Treatment Of Falciparum Malaria Research Articles

Artemisinin Derivatives Based Therapeutic Combinations for The Treatment of Uncomplicated Plasmodium Falciparum Malaria: Find-Ings of a Meta-Analysis of Surveys Carried Out in Senegal

Artemisinin Derivatives Based Therapeutic Combinations for The Treatment of Uncomplicated Plasmodium Falciparum Malaria: Find-Ings of a Meta-Analysis of Surveys Carried Out in Senegal

Fitness Loss under Amino Acid Starvation in Artemisinin-Resistant Plasmodium falciparum Isolates from Cambodia

Artemisinin is the most rapidly effective drug for Plasmodium falciparum malaria treatment currently in clinical use. Emerging artemisinin-resistant parasites pose a great global health risk. At present, the level of artemisinin resistance is still relatively low with evidence pointing towards a trade-off between artemisinin resistance and fitness loss. Here we show that artemisinin-resistant P. falciparum isolates from Cambodia manifested fitness loss, showing fewer progenies during the intra-erythrocytic developmental cycle. The loss in fitness was exacerbated under the condition of low exogenous amino acid supply. The resistant parasites failed to undergo maturation, whereas their drug-sensitive counterparts were able to complete the erythrocytic cycle under conditions of amino acid deprivation. The artemisinin-resistant phenotype was not stable, and loss of the phenotype was associated with changes in the expression of a putative target, Exp1, a membrane glutathione transferase. Analysis of SNPs in haemoglobin processing genes revealed associations with parasite clearance times, suggesting changes in haemoglobin catabolism may contribute to artemisinin resistance. These findings on fitness and protein homeostasis could provide clues on how to contain emerging artemisinin-resistant parasites.

Efficacy of artemether-lumefantrine for the treatment of uncomplicated Plasmodium falciparum malaria in Nepal

BackgroundThe national treatment guidelines of Nepal have adopted Artemisinin Combination Therapies (ACTs) for the treatment of uncomplicated falciparum malaria since 2004. Emergence of Artemisinin resistance in the Greater Mekong Sub-region (GMS) and beyond may become a threat for Nepal as well. The main objective of this study was to assess the therapeutic efficacy of antimalarial drug artemether-lumefantrine in uncomplicated P. falciparum infected patients at health centers/hospitals treated over the period of 2 years (2013–2014).MethodsGiemsa stained thick and thin smears, prepared from uncomplicated falciparum malaria patients who visited the selected sentinel sites in Nepal during 2013 to 2014 and met the inclusion criteria that included parasitemia (1000–10,000 /μL of blood), were evaluated until 28 days after ACTs treatment, following a World Health Organization (WHO) therapeutic efficacy protocol. Based on the re-occurrence of fever and resurge in parasitemia, the study patients were classified as resistant or susceptible. Blood specimens on filter papers were further analyzed by Polymerase Chain Reaction (PCR), specifically for the K13 propeller gene mutation (a recently identified molecular marker for ACT resistance).ResultsA total of 56,013 suspected malaria cases were screened for this study. Of which, 120 (0.21%) were infected with falciparum malaria. Out of 120, 28 cases of P. falciparum (28/120; 23.33%) were enrolled in the study, of which 24 cases completed the post-treatment follow up for 28 days. Only one case out of 24 (4%) was identified as a late treatment failure (LTF). K13 mutation, a proxy indicator for ACT resistance in parasites, was not detected on the day 1, which indicates resistance had not yet reached the molecular level.ConclusionOnly one case of late treatment failure was identified in this study. ACT combination using artemether-lumefantrine was still effective for the treatment of uncomplicated falciparum malaria in Nepal. A close monitoring and supervision for ACT resistance is essential for future malaria treatment in Nepal.

Efficacy of artesunate\u2013amodiaquine in the treatment of falciparum uncomplicated malaria in Madagascar

