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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 studys findings indicate that using SLD-PQ in combination with ACT is safe for uncomplicated P. falciparum malaria regardless of the patients G6PD status in Ethiopian settings. Caution should be taken in extrapolating this finding in other settings with diverse G6DP phenotypes.

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.

BACKGROUND: Artemisinin resistance in Plasmodium falciparum threatens global malaria elimination efforts. To contain and then eliminate artemisinin resistance in Eastern Myanmar a network of community-based malaria posts was instituted and targeted mass drug administration (MDA) with dihydroartemisinin-piperaquine (three rounds at monthly intervals) was conducted. The prevalence of artemisinin resistance during the elimination campaign (2013-2019) was characterized. METHODS: Throughout the six-year campaign Plasmodium falciparum positive blood samples from symptomatic patients and from cross-sectional surveys were genotyped for mutations in kelch-13-a molecular marker of artemisinin resistance. RESULT: The program resulted in near elimination of falciparum malaria. Of 5162 P. falciparum positive blood samples genotyped, 3281 (63.6%) had K13 mutations. The prevalence of K13 mutations was 73.9% in 2013 and 64.4% in 2019. Overall, there was a small but significant decline in the proportion of K13 mutants (p

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.

INTRODUCTION: As malaria declines, low-density malaria infections (LMIs) represent an increasing proportion of infections and may have negative impacts on child health and cognition, necessitating development of targeted and effective solutions. This trial assesses the health, cognitive and socioeconomic impact of two strategies for detecting and treating LMI in a low transmission setting. METHODS AND ANALYSIS: The study is a 3-arm open-label individually randomised controlled trial enrolling 600 children aged 6 months to 10 years in Bagamoyo district, Tanzania. Children are randomised to one of three arms: active case detection with molecular (ACDm) testing by high volume quantitative PCR (qPCR), passive case detection also with molecular testing (PCDm) and a control of standard PCD using rapid diagnostics tests (RDTs). Over the 2-year trial, ACDm participants receive malaria testing using RDT and qPCR three times annually, and malaria testing by RDT only when presenting with fever. PCDm and PCD participants receive malaria testing by RDT and qPCR or RDT only, respectively, when presenting with fever. RDT or qPCR positive participants with uncomplicated malaria are treated with artemether lumefantrine. The primary outcome is cumulative incidence of all-cause sick visits. Secondary outcomes include fever episodes, clinical failure after fever episodes, adverse events, malaria, non-malarial infection, antibiotic use, anaemia, growth faltering, cognition and attention, school outcomes, immune responses, and socioeconomic effects. Outcomes are assessed through monthly clinical assessments and testing, and baseline and endline neurodevelopmental testing. The trial is expected to provide key evidence and inform policy on health, cognitive and socioeconomic impact of interventions targeting LMI in children. ETHICS AND DISSEMINATION: Study is approved by Tanzania NatHREC and institutional review boards at University of California San Francisco and Ifakara Health Institute. Findings will be reported on ClinicalTrials.gov, in peer-reviewed journals and through stakeholder meetings. TRIAL REGISTRATION NUMBER: NCT05567016.

Malaria elimination requires interventions able to target both the asexual blood stage (ABS) parasites and transmissible gametocyte stages of Plasmodium falciparum. Lead antimalarial candidates are evaluated against clinical isolates to address key concerns regarding efficacy and to confirm that the current, circulating parasites from endemic regions lack resistance against these candidates. While this has largely been performed on ABS parasites, limited data are available on the transmission-blocking efficacy of compounds with multistage activity. Here, we evaluated the efficacy of lead antimalarial candidates against both ABS parasites and late-stage gametocytes side-by-side, against clinical P. falciparum isolates from southern Africa. We additionally correlated drug efficacy to the genetic diversity of the clinical isolates as determined with a panel of well-characterized, genome-spanning microsatellite markers. Our data indicate varying sensitivities of the isolates to key antimalarial candidates, both for ABS parasites and gametocyte stages. While ABS parasites were efficiently killed, irrespective of genetic complexity, antimalarial candidates lost some gametocytocidal efficacy when the gametocytes originated from genetically complex, multiple-clone infections. This suggests a fitness benefit to multiclone isolates to sustain transmission and reduce drug susceptibility. In conclusion, this is the first study to investigate the efficacy of antimalarial candidates on both ABS parasites and gametocytes from P. falciparum clinical isolates where the influence of parasite genetic complexity is highlighted, ultimately aiding the malaria elimination agenda.

Our previous study identified 52 antiplasmodial peptaibols isolated from fungi. To understand their antiplasmodial mechanism of action, we conducted phenotypic assays, assessed the in vitro evolution of resistance, and performed a transcriptome analysis of the most potent peptaibol, HZ NPDG-I. HZ NPDG-I and 2 additional peptaibols were compared for their killing action and stage dependency, each showing a loss of digestive vacuole (DV) content via ultrastructural analysis. HZ NPDG-I demonstrated a stepwise increase in DV pH, impaired DV membrane permeability, and the ability to form ion channels upon reconstitution in planar membranes. This compound showed no signs of cross resistance to targets of current clinical candidates, and 3 independent lines evolved to resist HZ NPDG-I acquired nonsynonymous changes in the P. falciparum multidrug resistance transporter, pfmdr1. Conditional knockdown of PfMDR1 showed varying effects to other peptaibol analogs, suggesting differing sensitivity.

Malaria poses an enormous threat to human health. With ever increasing resistance to currently deployed drugs, breakthrough compounds with novel mechanisms of action are urgently needed. Here, we explore pyrimidine-based sulfonamides as a new low molecular weight inhibitor class with drug-like physical parameters and a synthetically accessible scaffold. We show that the exemplar, OSM-S-106, has potent activity against parasite cultures, low mammalian cell toxicity and low propensity for resistance development. In vitro evolution of resistance using a slow ramp-up approach pointed to the Plasmodium falciparum cytoplasmic asparaginyl-tRNA synthetase (PfAsnRS) as the target, consistent with our finding that OSM-S-106 inhibits protein translation and activates the amino acid starvation response. Targeted mass spectrometry confirms that OSM-S-106 is a pro-inhibitor and that inhibition of PfAsnRS occurs via enzyme-mediated production of an Asn-OSM-S-106 adduct. Human AsnRS is much less susceptible to this reaction hijacking mechanism. X-ray crystallographic studies of human AsnRS in complex with inhibitor adducts and docking of pro-inhibitors into a model of Asn-tRNA-bound PfAsnRS provide insights into the structure-activity relationship and the selectivity mechanism.

BACKGROUND: Timely molecular surveillance of Plasmodium falciparum kelch 13 (k13) gene mutations is essential for monitoring the emergence and stemming the spread of artemisinin resistance. Widespread artemisinin resistance, as observed in Southeast Asia, would reverse significant gains that have been made against the malaria burden in Africa. The purpose of this study was to assess the prevalence of k13 polymorphisms in western Kenya and Ethiopia at sites representing varying transmission intensities between 2018 and 2022. METHODS: Dried blood spot samples collected through ongoing passive surveillance and malaria epidemiological studies, respectively, were investigated. The k13 gene was genotyped in P. falciparum isolates with high parasitaemia: 775 isolates from four sites in western Kenya (Homa Bay, Kakamega, Kisii, and Kombewa) and 319 isolates from five sites across Ethiopia (Arjo, Awash, Gambella, Dire Dawa, and Semera). DNA sequence variation and neutrality were analysed within each study site where mutant alleles were detected. RESULTS: Sixteen Kelch13 haplotypes were detected in this study. Prevalence of nonsynonymous k13 mutations was low in both western Kenya (25/783, 3.19%) and Ethiopia (5/319, 1.57%) across the study period. Two WHO-validated mutations were detected: A675V in three isolates from Kenya and R622I in four isolates from Ethiopia. Seventeen samples from Kenya carried synonymous mutations (2.17%). No synonymous mutations were detected in Ethiopia. Genetic variation analyses and tests of neutrality further suggest an excess of low frequency polymorphisms in each study site. Fu and Lis F test statistic in Semera was 0.48 (P > 0.05), suggesting potential population selection of R622I, which appeared at a relatively high frequency (3/22, 13.04%). CONCLUSIONS: This study presents an updated report on the low frequency of k13 mutations in western Kenya and Ethiopia. The WHO-validated R622I mutation, which has previously only been reported along the north-west border of Ethiopia, appeared in four isolates collected from eastern Ethiopia. The rapid expansion of R622I across Ethiopia signals the need for enhanced monitoring of the spread of drug-resistant P. falciparum parasites in East Africa. Although ACT remains currently efficacious in the study areas, continued surveillance is necessary to detect early indicators of artemisinin partial resistance.

