between 2009 to 2016. This study is a meta-analysis of data from the results of four previous multicenter, open-label, randomized clinical trial studies evaluating the clinical and parasitological efficacy of artemether-lumefantrine and artesunate-amodiaquine conducted between 2009 and 2016 following World Health Organization (WHO) protocol at sentinel sites in the Ivory Coast. These drug efficacy data collected between 2009 and 2016 were analyzed. During these studies, to distinguish between recrudescence and new infection, molecular genotyping of genes encoding merozoite surface protein 1 and 2 was carried out using nested polymerase chain reaction (PCR). A total of 1575 patients enrolled in the four studies, including 768 in the AL arm and 762 in the ASAQ arm, which were fully followed either for 28 days or 42 days according to WHO protocol. The adequate clinical and parasitological response (ACPR) was higher than 95% in the two groups (intention to treat (ITT): AL = 96.59% and ASAQ = 96.81; Per Protocol (PP): AL = 99.48% and ASAQ = 99.61%) after PCR correction at day 28. Aggregate data analysis (2009-2016) showed that at day 28, the proportions of patients with recurrent infection was higher in the AL group (ITT: 3.79%, PP: 3.9%) than in the ASAQ group (ITT: 2.17%, PP: 2.23%). After PCR correction, most treatment failures were classified as new infections (AL group (ITT: 0.13%, PP: 0.13%); ASAQ group (ITT: 0.39%, PP: 0.39%). The recrudescent infections rate was high, at 0.39% compared to 0.13% for ASAQ and AL, respectively, for both ITT and PP, no significant difference. However, the Kaplan-Meier curve of cumulative treatment success showed a significant difference between the two groups after PCR from 2012-2013 (p = 0.032). Overall, ASAQ and AL have been shown to be effective drugs for the treatment of uncomplicated P. falciparum malaria in the study areas, 14 years after deployment of these drugs.

Ethanol extract of aloe vera ameliorates Artemether-Lumefantrine-induced reproductive toxicity in adult male Albino rats (Wistar Strain).

Artemether-Lumefantrine (AL) is one of the alternative drugs used in treating malaria - an endemic scourge in Africa. AL has been reported to generate free radicals with long term use implicated in testicular pathologies. The antioxidative properties of Aloe vera (AV) has been well documented. This study investigated the ameliorative effect of ethanol extract of Aloe Vera on Artemether-Lumefantrine induced testicular toxicity. Thirty adult male albino rats were randomly divided into 5 groups (Control, AL-dosed, AV-dosed, AL+AV concurrently administered and AV-pretreated). Spermiogram, serum testosterone, testicular histopathology and inducible nitric oxide synthase (iNOS) immunohistochemistry were carried out. AL-dosed rats had poor spermiogram indices which were greatly improved in AV-dosed and AV-pretreated rats. These also corresponded with the testicular histopathology observations and were further buttressed by oxidative stress marker (iNOS) as AL-dosed rats had higher signal intensity compared to the control and AV-pretreated rats. Authors posit that concurrent administration of AV and AL protected testicular architecture while pretreating with AV prior AL administration improved the spermiogram. AL induces testicular pathology, thus should be used with care in male subjects. AV can confer a level of protection against these defects if used prior to administration of the drug.

Factors affecting haemoglobin dynamics in African children with acute uncomplicated Plasmodium falciparum malaria treated with single low-dose primaquine or placebo