BackgroundSince 2006, the artemisinin-based combination therapy (ACT) are recommended to treat uncomplicated malaria including non Plasmodium falciparum malaria in Madagascar. Artesunate–amodiaquine (ASAQ) and artemether–lumefantrine are the first- and second-line treatment in uncomplicated falciparum malaria, respectively. No clinical drug efficacy study has been published since 2009 to assess the efficacy of these two artemisinin-based combinations in Madagascar, although the incidence of malaria cases has increased from 2010 to 2016. In this context, new data about the efficacy of the drug combinations currently used to treat malaria are needed.MethodsTherapeutic efficacy studies evaluating the efficacy of ASAQ were conducted in 2012, 2013 and 2016 among falciparum malaria-infected patients aged between 6 months and 56 years, in health centres in 6 sites representing different epidemiological patterns. The 2009 World Health Organization protocol for monitoring anti-malarial drug efficacy was followed.ResultsA total of 348 enrolled patients met the inclusion criteria including 108 patients in 2012 (n = 64 for Matanga, n = 44 for Ampasipotsy), 123 patients in 2013 (n = 63 for Ankazomborona, n = 60 for Anjoma Ramartina) and 117 patients in 2016 (n = 67 for Tsaratanana, n = 50 for Antanimbary). The overall cumulative PCR-corrected day 28 cure rate was 99.70% (95% IC 98.30–99.95). No significant difference in cure rates was observed overtime: 99.02% (95% IC 94.65–99.83) in 2012; 100% (95% IC 96.8–100) in 2013 and 100% (95% IC 96.65–100) in 2016.ConclusionThe ASAQ combination remains highly effective for the treatment of uncomplicated falciparum malaria in Madagascar.

High efficacy of artemether\u2013lumefantrine and dihydroartemisinin\u2013piperaquine for the treatment of uncomplicated falciparum malaria in Muheza and Kigoma Districts, Tanzania

BackgroundArtemether–lumefantrine (AL) is the recommended first-line artemisinin-based combination therapy (ACT) for the treatment of uncomplicated falciparum malaria in most of the malaria-endemic countries, including Tanzania. Recently, dihydroartemisinin–piperaquine (DP) has been recommended as the alternative anti-malarial to ensure effective case management in Tanzania. This study assessed the parasite clearance rate and efficacy of AL and DP among patients aged 6 months to 10 years with uncomplicated falciparum malaria in two sites with different malaria transmission intensity.MethodsThis was an open-label, randomized trial that was conducted at two sites of Muheza Designated District Hospital and Ujiji Health Centre in Tanga and Kigoma regions, respectively. Patients meeting inclusion criteria were enrolled, treated with either AL or DP and followed up for 28 (extended to 42) and 42 (63) days for AL and DP, respectively. Parasite clearance time was monitored in the first 72 h post treatment and the clearance rate constant and half-life were calculated using an established parasite clearance estimator. The primary outcome was parasitological cure on days 28 and 42 for AL and DP, respectively, while secondary outcome was extended parasitological cure on days 42 and 63 for AL and DP, respectively.ResultsOf the 509 children enrolled (192 at Muheza and 317 at Ujiji), there was no early treatment failure and PCR uncorrected cure rates on day 28 in the AL group were 77.2 and 71.2% at Muheza and Ujiji, respectively. In the DP arm, the PCR uncorrected cure rate on day 42 was 73.6% at Muheza and 72.5% at Ujiji. With extended follow-up (to day 42 for AL and 63 for DP) cure rates were lower at Ujiji compared to Muheza (AL: 60.2 and 46.1%, p = 0.063; DP: 57.6 and 40.3% in Muheza and Ujiji, respectively, p = 0.021). The PCR corrected cure rate ranged from 94.6 to 100% for all the treatment groups at both sites. Parasite clearance rate constant was similar in the two groups and at both sites (< 0.28/h); the slope half-life was < 3.0 h and all but only one patient cleared parasites by 72 h.ConclusionThese findings confirm high efficacy of the first- and the newly recommended alternative ACT for treatments for uncomplicated falciparum malaria in Tanzania. The high parasite clearance rate suggests absence of suspected artemisinin resistance, defined as delayed parasite clearance.Trial registration This trial is registered at ClinicalTrials.gov under registration number NCT02590627

Effectiveness and safety of 3 and 5\xa0day courses of artemether\u2013lumefantrine for the treatment of uncomplicated falciparum malaria in an area of emerging artemisinin resistance in Myanmar

