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Malaria is a leading cause of maternal and child mortality in urban Nigeria. Intermittent preventive treatment with sulfadoxine-pyrimethamine (IPTp-SP) during pregnancy can prevent malaria but uptake is suboptimal. This cross-sectional study analyzed secondary data on 1159 urban Nigerian women from the 2015 Malaria Indicator Survey using descriptive statistics and logistic regression. The primary outcome was optimal IPTp-SP uptake (≥ 3 doses). 67% of women took any SP during pregnancy but only 39% took ≥ 3 IPTp-SP doses as recommended. Region and wealth index significantly predicted optimal IPTp-SP uptake while education did not. Women from lower-income regions in the urban areas were less likely to receive optimal IPTp-SP. Strategies to increase IPTp-SP uptake in urban Nigeria should target low-income regions and women of lower socioeconomic status. Logistic regression identified actionable factors for improving antenatal malaria prevention. Optimal IPTp-SP uptake remains suboptimal across urban Nigeria, threatening maternal and child health., (© 2024. The Author(s).)

Background: Malaria is the leading cause of hospitalizations and death in Uganda, particularly in children under the age of five. Studies have shown that adherence to the World Health Organization (WHO) guidelines for the management of severe malaria reduces mortality in hospitalized children. This study aimed to determine the impact of targeted interventions on adherence to the WHO severe malaria treatment guidelines in children at a Ugandan hospital as part of a quality improvement initiative., Methods: Interventions included workflow changes, such as obtaining patient blood samples for diagnostic testing by the admitting healthcare provider as well as utilizing patient caregivers to assist nursing staff in timing medications. An additional intervention was the use of an admission checklist sticker. The post-intervention sample was compared to the baseline assessment. The primary outcome was the proportion of patients receiving care consistent with all aspects of the WHO guidelines. Secondary outcomes included the proportion of patients receiving malaria diagnostic testing, those receiving at least 3 doses of artesunate, the timely administration of artesunate, and adherence to other guideline components. Statistical analyses were conducted using GraphPad PRISM 9.0. Comparisons between groups were analysed using Chi-square or Fisher's exact test for categorical variables and Mann-Whitney test for continuous variables., Results: The post-intervention group included 230 patients with a median age of 5 years [4-8], and 58% of patients were male. Adherence to all aspects of the WHO guidelines was achieved in 10% of patients in the post-intervention group compared to 3% of patients in the baseline (P = 0.007). Appropriate malaria diagnostic testing was performed in 85% of patients post-intervention compared to 66% of patients in the baseline (P < 0.0001). Patients in the post-intervention group were more likely to receive the minimum 3 doses of artesunate (86%) than in the baseline (74%) (P = 0.008). Patients in the post-intervention group were more likely to receive artesunate doses on time than in the baseline (dose 2 P = 0.02, dose 3 P = 0.003)., Conclusions: Targeted, low-cost interventions led to improvement in adherence to severe malaria treatment guidelines. The most notable changes were in malaria diagnostic testing and antimalarial administration., (© 2024. The Author(s).)

Background: The Republic of Guinea, where malaria represents the leading cause of morbidity and mortality among children, the seasonal malaria chemoprevention (SMC) is deployed only in areas with very seasonal modes of transmission. It should target children at the highest risk of serious illness. The objective of the study was to prevent uncomplicated and serious cases of malaria in the target population. This study aimed to analyse the monthly trends in malaria-related morbidity among children under the age of 5 in Guinea., Methods: This was a quasi-experimental study with routine data from the National Health Information System (SNIS). The two districts Mamou (the SMC intervention site) and Kindia (the control site) were selected to compare the monthly trends in malaria cases among children under the age of 5, from July to October, covering the years from 2015 to 2020. The statistical analysis used interrupted time series to estimate the effects of the SMC., Results: The SMC programme contributed to a significant average reduction in the number of malaria cases of 225 cases per month in the intervention district (95% CI - 362 to - 88; p = 0.002), compared to the control district. However, the study also revealed that the effect of SMC varied between cycles, presenting different monthly malaria cases., Conclusion: The SMC contributed to a significant reduction in malaria cases among children under the age of 5 in the health district of Mamou from 2018 to 2020. However, this reduction varied by monthly SMC cycle. This study suggests extending the SMC in other areas with high perennial seasonal transmission respecting the World Health Organization SMC eligibility criteria, as a strategy in the dynamic of reducing malaria cases in children under the age of 5 in Guinea., (© 2024. The Author(s).)

Background: Seasonal malaria chemoprevention using sulfadoxine-pyrimethamine plus amodiaquine (sulfadoxine-pyrimethamine plus amodiaquine on Day 1 and amodiaquine on both Day 2 and Day 3) is delivered to children aged 3-59 months in areas of highly season malaria transmission. While the overall population-level impact of seasonal malaria chemoprevention on malaria control has been documented in various countries and time periods, there is no clear evidence regarding seasonal malaria chemoprevention impact based on the number of medicine doses children receive in one cycle in routine programmatic conditions., Methods: Data were extracted from Nigeria's routinely collected seasonal malaria chemoprevention end-of-round coverage surveys (2021, 2022). We matched seasonal malaria chemoprevention-targeted children who received specific numbers of seasonal malaria chemoprevention medicines with those who did not receive any doses of seasonal malaria chemoprevention medicines (non-sulfadoxine-pyrimethamine plus amodiaquine) using multiple sets of propensity score matches. We performed multilevel logistic regression for each matched group to evaluate the association between the number of doses of seasonal malaria chemoprevention medicines and monthly confirmed malaria cases (caregiver-reported malaria infection diagnosed by rapid diagnostic test at a health facility following the penultimate cycle of seasonal malaria chemoprevention)., Results: Among 21,621 SMC-targeted children, 9.7% received non-sulfadoxine-pyrimethamine plus amodiaquine, 0.5% received only Day 1 sulfadoxine-pyrimethamine plus amodiaquine, 1.0% received Day 1 sulfadoxine-pyrimethamine plus amodiaquine and either Day 2 amodiaquine or Day 3 amodiaquine (sulfadoxine-pyrimethamine plus amodiaquine + amodiaquine), and 88.8% received Day 1 sulfadoxine-pyrimethamine plus amodiaquine and both Day 2 and Day 3 amodiaquine (sulfadoxine-pyrimethamine plus amodiaquine + amodiaquine + amodiaquine). Children receiving only Day 1 sulfadoxine-pyrimethamine plus amodiaquine did not have significant lower odds of rapid diagnostic tests-confirmed malaria than those receiving non-sulfadoxine-pyrimethamine plus amodiaquine (OR 0.77, 0.42-1.42). However, children receiving sulfadoxine-pyrimethamine plus amodiaquine + amodiaquine had significantly lower odds of rapid diagnostic tests-confirmed malaria than those receiving non-sulfadoxine-pyrimethamine plus amodiaquine (OR 0.42, 95% CI 0.28-0.63). Similarly, children receiving sulfadoxine-pyrimethamine plus amodiaquine + amodiaquine + amodiaquine also had significantly lower odds of rapid diagnostic test-confirmed malaria than those receiving non-sulfadoxine-pyrimethamine plus amodiaquine (OR 0.54, 95% CI 0.47-0.62)., Conclusion: Adherence to at least one daily dose of amodiaquine administration following receipt of Day 1 sulfadoxine-pyrimethamine plus amodiaquine by eligible children is crucial to ensure the effectiveness of seasonal malaria chemoprevention. This demonstrates the importance of enhancing caregiver awareness regarding the importance of amodiaquine and identifying barriers toward amodiaquine administration at the community level., (© 2024 The Author(s). Tropical Medicine & International Health published by John Wiley & Sons Ltd.)

Infection with Plasmodium falciparum is often deadly when it results in cerebral malaria, which is associated with neuropathology described as an overwhelming inflammatory response and mechanical obstruction of cerebral microvascular. PI3Kγ is a critical component of intracellular signal transduction and plays a central role in regulating cell chemotaxis, migration, and activation. The purpose of this study was to examine the relationship between inhibiting the PI3Kγ pathway and the outcome of experimental cerebral malaria (ECM) in C57BL/6J mice infected with the mouse malaria parasite, Plasmodium berghei ANKA. We observed that oral administration of the PI3Kγ inhibitor IPI549 after infection completely protected mice from ECM. IPI549 treatment significantly dampened the magnitude of inflammatory responses, with reduced production of pro-inflammatory factors, decreased T cell activation, and altered differentiation of antigen-presenting cells. IPI549 treatment protected the infected mice from neuropathology, as assessed by an observed reduction of pathogenic T cells in the brain. Treating the infected mice with IPI549 three days after parasite inoculation improved the murine blood brain barrier (BBB) integrity and helped the mice pass the onset of ECM. Together, these data indicate that oral administration of the PI3Kγ inhibitor IPI549 has a suppressive role in host inflammation and alleviates cerebral pathology, which supports IPI549 as a new malaria treatment option with potential therapeutic implications for cerebral malaria., Competing Interests: Declaration of competing interest The research was conducted without commercial or financial relationships for any of the authors. Contributions from all authors were reviewed and approved before the article was submitted. The authors declare that they have no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: The WHO 2016 antenatal care (ANC) policy recommends at least eight antenatal contacts during pregnancy. This study assessed ANC8 uptake following policy implementation and explored the relationship between ANC attendance and intermittent preventive treatment in pregnancy (IPTp) coverage in sub-Saharan Africa following the rollout of the World Health Organization (WHO) 2016 ANC policy, specifically, to assess differences in IPTp uptake between women attending eight versus four ANC contacts., Methods: A secondary analysis of data from 20 sub-Saharan African countries with available Demographic Health and Malaria Indicator surveys from 2018 to 2023 was performed. The key variables were the number of ANC contacts and IPTp doses received during a participant's last completed pregnancy in the past two years. Pooled crude and multivariable logistic regression models were used to explore factors associated with attendance of at least four or eight ANC contacts as well as receipt of at least three doses of IPTp during pregnancy., Results: Overall, only a small proportion of women (median = 3.9%) completed eight or more ANC contacts (ANC8 +). Factors significantly associated with increased odds of ANC8 + included early ANC attendance (AOR: 4.61: 95% CI 4.30-4.95), literacy (AOR: 1.20; 95% CI 1.11-1.29), and higher wealth quintile (AOR: 3.03; 95% CI 2.67-3.44). The pooled estimate across all countries showed a very slight increase in the odds of IPTp3 + among women with eight (AOR: 1.06; 95% CI 1.00-1.12) compared to those with four contacts. In all but two countries, having eight instead of four ANC contacts did not confer significantly greater odds of receiving three or more doses of IPTp (IPTp3 +), except in Ghana (AOR: 1.67; 95% CI 1.38-2.04) and Liberia (AOR: 1.43; 95% CI 1.18-1.72)., Conclusion: Eight years after the WHO ANC policy recommendation, all countries still had sub-optimal ANC8 + coverage rates. This paper is a call to action to actualize the vision of the WHO and the global malaria community of a malaria free world. Policies to improve ANC and IPTp coverage should be operationalized with clear actionable guidance and local ownership. Study findings can be used to inform multi-level policy, programmatic, and research recommendations to optimize ANC attendance and malaria in pregnancy prevention, thus improving maternal and child health outcomes, including the reduction of malaria in pregnancy., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Background: Recommended since 2012 by the World Health Organization (WHO), seasonal malaria chemoprevention (SMC) is a community-based intervention to prevent malaria in children in African regions where malaria transmission follows a seasonal pattern. Following the publication of consolidated WHO guidelines for malaria, SMC is expected to reach more children in new geographies in future years. Though SMC has been shown to reduce malaria-related morbidity and mortality, there is potential for quality improvement of the intervention implementation. Assisted by ten quality standards from a framework developed by Malaria Consortium, this paper aims to better understand the quality of SMC implementation and identify potential barriers to quality delivery of SMC., Methods: A qualitative thematic analysis on data collected after the annual SMC rounds implemented in Burkina Faso and Chad in 2019 was conducted. Sixteen focus group discussions conducted with caregivers and community distributors were analysed. Three selected quality standards for SMC delivery; planning and enumeration; community engagement; and administration of SMC medicines provided overarching quality themes under which subthemes were identified., Results: Eight subthemes relating to the three quality standards were identified. Although SMC was well accepted by communities in both settings, common barriers to the quality delivery of SMC were identified including difficulty ensuring adherence to the SMC administration protocol; difficulties reaching mobile populations; concerns around adverse drug reactions; rumours, and concerns about SMC safety; and community distributors' working conditions. Context-specific barriers included: the suboptimal timeliness of the SMC round in Burkina Faso, and the lack of involvement of female caregivers in mobilization activities in Chad., Conclusion: In the context of increased adoption of SMC, this paper provides relevant insights and recommendations for the improved implementation of SMC programmes. These include the integration of strategies addressing communities' concerns around adverse drug reactions, gender-specific mobilization strategies, and attention to community distributors' working conditions. It also highlights the importance and utility of further, robust research on the quality of SMC delivery., (© 2024. The Author(s).)

