Artemisinin derivatives for treating severe malaria

Safety and efficacy of artesunate treatment in severely injured patients with traumatic hemorrhage. The TOP-ART randomized clinical trial

PURPOSE

This study aimed at determining whether intravenous artesunate is safe and effective in reducing multiple organ dysfunction syndrome in trauma patients with major hemorrhage.

METHODS

TOP-ART, a randomized, blinded, placebo-controlled, phase IIa trial, was conducted at a London major trauma center in adult trauma patients who activated the major hemorrhage protocol. Participants received artesunate or placebo (2:1 randomization ratio) as an intravenous bolus dose (2.4 mg/kg or 4.8 mg/kg) within 4 h of injury. The safety outcome was the 28-day serious adverse event (SAE) rate. The primary efficacy outcome was the 48 h sequential organ failure assessment (SOFA) score. The per-protocol recruitment target was 105 patients.

RESULTS

The trial was terminated after enrolment of 90 patients because of safety concerns. Eighty-three participants received artesunate (n = 54) or placebo (n = 29) and formed the safety population and 75 met per-protocol criteria (48 artesunate, 27 placebo). Admission characteristics were similar between groups (overall 88% male, median age 29 years, median injury severity score 22), except participants who received artesunate were more shocked (median base deficit 9 vs. 4.7, p = 0.042). SAEs occurred in 17 artesunate participants (31%) vs. 5 who received placebo (17%). Venous thromboembolic events (VTE) occurred in 9 artesunate participants (17%) vs. 1 who received placebo (3%). Superiority of artesunate was not supported by the 48 h SOFA score (median 5.5 artesunate vs. 4 placebo, p = 0.303) or any of the trial's secondary endpoints.

CONCLUSION

Among critically ill trauma patients, artesunate is unlikely to improve organ dysfunction and might be associated with a higher VTE rate.

Aqueous Extract of Artemisia annua Shows In Vitro Antimicrobial Activity and an In Vivo Chemopreventive Effect in a Small-Cell Lung Cancer Model

Artemisia annua (A. annua) has been used as a medicinal plant in the treatment of several infectious and non-infectious diseases in the forms of tea and press juice since ancient times. The aim of this study was to evaluate the aqueous extract of A. annua (AAE) as an antimicrobial agent in vitro and to evaluate its chemopreventive efficacy in vivo in a small-cell lung cancer (SCLC) animal model. The dried powder of AAE was prepared using the Soxhlet extraction system from the leaves of Artemisia annua. The in vitro activity of AAE was determined against Candida albicans (C. albicans), Enterococcus faecalis (E. faecalis), Klebsiella pneumoniae (K. pneumoniae), and methicillin-resistant Staphylococcus aureus (MRSA) using the agar well diffusion method and propidium iodide (PI)-stained microbial death under a confocal microscope. The pretreatment of mice with AAE was initiated two weeks before the first dose of benzo[a]pyrene and continued for 21 weeks. The chemopreventive potential of the extract was evaluated by flow cytometry and biochemical and histopathological analyses of the tissues and serum accordingly, after sacrificing the mice. The data revealed the antimicrobial potential of AAE against all the species investigated, as it showed growth-inhibitory activity by MIC, as well as confocal microscopy. The pretreatment of AAE exhibited significant protection in carcinogen-modulated, average body weight (ABW), and relative organ weight (ROW) cancer biomarkers in the serum and antioxidants in the lungs. The hematoxylin and eosin (H&E) staining of the tissues revealed that AAE prevented malignancy in the lungs. AAE also induced apoptosis and decreased intracellular reactive oxygen species (ROS) in the lung cells analyzed by flow cytometry. The current findings demonstrated the use of AAE as an alternative medicine in the treatment of infectious disease and the chemoprevention of lung cancer. To our knowledge, this is the first study that summarizes the chemopreventive potential of AAE in a lung cancer model in vivo. However, further investigations are suggested to understand the role of AAE to potentiate the therapeutic index of the commercially available drugs that show multiple drug resistance against microbial growth and high toxicity during cancer chemotherapy.