Background: Nigeria has the highest malaria burden globally, and anti-malarials have been commonly used to treat malaria without parasitological confirmation. In 2012, Nigeria implemented rapid diagnostic tests (RDTs) to reduce the use of anti-malarials for those without malaria and to increase the use of artemisinin-based combination therapy (ACT) for malaria treatment. This study examined changes in anti-malarial receipt among children aged 6–59 months during a 12-year period of increasing RDT availability. Methods: A cross-sectional analysis was conducted using the Nigeria Malaria Indicator Survey (NMIS) data from 2010 (before RDT implementation in 2012), 2015, and 2021. The analysis assessed trends in prevalence of malaria by survey RDT result, and fever and anti-malarial/ACT receipt in the 2 weeks prior to the survey. A multivariable logistic regression was used to account for the complex survey design and to examine factors associated with anti-malarial receipt, stratified by survey RDT result, a proxy for recent/current malaria infection. Results: In a nationally-representative, weighted sample of 22,802 children aged 6–59 months, fever prevalence remained stable over time, while confirmed malaria prevalence decreased from 51.2% in 2010 to 44.3% in 2015 and 38.5% in 2021 (trend test p < 0.0001). Anti-malarial use among these children decreased from 19% in 2010 to 10% in 2021 (trend test p < 0.0001), accompanied by an increase in ACT use (2% in 2010 to 8% in 2021; trend test p < 0.0001). Overall, among children who had experienced fever, 30.6% of survey RDT-positive and 36.1% of survey RDT-negative children had received anti-malarials. The proportion of anti-malarials obtained from the private sector increased from 61.8% in 2010 to 80.1% in 2021 for RDT-positive children; most of the anti-malarials received in 2021 were artemisinin-based combinations. Factors associated with anti-malarial receipt for both RDT-positive and RDT-negative children included geographic region, greater household wealth, higher maternal education, and older children. Conclusion: From 2010 to 2021 in Nigeria, both malaria prevalence and anti-malarial treatments among children aged 6–59 months decreased, as RDT availability increased. Among children who had fever in the prior 2 weeks, anti-malarial receipt was similar between children with either positive or negative survey RDT results, indicative of persistent challenges in reducing inappropriate anti-malarials uptake. [ABSTRACT FROM AUTHOR]

Objective To investigate the risk of DM and evaluate the impact of SLE therapies on the risk of developing DM in patients with SLE. Methods Electronic database searches of PubMed, Embase, Cochrane Library and Web of Science were performed from inception to February 2023. Cohort and cross-sectional studies that analysed the risk of DM in patients with SLE were included. The associations between diabetes and antirheumatic agents, such as antimalarials and glucocorticoids, were analysed in cohort studies. Data were pooled using fixed- or random-effects meta-analysis to estimate pooled odd ratios (OR), relative risks (RR) and 95% confidence intervals (CIs). This study was registered with PROSPERO (CRD42023402774). Results A total of 37 studies (23 cross-sectional and 14 cohort studies) involving 266 537 patients with SLE were included. The pooled analyses from cross-sectional studies and cohort studies did not show an increased risk of DM in SLE patients (OR = 1.05, 95% CI 0.87–1.27; P  = 0.63 and RR = 1.32, 95% CI 0.93–1.87; P  = 0.12, respectively). However, several cohort studies consistently demonstrated a reduced risk of diabetes with antimalarials, while glucocorticoid use has been associated with an increased risk of developing diabetes. Age, sex, hypertension and immunosuppressants have not been identified as risk factors for DM in SLE patients. Conclusion Although there was no increased risk of DM in patients with SLE compared with controls, HCQ users or adherents had a decreased risk, whereas glucocorticoid users had an increased risk. [ABSTRACT FROM AUTHOR]

Objectives To evaluate the effect of antimalarial drugs in response to therapy, incidence of LN flares, and progression of kidney disease in a large LN cohort. Methods We retrospectively studied 424 biopsy-proven LN patients followed for >3 years. We obtained demographic, clinical, laboratory, histopathological and treatment variables. Antimalarial use was approached as (i) users vs no users, (ii) according to prevalent vs incident use regarding the LN flare and (iii) according to the type of antimalarial. All outcomes were evaluated by time-to-event analyses. Adjusted hazard ratios were obtained by Cox regression. Results The cohort included 424 patients, median age of 29 years (IQR 23–37), 96% female, with a median eGFR of 81 ml/min/1.73 m2 (IQR 48–118) and proteinuria of 3.4 g/g (IQR 1.9–5.5). Antimalarial use was associated with higher complete response (aHR 1.57, 1.08–2.27), lower incidence of kidney flares (aHR 0.63, 0.43–0.92) and lower progression to kidney failure (aHR 0.37, 0.23–0.53). The effect of antimalarials on these outcomes was modified by the presentation eGFR, histological class and/or concomitant initial immunosuppressor. These protective effects were observed in patients with prevalent or incident use regarding the LN flare and patients using hydroxychloroquine. The incidence of toxic retinopathy was 1.7%, 5.7% and 8.8% by 3, 5 and 7 years of continued antimalarial use, respectively. Conclusion The use of antimalarial drugs is associated with increased response to therapy, lower incidence of kidney flares, and lower progression to kidney failure in LN patients. Conversely, this population is at high risk of toxic maculopathy, and yearly ophthalmologic examination is recommended. [ABSTRACT FROM AUTHOR]

Introduction: Anesthesiologists play an important role in the management of labor and delivery during acute malaria infection. The peripartum anesthesia considerations for such cases remain unclear. Findings: Important peripartum considerations include the severity of thrombocytopenia and coagulopathy, hemodynamic status and cardiac disease, and the likelihood of central nervous system (CNS) involvement. Several antimalarial drugs may interact with perioperative medications, causing hypoglycemia, methemoglobinemia, or QT prolongation. Labor should usually not be induced. Patient volume status should be optimized pre-induction, but fluids should be administered with caution given the risk of cerebral edema. In case of CNS involvement intracranial pressure should be maintained. Case reports describe the successful use of neuraxial anesthesia but this approach requires further confirmation of safety. Despite the risks accompanying airway management in pregnancy, in some cases, general anesthesia was preferred due to the chance of CNS infection and disease complications. Tight postoperative assessments of neurological and bleeding status are indicated regardless of the mode of delivery. Conclusions: Despite the prevalence of malaria, the perioperative risk and preferred mode of anesthesia for pregnant patients with acute malaria remain under-researched and outcome data are limited. [ABSTRACT FROM AUTHOR]