BackgroundSingle low-dose primaquine (SLDPQ) effectively blocks the transmission of Plasmodium falciparum malaria, but anxiety remains regarding its haemolytic potential in patients with glucose-6-phopshate dehydrogenase (G6PD) deficiency. We, therefore, examined the independent effects of several factors on haemoglobin (Hb) dynamics in falciparum-infected children with a particular interest in SLDPQ and G6PD status.MethodsThis randomised, double-blind, placebo-controlled, safety trial was conducted in Congolese and Ugandan children aged 6 months–11 years with acute uncomplicated P. falciparum and day (D) 0 Hbs ≥ 6 g/dL who were treated with age-dosed SLDPQ/placebo and weight-dosed artemether lumefantrine (AL) or dihydroartemisinin piperaquine (DHAPP). Genotyping defined G6PD (G6PD c.202T allele), haemoglobin S (HbS), and α-thalassaemia status.Multivariable linear and logistic regression assessed factor independence for continuous Hb parameters and Hb recovery (D42 Hb > D0 Hb), respectively.ResultsOne thousand one hundred thirty-seven children, whose median age was 5 years, were randomised to receive: AL + SLDPQ (n = 286), AL + placebo (286), DHAPP + SLDPQ (283), and DHAPP + placebo (282). By G6PD status, 284 were G6PD deficient (239 hemizygous males, 45 homozygous females), 119 were heterozygous females, 418 and 299 were normal males and females, respectively, and 17 were of unknown status.The mean D0 Hb was 10.6 (SD 1.6) g/dL and was lower in younger children with longer illnesses, lower mid-upper arm circumferences, splenomegaly, and α-thalassaemia trait, who were either G6PDd or heterozygous females. The initial fractional fall in Hb was greater in younger children with higher D0 Hbs and D0 parasitaemias and longer illnesses but less in sickle cell trait. Older G6PDd children with lower starting Hbs and greater factional falls were more likely to achieve Hb recovery, whilst lower D42 Hb concentrations were associated with younger G6PD normal children with lower fractional falls, sickle cell disease, α-thalassaemia silent carrier and trait, and late treatment failures. Ten blood transfusions were given in the first week (5 SLDPQ, 5 placebo).ConclusionsIn these falciparum-infected African children, posttreatment Hb changes were unaffected by SLDPQ, and G6PDd patients had favourable posttreatment Hb changes and a higher probability of Hb recovery. These reassuring findings support SLDPQ deployment without G6PD screening in Africa.Trial registrationThe trial is registered at ISRCTN 11594437.

Adherence to national malaria treatment guidelines in private drug outlets: a cross-sectional survey in the malaria-endemic Kisumu County, Kenya

BackgroundMalaria prevalence in Kenya is 6%, with a three-fold higher prevalence in western Kenya. Adherence to malaria treatment guidelines improves care for suspected malaria cases and can reduce unnecessary anti-malarial use. Data on adherence to guidelines in retail drug outlets (DOs) is limited, yet approximately 50% of people with fever access treatment first in these outlets. This study assessed adherence to the national malaria treatment guidelines among DOs in a high transmission area of Western Kenya.MethodsIn a cross-sectional survey of DOs in Kisumu Central and Seme sub-counties in 2021, DO staff were interviewed using structured questionnaires to assess outlet characteristics (location, testing services), staff demographics (age, sex, training), and health system context (supervision, inspection). Mystery shoppers (research assistants disguised as clients) observed malaria management practices and recorded observations on a standardized tool. Adherence was defined as dispensing artemether-lumefantrine (AL) to patients with a confirmed positive test, accompanied by appropriate medication counseling. Logistic regression was used to test for association between adherence to guidelines and DO-related factors.ResultsNone of the 70 DOs assessed had a copy of the guidelines, and 60 (85.7%) were in an urban setting. Staff adhered to the guidelines in 14 (20%) outlets. The odds of adherence were higher among staff who had a bachelor’s degree {odds ratio (OR) 6.0, 95% confidence interval (95% CI) 1.66–21.74}, those trained on malaria rapid diagnostic test (RDT) {OR 4.4, 95% CI 1.29–15.04}, and those who asked about patient’s symptoms {OR 3.6, 95% CI 1.08–12.25}. DOs that had higher odds of adherence included those with functional thermometers {OR 5.3, 95% CI 1.46–19.14}, those recently inspected (within three months) by Pharmacy and Poisons Board (PPB) {OR 9.4, 95% CI 2.55–34.67}, and those with all basic infrastructure {OR 3.9, 95% CI 1.01–15.00}. On logistic regression analysis, recent PPB inspection {adjusted OR (AOR) 4.6, 95% CI 1.03–20.77} and malaria RDT-trained staff (aOR 4.5, 95% CI 1.02–19.84) were independently associated with adherence.ConclusionMost outlets didn’t adhere to malaria guidelines. Regular interaction with regulatory bodies could improve adherence. Ministry of Health should enhance private sector engagement and train DOs on RDT use.