Background: To interrupt residual malaria transmission and achieve successful elimination of Plasmodium falciparum in low-transmission settings, the World Health Organization (WHO) recommends the administration of a single dose of 0.25 mg/kg (or 15 mg/kg for adults) primaquine (PQ) combined with artemisinin-based combination therapy (ACT), without glucose-6-phosphate dehydrogenase (G6PD) testing. However, due to the risk of haemolysis in patients with G6PD deficiency (G6PDd), PQ use is uncommon. Thus, this study aimed to assess the safety of a single low dose of PQ administered to patients with G6PD deficiency., Methods: An observational cohort study was conducted with patients treated for uncomplicated P. falciparum malaria with either single-dose PQ (0.25 mg/kg) (SLD PQ) + ACT or ACT alone. Microscopy-confirmed uncomplicated P. falciparum malaria patients visiting public health facilities in Arjo Didessa, Southwest Ethiopia, were enrolled in the study from September 2019 to November 2022. Patients with uncomplicated P. falciparum malaria were followed up for 28 days through clinical and laboratory diagnosis, such as measurements of G6PD levels and haemoglobin (Hb) concentrations. G6PD levels were measured by a quantiative CareSTART™ POCT S1 biosensor machine. Patient interviews were also conducted, and the type and frequency of clinical complaints were recorded. Hb data were taken on days (D) 7, 14, 21, and 28 following treatment with SLD-PQ + ACT or ACT alone., Results: A total of 249 patients with uncomplicated P. falciparum malaria were enrolled in this study. Of these, 83 (33.3%) patients received ACT alone, and 166 (66.7%) received ACT combined with SLD-PQ treatment. The median age of the patients was 20 (IQR 28-15) years. G6PD deficiency was found in 17 (6.8%) patients, 14 males and 3 females. There were 6 (7.2%) and 11 (6.6%) phenotypic G6PD-deficient patients in the ACT alone and ACT + SLD-PQ arms, respectively. The mean Hb levels in patients treated with ACT + SLD-PQ were reduced by an average of 0.45 g/dl (95% CI = 0.39 to 0.52) in the posttreatment phase (D7) compared to a reduction of 0.30 g/dl (95% CI = 0.14 to - 0.47) in patients treated with ACT alone (P = 0.157). A greater mean Hb reduction was observed on day 7 in the G6PDd ACT + SLD-PQ group (- 0.60 g/dL) than in the G6PDd ACT alone group (- 0.48 g/dL); however, there was no statistically significant difference (P = 0.465). Overall, D14 losses were 0.10 g/dl (95% CI = - 0.00 to 0.20) and 0.05 g/dl (95% CI = - 0.123 to 0.22) in patients with and without SLD-PQ, respectively (P = 0.412)., Conclusions: This study's findings indicate that using SLD-PQ in combination with ACT is safe for uncomplicated P. falciparum malaria regardless of the patient's G6PD status in Ethiopian settings. Caution should be taken in extrapolating this finding in other settings with diverse G6DP phenotypes., (© 2024. The Author(s).)

Background: Dihydroartemisinin-piperaquine (DHP) recently showed superior effectiveness over sulfadoxine-pyrimethamine for malaria intermittent preventive treatment in pregnancy (IPTp). We investigated day 7 piperaquine pharmacokinetics and its therapeutic efficacy in preventing malaria during pregnancy., Methods: Malaria-free (mRDT) pregnant women (n = 400) who received monthly IPTp-DHP were enrolled and followed till delivery. Day 7 Plasma piperaquine concentrations were determined after each IPTp dose using UPLC/MS/MS. IPTp outcomes (symptomatic malaria and parasitemia during pregnancy, placental malaria, and maternal malaria at delivery) were monitored. Linear mixed model and Cox regression were used to assess predictors of day 7 piperaquine concentration and treatment outcome, respectively., Results: The incidences of symptomatic malaria and parasitemia during pregnancy per 100 person-year at risk were 2 and 33, respectively. The prevalence of histopathologically confirmed placental malaria and maternal malaria at delivery were 3% and 9.8%, respectively. Repeated monthly IPTp-DHP resulted in significantly increased day 7 plasma piperaquine concentration (p < 0.001). Following the 1st, 2nd, and 3rd monthly IPTp-DHP doses, the proportions of women with day 7 piperaquine concentration below the therapeutic threshold (< 30 ng/mL) were 6.1%, 4.1% and 3.6%, respectively. Factors such as maternal age, body weight and trimester were not significant predictors of day 7 piperaquine concentration. However, having a low day 7 piperaquine plasma concentration (< 30 ng/mL) was significantly associated with a higher risk of parasitemia during pregnancy (p = 0.004)., Conclusion: Lower day 7 piperaquine plasma concentration is a risk factor for parasitemia during pregnancy. Single plasma sampling at day 7 can be used to monitor piperaquine effectiveness during IPTp-DHP., Trial Registration: Registered 09/12/2016, PACTR201612001901313., (© 2024. The Author(s).)

Background: Plasmodium vivax malaria is still an important public health problem in Ethiopia. Unlike Plasmodium falciparum, P. vivax has a dormant liver stage (hypnozoite) that can be a risk of recurrent vivax malaria unless treated by radical cure with primaquine. Drug resistance to chloroquine is threatening malaria control and elimination efforts. This study assessed the therapeutic efficacy and safety of chloroquine plus 14 days of primaquine on P. vivax infection based on parasitological, clinical, and haematological parameters., Methods: A single-arm in vivo prospective therapeutic efficacy study was conducted to assess the clinical and parasitological response to the first-line treatment of P. vivax in Ethiopia, chloroquine plus 14 days low dose of (0.25 mg/kg/day) primaquine between December 2022 and March 2023 at Hamusit Health Centre using the standard World Health Organization (WHO) protocol. A total of 100 study participants with P. vivax mono-infection who were over 6 months old were enrolled and monitored for adequate clinical and parasitological responses for 42 days. The WHO double-entry Excel sheet and SPSS v.25 software were used for Kaplan-Meier survival analysis, and a paired t-test was used for analysis of haemoglobin improvements between follow up days., Results: A total of 100 patients were enrolled among those, 96% cases were rural residents, 93% had previous malaria exposure, and predominant age group was 5-15 years (61%). 92.6% (95% CI 85.1-96.4%) of enrolled patients were adequate clinical and parasitological response, and 7.4% (95% CI 3.6-14.9%) recurrences were observed among treated patients. The fever and parasite clearance rate on day 3 were 98% and 94%, respectively. The baseline haemoglobin levels improved significantly compared to those days 14 and 42 (p < 0.001). No serious adverse event was observed during the study period., Conclusions: In this study, co-administration of chloroquine with primaquine was efficacious and well-tolerated with fast resolution of fever and high parasites clearance rate. However, the 7.4% failure is reported is alarming that warrant further monitoring of the therapeutic efficacy study of P. vivax., (© 2024. The Author(s).)

Background: Intermittent preventive treatment in pregnancy with sulfadoxine-pyrimethamine (IPTp-SP) reduces malaria-attributable adverse pregnancy outcomes and may also prevent low birth weight (< 2,500 g) through mechanisms independent of malaria. Malaria transmission in Papua New Guinea (PNG) is highly heterogeneous. The impact of IPTp-SP on adverse birth outcomes in settings with little or no malaria transmission, such as PNG's capital city Port Moresby, is unknown., Methods: A retrospective cohort study was conducted amongst HIV-negative women with a singleton pregnancy who delivered at Port Moresby General Hospital between 18 July and 21 August 2022. The impact of IPTp-SP doses on adverse birth outcomes and anaemia was assessed using logistic and linear regression models, as appropriate., Results: Of 1,140 eligible women amongst 1,228 consecutive births, 1,110 had a live birth with a documented birth weight. A total of 156 women (13.7%) did not receive any IPTp-SP, 347 women (30.4%) received one, 333 (29.2%) received two, and 304 (26.7%) received the recommended ≥ 3 doses of IPTp-SP. A total of 65 of 1,110 liveborn babies (5.9%) had low birth weight and there were 34 perinatal deaths (3.0%). Anaemia (haemoglobin < 100 g/L) was observed in 30.6% (243/793) of women, and 14 (1.2%) had clinical malaria in pregnancy. Compared to women receiving 0-1 dose of IPTp-SP, women receiving ≥ 2 doses had lower odds of LBW (adjusted odds ratio [aOR] 0.50; 95% confidence interval [CI] 0.26, 0.96), preterm birth (aOR 0.58; 95% CI 0.32, 1.04), perinatal death (aOR 0.49; 95% CI 0.18, 1.38), LBW/perinatal death (aOR 0.55; 95% CI 0.27, 1.12), and anaemia (OR 0.50; 95% CI 0.36, 0.69). Women who received 2 doses versus 0-1 had 45% lower odds of LBW (aOR 0.55, 95% CI 0.27, 1.10), and a 16% further (total 61%) reduction with ≥ 3 doses (aOR 0.39, 95% CI 0.14, 1.05). Birth weights for women who received 2 or ≥ 3 doses versus 0-1 were 81 g (95% CI -3, 166) higher, and 151 g (58, 246) higher, respectively., Conclusions: Provision of IPTp-SP in a low malaria-transmission setting in PNG appears to translate into substantial health benefits, in a dose-response manner, supporting the strengthening IPTp-SP uptake across all transmission settings in PNG., (© 2024. The Author(s).)