Background Relapsing babesiosis often occurs in highly immunocompromised patients and has been attributed to the acquisition of resistance against drugs commonly used for treatment such as atovaquone, azithromycin, and clindamycin. Tafenoquine, which is approved for malaria prophylaxis and presumptive antirelapse treatment of Plasmodium vivax malaria, has shown activity against Babesia microti in several animal models of acute infection and in a single human case of relapsing babesiosis. Here, we report 5 cases of relapsing babesiosis treated with tafenoquine, including the previous case, and begin to define the conditions for optimal use of tafenoquine in relapsing babesiosis. Methods A definitive diagnosis of babesiosis was made by microscopic examination of Giemsa-stained thin blood smears or a real-time polymerase chain reaction (PCR) that targets the parasite 18S rRNA gene. Clearance of B. microti infection was ascertained by use of blood smear and real-time PCR. Results Tafenoquine was initiated with a loading dose of 600 mg. A weekly maintenance dose consisted of 200 mg or 300 mg; the lower dose was associated with a delayed clearance of B. microti. In 2 cases, all antimicrobial agents but tafenoquine were discontinued prior to clearance of infection. In 2 other cases, clearance was achieved while tafenoquine was administered along with other antimicrobial agents. In 3 of these 4 cases, tafenoquine was used in combination with atovaquone-proguanil. Other agents included atovaquone, azithromycin, and/or clindamycin. In 1 case, tafenoquine was administered alone and failed to prevent relapse. Conclusions Tafenoquine can be a useful adjunct for the treatment of highly immunocompromised patients experiencing relapsing babesiosis caused by B. microti. [ABSTRACT FROM AUTHOR]

Background: Malaria continues to wreak havoc on the well-being of the community. Resistant parasites are jeopardizing the treatment. This is a wake-up call for better medications. Folk plants are the key starting point for antimalarial drug discovery. After crushing and mixing the leaves of Coriandrum sativum with water, one cup of tea is drunk daily for a duration of three to five days as a remedy for malaria by local folks in Ethiopia. Additionally, in vitro experiments conducted on the plant leaf extract elsewhere have also demonstrated the plant's malaria parasite inhibitory effect. There has been no pharmacologic research to assert this endowment in animals, though. This experiment was aimed at evaluating the antimalarial efficacy of C. sativum in Plasmodium berghei infected mice. Methods: The plant's leaf was extracted using maceration with distilled water. The extract was examined for potential acute toxicity. An evaluation of secondary phytoconstituents was done. Standard antimalarial screening models (prophylactic, chemosuppressive, curative tests) were utilized to assess the antiplasmodial effect. In each test, thirty mice were organized into groups of five. To the three categories, the test substance was given at doses of 100, 200 and 400 mg/kg/day before or after the commencement of P. berghei infection. Positive and negative control mice were provided Chloroquine and distilled water, respectively. Rectal temperature, parasitemia, body weight, survival time and packed cell volume were ultimately assessed. Analysis of the data was performed using Statistical Package for Social Sciences. Results: No toxicity was manifested in mice. The extract demonstrated a significant inhibition of parasitemia (p < 0.05) in all the models. The inhibition of parasite load was highest with the upper dose in the suppressive test (82.74%) followed by the curative procedure (78.49%). Likewise, inhibition of hypothermia, weight loss hampering, improved survival and protection against hemolysis were elicited by the extract. Conclusions: The results of our experimental study revealed that the aqueous crude leaf extract of C. sativum exhibits significant antimalarial efficacy in multiple in vivo models involving mice infected with P. berghei. Given this promising therapeutic attribute, in depth investigation on the plant is recommended. [ABSTRACT FROM AUTHOR]

Malaria was a major cause of casualties during World War II in the Southwest Pacific, and drug supply issues were acute strategic concerns. The capture of the cinchona plantations of Indonesia by the Japanese Imperial Army and the lack of manufacturing capacity for synthetic substitutes were significant logistical constraints that limited Allied combat operations in the Indo-Pacific Region. Tens of thousands of soldiers were infected with malaria due to inadequate treatment and chemoprophylaxis. In Milne Bay, Papua New Guinea, military operations halted for several months at the end of 1942 due to poor malaria discipline compounded by inadequate medications. Sufficient drug supplies only became available in 1943 when daily quinacrine suppression was enforced. Drug supply disruptions during the COVID-19 pandemic are a reminder that specialist anti-infective medications could have an outsized, modern impact on military operations. [ABSTRACT FROM AUTHOR]

Fragment-based drug discovery (FBDD) focuses on small compounds, known as fragments, typically with a molecular weight of less than 300 Da. This study highlights the benefits of employing a pure natural product library for FBDD, contrasting with the predominant use of synthetic libraries. Practical methods for rapidly constructing such libraries from crude extracts were demonstrated across various plant and microbial samples. Twenty-nine (29) natural product fragments, including a new compound (20), were identified. Antimicrobial activities were assessed for a subset of the isolated compounds, revealing potent fragments (MICs 4–8 μg/mL) against Mycobacterium bovis bacille Calmette-Guérin (BCG), Staphylococcus aureus (SA), and methicillin-resistant S. aureus (MRSA). Furthermore, a native mass spectrometry technique was introduced to rapidly identify non-competitive fragments against malarial proteins. As a result, two pairs of non-competitive fragments, lepiotin C (31) and 7-amino deacetoxy cephalosporanic acid (32) binding to dynein light chain 1, methyl gallate (33) and β-santanin (34) binding to dUTPase, were identified, serving as promising starting points for developing potent malarial protein inhibitors. [ABSTRACT FROM AUTHOR]

Artemisia plants have traditional and ethnopharmacological uses in medicine, as well as in culinary items, seasonings, and drinks. Traditional medicine has used this genus as an antiinflammatory, anti-cancer, anti-malarial, antioxidant, and antiviral agent. All continents, except Antarctica, have seen its extensive spread. With this study, we want to compile all the available scientific information on the Artemisia genus, including its medicinal properties, chemical make-up, and distribution patterns. Using resources like Web of Science, Scopus, and PubMed/MEDLINE, we culled information from articles written on Artemisia plants. Information on phytochemicals and molecular pathways from preclinical pharmacological experiments was among the articles chosen for this revised review. Also, we looked at several old books and manuscripts. Artemisinin is a sesquiterpene lactone that can kill malaria parasites. Studies have also demonstrated the strong biological effects of other phytochemicals and essential oils from the Artemisia species. Artemisia absinthium L, one of the most well-known species of Artemisia, is the source of absinthe, a banned drink in most countries due to its neurotoxic effects. Research has shown that artemisia plants have several medicinal and traditional uses. Clinical and toxicological studies are the only ones that have provided any solid scientific evidence. As a result, these areas require further investigation in order to fully understand the molecular pharmacological process and therapeutic potential of this medicinal species. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Infants bear a significant malaria burden but are usually excluded from participating in early dose optimization studies that inform dosing regimens of antimalarial therapy. Unlike older children, infants' exclusion from early‐phase trials has resulted in limited evidence to guide accurate dosing of antimalarial treatment for uncomplicated malaria or malaria‐preventive treatment in this vulnerable population. Subsequently, doses used in infants are often extrapolated from older children or adults, with the potential for under‐ or overdosing. Population pharmacokinetic‐pharmacodynamic (PK‐PD) modelling, a quantitative methodology that applies mathematical and statistical techniques, can aid the design of clinical studies in infants that collect sparse pharmacokinetic data as well as support the analysis of such data to derive optimized antimalarial dosing in this complex and at‐risk yet understudied subpopulation. In this review, we reflect on what PK‐PD modelling can do in programmatic settings of most malaria‐endemic areas and how it can be used to inform antimalarial dose optimization for preventive and curative treatment of uncomplicated malaria in infants. We outline key developmental physiological changes that affect drug exposure in early life, the challenges of conducting dose optimization studies in infants, and examples of how PK‐PD modelling has previously informed antimalarial dose optimization in this subgroup. Additionally, we discuss the limitations and gaps of PK‐PD modelling when used for dose optimization in infants. To utilize modelling well, there is a need to generate useful, sparse, PK and PD data in this subpopulation to inform antimalarial optimal dosing in infancy. [ABSTRACT FROM AUTHOR]