Efficacy and safety of pyronaridine-artesunate (PYRAMAX) for the treatment of P. falciparum uncomplicated malaria in African pregnant women (PYRAPREG): study protocol for a phase 3, non-inferiority, randomised open-label clinical trial

IntroductionMalaria 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;...

Variation in neutrophil levels and artemisinin-based combination therapy efficacy in West-Africa.

Polymorphonuclear neutrophils (PMN) are involved in pathogen clearance by phagocytosis. However, the role of PMNs in the efficacy of artemisinin-based combination therapy (ACT) is poorly understood. In a prospective longitudinal in vivo study, neutrophil rates were compared with malaria carriage after treatment with different ACTs: Artemether - lumefantrine (AL), Artesunate - amodiaquine (ASAQ), Dihydroartemisinin - piperaquine (DP) or Pyronaridine artesunate (PA). The study cases were classified as having neutropenia, normal neutrophil levels or neutrophilia depending on the level of neutrophils in the blood. This study included 3148 patients and was analyzed using R. On day 7, only four patients in the neutropenia group and treated with AL had a malaria positive blood smear based on microscopy. On day 28, the rate of recurrent parasitemia in the AL arm was significantly higher in neutropenia patients (50.9%) than in patients with normal rates of neutrophils (43.1%) or in those with neutrophilia (6.0%) (p < 0.001). In ASAQ arm, the rate of recurrent Plasmodium falciparum parasitemia was 58.8% in the neutropenia group versus 29.4% in patients with normal rates of neutrophils and 11.8% in patients with neutrophilia (p < 0.001). No patient treated with DP with normal neutrophil counts or neutrophilia was carrying malaria parasites on day 28. Among the 15 patients with parasitemia on day 28 in the PA arm, 11 (73.33%) had neutropenia while 4 (26.67%) had a normal neutrophil count (p < 0.001). Patients with neutropenia had higher rates of recurrent P. falciparum parasitemia after ACT.

Increasing Prevalence of Artemisinin-Resistant HRP2-Negative Malaria in Eritrea

BackgroundAlthough the clinical efficacy of antimalarial artemisinin-based combination therapies in Africa remains high, the recent emergence of partial resistance to artemisinin in Plasmodium falciparum on the continent is troubling, given the lack of alternative treatments.MethodsIn this study, we used data from drug-efficacy studies conducted between 2016 and 2019 that evaluated 3-day courses of artemisinin-based combination therapy (artesunate–amodiaquine or artemether–lumefantrine) for uncomplicated malaria in Eritrea to estimate the percentage of patients with day-3 positivity (i.e., persistent P. falciparum parasitemia 3 days after the initiation of therapy). We also assayed parasites for mutations in Pfkelch13 as predictive markers of partial resistance to artemisinin and screened for deletions in hrp2 and hrp3 that result in variable performance of histidine rich protein 2 (HRP2)–based rapid diagnostic tests for malaria.ResultsWe noted an increase in the percentage of patients with day-3 positivity from 0.4% (1 of 273) in 2016 to 1.9% (4 of 209) in 2017 and 4.2% (15 of 359) in 2019. An increase was also noted in the prevalence of the Pfkelch13 R622I mutation, which was detected in 109 of 818 isolates before treatment, from 8.6% (24 of 278) in 2016 to 21.0% (69 of 329) in 2019. The odds of day-3 positivity increased by a factor of 6.2 (95% confidence interval, 2.5 to 15.5) among the patients with Pfkelch13 622I variant parasites. Partial resistance to artemisinin, as defined by the World Health Organization, was observed in Eritrea. More than 5% of the patients younger than 15 years of age with day-3 positivity also had parasites that carried Pfkelch13 R622I. In vitro, the R622I mutation conferred a low level of resistance to artemisinin when edited into NF54 and Dd2 parasite lines. Deletions in both hrp2 and hrp3 were identified in 16.9% of the parasites that carried the Pfkelch13 R622I mutation, which made them potentially undetectable by HRP2-based rapid diagnostic tests.ConclusionsThe emergence and spread of P. falciparum lineages with both Pfkelch13-mediated partial resistance to artemisinin and deletions in hrp2 and hrp3 in Eritrea threaten to compromise regional malaria control and elimination campaigns. (Funded by the Bill and Melinda Gates Foundation and others; Australian New Zealand Clinical Trials Registry numbers, ACTRN12618001223224, ACTRN12618000353291, and ACTRN12619000859189.)