Potential Emergence of Plasmodium Resistance to Artemisinin Induced by the Use of Artemisia annua for Malaria and COVID-19 Prevention in Sub-African Region

Plasmodium resistance to antimalarial drugs is an obstacle to the elimination of malaria in endemic areas. This situation is particularly dramatic for Africa, which accounts for nearly 92% of malaria cases worldwide. Drug pressure has been identified as a key factor in the emergence of antimalarial drug resistance. Indeed, this pressure is favoured by several factors, including the use of counterfeit forms of antimalarials, inadequate prescription controls, poor adherence to treatment regimens, dosing errors, and the increasing use of other forms of unapproved antimalarials. This resistance has led to the replacement of chloroquine (CQ) by artemisinin-based combination therapies (ACTs) which are likely to become ineffective in the coming years due to the uncontrolled use of Artemisia annua in the sub-Saharan African region for malaria prevention and COVID-19. The use of Artemisia annua for the prevention of malaria and COVID-19 could be an important factor in the emergence of resistance to Artemisinin-based combination therapies.

NADPH Oxidase: a Possible Therapeutic Target for Cognitive Impairment in Experimental Cerebral Malaria

Long-term cognitive impairment associated with seizure-induced hippocampal damage is the key feature of cerebral malaria (CM) pathogenesis. One-fourth of child survivors of CM suffer from long-lasting neurological deficits and behavioral anomalies. However, mechanisms on hippocampal dysfunction are unclear. In this study, we elucidated whether gp91^phox isoform of nicotinamide adenine dinucleotide phosphate oxidase 2 (NOX2) (a potent marker of oxidative stress) mediates hippocampal neuronal abnormalities and cognitive dysfunction in experimental CM (ECM). Mice symptomatic to CM were rescue treated with artemether monotherapy (ARM) and in combination with apocynin (ARM + APO) adjunctive based on scores of Rapid Murine Come behavior Scale (RMCBS). After a 30-day survivability period, we performed Barnes maze, T-maze, and novel object recognition cognitive tests to evaluate working and reference memory in all the experimental groups except CM. Sensorimotor tests were conducted in all the cohorts to assess motor coordination. We performed Golgi-Cox staining to illustrate cornu ammonis-1 (CA1) pyramidal neuronal morphology and study overall hippocampal neuronal density changes. Further, expression of NOX2, NeuN (neuronal marker) in hippocampal CA1 and dentate gyrus was determined using double immunofluorescence experiments in all the experimental groups. Mice administered with ARM monotherapy and APO adjunctive treatment exhibited similar survivability. The latter showed better locomotor and cognitive functions, reduced ROS levels, and hippocampal NOX2 immunoreactivity in ECM. Our results show a substantial increase in hippocampal NeuN immunoreactivity and dendritic arborization in ARM + APO cohorts compared to ARM-treated brain samples. Overall, our study suggests that overexpression of NOX2 could result in loss of hippocampal neuronal density and dendritic spines of CA1 neurons affecting the spatial working and reference memory during ECM. Notably, ARM + APO adjunctive therapy reversed the altered neuronal morphology and oxidative damage in hippocampal neurons restoring long-term cognitive functions after CM.

Antiprotozoal and Antitumor Activity of Natural Polycyclic Endoperoxides: Origin, Structures and Biological Activity

Polycyclic endoperoxides are rare natural metabolites found and isolated in plants, fungi, and marine invertebrates. The purpose of this review is a comparative analysis of the pharmacological potential of these natural products. According to PASS (Prediction of Activity Spectra for Substances) estimates, they are more likely to exhibit antiprotozoal and antitumor properties. Some of them are now widely used in clinical medicine. All polycyclic endoperoxides presented in this article demonstrate antiprotozoal activity and can be divided into three groups. The third group includes endoperoxides, which show weak antiprotozoal activity with a reliability of up to 70%, and this group includes only 1.1% of metabolites. The second group includes the largest number of endoperoxides, which are 65% and show average antiprotozoal activity with a confidence level of 70 to 90%. Lastly, the third group includes endoperoxides, which are 33.9% and show strong antiprotozoal activity with a confidence level of 90 to 99.6%. Interestingly, artemisinin and its analogs show strong antiprotozoal activity with 79 to 99.6% confidence against obligate intracellular parasites which belong to the genera Plasmodium, Toxoplasma, Leishmania, and Coccidia. In addition to antiprotozoal activities, polycyclic endoperoxides show antitumor activity in the proportion: 4.6% show weak activity with a reliability of up to 70%, 65.6% show an average activity with a reliability of 70 to 90%, and 29.8% show strong activity with a reliability of 90 to 98.3%. It should also be noted that some polycyclic endoperoxides, in addition to antiprotozoal and antitumor properties, show other strong activities with a confidence level of 90 to 97%. These include antifungal activity against the genera Aspergillus, Candida, and Cryptococcus, as well as anti-inflammatory activity. This review provides insights on further utilization of polycyclic endoperoxides by medicinal chemists, pharmacologists, and the pharmaceutical industry.