Malaria has a wide impact on the healthcare system, affecting everyone from hyperendemic areas who dearth access to medical treatment to international tourists returning to nonendemic regions with tertiary referral care. Implementing timely and accurate diagnosis is necessary to stop malaria's growing global effect, which is attributed to the development of antimalarial medication resistance. In this research, potential antimalarial compounds, including quinine, primaquine, artemether, artelinic acid, triazoles‐modified, and so forth are examined with topological indices (TI) and linear regression modeling of said compounds. Some degree based topological indices are assembled for these drugs' chemical graphs. We compute the topological descriptors with the limiting behaviors associated with these pharmaceutical drugs. Moreover, in this study some of the physicochemical features of the drugs are estimated using these TIs in the QSPR models. These indices better reflect chemical properties such as boiling point, complexity, polarity, and so forth and the outcomes of regression technique acquired QSPR studies may aid in the creation of fresh medicines for the treatment of malaria. These indices and antimalarial activity were discovered to be related. Other compound series do very well with this relationship. The TIs could be a key component in creating and synthesizing new antimalarial drugs. [ABSTRACT FROM AUTHOR]

Despite continuous efforts to develop safer and efficient medications, malaria remains a major threat posing great challenges for new drug discovery. The emerging drug resistance, increased toxicities, and impoverished pharmacokinetic profiles exhibited by conventional drugs have hindered the search for new entities. Plasmepsins, a group of Plasmodium-specific, aspartic acid protease enzymes, are involved in many key aspects of parasite biology, and this makes them interesting targets for antimalarial chemotherapy. Among different isoforms, PlmIX serves as an unexplored antimalarial drug target that plays a crucial role along with PlmV and X in the parasite's survival by digesting hemoglobin in the host's erythrocytes. In this study, fragment-based virtual screening was performed by modeling the three-dimensional structure of PlmIX and predicting its ligand-binding pocket by using the Sitemap tool. Screening identified the fragments with the XP docking score ≤ -3 kcal/mol from the OTAVA General Fragment Library (≈16,397 fragments), and the selected fragments were chosen for ligand breeding. The resulting ligands (≈69,858 ligands) were subsequently subjected to filtering based on the QikProp properties along with carcinogenicity testing performed using CarcinoPred-EL and then docked in the SP (≈14,078 ligands) as well as XP mode (≈3,104 ligands), and compared with that of control ligands 49C and I0L. The top-ranked ligands were taken further for the calculation of the free energy of binding using Prime MM--GBSA. Overall, a total of six complexes were taken further for MD simulation studies performed at 100 ns to attain a better understanding of the binding mechanisms, and compounds 3 and 4 were found to be the most efficient ones in silico. The analysis of compound 3 revealed that the carbonyl group present in position 1 on the isoindoline moiety (Arg554) was responsible for inhibitory activity against PlmIX. However, the analysis of compound 4 revealed that the amide linkage sandwiched between the phenyl ring and isoquinoline moiety (Lys555 and Ser226) as well as carbonyl oxygen of the carbamoyl group present at position 2 of the pyrazole ring (Gln222) were responsible for PlmIX inhibitory activity, owing to their crucial interactions with key amino acid residues. [ABSTRACT FROM AUTHOR]

Background: The recommendation of universal diagnostic testing before malaria treatment aimed to address the problem of over-treatment with artemisinin-based combination therapy and the heightened risk of selection pressure and drug resistance and the use of malaria rapid diagnostic test (MRDT) was a key strategy, particularly among primary healthcare (PHC) workers whose access to and use of other forms of diagnostic testing were virtually absent. However, the use of MRDT can only remedy over-treatment when health workers respond appropriately to negative MRDT results by not prescribing anti-malarial drugs. This study assessed the use of MRDT and anti-malarial drug prescription practices, and the predictors, among PHC workers in Ebonyi state, Nigeria. Methods: We conducted an analytical cross-sectional questionnaire survey, among consenting PHC workers involved in the diagnosis and treatment of malaria, from January 15, 2020 to February 5, 2020. Data was collected via structured self-administered questionnaire and analysed using descriptive statistics and bivariate and multivariate generalized estimating equations. Results: Of the 490 participants surveyed: 81.4% usually/routinely used MRDT for malaria diagnosis and 18.6% usually used only clinical symptoms; 78.0% used MRDT for malaria diagnosis for all/most of their patients suspected of having malaria in the preceding month while 22.0% used MRDT for none/few/some; 74.9% had good anti-malarial drug prescription practice; and 68.0% reported appropriate response to negative MRDT results (never/rarely prescribed anti-malarial drugs for the patients) while 32.0% reported inappropriate response (sometimes/often/always prescribed anti-malarial drugs). The identified predictor(s): of the use of MRDT was working in health facilities supported by the United States' President's Malaria Initiative (PMI-supported health facilities); of good anti-malarial drug prescription practice were having good opinion about MRDT, having good knowledge about malaria diagnosis and MRDT, being a health attendant, working in PMI-supported health facilities, and increase in age; and of appropriate response to negative MRDT results was having good opinion about MRDT. Conclusions: The evidence indicate the need for, and highlight factors to be considered by, further policy actions and interventions for optimal use of MRDT and anti-malarial drug prescription practices among the PHC workers in Ebonyi state, Nigeria, and similar settings. [ABSTRACT FROM AUTHOR]

Xanthone and its derivatives are well known for their broad biological activities. This research aims to investigate the anticancer and antimalarial activities of synthesized xanthenol and xanthene compounds and to elucidate their mechanisms of action through molecular docking. The xanthenol compound was obtained through xanthone reduction with sodium triacetoxyborohydride, and xanthene synthesis was studied through three different reaction conditions: uncatalyzed and catalyzed by Lewis acid or Bronsted acid. The reduction reaction produced xanthenol in 30.50% yield, whereas the three reaction conditions produced xanthene and xanthone in 39.35-75.48% yield. An anticancer assay for Vero, WiDr, HeLa, and T47D cell lines was evaluated with a microculture tetrazolium assay, and an antimalarial activity test was examined using the heme polymerization inhibition method. The xanthene compound showed the lowest IC50 value (44 µg/mL) among the products in the T47D cell line. Meanwhile, the antimalarial assay showed that the xanthone compound could inhibit heme polymerization, with an IC50 value of 114 µg/mL. The molecular docking study revealed that the anticancer activity of xanthene occurred through the inhibition of the cyclooxygenase-2 (COX-2) enzyme, and the antimalarial activity of xanthone occurred through the inhibition of the Plasmodium falciparum lactate dehydrogenase enzyme. These results showed that xanthene and xanthone compounds are potential anticancer and antimalarial drugs, respectively. [ABSTRACT FROM AUTHOR]

Chisocheton is a large source of limonoids with various pharmacological effects, such as antiviral, antibacterial, antimalarial, antifungal, and cytotoxic activities. This study aimed to isolate, elucidate, and evaluate the cytotoxicity of limonoids from C. pentandrus stembarks. Isolation was carried out using various separation methods including extraction and column chromatography. Spectral data were analyzed by FT-IR, UV, DEPT 135°, ¹H, 13C-NMR, and HRTOF-MS and compared with those previously reported to determine the chemical structure. The obtained limonoids were lasiocarpine (1), lasiocarpine B (2), pentandricine (3), and 16β-hydroxydysobinin (4); all of which were successfully isolated from C. pentandrus for the first time. The cytotoxic activity of these limonoids were also evaluated against Michigan Cancer Foundation-7 (MCF-7) breast cancer cells using PrestoBlue method. Lasiocarpine A revealed the strongest cytotoxicity with an IC50 of 42.62 µM in moderate level. [ABSTRACT FROM AUTHOR]