Antimalarial drug efficacy and resistance in malaria-endemic countries in HANMAT-PIAM_net countries of the Eastern Mediterranean Region 2016-2020: Clinical and genetic studies.

The World Health Organization recommends regular monitoring of the efficacy of nationally recommended antimalarial drugs. We present the results of studies on the efficacy of recommended antimalarials and molecular markers of artemisinin and partner resistance in Afghanistan, Pakistan, Somalia, Sudan and Yemen. Single-arm prospective studies were conducted to evaluate the efficacy of artesunate-sulfadoxine-pyrimethamine (ASSP) in Afghanistan and Pakistan, artemether-lumefantrine (AL) in all countries, or dihydroartemisinin-piperaquine (DP) in Sudan for the treatment of Plasmodium falciparum. The efficacy of chloroquine (CQ) and AL for the treatment of Plasmodium vivax was evaluated in Afghanistan and Somalia, respectively. Patients were treated and monitored for 28 (CQ, ASSP and AL) or 42 (DP) days. Polymerase chain reaction (PCR)-corrected cure rate and parasite positivity rate at Day 3 were estimated. Mutations in the P. falciparum kelch 13 (Pfk13) gene and amplifications of plasmepsin (Pfpm2) and multidrug resistance-1 (Pfmdr-1) genes were also studied. A total of 1680 (249 for ASSP, 1079 for AL and 352 for DP) falciparum cases were successfully assessed. A PCR-adjusted ASSP cure rate of 100% was observed in Afghanistan and Pakistan. For AL, the cure rate was 100% in all but four sites in Sudan, where cure rates ranged from 92.1% to 98.8%. All but one patient were parasite-free at Day 3. For P. vivax, cure rates were 98.2% for CQ and 100% for AL. None of the samples from Afghanistan, Pakistan and Yemen had a Pfk13 mutation known to be associated with artemisinin resistance. In Sudan, the validated Pfk13 R622I mutation accounted for 53.8% (14/26) of the detected non-synonymous Pfk13 mutations, most of which were repeatedly detected in Gadaref. A prevalence of 2.7% and 9.3% of Pfmdr1 amplification was observed in Pakistan and Yemen, respectively. High efficacy of ASSP, AL and DP in the treatment of uncomplicated falciparum infection and of CQ and AL in the treatment of P. vivax was observed in the respective countries. The repeated detection of a relatively high rate of Pfk13 R622I mutation in Sudan underscores the need for close monitoring of the efficacy of recommended ACTs, parasite clearance rates and Pfk13 mutations in Sudan and beyond. Registration numbers of the trials: ACTRN12622000944730 and ACTRN12622000873729 for Afghanistan, ACTRN12620000426987 and ACTRN12617001025325 for Pakistan, ACTRN12618001224213 for Somalia, ACTRN12617000276358, ACTRN12622000930785 and ACTRN12618001800213 for Sudan and ACTRN12617000283370 for Yemen.