Artemether for severe malaria

BACKGROUND

In 2011 the World Health Organization (WHO) recommended parenteral artesunate in preference to quinine as first-line treatment for people with severe malaria. Prior to this recommendation many countries, particularly in Africa, had begun to use artemether, an alternative artemisinin derivative. This Cochrane Review evaluates intramuscular artemether compared with both quinine and artesunate.

OBJECTIVES

To assess the efficacy and safety of intramuscular artemether versus any other parenteral medication in the treatment of severe malaria in adults and children.

SEARCH METHODS

We searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (the Cochrane Library), MEDLINE, Embase, and LILACS, ISI Web of Science, conference proceedings, and reference lists of articles. We also searched the WHO International Clinical Trial Registry Platform, ClinicalTrials.gov, and the metaRegister of Controlled Trials (mRCT) for ongoing trials up to 7 September 2018. We checked the reference lists of all studies identified by the search. We examined references listed in review articles and previously compiled bibliographies to look for eligible studies.

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing intramuscular artemether with intravenous/intramuscular quinine or artesunate for treating severe malaria.

DATA COLLECTION AND ANALYSIS

The primary outcome was all-cause death. Two review authors independently screened each article by title and abstract, and examined potentially relevant studies for inclusion using an eligibility form. Two review authors independently extracted data and assessed risk of bias of included studies. We summarized dichotomous outcomes using risk ratios (RRs) and continuous outcomes using mean differences (MDs), and have presented both measures with 95% confidence intervals (CIs). Where appropriate, we combined data in meta-analyses and used the GRADE approach to summarize the certainty of the evidence.

MAIN RESULTS

We included 19 RCTs, enrolling 2874 adults and children with severe malaria, carried out in Africa (12 trials) and in Asia (7 trials).Artemether versus quinineFor children, there is probably little or no difference in the risk of death between intramuscular artemether and quinine (RR 0.97, 95% CI 0.77 to 1.21; 13 trials, 1659 participants, moderate-certainty evidence). Coma resolution time may be about five hours shorter with artemether (MD -5.45, 95% CI -7.90 to -3.00; six trials, 358 participants, low-certainty evidence). Artemether may make little difference to neurological sequelae (RR 0.84, 95% CI 0.66 to 1.07; seven trials, 968 participants, low-certainty evidence). Compared to quinine, artemether probably shortens the parasite clearance time by about nine hours (MD -9.03, 95% CI -11.43 to -6.63; seven trials, 420 participants, moderate-certainty evidence), and may shorten the fever clearance time by about three hours (MD -3.73, 95% CI -6.55 to -0.92; eight trials, 457 participants, low-certainty evidence).For adults, treatment with intramuscular artemether probably results in fewer deaths than treatment with quinine (RR 0.59, 95% CI 0.42 to 0.83; four trials, 716 participants, moderate-certainty evidence).Artemether versus artesunateArtemether and artesunate have not been directly compared in randomized trials in children.For adults, mortality is probably higher with intramuscular artemether (RR 1.80, 95% CI 1.09 to 2.97; two trials, 494 participants, moderate-certainty evidence).

AUTHORS' CONCLUSIONS

Artemether appears to be more effective than quinine in children and adults. Artemether compared to artesunate has not been extensively studied, but in adults it appears inferior. These findings are consistent with the WHO recommendations that artesunate is the drug of choice, but artemether is acceptable when artesunate is not available.

PZQ Therapy: How Close are we in the Development of Effective Alternative Anti-schistosomal Drugs?

Today schistosomiasis, caused mainly by the three major schistosome species (S. mansoni, S. haematobium and S. japonicum), has for many decades and still continues to be on a rapid and swift rise globally, claiming thousands of lives every year and leaving 800 million people at the risk of infection. Due to the high prevalence of this disease and the steady increase in the infection rates, praziquantel (PZQ) remains the only effective drug against this acute disease although it has no effect on the juvenile schistosome parasite. However, no significant approaches have been made in recent years in the discovery of new or alternative drugs and unfortunately, resistance to this drug has been reported in some parts of the world. Therefore, it is imperative to develop a new drug for this debilitating disease. In this review, a brief history of past, present, and new promising anti-schistosomal drugs is presented.