BackgroundArtemisinin resistance in Plasmodium falciparum has emerged and spread in Southeast Asia. In areas where resistance is established longer courses of artemisinin-based combination therapy have improved cure rates.MethodsThe standard 3-day course of artemether–lumefantrine (AL) was compared with an extended 5-day regimen for the treatment of uncomplicated falciparum malaria in Kayin state in South-East Myanmar, an area of emerging artemisinin resistance. Late parasite clearance dynamics were described by microscopy and quantitative ultra-sensitive PCR. Patients were followed up for 42 days.ResultsOf 154 patients recruited (105 adults and 49 children < 14 years) 78 were randomized to 3 days and 76 to 5 days AL. Mutations in the P. falciparum kelch13 propeller gene (k13) were found in 46% (70/152) of infections, with F446I the most prevalent propeller mutation (29%; 20/70). Both regimens were well-tolerated. Parasite clearance profiles were biphasic with a slower submicroscopic phase which was similar in k13 wild-type and mutant infections. The cure rates were 100% (70/70) and 97% (68/70) in the 3- and 5-day arms respectively. Genotyping of the two recurrences was unsuccessful.ConclusionDespite a high prevalence of k13 mutations, the current first-line treatment, AL, was still highly effective in this area of South-East Myanmar. The extended 5 day regimen was very well tolerated, and would be an option to prolong the useful therapeutic life of AL.Trial registration NCT02020330. Registered 24 December 2013, https://clinicaltrials.gov/NCT02020330

Efficacy of two artemisinin-based combinations for the treatment of malaria in pregnancy in India: a randomized controlled trial

BackgroundIn India, the recommended first-line treatment for malaria in the second and third trimester of pregnancy is artesunate + sulfadoxine-pyrimethamine (AS+SP). However, data on safety and efficacy of artemisinin-based combination therapy (ACT) in pregnancy is limited. This study assessed the safety and efficacy of AS+SP and artesunate + mefloquine (AS+MQ) for treatment of Plasmodium falciparum in pregnancy in India.MethodsThis open-label, randomized clinical trial was conducted from October 2010 to December 2013 at three sites in India (Ranchi and Jamshedpur in Jharkhand state, and Rourkela in Odisha state). Pregnant women in the second or third trimester who had P. falciparum mono-infection of any parasite density with or without fever were randomized to receive AS+SP or AS+MQ. Blood slides and filter paper samples for Polymerase Chain Reaction (PCR) were collected on days 0, 1, 2, 3, 14, 21, 28, 42 and 63 post treatment. Women were followed up at delivery and at day 42 postpartum.FindingsTwo hundred and forty-eight women of 7064 pregnant women (3.5%) who were screened at monthly antenatal clinics had a P. falciparum mono-infection and were randomized to receive AS+SP (125) or AS+MQ (123) and all of these women were included in the intention to treat (ITT) analysis. The primary endpoint of an adequate clinical and parasite response (ACPR) on day 63 was not available for 9 women who were counted as treatment failure in the ITT analysis. In the ITT population, the ACPR was 121/125 (96.8%; 95% Confidence interval (CI) 92.0–99.1%) in the AS+SP group and 117/123 (95.1%; 95% CI 89.7–98.2) in the AS+MQ group. Among the 239 women (121 from the AS+SP arm and 118 from the AS+MQ arm) who completed the day 63 follow up (per protocol analysis) the ACPR was 100% in the AS+SP group and 99.2% (117/118) in the AS+MQ group. There were five serious adverse events (SAE) among pregnant women (4 in the AS+SP group and 1 in the AS+MQ group) and 13 fetal/neonatal SAEs (7 in the AS+SP group and 6 in the AS+MQ) but none of them were related to the study drugs. A higher proportion of women in the AS+MQ arm reported vomiting within 7 days post-treatment than did women in the AS+SP arm (6.9 vs. 1.6%; p = 0.001).ConclusionBoth AS+SP and AS+MQ are safe and effective for treatment of uncomplicated falciparum malaria in pregnancy in India.Trial registrationCTRI This study is registered with Clinical Trial Registry India (CTRI), number CTRI/2009/091/001055. Date of Registration 11 January 2010, http://ctri.nic.in/Clinicaltrials/pmaindet2.php?trialid=1185&EncHid=&userName=anvikar

Artemeter-Lumefantrine therapeutic efficacy, safety and plasma levels in patients with uncomplicated falciparum malaria from the Colombian Pacific región