Malaria impedes the ability of primary cells of the immune system to generate an efficacious inflammatory and immune response. Black seed (Nigella sativa) is a core dietary supplement and food additive in folklore. This study investigated the antioxidant, immunomodulatory, and anti-inflammatory effects of N. sativa cookies in Plasmodium berghei-infected mice. Aqueous extract of black seed was prepared, and the total phenol and flavonoid contents were determined. The mice were infected with standard inoculum of the strain NK65 P. berghei. The mice weight and behavioral changes were observed. The mice were fed with the N. sativa cookies (2.5%, 5%, and 10%) and 10 mg/kg chloroquine for 5 consecutive days after the infection was established. The reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase, catalase, and hematological parameters (red cell indices, leukocytes, and its differentials) in the infected mice were determined. The inflammatory mediators, C-reactive protein (CRP), and myeloperoxidase (MPO) were also assayed. The result revealed that black seed had a total phenol content of 18.73 mgGAE/g and total flavonoid content of 0.36 mgQUE/g. The infected mice treated with N. sativa cookies showed significantly decreased parasitaemia, MDA, and ROS levels. Furthermore, the results showed significant suppression in proinflammatory mediators (CRP and MPO) levels and enhanced antioxidant status of infected mice treated with N. sativa. The study suggests that N. sativa could function as nutraceuticals in the management of Plasmodium infection associated with inflammatory and immunomodulatory disorders. [ABSTRACT FROM AUTHOR]

Context: Malaria remains a significant global health challenge with emerging resistance to current treatments. Plasmodium falciparum glutathione reductase (PfGR) plays a critical role in the defense mechanisms of malaria parasites against oxidative stress. In this study, we investigate the potential of targeting PfGR with conventional antimalarials and dual drugs combining aminoquinoline derivatives with GR inhibitors, which reveal promising interactions between PfGR and studied drugs. The naphthoquinone Atovaquone demonstrated particularly high affinity and potential dual-mode binding with the enzyme active site and cavity. Furthermore, dual drugs exhibit enhanced binding affinity, suggesting their efficacy in inhibiting PfGR, where the aliphatic ester bond (linker) is essential for effective binding with the enzyme's active site. Overall, this research provides important insights into the interactions between antimalarial agents and PfGR and encourages further exploration of its role in the mechanisms of action of antimalarials, including dual drugs, to enhance antiparasitic efficacy. Methods: The drugs were tested as PfGR potential inhibitors via molecular docking on AutoDock 4, which was performed based on the preoptimized structures in HF/3-21G-PCM level of theory on ORCA 5. Drug-receptor systems with the most promising binding affinities were then studied with a molecular dynamic's simulation on AMBER 16. The molecular dynamics simulations were performed with a 100 ns NPT ensemble employing GAFF2 forcefield in the temperature of 310 K, integration time step of 2 fs, and non-bond cutoff distance of 6.0 Å. [ABSTRACT FROM AUTHOR]

Objectives Artemisinin-resistant Plasmodium falciparum malaria is currently spreading globally, including in Africa. Artemisinin resistance also leads to resistance to partner drugs used in artemisinin-based combination therapies. Sequencing of kelch13 , which is associated with artemisinin resistance, culture-based partner drug susceptibility tests, and ELISA-based growth measurement are conventionally used to monitor resistance; however, their application is challenging in resource-limited settings. Methods An experimental package for field studies with minimum human/material requirements was developed. Results First, qPCR-based SNP assay was applied in artemisinin resistance screening, which can detect mutations within 1 h and facilitate sample selection for subsequent processes. It had 100% sensitivity and specificity compared with DNA sequencing in the detection of the two common artemisinin resistance mutations in Uganda, C469Y and A675V. Moreover, in the partner drug susceptibility test, the cultured samples were dry-preserved on a 96-well filter paper plate and shipped to the central laboratory. Parasite growth was measured by ELISA using redissolved samples. It well reproduced the results of direct ELISA, reducing significant workload in the field (Pearson correlation coefficient: 0.984; 95% CI: 0.975–0.990). Conclusions Large-scale and sustainable monitoring is required urgently to track rapidly spreading drug-resistant malaria. In malaria-endemic areas, where research resources are often limited, simplicity and feasibility of the procedure is especially important. Our approach combines a qPCR-based rapid test, which is also applicable to point-of-care diagnosis of artemisinin resistance and centralized analysis of ex vivo culture. The approach could improve efficiency of field experiments and accelerate global drug resistance surveillance. [ABSTRACT FROM AUTHOR]

Background and objectives: This study validated the antimalarial efficacy of Laportea aestuans extract using chemosuppressive and curative models, identified its most active fraction, and performed chemical profiling of the active fraction. Methodology: The aerial part of L. aestuans (LA) was extracted with 80% methanol and assayed for its chemosuppressive and curative antimalarial activities through the oral administration of the extract (100, 200, 400 and 800 mg/kg) to groups consisting of five mice each. The extract was thereafter suspended in water and partitioned with dichloromethane to afford the dichloromethane (DLA) and aqueous (ALA) fractions. The fractions (10, 20, 40, and 80 mg/kg) were thereafter tested for their antimalarial activity followed by GC-MS analysis of the most active fraction. Results: The toxicity level was found to be above 2000 mg/kg. The activity recorded for the four-day chemosuppressive antimalarial tests showed a dose-dependent activity up to 400 mg/kg. The activity was significantly lower than that of chloroquine. The antimalarial activity of the extract at the lowest dose of 100 mg/kg was 42%. In the curative test, the extract of LA gave a dose-dependent activity that was significantly higher than the negative control. The DLA and ALA fractions gave a comparable curative activity across all doses. At 10 mg/kg, ALA and DLA gave percentage clearance of 81.25 ±1.84 and 87.45 ±1.35, respectively, which were significantly higher than that of the negative control (0.00 ±0.00) and significantly lower than that of the positive control (94.93 ±0.26). The chemical profiling revealed the presence of non-polar and medium-polar constituents in the dichloromethane fraction. Conclusion: The good antimalarial activity elicited by LA extractives supports its usage in ethnomedicine as an antimalarial agent. [ABSTRACT FROM AUTHOR]

Lanthanoid complexes have found potential application in diverse fields including biology and medicine. The present study aim to synthesize a new dione derivative of 1-phenylacetyl-pyrrolidine-2-carboxyaldehyde and its Lanthanoid complexes and investigate their antimicrobial and antimalarial activities. The ligand 1-phenylacetyl-pyrrolidine-2-carboxyaldehyde (L) and its Lanthanoid complexes; Ce(L)3](NO3)3.2H2O,[Pr(L)3](NO3)3.2H2O, and [Nd(L)3](NO3)3.2H2Owere synthesized and their structures elucidated by spectroscopic techniques, including ultraviolet-visible (UV-Vis), Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR) spectroscopy, magnetic susceptibility and elemental analysis.The antimicrobial activity of the ligand and its complexes was evaluated by the agar-well diffusion method. The antimalarial activity of Nd(III) complex was assessed using the Peter’s 4-day suppressive test in mice. Acute toxicity of Nd(III) complex was evaluated using the Lorke method. The synthesized compounds exhibited UV absorption between 282-380 nm. The FTIR spectra of the compounds showed absorption peaks for carbonyl (C=O) stretch at 1691-1703 cm-1. The ¹H-NMR for the ligand and its complexes appeared as multiplets between 7.29-7.50 ppm and their 13C-NMR spectra displayed signals between 127.07-135.40 ppm, and at 173 ppm attributed to the phenyl ring and the carbonyl carbons, respectively.The magnetic susceptibility results revealed the complexes were paramagnetic. Neodymium (III) complex ([Nd(L)3](NO3)3.2H2O) exhibited the most potent antimicrobial activity inhibiting more of the test organisms than its congeners.[Nd(L)3](NO3)3.2H2Oexhibited a dose-dependent antimalarial activity with a mild to moderate reduction in percentage parasitaemia. Acute toxicity test showed an LD50value of 2,154.07 mg/kg for [Nd(L)3](NO3)3.2H2O. The complex is relatively safe and has potential for use as antimicrobial and antimalarial agent. [ABSTRACT FROM AUTHOR]