The urgent need for safe, efficacious, and accessible drug treatments to treat coronavirus disease 2019 (COVID-19) prompted a global effort to evaluate drug repurposing opportunities. Pyronaridine and amodiaquine are both components of approved antimalarials with in vitro activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In vitro activity does not always translate to clinical efficacy across a therapeutic dose range. This study applied available, verified, physiologically based pharmacokinetic (PBPK) models for pyronaridine, amodiaquine, and its active metabolite N-desethylamodiaquine (DEAQ) to predict drug concentrations in lung tissue relative to plasma or blood in the default healthy virtual population. Lung exposures were compared to published data across the reported range of in vitro EC 50 values against SARS-CoV-2. In the multicompartment permeability-limited PBPK model, the predicted total C max in lung mass for pyronaridine was 34.2 μM on Day 3, 30.5-fold greater than in blood (1.12 μM) and for amodiaquine was 0.530 μM, 8.83-fold greater than in plasma (0.060 μM). In the perfusion-limited PBPK model, the DEAQ predicted total C max on Day 3 in lung mass (30.2 μM) was 21.4-fold greater than for plasma (1.41 μM). Based on the available in vitro data, predicted drug concentrations in lung tissue for pyronaridine and DEAQ, but not amodiaquine, appeared sufficient to inhibit SARS-CoV-2 replication. Simulations indicated standard dosing regimens of pyronaridine-artesunate and artesunate-amodiaquine have potential to treat COVID-19. These findings informed repurposing strategies to select the most relevant compounds for clinical investigation in COVID-19. Clinical data for model verification may become available from ongoing clinical studies., (© 2024 The Author(s). Clinical and Translational Science published by Wiley Periodicals LLC on behalf of American Society for Clinical Pharmacology and Therapeutics.)

Antimalarials (AMs), particularly hydroxychloroquine (HCQ) and chloroquine (CQ), are the cornerstone of the treatment for both systemic lupus erythematosus (SLE) and cutaneous lupus erythematosus (CLE). HCQ and CQ are recommended as first-line oral agents in all CLE guidelines. Initially thought to have potential therapeutic effects against COVID-19, HCQ has drawn significant attention in recent years, highlighting concerns over its potential toxicity among patients and physicians. This review aims to consolidate current evidence on the efficacy of AMs in CLE. Our focus will be on optimizing therapeutic strategies, such as switching from HCQ to CQ, adding quinacrine to either HCQ or CQ, or adjusting HCQ dose based on blood concentration. Additionally, we will explore the potential for HCQ dose reduction or discontinuation in cases of CLE or SLE remission. Our review will focus on the existing evidence regarding adverse events linked to AM usage, with a specific emphasis on severe events and those of particular interest to dermatologists. Last, we will discuss the optimal HCQ dose and the balance between preventing CLE or SLE flares and minimizing toxicity., (© 2024 Japanese Dermatological Association.)

With the spread of artemisinin resistance throughout Southeast Asia and now in Africa, the antimalarial drug pyronaridine is likely to become an increasingly important component of new antimalarial drug regimens. However, the antimalarial activity of pyronaridine in humans has not been completely characterised. This volunteer infection study aimed to determine the pharmacokinetic/pharmacodynamic (PK/PD) relationship of pyronaridine in malaria naïve adults. Volunteers were inoculated with Plasmodium falciparum-infected erythrocytes on day 0 and administered different single oral doses of pyronaridine on day 8. Parasitaemia and concentrations of pyronaridine were measured and standard safety assessments performed. Curative artemether-lumefantrine therapy was administered if parasite regrowth occurred, or on day 47 ± 2. Outcomes were parasite clearance kinetics, PK and PK/PD parameters from modelling. Ten participants were inoculated and administered 360 mg (n = 4), 540 mg (n = 4) or 720 mg (n = 1) pyronaridine. One participant was withdrawn without receiving pyronaridine. The time to maximum pyronaridine concentration was 1-2 h, the elimination half-life was 8-9 d, and the parasite clearance half-life was approximately 5 h. Parasite regrowth occurred with 360 mg (4/4 participants) and 540 mg (2/4 participants). Key efficacy parameters including the minimum inhibitory concentration (5.5 ng/mL) and minimum parasiticidal concentration leading to 90% of maximum effect (MPC 90 : 8 ng/mL) were derived from the PK/PD model. Adverse events considered related to pyronaridine were predominantly mild to moderate gastrointestinal symptoms. There were no serious adverse events. Data obtained in this study will support the use of pyronaridine in new antimalarial combination therapies by informing partner drug selection and dosing considerations., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

The overarching premise of this investigation is that injectable, long-acting antimalarial medication would encourage adherence to a dosage regimen for populations at risk of contracting the disease. To advance support for this goal, we have developed oil-based formulations of ELQ-331 (a prodrug of ELQ-300) that perform as long-acting, injectable chemoprophylactics with drug loading as high as 160 mg/ml of ELQ-331. In a pharmacokinetic study performed with rats, a single intramuscular injection of 12.14 mg/kg maintained higher plasma levels than the previously established minimum fully protective plasma concentration (33.25 ng/ml) of ELQ-300 for more than 4 weeks. The formulations were well tolerated by the rats and the tested dose produced no adverse reactions. We believe that by extending the length of time between subsequent injections, these injectable oil-based solutions of ELQ-331 can offer a more accessible, low-cost option for long-acting disease prevention and reduced transmission in malaria-endemic regions and may also be of use to travelers., (Copyright © 2024. Published by Elsevier B.V.)

Background: A challenge in achieving the malaria-elimination target in the Greater Mekong Subregion, including Thailand, is the predominance of Plasmodium vivax malaria, which has shown extreme resilience to control measures., Objective: This proof-of-concept study aimed to provide evidence for implementing primaquine mass drug administration (pMDA) as a strategy for P. vivax elimination in low-endemicity settings., Methods: The study employed a mixed-methods trial to thoroughly evaluate the effectiveness, safety, acceptability, and community engagement of pMDA. The quantitative part was designed as a 2-period cluster-crossover randomized controlled trial. The intervention was pMDA augmented to the national prevention and control standards with directly observed treatment (DOT) by village health volunteers. The qualitative part employed in-depth interviews and brainstorming discussions. The study involved 7 clusters in 2 districts of 2 southern provinces in Thailand with persistently low P. vivax transmission. In the quantitative part, 5 cross-sectional blood surveys were conducted in both the pMDA and control groups before and 3 months after pMDA. The effectiveness of pMDA was determined by comparing the proportions of P. vivax infections per 1000 population between the 2 groups, with a multilevel zero-inflated negative binomial model adjusted for cluster and time as covariates and the interaction. The safety data comprised adverse events after drug administration. Thematic content analysis was used to assess the acceptability and engagement of stakeholders., Results: In the pre-pMDA period, the proportions of P. vivax infections in the pMDA (n=1536) and control (n=1577) groups were 13.0 (95% CI 8.2-20.4) and 12.0 (95% CI 7.5-19.1), respectively. At month 3 post-pMDA, these proportions in the pMDA (n=1430) and control (n=1420) groups were 8.4 (95% CI 4.6-15.1) and 5.6 (95% CI 2.6-11.5), respectively. No statistically significant differences were found between the groups. The number of malaria cases reduced in all clusters in both groups, and thus, the impact of pMDA was inconclusive. There were no major safety concerns. Acceptance among the study participants and public health care providers at local and national levels was high, and they believed that pMDA had boosted awareness in the community., Conclusions: pMDA was associated with high adherence, safety, and tolerability, but it may not significantly impact P. vivax transmission. As this was a proof-of-concept study, we decided not to scale up the intervention with larger clusters and samples. An alternative approach involving a targeted primaquine treatment strategy with primaquine and DOT is currently being implemented. We experienced success regarding effective health care workforces at point-of-care centers, effective collaborations in the community, and commitment from authorities at local and national levels. Our efforts boosted the acceptability of the malaria-elimination initiative. Community engagement is recommended to achieve elimination targets., Trial Registration: Thai Clinical Trials Registry TCTR20190806004; https://www.thaiclinicaltrials.org/show/TCTR20190806004., (©Jaranit Kaewkungwal, Wanlapa Roobsoong, Saranath Lawpoolsri, Wang Nguitragool, Suwich Thammapalo, Pathomporn Prikchoo, Amnat Khamsiriwatchara, Rungrawee Pawarana, Pawinee Jarujareet, Daniel M Parker, Piyarat Sripoorote, Mondha Kengganpanich, Chetta Ngamjarus, Jetsumon Sattabongkot, Liwang Cui. Originally published in JMIR Public Health and Surveillance (https://publichealth.jmir.org), 26.06.2024.)

Background: the mortality associated with severe malaria due to Plasmodiun falciparum remains high despite improvements in malaria management. Case prensentation: this case series aims to describe the efficacy and safety of the exchange transfusion combined with artesunate (ET-AS) regimen in severe P. falciparum malaria. Eight patients diagnosed with severe P. falciparum malaria were included. All patients underwent ET using the COBE Spectra system. The aimed for a post-exchange hematocrit of 30%. Half the estimated blood volume was removed and replaced using fresh frozen plasma. The regimen was well-tolerated without complications. The parasite clearance time ranged from 1 ~ 5 days. Five patients with cerebral malaria exhibited full improved consciousness within 3 days, while patient2 with hemolysis improved on day 2. Liver function improved within 1 ~ 6 days, and patient 1 and patient 6 showed improvements renal function on days 18 and 19, respectively. The length of intensive care unit stay range from 2 ~ 10 days, and all patients treated with ET-AS remained in the hospital for 3 ~ 19 days., Conclusions: these preliminary results suggest that ET-AS regimens are a safe and effective therapy for severe P. falciparum malaria and can benefit patients in clinical settings., (© 2024. The Author(s).)