Artemether-lumefantrine and liver enzyme abnormalities in non-severe Plasmodium falciparum malaria in returned travellers: a retrospective comparative study with quinine-doxycycline in a Portuguese centre

Background

Artemisinin-based therapy is the current standard treatment for non-severe malaria due to Plasmodium falciparum. The potential for asymptomatic liver toxicity of this therapy and its implication in clinical practice is currently unknown. The aim of this study is to assess the hepatic function in patients treated with a standard three-day artemisinin-based regimen and to compare it with the quinine-doxycycline regimen.

Methods

Retrospective and comparative study of returned adult travellers admitted with non-severe P. falciparum malaria. Fifty-seven patients were included: 19 treated with artemisinin-based therapy and 38 with quinine-doxycycline therapy.

Results

During treatment, when compared with quinine-doxycycline group, the artemisinin-lumefantrine group presented a higher proportion of significant liver enzyme abnormalities (42 vs. 5%, p < 0.01) and a higher peak value of aspartate aminotransferase (131 vs. 64 U/L, p < 0.01) and alanine aminotransferase (99 vs. 75 U/L, p = 0.05). None of the patients was symptomatic, there were no treatment interruptions and all patients achieved clinical cure.

Conclusions

Treatment of uncomplicated falciparum malaria with artemisinin-based therapy might cause asymptomatic liver enzyme abnormalities in the first days of treatment. Nevertheless, these liver enzyme abnormalities seem to be harmless, asymptomatic and self-limited.

Honoring antiparasitics: The 2015 Nobel Prize in Physiology or Medicine

Protozoa and helminths are the two main groups that cause parasitic diseases with a broad spectrum of clinical symptoms. Protozoa are unicellular organisms like the malaria parasite Plasmodium, which is responsible for the majority of deaths associated with parasitic infections. Helminths are alternative parasites that can produce debilitating diseases in hosts, some of which result in chronic infections. The discovery of effective therapeutic drugs is the key to improving health in regions of poverty and poor sanitation where these parasites usually occur. It is very encouraging that the 2015 Nobel Prize in Physiology or Medicine was awarded to Youyou Tu as well as William C. Campbell and Satoshi Õmura for their considerable contributions in discovering artemisinin and avermectin, respectively. Both drugs revolutionized therapies for filariasis and malaria, significantly reducing by large percentages their morbidity and mortality.

Efficacy of a novel sublingual spray formulation of artemether in African children with Plasmodium falciparum malaria

The efficacy of sublingual artemether (ArTiMist) was investigated in two studies. In study 1, 31 children were randomized to sublingual artemether (n = 16) or intravenous (i.v.) quinine (n = 15). In study 2, 151 children were randomized to sublingual artemether (n = 77) or i.v. quinine (n = 74). For both studies, patients weighed between 5 and 15 kg and had either severe or complicated malaria based on WHO criteria, or they had uncomplicated malaria but were unable to tolerate oral medication as a result of nausea, vomiting, or diarrhea. Patients received either 3 mg/kg of body weight of sublingual artemether or a loading dose of 20 mg/kg of i.v. quinine followed by 10 mg/kg every 8 h i.v. thereafter. The primary endpoint was parasitological success, defined as a reduction in parasite count of ≥90% of that at baseline at 24 h after the first dose. Other endpoints based on parasite clearance and clinical response were evaluated. In study 1, there were parasitological success rates of 93.3% (14/15) and 66.7% (10/15) for the sublingual artemether and quinine treatments, respectively. In study 2, 94.3% (66/70) of the ArTiMist-treated patients and 39.4% (28/71) of the quinine-treated patients had parasitological success (P < 0.0001). Indicators of parasite clearance (parasite clearance time [PCT], time for parasite count to fall by 50% [PCT50], time for parasite count to fall by 90% [PCT90], and percent reduction in parasitemia from baseline at 24 h [PRR24]) were significantly superior for children treated with sublingual artemether compared to those treated with i.v. quinine. There were no differences between treatments for the clinical endpoints, such as fever clearance time. The local tolerability of sublingual artemether was good. Sublingual artemether leads to rapid parasite clearance and clinical recovery. (Studies 1 and 2 are registered at ClinicalTrials.gov under registration numbers NCT01047436 and NCT01258049, respectively.).