Purpose: Artemisinin combination therapies, the first-line antimalarials in Nigeria, have reportedly suffered multiple failures in malaria treatment, hence the search for novel combination of other compounds. Methyl gallate and palmatine have been reported to exhibit antiplasmodial activities but the antimalarial activity of their combination has not been evaluated. Therefore, the evaluation of the combination of methyl gallate and palmatine for antimalarial activity in vitro and in vivo in the presence of piperine was carried out. Materials and Methods: The inhibitory potential of methyl gallate and palmatine combination on β-hematin (hemozoin) formation was studied in vitro. Also, the antimalarial activity of methyl gallate and palmatine combination with/without a bioenhancer (piperine) was evaluated in Plasmodium berghei NK65-infected mice. Results: Methyl gallate and palmatine in the ratio 3:2 acted synergistically in vitro and had the highest inhibitory effect (IC50 = 0.73 µg/mL) on β-hematin (hemozoin) formation. The 3:2 combination of methyl gallate and palmatine exhibited no antimalarial activity in vivo in the absence of piperine but caused reduction in parasitemia that exceeded 40% in the presence of piperine at the dose of 25 mg/kg body weight on days 6 and 8 post-inoculation in mice. Conclusion: The 3:2 combination of methyl gallate and palmatine in the presence of piperine exhibited antimalarial activity in vivo, possibly by synergistic inhibition of hemozoin formation which may cause accumulation of haem within the food vacuole of Plasmodium spp. and its death. [ABSTRACT FROM AUTHOR]

ImportanceMalaria is a devastating disease caused by Plasmodium parasites. The evolution of parasite drug resistance continues to hamper progress toward malaria elimination, and despite extensive efforts to control malaria, it remains a leading cause of death in Mozambique and other countries in the region. The development of successful vaccines and identification of molecular markers to track drug efficacy are essential for managing the disease burden. We present an analysis of the parasite genome in Mozambique, a country with one of the highest malaria burdens globally and limited available genomic data, revealing current selection pressure. We contribute additional evidence to limited prior studies supporting the effectiveness of SWGA in producing reliable genomic data from complex clinical samples. Our results provide the identity of genomic loci that may be associated with current antimalarial drug use, including artemisinin and lumefantrine, and reveal selection pressure predicted to compromise the efficacy of current vaccine candidates.

BACKGROUND: Despite scale-up of seasonal malaria chemoprevention (SMC) with sulfadoxine-pyrimethamine and amodiaquine (SP-AQ) in children 3-59 months of age in Burkina Faso, malaria incidence remains high, raising concerns regarding SMC effectiveness and selection of drug resistance. Using a case-control design, we determined associations between SMC drug levels, drug resistance markers, and presentation with malaria. METHODS: We enrolled 310 children presenting at health facilities in Bobo-Dioulasso. Cases were SMC-eligible children 6-59 months of age diagnosed with malaria. Two controls were enrolled per case: SMC-eligible children without malaria; and older (5-10 years old), SMC-ineligible children with malaria. We measured SP-AQ drug levels among SMC-eligible children and SP-AQ resistance markers among parasitemic children. Conditional logistic regression was used to compute odds ratios (ORs) comparing drug levels between cases and controls. RESULTS: Compared to SMC-eligible controls, children with malaria were less likely to have any detectable SP or AQ (OR, 0.33 [95% confidence interval, .16-.67]; P = .002) and have lower drug levels (P < .05). Prevalences of mutations mediating high-level SP resistance were rare (0%-1%) and similar between cases and SMC-ineligible controls (P > .05). CONCLUSIONS: Incident malaria among SMC-eligible children was likely due to suboptimal levels of SP-AQ, resulting from missed cycles rather than increased antimalarial resistance to SP-AQ.

INTRODUCTION: Screening for G6PD deficiency can inform disease management including malaria. Treatment with the antimalarial drugs primaquine and tafenoquine can be guided by point-of-care testing for G6PD deficiency. METHODS AND FINDINGS: Data from similar clinical studies evaluating the performance of the STANDARD G6PD Test (SD Biosensor, South Korea) conducted in Bangladesh, Brazil, Ethiopia, India, Thailand, the United Kingdom, and the United States were pooled. Test performance was assessed in a retrospective analysis on capillary and venous specimens. All study sites used spectrophotometry for reference G6PD testing, and either the HemoCue or complete blood count for reference hemoglobin measurement. The sensitivity of the STANDARD G6PD Test using the manufacturer thresholds for G6PD deficient and intermediate cases in capillary specimens from 4212 study participants was 100% (95% Confidence Interval (CI): 97.5%-100%) for G6PD deficient cases with 60% on the reference assay. The negative predictive value for females with G6PD activity >60% was 99.6% (95% CI 99.1%-99.8%) on capillary specimens. Sensitivity among 396 P. vivax malaria cases was 100% (69.2%-100.0%) for both deficient and intermediate cases. Across the full dataset, 37% of those classified as G6PD deficient or intermediate resulted from true normal cases. Despite this, over 95% of cases would receive correct treatment with primaquine, over 87% of cases would receive correct treatment with tafenoquine, and no true G6PD deficient cases would be treated inappropriately based on the result of the STANDARD G6PD Test. CONCLUSIONS: The STANDARD G6PD Test enables safe access to drugs which are contraindicated for individuals with G6PD deficiency. Operational considerations will inform test uptake in specific settings.

Recent antimalarial drug discovery has been a race to produce new medicines that overcome emerging drug resistance, whilst considering safety and improving dosing convenience. Discovery efforts have yielded a variety of new molecules, many with novel modes of action, and the most advanced are in late-stage clinical development. These discoveries have led to a deeper understanding of how antimalarial drugs act, the identification of a new generation of drug targets, and multiple structure-based chemistry initiatives. The limited pool of funding means it is vital to prioritize new drug candidates. They should exhibit high potency, a low propensity for resistance, a pharmacokinetic profile that favours infrequent dosing, low cost, preclinical results that demonstrate safety and tolerability in women and infants, and preferably the ability to block Plasmodium transmission to Anopheles mosquito vectors. In this Review, we describe the approaches that have been successful, progress in preclinical and clinical development, and existing challenges. We illustrate how antimalarial drug discovery can serve as a model for drug discovery in diseases of poverty.

Drug resistance remains a major obstacle to malaria control and eradication efforts, necessitating the development of novel therapeutic strategies to treat this disease. Drug combinations based on collateral sensitivity, wherein resistance to one drug causes increased sensitivity to the partner drug, have been proposed as an evolutionary strategy to suppress the emergence of resistance in pathogen populations. In this study, we explore collateral sensitivity between compounds targeting the Plasmodium dihydroorotate dehydrogenase (DHODH). We profiled the cross-resistance and collateral sensitivity phenotypes of several DHODH mutant lines to a diverse panel of DHODH inhibitors. We focus on one compound, TCMDC-125334, which was active against all mutant lines tested, including the DHODH C276Y line, which arose in selections with the clinical candidate DSM265. In six selections with TCMDC-125334, the most common mechanism of resistance to this compound was copy number variation of the dhodh locus, although we did identify one mutation, DHODH I263S, which conferred resistance to TCMDC-125334 but not DSM265. We found that selection of the DHODH C276Y mutant with TCMDC-125334 yielded additional genetic changes in the dhodh locus. These double mutant parasites exhibited decreased sensitivity to TCMDC-125334 and were highly resistant to DSM265. Finally, we tested whether collateral sensitivity could be exploited to suppress the emergence of resistance in the context of combination treatment by exposing wildtype parasites to both DSM265 and TCMDC-125334 simultaneously. This selected for parasites with a DHODH V532A mutation which were cross-resistant to both compounds and were as fit as the wildtype parent in vitro. The emergence of these cross-resistant, evolutionarily fit parasites highlights the mutational flexibility of the DHODH enzyme.