Pulsatile drug delivery is hardly achieved by conventional gastro-retentive dosage forms. Artesunate as a typical anti-malaria medicine needs oral pulsatile release. Here, artesunate-loaded pulsatile-release multi-unit gastro-retentive tablets (APGTs) were prepared with a semi-solid extrusion three-dimensional (3D) printing method. An APGT was composed of three units: artesunate-loaded immediate and delayed release units and a block unit. The matrix of the immediate/delayed release units consisted of polyvinylpyrrolidone (PVP) K30 and croscarmellose sodium, which improved the rapid release of artesunate when contacting water. The block unit consisted of octadecanol, hydroxypropyl methyl cellulose K15M, PVP K30, and poloxamer F68. APGTs showed multi-phase release in simulated gastric liquids (SGLs). The first immediate release phase continued for 1 h followed by a long block phase for 7 h. The second rapid release phase was initiated when the eroded holes in the block unit extended to the inner delayed release unit, and this phase continued for about 14 h. Low-density APGTs could ensure their long-term floating in the stomach. Oral APGTs remained in the rabbit stomach for about 20 h. 3D printing provides a new strategy for the preparation of oral pulsatile-release tablets., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: With only one 15 mg primaquine tablet registered by a stringent regulatory authority and marketed, more quality-assured primaquine is needed to meet the demands of malaria elimination., Methods: A classic, two sequence, crossover study, with a 10-day wash out period, of 15 mg of IPCA-produced test primaquine tablets and 15 mg of Sanofi reference primaquine tablets was conducted. Healthy volunteers, aged 18-45 years, without glucose-6-phosphate dehydrogenase deficiency, a baseline haemoglobin ≥ 11 g/dL, creatinine clearance ≥ 70 mL/min/1.73 ms, and body mass index of 18.5-30 kg/m 2 were randomized to either test or reference primaquine, administered on an empty stomach with 240 mL of water. Plasma primaquine and carboxyprimaquine concentrations were measured at baseline, then 0.25, 0.5, 0.75, 1.0, 1.25, 1.5, 1.75, 2.0, 2.333, 2.667, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 8.0, 10.0, 12.0, 16.0, 24.0, 36.0, 48.0 and 72.0 h by liquid chromatography coupled to tandem mass spectrometry. Primaquine pharmacokinetic profiles were evaluated by non-compartmental analysis and bioequivalence concluded if the 90% confidence intervals (CI) of geometric mean (GM) ratios of test vs. reference formulation for the peak concentrations (C max ) and area under the drug concentration-time (AUC 0-t ) were within 80.00 to 125.00%., Results: 47 of 50 volunteers, median age 33 years, completed both dosing rounds and were included in the bioequivalence analysis. For primaquine, GM C max values for test and reference formulations were 62.12 vs. 59.63 ng/mL, resulting in a GM ratio (90% CI) of 104.17% (96.92-111.96%); the corresponding GM AUC 0-t values were 596.56 vs. 564.09 ngxh/mL, for a GM ratio of 105.76% (99.76-112.08%). Intra-subject coefficient of variation was 20.99% for C max and 16.83% for AUC 0-t . Median clearances and volumes of distribution were similar between the test and reference products: 24.6 vs. 25.2 L/h, 189.4 vs. 191.0 L, whilst the median half-lives were the same, 5.2 h., Conclusion: IPCA primaquine was bioequivalent to the Sanofi primaquine. This opens the door to prequalification, registration in malaria endemic countries, and programmatic use for malaria elimination. Trial registration The trial registration reference is ISRCTN 54640699., (© 2024. The Author(s).)

Background: Prevention of Plasmodium vivax malaria recurrence is essential for malaria elimination in Brazil. We evaluated the real-world effectiveness of an updated treatment algorithm for P vivax radical cure in the Brazilian Amazon., Methods: In this non-interventional observational study, we used retrospective data from the implementation of a P vivax treatment algorithm at 43 health facilities in Manaus and Porto Velho, Brazil. The treatment algorithm consisted of chloroquine (25 mg/kg over 3 days) and point-of-care quantitative glucose-6-phosphate dehydrogenase (G6PD) testing followed by single-dose tafenoquine 300 mg (G6PD normal, aged ≥16 years, not pregnant and not breastfeeding), 7-day primaquine 0·5 mg/kg per day (G6PD intermediate or normal, aged ≥6 months, not pregnant, and not breastfeeding or breastfeeding for >1 month), or primaquine 0·75 mg/kg per week for 8 weeks (G6PD deficient, aged ≥6 months, not pregnant, and not breastfeeding or breastfeeding for >1 month). P vivax recurrences were identified from probabilistic linkage of routine patient records from the Brazilian malaria epidemiological surveillance system. Recurrence-free effectiveness at day 90 and day 180 was estimated using Kaplan-Meier analysis and hazard ratios (HRs) by multivariate analysis. This clinical trial is registered with ClinicalTrials.gov, NCT05096702, and is completed., Findings: Records from Sept 9, 2021, to Aug 31, 2022, included 5554 patients with P vivax malaria. In all treated patients of any age and any G6PD status, recurrence-free effectiveness at day 180 was 75·8% (95% CI 74·0-77·6) with tafenoquine, 73·4% (71·9-75·0) with 7-day primaquine, and 82·1% (77·7-86·8) with weekly primaquine. In patients aged at least 16 years who were G6PD normal, recurrence-free effectiveness until day 90 was 88·6% (95% CI 87·2-89·9) in those who were treated with tafenoquine (n=2134) and 83·5% (79·8-87·4) in those treated with 7-day primaquine (n=370); after adjustment for confounding factors, the HR for recurrence following tafenoquine versus 7-day primaquine was 0·65 (95% CI 0·49-0·86; p=0·0031), with similar outcomes between the two treatments at day 180 (log-rank p=0·82). Over 180 days, median time to recurrence in patients aged at least 16 years who were G6PD normal was 92 days (IQR 76-120) in those treated with tafenoquine and 68 days (52-94) in those treated with 7-day primaquine., Interpretation: In this real-world setting, single-dose tafenoquine was more effective at preventing P vivax recurrence in patients aged at least 16 years who were G6PD normal compared with 7-day primaquine at day 90, while overall efficacy at 180 days was similar. The public health benefits of the P vivax radical cure treatment algorithm incorporating G6PD quantitative testing and tafenoquine support its implementation in Brazil and potentially across South America., Funding: Brazilian Ministry of Health, Municipal and State Health Secretariats; Fiocruz; Medicines for Malaria Venture; Bill & Melinda Gates Foundation; Newcrest Mining; and the UK Government., Translation: For the Portuguese translation of the abstract see Supplementary Materials section., Competing Interests: Declaration of interests SD, PGD, IB-F, and EJ are employees of Medicines for Malaria Venture. DBP declares grants from Butantan, PATH, and Janssen, payment for lectures or presentations from GSK, and support for attending meetings and travel from Janssen. All other authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Background: Community-based approaches might increase uptake of intermittent preventive treatment of malaria in pregnancy with sulfadoxine-pyrimethamine (IPTp-SP). We assessed the effects of community-based approaches on IPTp-SP and antenatal care coverage, and barriers and facilitators to implementation in sub-Saharan Africa., Methods: We did a systematic review, meta-analysis, meta-ethnography, and economic assessment. We searched the WHO International Clinical Trials Registry Platform, PubMed, the Malaria in Pregnancy Library database, Medline, Global Health and Global Health Archives, and the Cochrane Library for trials, mixed-methods, qualitative, and cost-effectiveness studies of community health worker promotion of antenatal care, IPTp-SP delivery, or both, with no language restrictions, published before March 21, 2024. Information on interventions, number of IPTp-SP doses, antenatal care visits, and barriers and facilitators were extracted. We did a meta-analysis (random effects) comparing effects on two or more or three or more IPTp-SP doses and one or more or four or more antenatal care visits. We followed Noblit and Hare's method of meta-ethnography to synthesise qualitative findings, using reciprocal translation and line-of-argument synthesis. We developed a theory for increased community IPTp-SP uptake. We also summarised cost and cost-effectiveness studies. This study is registered with PROSPERO, CRD42022364114., Findings: Of 4753 records screened, we included 23 (0·5%) reporting on 15 studies. Community health worker involvement was associated with an increase in two or more IPTp-SP doses (pooled risk ratio 1·48, [95% CI 1·24-1·75]; 12 sub-studies; I 2 94·7%) and three or more IPTp-SP doses (1·73 [1·19-2·50]; ten sub-studies, I 2 97·5%), with no decrease in four or more antenatal care visits (1·17 [1·00-1·36]; 13 sub-studies; I 2 90·3%). Cluster-randomised controlled trials showed a lower increase in coverage of three or more IPTp-SP doses (1·08 [1·00-1·16]; I 2 0·0%; six studies) compared with before-and-after studies (2·86 [1·29-6·33]; I 2 98·9%; four studies; subgroup analysis p=0·019). Barriers to community health worker delivery of IPTp-SP included women's fear of side-effects, lack of knowledge, lack of trust in community health workers, and sociocultural factors. Community sensitisation, engagement of husbands, pre-established community health worker networks, and trained and supported community health workers facilitated IPTp-SP delivery by community health workers. Incremental cost-effectiveness ratios ranged from $1·1 to $543 per disability-adjusted life-year averted., Interpretation: Community-based approaches increased IPTp-SP coverage and might have a positive effect on the number of antenatal care visits in addition to being cost-effective, although we found high heterogeneity among studies. Community sensitisation and engagement in addition to established, trained, and supported community health workers can facilitate acceptability, delivery, and uptake of IPTp-SP delivered by community health workers., Funding: EDCTP-2 supported by the European Union., Translation: For the French translation of the abstract see Supplementary Materials section., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

This research aimed to produce and analyze zinc oxide nanoparticles (ZNPs) loaded with linalool (LZNPs), and to evaluate their in vitro and in vivo efficacy through targeting the inflammation and oxidative stress. LZNPs were synthesized using an ethanolic solution of polyvinyl alcohol. The Malstat technique was used to evaluate the effectiveness of LZNPs against both sensitive and resistant strains of Plasmosium falciparum. In vivo effects of ZNPs and LZNPs on parasite growth suppression, survival rate, oxidative stress markers, antioxidant genes, and gene and protein levels of inflammatory cytokines were evaluated by Real-time PCR and Western blot techniques. The results indicated that LZNPs demonstrated noteworthy (P < 0.001) antiplasmodial activity against both susceptible and resistant strains of P. falciparum. P. berghei NK65 strain-infected mice treated with the ZNPs and LZNPs at doses of 5-15 mg/kg notably (p < 0.001) increased the survival rates and parasite growth suppression. LZNPs at 5-15 mg/kg demonstrated a significant (p < 0.001) decrease in oxidative stress markers, increased the expression level of antioxidant genes, and reduced the gene and protein expression level of inflammatory cytokines. The current experimental study demonstrated the potent in vitro antiplasmodial activity of LZNPs against chloroquine-resistant and sensitive strains of P. falciparum compared to ZNPs alone. Additionally, the study identified the potential benefits of this nanocomposite in suppressing the parasite and extending the survival rate in mice infected with P. berghei by targeting inflammation and oxidative stress. It also showed minimal toxicity in liver and kidney function in healthy mice. Nevertheless, further research is essential to elucidate the comprehensive mechanisms and practical effectiveness of LZNPs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Increasing antimicrobial resistance (AMR) is a global public health emergency. Although chemoprevention has improved malaria-related pregnancy outcomes, the downstream effects on AMR have not been characterized. We compared the abundance of 10 AMR genes in stool samples from pregnant women receiving sulfadoxine-pyrimethamine (SP) as intermittent preventive treatment against malaria in pregnancy (IPTp) to that in samples from women receiving dihydroartemisinin-piperaquine (DP) for IPTp. All participants had at least one AMR gene at baseline. Mean quantities of the antifolate gene dfrA17 were increased after two or more doses of SP (mean difference = 1.6, 95% CI: 0.4-2.7, P = 0.008). Antimicrobial resistance gene abundance tended to increase from baseline in SP recipients compared with a downward trend in the DP group. Overall, IPTp-SP had minimal effects on the abundance of antifolate resistance genes (except for dfrA17), potentially owing to a high starting prevalence. However, the trend toward increasing AMR in SP recipients warrants further studies.