Introduction: In Colombia, the published studies for the treatment of uncomplicated Plasmodium falciparum malaria with Artemether-Lumefantrine are scarce. The aim of the study was to evaluate the therapeutic efficacy and safety profile of this combination.Methods: A clinical trial was performed in adults with uncomplicated P. falciparum malaria using the 28-day World Health Organization validated protocol. Patients received supervised antimalarial treatment and the primary efficacy endpoint was the clinical and parasitological response. Safety was assessed through adverse events surveillance and plasmatic levels of antimalarial drugs were measured.Results: 88 patients were included. Adequate clinical and parasitological response rate of 100% on day 28 was achieved in 84 patients, diagnosed by thick blood smear examination. There were four parasitological therapeutic failures (5%) detected by polymerase chain reaction.Discusion: Therapeutic efficacy similar to previous studies was established with a slight increase in therapeutic failure. The serum levels of the antimalarials were adequate and the few cases of therapeutic failure were not related.Conclusion: Treatment of uncomplicated P. falciparum malaria with Artemeter-Lumefantrine was effective and safe in the study population. All patients reached adequate plasma concentrations of the drugs; therapeutic failures were not associated with low blood levels of the drug clinical trial.

Clinical Pharmacology of the Antimalarial Artemisinin-Based Combination and other Artemisinins in Children

In 2010, there were estimated 219 million cases of malaria resulting in 666,000 deaths and two-thirds were children. Children are more vulnerable than adults to malaria parasites. In sub-Saharan African countries, maternal malaria is associated with up to 200,000 estimated infant deaths yearly. Malaria is caused by five Plasmodium parasites namely: Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale, Plasmodium malariae, and Plasmodium knowlesi. Of these, Plasmodium falciparum accounts for the majority of the burden of malaria infection in sub-Sahara African countries and is associated with most severe disease. Plasmodium vivax accounts for half of the malarial burden infection in South and East Asia and > 80% of the malarial infections in the America. The artemisinins are very potent and fast-acting antimalarials, inducing more rapid parasite clearance and fever resolution than any other currently used of antimalarial drugs. They are particularly well suited for the treatment of severe Plasmodium falciparum malaria. The standard treatment of malaria infection employs artemisinin-based combination therapy. This antimalarial drug increases treatment efficacy and reduces selection pressure for the emergence of drug resistance. Artemisinins cause a significant reduction of the parasite burden, with a reduction in the parasite population. Only three to four cycles (6 to 8 days) of treatment are required to remove all parasites from the blood. Artemisinins are formulated for oral, intramuscular, intravenous, and rectal routs. Bioavailability after oral dosing is ≤ 30%. The aim of this study is to review the published data on the clinical pharmacology of artemisinins in children.

Influence of abiotic elicitors on improvement production of artemisinin in cell culture of Artemisia annua L.

A significant sesquiterpene lactone used as a drug is artemisinin. It is definitely an anti-parasitic drug isolated from field-grown Artemisia annua L. a plant from Asteraceae family. It is the best treatment for Plasmodium falciparum malaria. Unfortunately, artemisinin content in A. annua is extremely low (0.01-0.8% dry weight). So, some researchers focused on enhancing artemisinin content either in tissue/cell culture or the whole plant of A. annua sp. The aims of the current study were the effect of plant growth regulators on callus production and improvement of artemisinin content in cell suspension culture of A. annua, an alternative to the whole plant using abiotic elicitors. For callus induction, an experiment was laid out as a factorial experiment with three factors (explant type, different concentrations of BAP and 2,4-D) based on completely randomized design with three replications. The maximum frequency of callus induction (100%) was found in leaf explant on MS medium with a combination of 2, 4-D (3 mg/l) and BAP (1.5 mg/l). Therefore, the best calli were used for cell suspension culture and the effects of GA3 and ABA as abiotic elicitors were evaluated on the improvement of artemisinin production. The results indicated that both ABA and GA3 increased artemisinin content (2.02 fold and 1.67 fold in comparison to control respectively) in cell suspension culture.

Efficacy of Artemisinin-Based Combination Treatments of Uncomplicated Falciparum Malaria in Under-Five-Year-Old Nigerian Children Ten Years Following Adoption as First-Line Antimalarials.

The efficacies of 3-day regimens of artemether-lumefantrine (AL), artesunate-amodiaquine (AA), and dihydroartemisinin-piperaquine (DHP) were evaluated in 910 children < 5 years old with uncomplicated malaria from six geographical areas of Nigeria. Parasite positivity 1 day and Kaplan-Meier estimated risk of persistent parasitemia 3 days after therapy initiation were both significantly higher, and geometric mean parasite reduction ratio 1 day after treatment initiation (PRRD1) was significantly lower in AL-treated children than in AA- and DHP-treated children. No history of fever, temperature > 38°C, enrollment parasitemia > 75,000 μL-1, and PRRD1 < 5,000 independently predicted persistent parasitemia 1 day after treatment initiation. Parasite clearance was significantly faster and risk of reappearance of asexual parasitemia after initial clearance was significantly lower in DHP-treated children. Overall, day 42 polymerase chain reaction-corrected efficacy was 98.3% (95% confidence interval [CI]: 96.1-100) and was similar for all treatments. In a non-compartment model, declines of parasitemias were monoexponential with mean terminal elimination half-life of 1.3 hours and unimodal frequency distribution of half-lives. All treatments were well tolerated. In summary, all three treatments evaluated remain efficacious treatments of uncomplicated malaria in young Nigerian children, but DHP appears more efficacious than AL or AA.