Healthcare provider and drug dispenser knowledge and adherence to guidelines for the case management of malaria in pregnancy in the context of multiple first-line artemisinin-based combination therapy in western Kenya

BackgroundConcerns 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.MethodsFrom 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.ResultsOf 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.ConclusionsKnowledge 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.

Evaluation of the Efficacy of Artemether/Lumefantrine/Doxycycline Combination against Plasmodium berghei in Mice

Background: Malaria is common in regions like sub-Saharan Africa and South East Asia, where it results in millions of mortalities per year. Resistance to currently available antimalarials further compounds the problem. Drug combination has been demonstrated to be effective in overcoming resistance to antimalarials. This study aimed to assess the efficacy of the combination of Artemether/Lumefantrine (AL) and Doxycycline (DX) against Plasmodium berghei infection in mice. Methods: Thirty Adult Swiss albino mice were inoculated with the chloroquine (CQ)-sensitive P. berghei NK65 strain. The curative test involved oral administration of any of DX, AL, AL/DX, or Chloroquine (CQ) to mice with established infections, while the suppressive test was performed by treating mice shortly after parasite inoculation. Parasitemia levels were monitored using thin smears stained with Giemsa solution. Mean Survival Time (MST) was determined for each group. Results: In the curative test, DX, AL, and AL/DX exhibited parasitemia inhibitions of 81.4%, 94.5%, and 93.2%, respectively, while CQ achieved 93.5% inhibition. MST was significantly extended by DX, AL, and AL/DX treatments compared to negative control (NC). In the suppressive test, parasitemia inhibitions were 79.9%, 96.1%, 95.5%, and 94.9% for DX, AL, AL/DX, and CQ, respectively. The administration of DX, AL, and AL/DX also significantly prolonged MST compared to NC. Conclusion: The study demonstrates that the drug combination, particularly AL/DX, exhibits significant antimalarial effects in both curative and suppressive tests. The combination treatments led to substantial reductions in parasitemia levels and extended mean survival time, indicating their potential as effective antimalarial strategies. These findings highlight the promising role of drug combinations in addressing malaria infections and suggest avenues for further investigation and development of combination therapies.

Therapeutic efficacy of artesunate–amodiaquine and artemether–lumefantrine for the treatment of uncomplicated falciparum malaria in Chad: clinical and genetic surveillance

BackgroundArtesunate–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).MethodsA 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.ResultsBy 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.ConclusionThe 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

­Pharmacokinetics of antimalarial drugs used to treat uncomplicated malaria in breastfeeding mother-infant pairs: An observational pharmacokinetic study

Background: Data surrounding the exposure of the breastfed infant to drugs and any associated risks are sparse. Drugs usually are transferred to milk in small quantities, and many have been used without obviously noticeable infant toxicity for many years – this lack of a ‘safety signal’ has further reduced the interest in studying mother-to-infant transfer of the drugs. In sub-Saharan Africa, pregnant women are at risk of Plasmodium falciparum infection, and one in four women have evidence of placental infection at the time of delivery. Artemisinin-based combination therapies (ACTs), primarily artemether-lumefantrine (AL), are the current first-line treatment for uncomplicated Plasmodium falciparum malaria, with the same dosing recommendations in breastfeeding women as those in the adult population. Dihydroartemisinin-piperaquine (DP) is routinely used as an alternative to AL in Uganda. However, lactation pharmacokinetics (PK) of ACTs are unknown. Pharmacokinetic characterization of anti-malarial transfer to breast milk and breastfed infants is crucial in understanding the potential consequences to the infant, in terms of therapeutic- and prophylactic effects as well as potential toxicity. Methods: This observational study will enroll 30 mother-infant pairs, and aims to characterize the breastmilk transfer of antimalarial medications (AL and DP) to infants when these ACTs are administered to mothers as part of treatment for uncomplicated malaria. In addition, we will assess the mental health of the breastfeeding mothers enrolled as well as the well-being of their children. PK samples of maternal blood, breastmilk and breastfeeding infant’s blood will be obtained at specific times points. Pharmacokinetic data will be analyzed using a population pharmacokinetic approach. Conclusions: We anticipate that findings from this research will guide to develop a PK model describing lumefantrine and piperaquine disposition and will provide a framework to foster other lactation pharmacokinetic studies in different disease areas.