Background: Perennial malaria chemoprevention (PMC) aims to protect children at risk from severe malaria by the administration of anti-malarial drugs to children of defined ages throughout the year. Sulfadoxine-pyrimethamine (SP) has been widely used for chemoprevention in Africa and a child-friendly dispersible tablet formulation has recently become available., Methods: This qualitative non-interventional observational study was conducted in Benin, Côte d'Ivoire, and Mozambique between February and June 2022. Prototype blister packs, dispensing boxes and job aids designed to support dispersible SP deployment for PMC were evaluated using focus group discussions (FGD) and semi-structured in-depth individual interviews (IDI) with health authorities, health personnel, community health workers (CHWs) and caregivers. The aim was to evaluate knowledge and perceptions of malaria and chemoprevention, test understanding of the tools and identify gaps in understanding, satisfaction, user-friendliness and acceptability, and assess the potential role of CHWs in PMC implementation. Interviews were transcribed and imported to ATLAS.ti for encoding and categorization. Thematic content analysis used deductive and inductive coding with cross-referencing of findings between countries and participants to enrich data interpretation. Continuous comparison across the IDI and FGD permitted iterative, collaborative development of materials., Results: Overall, 106 participants completed IDIs and 70 contributed to FGDs. Malaria was widely recognised as the most common disease affecting children, and PMC was viewed as a positive intervention to support child health. The role of CHWs was perceived differently by the target groups, with caregivers appreciating their trusted status in the community, whereas health authorities preferred clinic-based deployment of PMC by health professionals. Empirical testing of the prototype blister packs, dispensing boxes and job aids highlighted the context-specific expectations of respondents, such as familiar situations and equipment, and identified areas of confusion or low acceptance. A key finding was the need for a clear product identity reflecting malaria., Conclusion: Simple modifications profoundly affected the perception of PMC and influenced acceptability. Iterative quantitative investigation resulted in PMC-specific materials suited to the local context and socio-cultural norms of the target population with the aim of increasing access to chemoprevention in children most at risk of severe malaria., (© 2024. The Author(s).)

Background: Primaquine (PQ) is the prototype 8-aminoquinoline drug, a class which targets gametocytes and hypnozoites. The World Health Organization (WHO) recommends adding a single low dose of primaquine to the standard artemisinin-based combination therapy (ACT) in order to block malaria transmission in regions with low malaria transmission. However, the haemolytic toxicity is a major adverse outcome of primaquine in glucose-6-phosphate dehydrogenase (G6PD)-deficient subjects. This study aimed to characterize the pharmacokinetic properties of primaquine and its major metabolites in G6PD-deficient subjects., Methods: A single low-dose of primaquine (0.4-0.5 mg/kg) was administered in twenty-eight African males. Venous and capillary plasma were sampled up to 24 h after the drug administration. Haemoglobin levels were observed up to 28 days after drug administration. Only PQ, carboxy-primaquine (CPQ), and primaquine carbamoyl-glucuronide (PQCG) were present in plasma samples and measured using liquid chromatography mass spectrometry. Drug and metabolites' pharmacokinetic properties were investigated using nonlinear mixed-effects modelling., Results: Population pharmacokinetic properties of PQ, CPQ, and PQCG can be described by one-compartment disposition kinetics with a transit-absorption model. Body weight was implemented as an allometric function on the clearance and volume parameters for all compounds. None of the covariates significantly affected the pharmacokinetic parameters. No significant correlations were detected between the exposures of the measured compounds and the change in haemoglobin or methaemoglobin levels. There was no significant haemoglobin drop in the G6PD-deficient patients after administration of a single low dose of PQ., Conclusions: A single low-dose of PQ was haematologically safe in this population of G6PD-normal and G6PD-deficient African males without malaria. Trial registration NCT02535767., (© 2024. The Author(s).)

Background: In 2020, during the COVID-19 pandemic, Médecins Sans Frontières (MSF) initiated three cycles of dihydroartemisin-piperaquine (DHA-PQ) mass drug administration (MDA) for children aged three months to 15 years within Bossangoa sub-prefecture, Central African Republic. Coverage, clinical impact, and community members perspectives were evaluated to inform the use of MDAs in humanitarian emergencies., Methods: A household survey was undertaken after the MDA focusing on participation, recent illness among eligible children, and household satisfaction. Using routine surveillance data, the reduction during the MDA period compared to the same period of preceding two years in consultations, malaria diagnoses, malaria rapid diagnostic test (RDT) positivity in three MSF community healthcare facilities (HFs), and the reduction in severe malaria admissions at the regional hospital were estimated. Twenty-seven focus groups discussions (FGDs) with community members were conducted., Results: Overall coverage based on the MDA card or verbal report was 94.3% (95% confidence interval (CI): 86.3-97.8%). Among participants of the household survey, 2.6% (95% CI 1.6-40.3%) of round 3 MDA participants experienced illness in the preceding four weeks compared to 30.6% (95% CI 22.1-40.8%) of MDA non-participants. One community HF experienced a 54.5% (95% CI 50.8-57.9) reduction in consultations, a 73.7% (95% CI 70.5-76.5) reduction in malaria diagnoses, and 42.9% (95% CI 36.0-49.0) reduction in the proportion of positive RDTs among children under five. A second community HF experienced an increase in consultations (+ 15.1% (- 23.3 to 7.5)) and stable malaria diagnoses (4.2% (3.9-11.6)). A third community HF experienced an increase in consultations (+ 41.1% (95% CI 51.2-31.8) and malaria diagnoses (+ 37.3% (95% CI 47.4-27.9)). There were a 25.2% (95% CI 2.0-42.8) reduction in hospital admissions with severe malaria among children under five from the MDA area. FGDs revealed community members perceived less illness among children because of the MDA, as well as fewer hospitalizations. Other indirect benefits such as reduced household expenditure on healthcare were also described., Conclusion: The MDA achieved high coverage and community acceptance. While some positive health impact was observed, it was resource intensive, particularly in this rural context. The priority for malaria control in humanitarian contexts should remain diagnosis and treatment. MDA may be additional tool where the context supports its implementation., (© 2024. The Author(s).)

Background: Plasmodium vivax presents a significant challenge for malaria elimination in the Greater Mekong Subregion. We evaluated the effectiveness of primaquine for reducing relapses of vivax malaria., Methods: Patients with uncomplicated P vivax malaria from eastern Myanmar received chloroquine (25-mg base/kg given in 3 days) plus unsupervised PQ (0.25 mg/kg/d for 14 days) without screening for glucose-6-phosphate dehydrogenase deficiency and were followed for a year., Results: A total of 556 patients were enrolled to receive the chloroquine/primaquine treatment from February 2012 to August 2013. During the follow-up, 38 recurrences were detected, presenting a cumulative recurrence rate of 9.1% (95% CI, 4.1%-14.1%). Genotyping at the pvmsp1 and pvmsp3α loci by amplicon deep sequencing and model prediction indicated that 13 of the 27 recurrences with genotyping data were likely due to relapses. Notably, all confirmed relapses occurred within the first 6 months., Conclusions: The unsupervised standard dose of primaquine was highly effective as a radical cure for P vivax malaria in eastern Myanmar. The high presumed effectiveness might have benefited from the health messages delivered during the enrollment and follow-up activities. Six-month follow-ups in the Greater Mekong Subregion are sufficient for detecting most relapses., Competing Interests: Potential conflicts of interest. All authors: No reported conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest., (© The Author(s) 2023. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

A single 300 mg dose of tafenoquine (an 8-aminoquinoline), in combination with a standard 3-day course of chloroquine, is approved in several countries for the radical cure (prevention of relapse) of Plasmodium vivax malaria in patients aged ≥ 16 years. Despite this, questions have arisen on the optimal dose of tafenoquine. Before the availability of tafenoquine, a 3-day course of chloroquine in combination with the 8-aminoquinoline primaquine was the only effective radical cure for vivax malaria. The World Health Organization (WHO)-recommended standard regimen is 14 days of primaquine 0.25 mg/kg/day or 7 days of primaquine 0.5 mg/kg/day in most regions, or 14 days of primaquine 0.5 mg/kg/day in East Asia and Oceania, however the long treatment courses of 7 or 14 days may result in poor adherence and, therefore, low treatment efficacy. A single dose of tafenoquine 300 mg in combination with a 3-day course of chloroquine is an important advancement for the radical cure of vivax malaria in patients without glucose-6-phosphate dehydrogenase (G6PD) deficiency, as the use of a single-dose treatment will improve adherence. Selection of a single 300 mg dose of tafenoquine for the radical cure of P. vivax malaria was based on collective efficacy and safety data from 33 studies involving more than 4000 trial participants who received tafenoquine, including over 800 subjects who received the 300 mg single dose. The safety profile of single-dose tafenoquine 300 mg is similar to that of standard-dosage primaquine 0.25 mg/kg/day for 14 days. Both primaquine and tafenoquine can cause acute haemolytic anaemia in individuals with G6PD deficiency; severe haemolysis can lead to anaemia, kidney damage, and, in some cases, death. Therefore, relapse prevention using an 8-aminoquinoline must be balanced with the need to avoid clinical haemolysis associated with G6PD deficiency. To minimize this risk, the WHO recommends G6PD testing for all individuals before the administration of curative doses of 8-aminoquinolines. In this article, the authors review key efficacy and safety data from the pivotal trials of tafenoquine and argue that the currently approved dose represents a favourable benefit-risk profile., (© 2024. The Author(s).)

Vaccination of malaria-naive volunteers with a high dose of Plasmodium falciparum sporozoites chemoattenuated by chloroquine (CQ) (PfSPZ-CVac [CQ]) has previously demonstrated full protection against controlled human malaria infection (CHMI). However, lower doses of PfSPZ-CVac [CQ] resulted in incomplete protection. This provides the opportunity to understand the immune mechanisms needed for better vaccine-induced protection by comparing individuals who were protected with those not protected. Using mass cytometry, we characterized immune cell composition and responses of malaria-naive European volunteers who received either lower doses of PfSPZ-CVac [CQ], resulting in 50% protection irrespective of the dose, or a placebo vaccination, with everyone becoming infected following CHMI. Clusters of CD4+ and γδ T cells associated with protection were identified, consistent with their known role in malaria immunity. Additionally, EMRA CD8+ T cells and CD56+CD8+ T cell clusters were associated with protection. In a cohort from a malaria-endemic area in Gabon, these CD8+ T cell clusters were also associated with parasitemia control in individuals with lifelong exposure to malaria. Upon stimulation with P. falciparum-infected erythrocytes, CD4+, γδ, and EMRA CD8+ T cells produced IFN-γ and/or TNF, indicating their ability to mediate responses that eliminate malaria parasites.

Current guidelines advise against primaquine treatment for breastfeeding mothers to avoid the potential for haemolysis in infants with G6PD deficiency. To predict the haemolytic risk, the amount of drug received from the breast milk and the resulting infant drug exposure need to be characterised. Here, we develop a pharmacokinetic model to describe the drug concentrations in breastfeeding women using venous, capillary, and breast milk data. A mother-to-infant model is developed to mimic the infant feeding pattern and used to predict their drug exposures. Primaquine and carboxyprimaquine exposures in infants are <1% of the exposure in mothers. Therefore, even in infants with the most severe G6PD deficiency variants, it is highly unlikely that standard doses of primaquine (0.25-1 mg base/kg once daily given to the mother for 1-14 days) would cause significant haemolysis. After the neonatal period, primaquine should not be restricted for breastfeeding women (Clinical Trials Registration: NCT01780753)., (© 2024. The Author(s).)