Artemether-lumefantrine dosing for malaria treatment in young children and pregnant women: A pharmacokinetic-pharmacodynamic meta-analysis.

BackgroundThe fixed dose combination of artemether-lumefantrine (AL) is the most widely used treatment for uncomplicated Plasmodium falciparum malaria. Relatively lower cure rates and lumefantrine levels have been reported in young children and in pregnant women during their second and third trimester. The aim of this study was to investigate the pharmacokinetic and pharmacodynamic properties of lumefantrine and the pharmacokinetic properties of its metabolite, desbutyl-lumefantrine, in order to inform optimal dosing regimens in all patient populations.Methods and findingsA search in PubMed, Embase, ClinicalTrials.gov, Google Scholar, conference proceedings, and the WorldWide Antimalarial Resistance Network (WWARN) pharmacology database identified 31 relevant clinical studies published between 1 January 1990 and 31 December 2012, with 4,546 patients in whom lumefantrine concentrations were measured. Under the auspices of WWARN, relevant individual concentration-time data, clinical covariates, and outcome data from 4,122 patients were made available and pooled for the meta-analysis. The developed lumefantrine population pharmacokinetic model was used for dose optimisation through in silico simulations. Venous plasma lumefantrine concentrations 7 days after starting standard AL treatment were 24.2% and 13.4% lower in children weighing <15 kg and 15–25 kg, respectively, and 20.2% lower in pregnant women compared with non-pregnant adults. Lumefantrine exposure decreased with increasing pre-treatment parasitaemia, and the dose limitation on absorption of lumefantrine was substantial. Simulations using the lumefantrine pharmacokinetic model suggest that, in young children and pregnant women beyond the first trimester, lengthening the dose regimen (twice daily for 5 days) and, to a lesser extent, intensifying the frequency of dosing (3 times daily for 3 days) would be more efficacious than using higher individual doses in the current standard treatment regimen (twice daily for 3 days). The model was developed using venous plasma data from patients receiving intact tablets with fat, and evaluations of alternative dosing regimens were consequently only representative for venous plasma after administration of intact tablets with fat. The absence of artemether-dihydroartemisinin data limited the prediction of parasite killing rates and recrudescent infections. Thus, the suggested optimised dosing schedule was based on the pharmacokinetic endpoint of lumefantrine plasma exposure at day 7.ConclusionsOur findings suggest that revised AL dosing regimens for young children and pregnant women would improve drug exposure but would require longer or more complex schedules. These dosing regimens should be evaluated in prospective clinical studies to determine whether they would improve cure rates, demonstrate adequate safety, and thereby prolong the useful therapeutic life of this valuable antimalarial treatment.

Resistance screening and trend analysis of imported falciparum malaria in NSW, Australia (2010 to 2016).

BackgroundThe World Health Organization currently recommends artemisinin (along with a partner drug) as the global frontline treatment for Plasmodium falciparum malaria. Artemisinin resistant P. falciparum are now found throughout the greater Mekong subregion of South East Asia. Several polymorphisms in the parasite’s kelch gene have been demonstrated to confer artemisinin resistance. While genotypes within the greater Mekong subregion are thoroughly examined in the literature, P. falciparum populations within several areas that do not (yet) have endemic resistance are underrepresented.ResultsThis investigation characterised the Pfkelch13 propeller domains from 153 blood samples of 140 imported cases of P. falciparum malaria in New South Wales from 2010 to 2016. A low level of propeller domain diversity was observed, including the C580Y coding mutation most strongly associated with artemisinin resistance in South East Asia. The resistance genotype was found in a sample originating in Papua New Guinea, where this mutation, or artemisinin treatment failure, have not been previously reported. Sequencing a panel of geographically informative polymorphisms within the organellar genomes identified the C580Y parasite as having Oceanic origins. Patient data analysis revealed that New South Wales, Australia, P. falciparum malaria cases often originated from regions with limited drug resistance screening.ConclusionsThe C580Y finding from outside of the greater Mekong subregion supports the consensus to upscale molecular surveillance of artemisinin resistance outside of South East Asia. The genetic screening results identify a risk of importing resistant falciparum malaria to Australia, supporting an ongoing surveillance protocol to pre-empt treatment failure and contribute to global data gathering.