Plasmodium falciparum Multidrug Resistance-1 (pfmdr1) Gene Mutation in Adults Malaria Patients Attending Murtala Muhammad Specialist Hospital Kano, Northwest Nigeria

Suspicion of failure in the effectiveness of artemisinin-based combination therapies (currently the first-line treatment of malaria, worldwide) is leading to the unofficial use of alternative antimalarials, including chloroquine and sulfadoxine/pyrimethamine in Kano state northwestern Nigeria. To facilitate evidence-based resistance management, antimalarial resistance mutations were investigated in Plasmodium falciparum multidrug resistance-1 (pfmdr1) gene. Hundred adult patients comprising 43 males and 57 females were recruited for the study. The mean age of participants is 36.4 years, minimum and maximum ages were 16 and 60 years respectively, while 41% of them fall within the range of 16 to 30 years. Blood isolates were then analyzed for the presence of malaria parasite using microscopy, the results show a high prevalence of P. falciparum infection in the subject (30%). Pfmdr1 gene, a molecular marker of artemisinin resistance, was successfully sequenced in 21 out of 100 P. falciparum isolates collected from recruited participants. Pfmdr1 mutations were found in 19.5% (4/33) of the samples isolated. The prevalence of the Pfmdr1 N86Y allele was found in 4 samples whilst Y184F and D1246Y were not detected. A total of 4 non-synonymous mutations at codon N86Y were detected. The presence of these mutations highlights the challenges for malaria treatment in Kano state, northwestern Nigeria using antimalarials such as artemether lumefantrine, mefloquine, amodiaquine quinine and lumefantrine.

Hepatoprotective effect of Vernonia amygdalina and Ocimum gratissimum on Wistar rats exposed to long-term administration of artemisinin-based combination therapies

In this study the protective effect of Vernonia amygdalina (VA) and Ocimum gratissimum (OG) on rats exposed to long term oral administration of artesunate-amodiaquine and arthemeter-lumefantrine were investigated. Forty-two albino rats were divided into seven groups. They were given the drugs, artesunate amodiaquine (AA) and artemether lumefantrine (AL) base on their body weight. Group 1: Control, received distilled water, group 2, received of 2.86 mg/7.7 mg AA, group 3, received of 1.14 mg/6.86 mg AL, group 4 received of 2.86 mg/7.7 mg AA + 200 mg VA, group 5 received of 1.14 mg/6.86 mg AL + 200 mg VA, group 6 received of 2.86 mg/7.7 mg AA + 200 mg OG and group 7 received of 1.14 mg/6.86 mg AL + 200 mg OG. The animals were sacrificed and blood samples obtained through cardiac puncture for biochemical investigations. Biochemical assay for total protein, albumin, total bilirubin, direct bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma glutamyltransferase (γ-GT) were done. Co-administration of artesunate-amodiaquine and arthemeter-lumefantrine significantly decreased (P&lt; 0.05) total protein and albumin while there was significant increase (P&lt; 0.05) in total bilirubin, direct bilirubin, AST, ALT, ALP and γ-GT when compared with control group. The administration of VA and OG significantly increased the total protein and albumin and significantly decreased (P&lt; 0.05) total bilirubin and liver enzymes when compared with control group. The results indicate hepatic injury in the rats exposed to long term administration of artemisinin-based combination therapies (ACTs) which was reversed by the administration of VA and OG. There is need for caution while taking ACTs as malaria chemotherapy.