Standard diagnostics used in longitudinal antimalarial studies are unable to characterize the complexity of submicroscopic parasite dynamics, particularly in high transmission settings. We use molecular markers and amplicon sequencing to characterize post-treatment stage-specific malaria parasite dynamics during a 42 day randomized trial of 3- versus 5 day artemether-lumefantrine in 303 children with and without HIV (ClinicalTrials.gov number NCT03453840). The prevalence of parasite-derived 18S rRNA is >70% in children throughout follow-up, and the ring-stage marker SBP1 is detectable in over 15% of children on day 14 despite effective treatment. We find that the extended regimen significantly lowers the risk of recurrent ring-stage parasitemia compared to the standard 3 day regimen, and that higher day 7 lumefantrine concentrations decrease the probability of ring-stage parasites in the early post-treatment period. Longitudinal amplicon sequencing reveals remarkably dynamic patterns of multiclonal infections that include new and persistent clones in both the early post-treatment and later time periods. Our data indicate that post-treatment parasite dynamics are highly complex despite efficacious therapy, findings that will inform strategies to optimize regimens in the face of emerging partial artemisinin resistance in Africa., (© 2024. The Author(s).)

Background: Growth of international travel to malarial areas over the last decades has contributed to more travelers taking malaria prophylaxis. Travel-related symptoms may be wrongly attributed to malaria prophylaxis and hinder compliance. Here, we aimed to assess the frequency of real-time reporting of symptoms by travelers following malaria prophylaxis using a smartphone app. Method: Adult international travelers included in this single-center study (Barcelona, Spain) used the smartphone Trip Doctor ® app developed by our group for real-time tracking of symptoms and adherence to prophylaxis. Results: Six hundred four ( n  = 604) international travelers were included in the study; 74.3% (449) used the app daily, and for one-quarter of travelers, malaria prophylaxis was prescribed. Participants from the prophylaxis group traveled more to Africa (86.7% vs. 4.3%; p < 0.01) and to high travel medical risk countries (60.8% vs. 18%; p < 0.01) and reported more immunosuppression (30.8% vs. 23.1% p < 0.01). Regarding symptoms, no significant intergroup differences were observed, and no relationship was found between the total number of malarial pills taken and reported symptoms. Conclusions: In our cohort, the number of symptoms due to malaria prophylaxis was not significantly higher than in participants for whom prophylaxis was not prescribed, and the overall proportion of symptoms is higher compared with other studies.

Background: The cornerstone of malaria prevention in pregnancy, intermittent preventive treatment (IPTp) with sulfadoxine-pyrimethamine, is contraindicated in women with HIV who are receiving co-trimoxazole prophylaxis. We assessed whether IPTp with dihydroartemisinin-piperaquine is safe and effective in reducing the risk of malaria infection in women with HIV receiving co-trimoxazole prophylaxis and antiretroviral drugs., Methods: For this randomised, double-blind, placebo-controlled clinical trial, women with HIV attending the first antenatal care clinic visit, resident in the study area, and with a gestational age up to 28 weeks were enrolled at five sites in Gabon and Mozambique. Participants were randomly assigned (1:1) to receive either IPTp with dihydroartemisinin-piperaquine at each scheduled antenatal care visit plus daily co-trimoxazole (intervention group) or placebo at each scheduled antenatal care visit plus daily co-trimoxazole (control group). Randomisation was done centrally via block randomisation (block sizes of eight), stratified by country. IPTp was given over 3 days under direct observation by masked study personnel. The number of daily IPTp tablets was based on bodyweight and according to the treatment guidelines set by WHO (target dose of 4 mg/kg per day [range 2-10 mg/kg per day] of dihydroartemisinin and 18 mg/kg per day [range 16-27 mg/kg per day] of piperaquine given once a day for 3 days). At enrolment, all participants received co-trimoxazole (fixed combination drug containing 800 mg trimethoprim and 160 mg sulfamethoxazole) for daily intake. The primary study outcome was prevalence of peripheral parasitaemia detected by microscopy at delivery. The modified intention-to-treat population included all randomly assigned women who had data for the primary outcome. Secondary outcomes included frequency of adverse events, incidence of clinical malaria during pregnancy, and frequency of poor pregnancy outcomes. All study personnel, investigators, outcome assessors, data analysts, and participants were masked to treatment assignment. This study is registered with ClinicalTrials.gov, NCT03671109., Findings: From Sept 18, 2019, to Nov 26, 2021, 666 women (mean age 28·5 years [SD 6·4]) were enrolled and randomly assigned to the intervention (n=332) and control (n=334) groups. 294 women in the intervention group and 308 women in the control group had peripheral blood samples taken at delivery and were included in the primary analysis. Peripheral parasitaemia at delivery was detected in one (<1%) of 294 women in the intervention group and none of 308 women in the control group. The incidence of clinical malaria during pregnancy was lower in the intervention group than in the control group (one episode in the intervention group vs six in the control group; relative risk [RR] 0·12, 95% CI 0·03-0·52, p=0·045). In a post-hoc analysis, the composite outcome of overall malaria infection (detected by any diagnostic test during pregnancy or delivery) was lower in the intervention group than in the control group (14 [5%] of 311 women vs 31 [10%] of 320 women; RR 0·48, 95% CI 0·27-0·84, p=0·010). The frequency of serious adverse events and poor pregnancy outcomes (such as miscarriages, stillbirths, premature births, and congenital malformations) did not differ between groups. The most frequently reported drug-related adverse events were gastrointestinal disorder (reported in less than 4% of participants) and headache (reported in less than 2% of participants), with no differences between study groups., Interpretation: In the context of low malaria transmission, the addition of IPTp with dihydroartemisinin-piperaquine to co-trimoxazole prophylaxis in pregnant women with HIV did not reduce peripheral parasitaemia at delivery. However, the intervention was safe and associated with a decreased risk of clinical malaria and overall Plasmodium falciparum infection, so it should be considered as a strategy to protect pregnant women with HIV from malaria., Funding: European and Developing Countries Clinical Trials Partnership 2 (EDCTP2) and Medicines for Malaria Venture., Translations: For the Portuguese and French translations of the abstract see Supplementary Materials section., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

We reported here on the development of a pharmacometric framework to assess patient adherence, by using two population-based approaches - the percentile and the Bayesian method. Three different dosing strategies were investigated in patients prescribed a total of three doses; (1) non-observed therapy, (2) directly observed administration of the first dose, and (3) directly observed administration of the first two doses. The percentile approach used population-based simulations to derive optimal concentration percentile cutoff values from the distribution of simulated drug concentrations at a specific time. This was done for each adherence scenario and compared to full adherence. The Bayesian approach calculated the posterior probability of each adherence scenario at a given drug concentration. The predictive performance (i.e., Youden index, receiver operating characteristic [ROC] curve) of both approaches were highly influenced by sample collection time (early was better) and interindividual variability (smaller was better). The complexity of the structural model and the half-life had a minimal impact on the predictive performance of these methods. The impact of the assay limitation (LOQ) on the predictive performance was relatively small if the fraction of LOQ data was less than 20%. Overall, the percentile method performed similar or better for adherence predictions compared to the Bayesian approach, with the latter showing slightly better results when investigating the adherence to the last dose only. The percentile approach showed acceptable adherence predictions (area under ROC curve > 0.74) when sampling the antimalarial drugs piperaquine at day 7 postdose and lumefantrine at day 3 postdose (i.e., 12 h after the last dose). This could be a highly useful approach when evaluating programmatic implementations of preventive and curative antimalarial treatment programs in endemic areas., (© 2024 The Authors. CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals LLC on behalf of American Society for Clinical Pharmacology and Therapeutics.)

Background Objectives: 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., Methods: 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., Results: 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., Interpretation Conclusion: 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., (Copyright © 2024 Copyright: © 2024 Journal of Vector Borne Diseases.)

Malaria remains a significant cause of morbidity and mortality, even in low-transmission settings. With the advent of longer acting, more effective, and well-tolerated antimalarials, there is renewed interest in the efficacy of mass drug administration (MDA) to accelerate to elimination. We conducted a systematic review and meta-analysis to assess the efficacy of MDA to reduce the incidence and prevalence of Plasmodium falciparum (Pf) and Plasmodium vivax (Pv) infection. From 1,044 articles screened, 14 articles, including 10 randomized controlled trials (RCTs), were identified. Five included data on Pf only; five included Pf and Pv. Two of the Pf studies were conducted in areas of high-moderate transmission, the remainder were in areas of low-very low transmission. In higher transmission areas, MDA reduced incidence of Pf parasitemia (rate ratio = 0.61, 95% CI: 0.40-0.92; moderate certainty) 1 to 3 months after drug administration; no significant effect of MDA on Pf parasitemia prevalence was detected 1 to 3 months post-MDA (risk ratio [RR] = 1.76, 95% CI: 0.58-5.36; low certainty). In lower transmission settings, both incidence and prevalence of Pf parasitemia were reduced 1 to 3 months post-MDA (rate ratio = 0.37, 95% CI: 0.21-0.66; RR = 0.25, 95% CI: 0.15-0.41, respectively). Pv prevalence was reduced 1 to 3 months post-MDA (RR = 0.15, 95% CI: 0.10-0.24); there were no RCTs providing data on incidence of Pv. There was no significant effect of MDA at later time points. MDA may have short-term benefits; however, there was no evidence for longer term impact, although none of the trials assessed prolonged interventions.

Many countries pursuing malaria elimination implement "reactive" strategies targeting household members and neighbors of index cases to reduce transmission. These strategies include reactive case detection and treatment (RACDT; testing and treating those positive) and reactive drug administration (RDA; providing antimalarials without testing). We conducted systematic reviews of RACDT and RDA to assess their effect on reducing malaria transmission and gathered evidence about key contextual factors important to their implementation. Two reviewers screened titles/abstracts and full-text records using defined criteria (Patient = those in malaria-endemic/receptive areas; Intervention = RACDT or RDA; Comparison = standard of care; Outcome = malaria incidence/prevalence) and abstracted data for meta-analyses. The Grading of Recommendations, Assessment, Development, and Evaluations approach was used to rate certainty of evidence (CoE) for each outcome. Of 1,460 records screened, reviewers identified five RACDT studies (three cluster-randomized controlled trials [cRCTs] and two nonrandomized studies [NRS]) and seven RDA studies (six cRCTs and one NRS); three cRCTs comparing RDA to RACDT were included in both reviews. Compared with RDA, RACDT was associated with nonsignificantly higher parasite prevalence (odds ratio [OR] = 1.85; 95% CI: 0.96-3.57; one study) and malaria incidence (rate ratio [RR] = 1.30; 95% CI: 0.94-1.79; three studies), both very low CoE. Compared with control or RACDT, RDA was associated with non-significantly lower parasite incidence (RR = 0.73; 95% CI: 0.36-1.47; 2 studies, moderate CoE), prevalence (OR = 0.78; 95% CI: 0.52-1.17; 4 studies, low CoE), and malaria incidence (RR = 0.93; 95% CI: 0.82-1.05; six studies, moderate CoE). Evidence for reactive strategies' impact on malaria transmission is limited, especially for RACDT, but suggests RDA might be more effective.