Epidemic situation and diagnosis and treatment of severe falciparum malaria in Nantong City

To retrospectively analyze the epidemic situation and diagnosis and treatment of severe falciparum malaria in Nantong City, summarize the causes of severe falciparum malaria, and evaluate the effect of diagnosis and treatment, so as to provide the evidence for formulating the practical treatment measures for this disease. All the data of falciparum malaria cases in Nantong City from 2009 to 2016 were collected and analyzed for the onset time, diagnosis process and treatment of the disease. A total of 359 malaria cases, including 289 falciparum malaria cases, were reported in Nantong City from 2009 to 2016, including 26 severe falciparum malaria cases. All the severe falciparum malaria cases were imported from Africa, including 57.70% of cases (15/26) from Angola. All of them were male labor exporting personnel. The incidence of malaria was not obviously seasonal. The average time from onset to definite diagnosis was 5.2 days, and 11 cases were diagnosed 5 days after the onset. All the 26 cases were cured by anti-malaria treatment and symptomatic treatment, and there was no death. Severe falciparum malaria seriously harm the people's health and its clinical manifestations are complicated. Therefore, the training of medical staff and health education in residents, especially in labor exporting personnel, should be further strengthened.

Drugs in Development for Malaria.

The last two decades have seen a surge in antimalarial drug development with product development partnerships taking a leading role. Resistance of Plasmodium falciparum to the artemisinin derivatives, piperaquine and mefloquine in Southeast Asia means new antimalarials are needed with some urgency. There are at least 13 agents in clinical development. Most of these are blood schizonticides for the treatment of uncomplicated falciparum malaria, under evaluation either singly or as part of two-drug combinations. Leading candidates progressing through the pipeline are artefenomel–ferroquine and lumefantrine-KAF156, both in Phase 2b. Treatment of severe malaria continues to rely on two parenteral drugs with ancient forebears: artesunate and quinine, with sevuparin being evaluated as an adjuvant therapy. Tafenoquine is under review by stringent regulatory authorities for approval as a single-dose treatment for Plasmodium vivax relapse prevention. This represents an advance over standard 14-day primaquine regimens; however, the risk of acute haemolytic anaemia in patients with glucose-6-phosphate dehydrogenase deficiency remains. For disease prevention, several of the newer agents show potential but are unlikely to be recommended for use in the main target groups of pregnant women and young children for some years. Latest predictions are that the malaria burden will continue to be high in the coming decades. This fact, coupled with the repeated loss of antimalarials to resistance, indicates that new antimalarials will be needed for years to come. Failure of the artemisinin-based combinations in Southeast Asia has stimulated a reappraisal of current approaches to combination therapy for malaria with incorporation of three or more drugs in a single treatment under consideration.

Pyronaridine\u2013artesunate and artemether\u2013lumefantrine for the treatment of uncomplicated Plasmodium falciparum malaria in Kenyan children: a randomized controlled non-inferiority trial

BackgroundPyronaridine–artesunate is a novel artemisinin-based combination therapy. The efficacy and safety of pyronaridine–artesunate were compared with artemether–lumefantrine for the treatment of uncomplicated Plasmodium falciparum malaria in children.MethodsThis phase III open-label randomized controlled non-inferiority trial was conducted in Western Kenya. Children aged 6 months to ≤ 12 years with a bodyweight > 5 kg and microscopically confirmed P. falciparum malaria were randomly assigned in a 1:1 ratio to orally receive pyronaridine–artesunate or artemether–lumefantrine, dosed according to bodyweight, for 3 days.ResultsOf 197 participants, 101 received pyronaridine–artesunate and 96 received artemether–lumefantrine. The day-28 adequate clinical and parasitological response in the per-protocol population, PCR-corrected for reinfections, was 98.9% (93/94, 95% CI 94.2–99.8) for pyronaridine–artesunate and 96.4% (81/84, 95% CI 90.0–98.8) for artemether–lumefantrine. Pyronaridine–artesunate was found to be non-inferior to artemether–lumefantrine: the treatment difference was 2.5% (95% CI − 2.8 to 9.0). Adverse events occurred in 41.6% (42/101) and 34.4% (33/96) of patients in the pyronaridine–artesunate group and the artemether–lumefantrine group, respectively. No participants were found to have alanine or aspartate aminotransferase levels > 3 times the upper limit of normal.ConclusionsPyronaridine–artesunate was well tolerated, efficacious and non-inferior to artemether–lumefantrine for the treatment of uncomplicated P. falciparum malaria in Kenyan children. Results are in line with previous reports and inclusion of pyronaridine–artesunate in paediatric malaria treatment programmes should be considered.This study is registered at clinicaltrials.gov under NCT02411994. Registration date: 8 April 2015. https://clinicaltrials.gov/ct2/show/NCT02411994?term=pyronaridine–artesunate&cond=Malaria&cntry=KE&rank=1