Abstract Introduction Anesthesiologists play an important role in the management of labor and delivery during acute malaria infection. The peripartum anesthesia considerations for such cases remain unclear. Findings Important peripartum considerations include the severity of thrombocytopenia and coagulopathy, hemodynamic status and cardiac disease, and the likelihood of central nervous system (CNS) involvement. Several antimalarial drugs may interact with perioperative medications, causing hypoglycemia, methemoglobinemia, or QT prolongation. Labor should usually not be induced. Patient volume status should be optimized pre-induction, but fluids should be administered with caution given the risk of cerebral edema. In case of CNS involvement intracranial pressure should be maintained. Case reports describe the successful use of neuraxial anesthesia but this approach requires further confirmation of safety. Despite the risks accompanying airway management in pregnancy, in some cases, general anesthesia was preferred due to the chance of CNS infection and disease complications. Tight postoperative assessments of neurological and bleeding status are indicated regardless of the mode of delivery. Conclusions Despite the prevalence of malaria, the perioperative risk and preferred mode of anesthesia for pregnant patients with acute malaria remain under-researched and outcome data are limited.

Mozambique is one of the four African countries which account for over half of all malaria deaths worldwide, yet little is known about the parasite genetic structure in that country. We performed P. falciparum amplicon and whole genome sequencing on 2251 malaria-infected blood samples collected in 2015 and 2018 in seven provinces of Mozambique to genotype antimalarial resistance markers and interrogate parasite population structure using genome-wide microhaplotyes. Here we show that the only resistance-associated markers observed at frequencies above 5% were pfmdr1-184F (59%), pfdhfr-51I/59 R/108 N (99%) and pfdhps-437G/540E (89%). The frequency of pfdhfr/pfdhps quintuple mutants associated with sulfadoxine-pyrimethamine resistance increased from 80% in 2015 to 89% in 2018 (p

Malaria is a life‐threatening disease that affects tropical and subtropical regions worldwide. Various drugs were used to treat malaria, including artemisinin and derivatives, antibiotics (tetracycline, doxycycline), quinolines (chloroquine, amodiaquine), and folate antagonists (sulfadoxine and pyrimethamine). Since the malarial parasites developed drug resistance, there is a need to develop new chemical entities with high efficacy and low toxicity. In this context, 1,2,4,5‐tetraoxanes emerged as an essential scaffold and have shown promising antimalarial activity. To improve activity and overcome resistance to various antimalarial drugs; 1,2,4,5‐tetraoxanes were fused with various aryl/heteroaryl/alicyclic/spiro moieties (steroid‐based 1,2,4,5‐tetraoxanes, triazine‐based 1,2,4,5‐tetraoxanes, aminoquinoline‐based 1,2,4,5‐tetraoxanes, dispiro‐based 1,2,4,5‐tetraoxanes, piperidine‐based 1,2,4,5‐tetraoxanes and diaryl‐based 1,2,4,5‐tetraoxanes). The present review aims to focus on covering the relevant literature published during the past 30 years (1992–2022). We summarize the most significant in vitro, in vivo results and structure–activity relationship studies of 1,2,4,5‐tetraoxane‐based hybrids as antimalarial agents. The structural evolution of different hybrids can provide the framework for the future development of 1,2,4,5‐tetraoxane‐based hybrids to treat malaria. [ABSTRACT FROM AUTHOR]

Abstract Background Drug repurposing offers a strategic alternative to the development of novel compounds, leveraging the known safety and pharmacokinetic profiles of medications, such as linezolid and levofloxacin for tuberculosis (TB). Anti-malarial drugs, including quinolones and artemisinins, are already applied to other diseases and infections and could be promising for TB treatment. Methods This review included studies on the activity of anti-malarial drugs, specifically quinolones and artemisinins, against Mycobacterium tuberculosis complex (MTC), summarizing results from in vitro, in vivo (animal models) studies, and clinical trials. Studies on drugs not primarily developed for TB (doxycycline, sulfonamides) and any novel developed compounds were excluded. Analysis focused on in vitro activity (minimal inhibitory concentrations), synergistic effects, pre-clinical activity, and clinical trials. Results Nineteen studies, including one ongoing Phase 1 clinical trial, were analysed: primarily investigating quinolones like mefloquine and chloroquine, and, to a lesser extent, artemisinins. In vitro findings revealed high MIC values for anti-malarials versus standard TB drugs, suggesting a limited activity. Synergistic effects with anti-TB drugs were modest, with some synergy observed in combinations with isoniazid or pyrazinamide. In vivo animal studies showed limited activity of anti-malarials against MTC, except for one study of the combination of chloroquine with isoniazid. Conclusions The repurposing of anti-malarials for TB treatment is limited by high MIC values, poor synergy, and minimal in vivo effects. Concerns about potential toxicity at effective dosages and the risk of antimicrobial resistance, especially where TB and malaria overlap, further question their repurposing. These findings suggest that focusing on novel compounds might be both more beneficial and rewarding.

We describe the efficient synthesis of novel dehydroxyquinines by arylation of quincorine bromide using Ni‐catalysed cross electrophile coupling. The method demonstrates robust compatibility with (hetero)aryl bromides bearing diverse functional groups. Oxidation at C‐9 of the dehydroxyquinines expediently provided quinine‐inspired pseudo‐natural products ('quinalogs'). Investigation of the compound collection against Plasmodium falciparum revealed a new insight into the structure activity relationship of quinine. Analogs bearing specifically functionalised pyridines, in place of the 6‐methoxyquinoline ring of quinine, retained activity at the same order of magnitude, albeit not exceeding the activity of the natural product. This synthetic strategy conveniently enables iteration of the aromatic component of quinine for the first time, and holds promise for the development of effective new antimalarials. [ABSTRACT FROM AUTHOR]

Background: Malaria treatment is faced with the challenge of access, affordability, availability, and quality of antimalarial medicines. Affordable medicines facility-malaria (AMFm) program and subsequently Co-payment mechanism were developed to help increase access to quality assured Artemisinin-based combination therapies (ACTs) in seven countries in sub-Saharan Africa. We explored through a qualitative study, experience of healthcare personnel on Co-payment mechanism and the implication on its use in private drug outlets in Uganda. Method: Private drug outlets that reported stocking antimalarial agents in moderate-to-high and low malaria transmission settings were purposively selected for inclusion in the study. In each drug outlet, data was collected from a pharmacist/dispenser through key informant interview. The interview was done using a key informant interview guide which covered the following areas, (i) sociodemographic characteristics, ii) awareness of healthcare personnel on the co-payment mechanism, (iii) awareness of healthcare personnel on quality assured artemisinin combination therapies (QAACT), (iv) antimalarial stocking in private drug outlets, (v) antimalarial dispensing prices, (vi) considerations made while stocking, and pricing antimalarial agents, vii) challenges in antimalarial dispensing, and (viii) access to antimalarial agents in private drug outlets. Data was managed using Atlas.ti and analyzed using framework methodology. Results: Data was collected from 25 key informants (12 pharmacists and 13 dispensers). Five themes emerged following data analysis, (i) antimalarial stocking influenced by price and client demand, (ii) access and purchasing behavior of drug outlet clients, (iii) basis of dispensing antimalarial agents in private drug outlets, (iv) awareness of QAACT, and (v) awareness of Co-payment mechanism. None of the study participants was aware of the existence of Co-payment mechanism and QAACT in the private sector. Duocotecin brand of ACTs was the most mentioned and dispensed ACT among the study participants in private drug outlets. Nearly all the pharmacists/dispensers said that many clients who request to purchase ACTs don't come with a prescription and prefer buying cheaper antimalarial agents. Study participants reported stocking and selling both ACTs and non-ACT antimalarial agents in the drug outlets. Pharmacists/dispensers in the drug outlets reported that most clients could not afford buying a full dose of an ACT. None of the study participants considered using Co-payment mechanism while stocking ACTs in the drug outlets. Conclusion: There is lack of awareness and utilization of Co-payment mechanism in stocking, pricing, and dispensing of ACTs among pharmacists/dispensers in private drug outlets in Uganda. The antimalarial dispensing in drug outlets was mostly based on prescriptions, clients' preferences, and medicine affordability. The Ministry of Health needs to create demand for Co-payment mechanism through public awareness campaigns, training of healthcare personnel and behavior change communication in the private sector. [ABSTRACT FROM AUTHOR]