Uncomplicated malaria is effectively treated with oral artemisinin-based combination therapy (ACT). Yet, there is an unmet clinical need for the intravenous treatment of the more fatal severe malaria. There is no combination intravenous therapy for uncomplicated due to the nonavailability of a water-soluble partner drug for the artemisinin, artesunate. The currently available treatment is a two-part regimen split into an intravenous artesunate followed by the conventional oral ACT . In a novel application of polymer therapeutics, the aqueous insoluble antimalarial lumefantrine is conjugated to a carrier polymer to create a new water-soluble chemical entity suitable for intravenous administration in a clinically relevant formulation . The conjugate is characterized by spectroscopic and analytical techniques, and the aqueous solubility of lumefantrine is determined to have increased by three orders of magnitude. Pharmacokinetic studies in mice indicate that there is a significant plasma release of lumefantrine and production its metabolite desbutyl-lumefantrine (area under the curve of metabolite is ≈10% that of the parent). In a Plasmodium falciparum malaria mouse model, parasitemia clearance is 50% higher than that of reference unconjugated lumefantrine. The polymer-lumefantrine shows potential for entering the clinic to meet the need for a one-course combination treatment for severe malaria., (© 2023 The Authors. Macromolecular Bioscience published by Wiley-VCH GmbH.)

Background: An estimated 300,000 babies are born with sickle cell anaemia (SCA) annually. Affected children have chronic ill health and suffer premature death. Febrile illnesses such as malaria commonly precipitate acute crises in children with SCA. Thus, chemoprophylaxis for malaria is an important preventive strategy, but current regimes are either sub-optimally effective (e.g. monthly sulphadoxine-pyrimethamine, SP) or difficult to adhere to (e.g. daily proguanil). We propose dihydroartemisinin-piperaquine (DP) as the agent with the most potential to be used across Africa., Methods: This will be a randomised, double-blind, parallel-group superiority trial of weekly single-day courses of DP compared to monthly single-day courses of SP in children with SCA. The study will be conducted in eastern (Uganda) and southern (Malawi) Africa using randomisation stratified by body weight and study centre. Participants will be randomised using an allocation of 1:1 to DP or SP. We will investigate the efficacy, safety, acceptability and uptake and cost-effectiveness of malaria chemoprevention with weekly courses of DP vs monthly SP in 548 to 824 children with SCA followed up for 12-18 months. We will also assess toxicity from cumulative DP dosing and the development of resistance. Participant recruitment commenced on 30 April 2021; follow-up is ongoing., Discussion: At the end of this study, findings will be used to inform regional health policy. This manuscript is prepared from protocol version 2.1 dated 1 January 2022., Trial Registration: The trial was registered at ClinicalTrials.gov, NCT04844099 . Registered on 08 April 2021., (© 2023. The Author(s).)

Ethnopharmacological Relevance: Aconitum heterophyllum Wall. ex Royle is a traditionally important medicinal plant having numerous therapeutic actions as documented in Ayurveda. This plant is traditionally known for combating worm infestation, fever, respiratory tract disease, vomiting, diarrhoea, diabetes, skin disorders, anaemia, and joint disorders. Further, it has been used alone and in combination with other plants to prepare various anti-malarial formulations. However, there is no report on the assessment of its anti-plasmodial activity, and the metabolite(s) responsible for this activity., Aim of the Study: The main aim of this study was to conduct phytochemical investigation of A. heterophyllum roots for the preparation of extract, fractions, and isolation of pure molecules to identify active fractions/molecules responsible for the anti-plasmodial activity, and development of UHPLC-DAD based analytical method which can be used for the quantification of marker compounds in the extracts and fractions., Materials and Methods: Hydroalcoholic extract (1:1 v/v) and fractions (n-hexane, chloroform, ethyl acetate, n-butanol, and water) were prepared from the dried powdered roots of A. heterophyllum. Fractions were further subjected to silica gel column chromatography to isolate pure specialized secondary metabolites from this plant. All extracts, fractions, and pure molecules were evaluated against the chloroquine resistant Pf INDO and chloroquine sensitive Pf3D7 strains in culture for calculating their IC 50 values. UHPLC-DAD based analytical method was also developed for the first time for the quantification of marker compounds and quality assessment of this commercially important Himalayan medicinal plant., Results: Phytochemical investigation of A. heterophyllum root led to the isolation of six specialized metabolites viz. 2-O-cinnamoyl hetisine (1), atisinium (2), 4-oxabicyclo [3.2.2] nona-1(7),5,8-triene (3), atisinium cinnamate (4), aconitic acid (5), and atisinium formate (6). Compound 1 is a new hetisine type diterpenoid alkaloid, compounds 4 and 6 are new counter ionic forms observed with atisinium ion, and compound 3 is being reported for the first time from this genus. Chloroform fraction was found to be the most active with IC 50 (μg/mL) 1.01 (Pf INDO) and 1.32 (Pf3D7). The molecule 2-O-cinnamoyl hetisine (1), a new diterpenoid alkaloid isolated from chloroform fraction, showed promising antiplasmodial activities with IC 50 (μM) 1.92 (Pf INDO) and 10.8 (Pf 3D7). The activity of chloroform fraction was further validated by the developed UHPLC-DAD based method as the quantity of 2-O-cinnamoyl hetisine (1) was higher in the chloroform fraction (≅200 mg/g) than in all other fractions (<7 mg/g). Atisinium (2) and 2-O-cinnamoyl hetisine (1) were found to be the main marker compounds of this plant based on quantity and antiplasmodial activity, respectively., Conclusion: This study provides the scientific rationale for the traditional use of this plant in treating malaria. Further, this study revealed that the anti-malarial potential of this plant might be due to the presence of diterpenoid alkaloids., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: Although the malaria burden has substantially decreased in sub-Saharan Africa, progress has stalled. We assessed whether mass administration of ivermectin (a mosquitocidal drug) and dihydroartemisinin-piperaquine (an antimalarial treatment) reduces malaria in The Gambia, an area with high coverage of standard control interventions., Methods: This open-label, cluster-randomised controlled trial was done in the Upper River region of eastern Gambia. Villages with a baseline Plasmodium falciparum prevalence of 7-46% (all ages) and separated from each other by at least 3 km to reduce vector spillover were selected. Inclusion criteria were age and anthropometry (for ivermectin, weight of ≥15 kg; for dihydroartemisinin-piperaquine, participants older than 6 months); willingness to comply with trial procedures; and written informed consent. Villages were randomised (1:1) to either the intervention (ivermectin [orally at 300-400 μg/kg per day for 3 consecutive days] and dihydroartemisinin-piperaquine [orally depending on bodyweight] plus standard control interventions) or the control group (standard control interventions) using computer-based randomisation. Laboratory staff were masked to the origin of samples. In the intervention group, three rounds of mass drug administration once per month with ivermectin and dihydroartemisinin-piperaquine were given during two malaria transmission seasons from Aug 27 to Oct 31, 2018, and from July 15 to Sept 30, 2019. Primary outcomes were malaria prevalence by qPCR at the end of the second intervention year in November 2019, and Anopheles gambiae (s l) parous rate, analysed in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT03576313., Findings: Between Nov 20 and Dec 7, 2017, 47 villages were screened for eligibility in the study. 15 were excluded because the baseline malaria prevalence was less than 7% (figure 1). 32 villages were enrolled and randomised to either the intervention or control group (n=16 in each group). The study population was 10 638, of which 4939 (46%) participants were in intervention villages. Coverage for dihydroartemisinin-piperaquine was between 49·0% and 58·4% in 2018, and between 76·1% and 86·0% in 2019; for ivermectin, coverage was between 46·9% and 52·2% in 2018, and between 71·7% and 82·9% in 2019. In November 2019, malaria prevalence was 12·8% (324 of 2529) in the control group and 5·1% (140 of 2722) in the intervention group (odds ratio [OR] 0·30, 95% CI 0·16-0·59; p<0·001). A gambiae (s l) parous rate was 83·1% (552 of 664) in the control group and 81·7% (441 of 540) in the intervention group (0·90, 0·66-1·25; p=0·537). In 2019, adverse events were recorded in 386 (9·7%) of 3991 participants in round one, 201 (5·4%) of 3750 in round two, and 168 (4·5%) of 3752 in round three. None of the 11 serious adverse events were related to the intervention., Interpretation: The intervention was safe and well tolerated. In an area with high coverage of standard control interventions, mass drug administration of ivermectin and dihydroartemisinin-piperaquine significantly reduced malaria prevalence; however, no effect of ivermectin on vector parous rate was observed., Funding: Joint Global Health Trials Scheme., Translation: For the French translation of the abstract see Supplementary Materials section., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Background: In most of the Americas, the recommended treatment to prevent relapse of Plasmodium vivax malaria is primaquine at a total dose of 3.5 mg per kilogram of body weight, despite evidence of only moderate efficacy., Methods: In this trial conducted in Brazil, we evaluated three primaquine regimens to prevent relapse of P. vivax malaria in children at least 5 years of age and in adults with microscopy-confirmed P. vivax monoinfection. All the patients received directly observed chloroquine for 3 days (total dose, 25 mg per kilogram). Group 1 received a total primaquine dose of 3.5 mg per kilogram (0.5 mg per kilogram per day) over 7 days with unobserved administration; group 2 received the same regimen as group 1 but with observed administration; and group 3 received a total primaquine dose of 7.0 mg per kilogram over 14 days (also 0.5 mg per kilogram per day) with observed administration. We monitored the patients for 168 days., Results: We enrolled 63 patients in group 1, 96 in group 2, and 95 in group 3. The median age of the patients was 22.4 years (range, 5.4 to 79.8). By day 28, three P. vivax recurrences were observed: 2 in group 1 and 1 in group 2. By day 168, a total of 70 recurrences had occurred: 24 in group 1, 34 in group 2, and 12 in group 3. No serious adverse events were noted. On day 168, the percentage of patients without recurrence was 58% (95% confidence interval [CI], 44 to 70) in group 1, 59% (95% CI, 47 to 69) in group 2, and 86% (95% CI, 76 to 92) in group 3. Survival analysis showed a difference in the day 168 recurrence-free percentage of 27 percentage points (97.5% CI, 10 to 44; P<0.001) between group 1 and group 3 and a difference of 27 percentage points (97.5% CI, 12 to 42; P<0.001) between group 2 and group 3., Conclusions: The administration of primaquine at a total dose of 7.0 mg per kilogram had higher efficacy in preventing relapse of P. vivax malaria than a total dose of 3.5 mg per kilogram through day 168. (Supported by the U.S. Agency for International Development; ClinicalTrials.gov number, NCT03610399.)., (Copyright © 2022 Massachusetts Medical Society.)