Efficacy and safety of artemether\u2013lumefantrine, artesunate\u2013amodiaquine, and dihydroartemisinin\u2013piperaquine for the treatment of uncomplicated Plasmodium falciparum malaria in three provinces in Angola, 2017

BackgroundThe Angolan government recommends three artemisinin-based combinations for the treatment of uncomplicated Plasmodium falciparum malaria: artemether–lumefantrine (AL), artesunate–amodiaquine (ASAQ), and dihydroartemisinin–piperaquine (DP). Due to the threat of emerging anti-malarial drug resistance, it is important to periodically monitor the efficacy of artemisinin-based combination therapy (ACT). This study evaluated these medications’ therapeutic efficacy in Benguela, Lunda Sul, and Zaire Provinces.MethodsEnrollment occurred between March and July 2017. Study participants were children with P. falciparum monoinfection from each provincial capital. Participants received a 3-day course of a quality-assured artemisinin-based combination and were monitored for 28 (AL and ASAQ arms) or 42 days (DP arm). Each ACT was assessed in two provinces. The primary study endpoints were: (1) follow-up without complications and (2) failure to respond to treatment or development of recurrent P. falciparum infection. Parasites from each patient experiencing recurrent infection were genotyped to differentiate new infection from recrudescence of persistent parasitaemia. These parasites were also analysed for molecular markers associated with ACT resistance.ResultsOf 608 children enrolled in the study, 540 (89%) reached a primary study endpoint. Parasitaemia was cleared within 3 days of medication administration in all participants, and no early treatment failures were observed. After exclusion of reinfections, the corrected efficacy of AL was 96% (91–100%, 95% confidence interval) in Zaire and 97% (93–100%) in Lunda Sul. The corrected efficacy of ASAQ was 100% (97–100%) in Benguela and 93% (88–99%) in Zaire. The corrected efficacy of DP was 100% (96–100%) in Benguela and 100% in Lunda Sul. No mutations associated with artemisinin resistance were identified in the pfk13 gene in the 38 cases of recurrent P. falciparum infection. All 33 treatment failures in the AL and ASAQ arms carried pfmdr1 or pfcrt mutations associated with lumefantrine and amodiaquine resistance, respectively, on day of failure.ConclusionsAL, ASAQ, and DP continue to be efficacious against P. falciparum malaria in these provinces of Angola. Rapid parasite clearance and the absence of genetic evidence of artemisinin resistance are consistent with full susceptibility to artemisinin derivatives. Periodic monitoring of in vivo drug efficacy remains a priority routine activity for Angola.

Emergence and Spread of kelch13 Mutations Associated with Artemisinin Resistance in Plasmodium falciparum Parasites in 12 Thai Provinces from 2007 to 2016.

Artemisinin-based combination therapy (ACT) is the most effective and widely used treatment for uncomplicated Plasmodium falciparum malaria and is a cornerstone for malaria control and prevention globally. Resistance to artemisinin derivatives has been confirmed in the Greater Mekong Subregion (GMS) and manifests as slow parasite clearance in patients and reduced ring stage susceptibility to artemisinins in survival assays. The P. falciparumkelch13 gene mutations associated with artemisinin-resistant parasites are now widespread in the GMS. We genotyped 277 samples collected during an observational study from 2012 to 2016 from eight provinces in Thailand to identify P. falciparum kelch13 mutations. The results were combined with previously reported genotyping results from Thailand to construct a map illustrating the evolution of P. falciparum kelch13 mutations from 2007 to 2016 in that country. Different mutant alleles were found in strains with different geographical origins. The artemisinin resistance-conferring Y493H and R539T mutations were detected mainly in eastern Thailand (bordering Cambodia), while P574L was found only in western Thailand and R561H only in northwestern Thailand. The C580Y mutation was found across the entire country and was nearing fixation along the Thai-Cambodia border. Overall, the prevalence of artemisinin resistance mutations increased over the last 10 years across Thailand, especially along the Thai-Cambodia border. Molecular surveillance and therapeutic efficacy monitoring should be intensified in the region to further assess the extent and spread of artemisinin resistance.