Malaria remains an important and challenging infectious disease, and novel antimalarials are required. Benzyl isothiocyanate (BITC), the main breakdown product of benzyl glucosinolate, is present in all parts of Tropaeolum majus L. (T. majus) and has antibacterial and antiparasitic activities. To our knowledge, there is no information on the effects of BITC against malaria. The present study evaluates the antimalarial activity of aqueous extracts of BITC and T. majus seeds, leaves, and stems. We used flow cytometry to calculate the growth inhibition (GI) percentage of the extracts and BITC against unsynchronized cultures of the chloroquine-susceptible Plasmodium falciparum 3D7 − GFP strain. Extracts and/or compounds with at least 70% GI were validated by IC50 estimation against P. falciparum 3D7 − GFP and Dd2 (chloroquine-resistant strain) unsynchronized cultures by flow cytometry, and the resistance index (RI) was determined. T. majus aqueous extracts showed some antimalarial activity that was higher in seeds than in leaves or stems. BITC's GI was comparable to chloroquine's. BITC's IC50 was similar in both strains; thus, a cross-resistance absence with aminoquinolines was found (RI < 1). BITC presented features that could open new avenues for malaria drug discovery. [ABSTRACT FROM AUTHOR]

Objective Materials and Methods Results Conclusions To evaluate whether hydroxychloroquine (HCQ) or chloroquine (CQ) are effective for the treatment of oral lichen planus (OLP).A literature search was conducted in four databases. Clinical studies investigating the effect of HCQ/CQ in patients with OLP were included.Eleven studies were included. Four were RCTs and seven quasi‐experimental studies. The studies included 390 patients diagnosed with OLP, of which 326 and 7 received HCQ and CQ, respectively. 46 patients received topical dexamethasone, 5 placebo and 6 griseofulvin as controls. Five studies assessed pain, and all of them obtained pain reduction with the use of HCQ. Six studies reported objective clinical improvement of OLP with the use of HCQ. Five studies that used a subjective scale obtained that 24%–100% of the patients achieved a complete/almost complete improvement of OLP lesions and its symptomatology. The most frequent side effects were vision problems, gastric discomfort, rash, nauseas, headaches, skin pigmentation, and elevated kidney function. 17 patients had to withdraw from the studies.Current evidence is scarce to confirm HCQ as a therapeutic option for OLP. More RCTs are needed to compare its efficacy with topical corticosteroids and to evaluate whether HCQ reduces relapses of OLP. [ABSTRACT FROM AUTHOR]

Malaria and Human Immunodeficiency Virus infections are among the top 10 causes of death in low income countries. Furthermore, many medicines used in these treatment areas are substandard, which contributes to the high death rate. Using a monitoring system to identify substandard and falsified medicines, the study aims to evaluate the quality of antimalarial and antiretroviral medicines in Sahel countries, assessing site conditions, compliance of medicines with pharmacopoeia tests, formulation equivalence with a reference medicine, and the influence of climate on quality attributes. Ultra Performance Liquid Chromatography methods for eight active pharmaceutical ingredients were validated following the International Conference for Harmonization guideline for its detection and quantification. Quality control consists of visual inspections to detect any misinformation or imperfections and pharmacopeial testing to determine the quality of pharmaceutical products. Medicines which complied with uniformity dosage units and dissolution tests were stored under accelerated conditions for 6 months. Artemether/Lumefantrine and Lopinavir/Ritonavir formulations failed uniformity dosage units and disintegration tests respectively, detecting a total of 28.6% substandard medicines. After 6 months stored under accelerated conditions (40 °C // 75% relative humidity) simulating climatic conditions in Sahel countries, some medicines failed pharmacopeia tests. It demonstrated the influence of these two factors in their quality attributes. This study emphasizes the need of certified quality control laboratories as well as the need for regulatory systems to maintain standards in pharmaceutical manufacturing and distribution in these countries, especially when medicines are transported to rural areas where these climatic conditions are harsher. [ABSTRACT FROM AUTHOR]

Background: Healthcare costs are a major burden on the society of developing countries like India. Countries like India try to limit healthcare costs in support of generic medicine. So, the Indian government initiated the Jan Aushadhi scheme in 2008 to provide high-quality generic medication at a low cost. Aim: The aim of the study was to compare the cost difference between Jan Aushadhi generic pharmaceutical formulations and branded medications in Tamil Nadu. Settings and Design: Pharmaco economic - Cost minimization observational study. Methods and Material: Study Duration: Five months, from February 2023 to June 2023. Study Place: 10 Jan Aushadhi outlets from various districts of Tamil Nadu. Sampling technique: Convenience sampling technique Statistical analysis used: Mean median, mode and Percentage. Results: A total of 729 medications were available in 10 Jan Aushadhi outlets. The Jan Aushadhi outlet has the most cardiovascular medications and the fewest antimalarial medications among different categories of drugs. Erythropoietin has the biggest cost difference between the average cost of branded medications and Jan Aushadhi drug costs, while Digoxin has the lowest cost difference. Antitubercular drugs, Oxytocics, Antileprosy drugs, Antiparkinsonism categories of drugs also delisted in Jan Aushadhi outlet. Conclusions: Compared to branded drugs, Jan Aushadhi's generic drugs are 64.65 % less costly on an average as observed in our study. The manufacturer of Jan Aushadhi shops is a WHO and GMO-certified company, and they manufacture branded drugs. So, there will be no quality compromise in Jan Aushadhi's generic drugs. [ABSTRACT FROM AUTHOR]

Antimalarial drugs have been used over the years to control the impact of malaria infection. They sometimes suffer from inefficacy, suboptimal dose administration, and/or parasite resistance. Monitoring antimalarial drug concentrations and their metabolites in biological matrices becomes imperative to elucidate any case of inefficacy, inadequate drug concentration, suboptimal dose, or drug-resistant parasites. The present study conducted a critical assessment and comparison of trends and bioanalytical methods used for estimating the pharmacokinetic profiles of antimalarial drugs used in Africa between 1985 and 2021. Findings indicated random procedural inadequacies, inconsistencies, poor compliance to standards and protocols and poor documentation approaches, all of which were capable of resulting in false or misleading interpretations of results. Suggestions on how to improve method performance, why and how to select a particular method for a specific matrix, results reporting and other important standard procedural ethics on the subject are highlighted. Africans and Africa as a continent must step up and intensify research efforts that capture and accommodate African peculiarities and economic well-being. This review presents the current state of the bioanalytical approaches to antimalarial drugs and calls for an adjustment to tackle antimalarial drug treatment failure ab initio. [ABSTRACT FROM AUTHOR]