Background: Low birth weight is a public health problem in Africa with the cause attributable to malaria in pregnancy. World Health Organization recommends the use of intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine to prevent malaria during pregnancy. The objective of this study was to evaluate the prevalence and trajectories of birth weight and the direct impact and relationship between sulfadoxine-pyrimethamine and birth weight in Ghana since 2003., Method: This study used secondary data obtained from the Demographic and Health Survey conducted in Ghana since 2003. Low birth weight was defined as weight < 2500 g irrespective of the gestational age of the foetus, while normal birth weight was between 2500 g to < 4000 g and macrosomia was =  > 4000 g. In all the analysis, we adjusted for clustering, stratification and weighting to reduce bias and improve precision of the estimates. Analysis was performed on each survey year as well as the pooled dataset. The generalized ordered partial proportional odds model was used due to violations of the parallel regression model assumptions. Efforts were made to identify all confounding variables and these were adjusted for. Predictive analysis was also executed., Results: The overall prevalence of low birth weight was 9% while that of macrosomia was 13%. The low birth weight for 2003 was 12% while in 2008 it was 21% and then 68% in 2014. The mean birth weight of the children in 2014 was 3.16 (3.14, 3.19), 2008 was 3.37 (3.28, 3.45) and 2003 was 3.59 (3.49, 3.69) while that of the pooled data was 3.28 (3.25, 3.30). The adjusted model (taking into consideration all confounding variables) showed that non-uptake of SP could result in 51% odds of giving birth to a low-birth-weight compared with normal birth weight child. An insignificant result was observed between macrosomia and low birth weight., Conclusion: There is higher probability that low birth weight could increase over the next couple of years if measures are not taking to reverse the current trajectories. The uptake of sulfadoxine-pyrimethamine should continue to be encouraged and recommended because it has a direct beneficial effect on the weight of the child., (© 2022. The Author(s).)

Artemisinin-hydroxychloroquine sulfate tablets (AH) are considered a relatively inexpensive and novel combination therapy for treating all forms of malaria, especially aminoquinoline drugs-resistant strains of P.falciparum. We aim to carry out acute and subacute oral toxicity studies in rats to acquire preclinical data on the safety of AH. Acute toxicity was evaluated in Sprague-Dawley (SD) rats at a single dose of 1980, 2970, 4450, 6670, and 10000 mg/kg. A 14-days subacute toxicity was assessed in SD rats at doses of 0, 146, 219, 328, and 429 mg/kg. The median lethal dose (LD 50 ) of acute oral administration of AH in rats is found to be 3119 mg/kg, and toxic symptoms include decreased spontaneous activity, dyspnea, bristling, soft feces, spasticity, and convulsion. Repeated doses of AH have toxic effects on the nervous system, skin, blood system, liver, kidney, and spleen in rats. The main toxic reactions include epilation, emaciation, mental irritability, decreased body weight gain and food consumption, changes in the hematological and biochemical parameters, especially pathological lesions in the liver, kidney, and spleen. The no-observed-adverse-effect level (NOAEL) and lowest-observed-adverse-effect level (LOAEL) of AH are considered to be 219 mg/kg and 328 mg/kg, respectively., (Copyright © 2022 Elsevier Inc. All rights reserved.)

In vitro screening for pharmacological activity of existing drugs showed chloroquine and hydroxychloroquine to be effective against severe acute respiratory syndrome coronavirus 2. Oral administration of these compounds to obtain desired pulmonary exposures resulted in dose-limiting systemic toxicity in humans. However, pulmonary drug delivery enables direct and rapid administration to obtain higher local tissue concentrations in target tissue. In this work, inhalable formulations for thermal aerosolization of chloroquine and hydroxychloroquine were developed, and their physicochemical properties were characterized. Thermal aerosolization of 40 mg/mL chloroquine and 100 mg/mL hydroxychloroquine formulations delivered respirable aerosol particle sizes with 0.15 and 0.33 mg per 55 mL puff, respectively. In vitro toxicity was evaluated by exposing primary human bronchial epithelial cells to aerosol generated from Vitrocell. An in vitro exposure to 7.24 μg of chloroquine or 7.99 μg hydroxychloroquine showed no significant changes in cilia beating, transepithelial electrical resistance, and cell viability. The pharmacokinetics of inhaled aerosols was predicted by developing a physiologically based pharmacokinetic model that included a detailed species-specific respiratory tract physiology and lysosomal trapping. Based on the model predictions, inhaling emitted doses comprising 1.5 mg of chloroquine or 3.3 mg hydroxychloroquine three times a day may yield therapeutically effective concentrations in the lung. Inhalation of higher doses further increased effective concentrations in the lung while maintaining lower systemic concentrations. Given the theoretically favorable risk/benefit ratio, the clinical significance for pulmonary delivery of aerosolized chloroquine and hydroxychloroquine to treat COVID-19 needs to be established in rigorous safety and efficacy studies. Graphical abstract., (© 2021. The Author(s).)

Background: Single-dose tafenoquine 300 mg is approved for Plasmodium vivax malaria relapse prevention in patients at least 16 years old. We aimed to determine appropriate oral tafenoquine paediatric dosing regimens, including a dispersible formulation, and evaluated tafenoquine efficacy and safety in children infected with P vivax., Methods: This open-label, single-arm, non-comparative, multicentre, pharmacokinetic bridging, phase 2 study enrolled children (2-15 years) who weighed 5 kg or more, with glucose-6-phosphate dehydrogenase activity more than 70% of the local population median, and P vivax malaria infection, from three community health centres in Vietnam and one in Colombia. Patients received 3-day chloroquine plus oral single-dose tafenoquine as dispersible tablets (50 mg) or film-coated tablets (150 mg). Dosing groups were assigned by body weight, predicted to achieve similar median exposures as the approved 300 mg dose for adults: patients who weighed 5 kg or more to 10 kg received 50 mg, those who weighed more than 10 to 20 kg received 100 or 150 mg, those who weighed more than 20 to 35 kg received 200 mg, and patients who weighed more than 35 kg received 300 mg. Population pharmacokinetic analysis was done to develop a paediatric population pharmacokinetic model. The primary outcome was the tafenoquine area under the concentration-time curve extrapolated to infinity (AUC [0-∞] ) by patient body weight in the pharmacokinetic population (all patients who received tafenoquine with at least one valid pharmacokinetic sample) estimated from a paediatric population pharmacokinetic model. A key prespecified secondary outcome was 4-month recurrence-free efficacy. This trial is registered with ClinicalTrials.gov, NCT02563496., Findings: Between Feb 6, 2017, and Feb 17, 2020, 60 patients were enrolled into the study: 14 (23%) received tafenoquine 100 mg, five (8%) 150 mg, 22 (36%) 200 mg, and 19 (32%) 300 mg. The paediatric population pharmacokinetic model predicted adequate tafenoquine exposure at all doses. The predicted median AUC (0-∞) was 73·8 (90% prediction interval [PI] 46·9-117·0) μg × h/mL with the 50 mg dose for patients who weighed 5 kg or more to 10 kg, 87·5 (55·4-139·0) μg × h/mL with the 100 mg dose for body weight more than 10 to 20 kg, 110·7 (70·9-174·0) μg × h/mL with the 200 mg dose for body weight more than 20 to 35 kg, and 85·7 (50·6-151·0) μg × h/mL with the 300 mg dose for body weight more than 35 kg. 4-month recurrence-free efficacy was 94·7% (95% CI 84·6-98·3). Adverse events were consistent with previous studies, except for the seven (12%) of 60 patients who had post-dose vomiting or spitting with the 50 mg dispersed tablet. Following mitigation strategies, there were no additional occurrences of this adverse event. There were no deaths during the study., Interpretation: For the prevention of P vivax relapse in children, single-dose tafenoquine, including a dispersible formulation, had exposure, safety, and efficacy consistent with observations in adolescents and adults, notwithstanding post-dose vomiting., Funding: GlaxoSmithKline and Medicines for Malaria Venture., Translations: For the Vietnamese and Spanish translations of the abstract see Supplementary Materials section., Competing Interests: Declaration of interests IDV and TTH report funding from GlaxoSmithKline and Medicines for Malaria Venture for the TEACH clinical trial. AM, HS, VMR, JJB, TBE, KR, MT, KM, SWJ, NG and LKT are employees of GlaxoSmithKline and hold shares in the company. JAG is a former employee of GlaxoSmithKline and holds shares in the company. SD is an employee of Medicines for Malaria Venture. All other authors declare no competing interests., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

In malaria, anti-parasite immune response of the host may lead to dysregulated inflammation causing severe neuropathology arising from extensive damage to the Blood Brain Barrier (BBB). Use of anti-malarial drugs alone can control parasitemia and reduce inflammation but it cannot reduce pathology if chronic inflammation has already set in. In the present study, we have tested the efficacy of a new oral artemsinin based combination therapy (ACT) regimen using a combination of anti-malarial compounds like nanoartemisinin and nanoallylated-chalcone9 [{1-(4-Chlorophenyl)-3-[3-methoxy-4-(prop-2-en-1-yloxy) phenyl]-prop-2-en-1-one}]given together with anti-inflammatory-cum- anti-malarial compounds like nanoandrographolide and nanocurcumin to C57BL/6 mice infected with P. berghei ANKA. Untreated infected mice developed Experimental Cerebral Malaria (ECM) and died between 10 to 12 days after infection from severe BBB damage. We observed that oral treatments with nanoartemisinin or nano allylated chalcone 9 or nanoandrographolide alone, for 4 days after the onset of ECM, delayed the development of severe neurolopathology but could not prevent it. Nanocurcumin treatment for 4 days on the other hand, prevented damage to the BBB but the mice died because of hyperparasitemia. A single time oral administration of our ACT controlled blood parasitemia and prevented damage to the BBB, but recrudescence occurred due to persistence of parasites in the spleen. However the recrudescent parasites failed to induce ECM and BBB damage, leading to prolonged survival of the animals. A second time treatment at the start of recrudescence led to complete parasite clearance and survival of mice without pathology or parasitemia for 90 days. FACS analysis of spleen cells and gene expression profile in brain and spleen as well as quantitation of serum cytokine by ELISA showed that P. berghei ANKA infection in C57Bl/6 mice leads to a Th1-skewed immune response that result in severe inflammation and early death from ECM. Oral treatment with our ACT prevented a heightened pro-inflammatory response by modulating the Th1, Th2 and Treg immune responses and prevented ECM and death., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Mukherjee, Ray, Saha and Kar.)

Patients with cerebral malaria with polymorphic Cytochrome P450 2C19 (CYP2C19) genotypes who receive concurrent treatment with quinine are at risk of inadequate or toxic therapeutic drug concentrations due to metabolic drug interactions. The study aimed to predict the potential dose regimens of quinine when coadministered with phenobarbital in adult patients with cerebral malaria and complications (e.g., lactic acidosis and acute renal failure) and concurrent with seizures and acute renal failure who carry wild-type and polymorphic CYP2C19. The whole-body physiologically based pharmacokinetic (PBPK) models for quinine, phenobarbital, and quinine-phenobarbital coadministration were constructed based on the previously published information using Simbiology®. Four published articles were used for model validation. A total of 100 virtual patients were simulated based on the 14-day and 3-day courses of treatment. using the drug-drug interaction approach. The predicted results were within 15% of the observed values. Standard phenobarbital dose, when administered with quinine, is suitable for all groups with single or continuous seizures regardless of CYP2C19 genotype, renal failure, and lactic acidosis. Dose adjustment based on area under the curve ratio provided inappropriate quinine concentrations. The recommended dose of quinine when coadministered with phenobarbital based on the PBPK model for all groups is a loading dose of 2000 mg intravenous (i.v.) infusion rate 250 mg/h followed by 1200 mg i.v. rate 150 mg/h. The developed PBPK models are credible for further simulations. Because the predicted quinine doses in all groups were similar regardless of the CYP2C19 genotype, genotyping may not be required., (© 2021 The Authors. CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals LLC on behalf of American Society for Clinical Pharmacology and Therapeutics.)