Chloroquine diphosphate bearing dextran nanoparticles augmented drug delivery and overwhelmed drug resistance in Plasmodium falciparum parasites

Chloroquine diphosphate (CHQ) is primarily used for the treatment of Plasmodium falciparum malaria at the dose of 500mg orally or 10mg/kg parenterally. However, point mutations in Plasmodiumfalciparum chloroquine resistance transporter (PfCRT) protein and Plasmodium falciparum multidrug resistance protein 1 (Pfmdr1) localized in digestive vacuole membrane, are responsible for CHQ resistance. Therefore, in present investigation, dextran nanoparticles bearing chloroquine diphosphate (CHQ-DEX-NPs) were formulated by solvent diffusion method of size below 70nm with zeta-potential of −20.1±3.2mV. FT-IR, DSC and PXRD techniques confirmed the successful loading of drug in nanomatrix system with amorphous attributes. In vitro drug release analysis indicated the Higuchi pattern with diffusion controlled drug release. The IC50 of CHQ-DEX-NPs in sensitive (3D7) and resistant (RKL9) Plasmodium falciparum strains was estimated to be 0.031-μg/ml and 0.13-μg/ml significantly lower than 0.059-μg/ml and 0.36-μg/ml of CHQ. The augmented therapeutic efficacy of CHQ-DEX-NPs may be credited to deposition of tailored nanoparticles in food vacuoles of malaria parasites owing to the affinity of parasite towards DEX that consequently lower the drug resistance and improved the therapeutic index. In conclusion, CHQ-DEX-NPs must be evaluated under a set of stringent in vivo parameters to establish its therapeutic efficacy in preclinical model.

Efficacy and safety of artemisinin-based combination therapy for uncomplicated Plasmodium falciparum malaria in Sudan: a systematic review and meta-analysis

BackgroundMalaria is a major public health problem in endemic countries including Sudan, where about 75% of populations are at risk. Due to widespread of chloroquine-resistant strains of Plasmodium falciparum, artemisinin-based combination therapy (ACT) is currently treatment of choice for malaria in the vast majority of malaria-endemic countries. This systematic review and meta-analysis is performed to obtain an overall stronger evidence of the outcomes of ACT in the treatment of uncomplicated falciparum malaria from the existing literature in Sudan.MethodsThe preferred reporting items for systematic review and meta-analysis statement were used to select studies to be included in this review. A computerized systematic strategy was adopted to search articles from PubMed, Google Scholar and Science Direct databases. Unpublished materials were also included. Open Meta-Analyst software was used to perform the meta-analysis. Random effects model was used to combine the included studies and the heterogeneity of studies was assessed using Cochrane Q and I2 (χ2 = 73.05, df (19), P < 0.001 and I2 = 73.99).ResultsTwenty studies fulfilled the inclusion criteria (ACT in the treatment of uncomplicated falciparum malaria) and were included in the final analysis with a total number of 4070 participants. Malaria treatment outcome was assessed using World Health Organization guidelines. Adequate clinical and parasitological response was used to assess treatment success at the 28th day. Treatment success of all combined studies was 98% [(95% CI 97.2–98.8%), P < 0.001]. Treatment success was higher in malaria patients treated with artemether + lumefantrine (AL) than patients treated with artesunate + sulfadoxine–pyrimethamine (AS + SP) (98.9% (95% CI 98.4–99.4%) vs 97.1% (95% CI 95.5–98.6%), P < 0.001). Eleven studies reported adverse drug reactions (ADRs) to ACT (184 participants out of 3957 (4.65%). The ADRs were mild and resolved spontaneously. There was no severe ADRs or deaths.ConclusionBased on this review, the overall malaria treatment success was high (98%). AL regimen showed higher efficacy compared to AS + SP. The overall regimens were associated with mild low rates ADRs.