Dried-leaf Artemisia annua: A practical malaria therapeutic for developing countries?

Artemisinin from the plant Artemisia annua (A. annua) L., and used as artemisinin combination therapy (ACT), is the current best therapeutic for treating malaria, a disease that hits children and adults especially in developing countries. Traditionally, A. annua was used by the Chinese as a tea to treat “fever”. More recently, investigators have shown that tea infusions and oral consumption of the dried leaves of the plant have prophylactic and therapeutic efficacy. The presence of a complex matrix of chemicals within the leaves seems to enhance both the bioavailability and efficacy of artemisinin. Although about 1000-fold less potent than artemisinin in their antiplasmodial activity, these plant chemicals are mainly small molecules that include other artemisinic compounds, terpenes (mainly mono and sesqui), flavonoids, and polyphenolic acids. In addition, polysaccharide constituents of A. annua may enhance bioavailability of artemisinin. Rodent pharmacokinetics showed longer T_½ and T_max and greater C_max and AUC in Plasmodium chabaudi-infected mice treated with A. annua dried leaves than in healthy mice. Pharmacokinetics of deoxyartemisinin, a liver metabolite of artemisinin, was more inhibited in infected than in healthy mice. In healthy mice, artemisinin serum levels were > 40-fold greater in dried leaf fed mice than those fed with pure artemisinin. Human trial data showed that when delivered as dried leaves, 40-fold less artemisinin was required to obtain a therapeutic response compared to pure artemisinin. ACTs are still unaffordable for many malaria patients, and cost estimates for A. annua dried leaf tablet production are orders of magnitude less than for ACT, despite improvements in the production capacity. Considering that for > 2000 years this plant was used in traditional Chinese medicine for treatment of fever with no apparent appearance of artemisinin drug resistance, the evidence argues for inclusion of affordable A. annua dried leaf tablets into the arsenal of drugs to combat malaria and other artemisinin-susceptible diseases.

Artemether for severe malaria

BACKGROUND

In 2011 the World Health Organization (WHO) recommended parenteral artesunate in preference to quinine as first-line treatment for people with severe malaria. Prior to this recommendation, many countries, particularly in Africa, had begun to use artemether, an alternative artemisinin derivative. This review evaluates intramuscular artemether compared with both quinine and artesunate.

OBJECTIVES

To assess the efficacy and safety of intramuscular artemether versus any other parenteral medication in treating severe malaria in adults and children.

SEARCH METHODS

We searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (The Cochrane Library), MEDLINE, EMBASE and LILACS, ISI Web of Science, conference proceedings and reference lists of articles. We also searched the WHO clinical trial registry platform, ClinicalTrials.gov and the metaRegister of Controlled Trials (mRCT) for ongoing trials up to 9 April 2014.

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing intramuscular artemether with intravenous or intramuscular antimalarial for treating severe malaria.

DATA COLLECTION AND ANALYSIS

The primary outcome was all-cause death.Two authors independently assessed trial eligibility, risk of bias and extracted data. We summarized dichotomous outcomes using risk ratios (RR) and continuous outcomes using mean differences (MD), and presented both measures with 95% confidence intervals (CI). Where appropriate, we combined data in meta-analyses and assessed the quality of the evidence using the GRADE approach.

MAIN RESULTS

We included 18 RCTs, enrolling 2662 adults and children with severe malaria, carried out in Africa (11) and in Asia (7). Artemether versus quinine For children in Africa, there is probably little or no difference in the risk of death between intramuscular artemether and quinine (RR 0.96, 95% CI 0.76 to 1.20; 12 trials, 1447 participants, moderate quality evidence). Coma recovery may be about five hours shorter with artemether (MD -5.45, 95% CI -7.90 to -3.00; six trials, 358 participants, low quality evidence), and artemether may result in fewer neurological sequelae, but larger trials would be needed to confirm this (RR 0.84, 95% CI 0.66 to 1.07; seven trials, 968 participants, low quality evidence). Artemether probably shortens the parasite clearance time by about nine hours (MD -9.03, 95% CI -11.43 to -6.63; seven trials, 420 participants, moderate quality evidence), and may shorten the fever clearance time by about three hours (MD -3.73, 95% CI -6.55 to -0.92; eight trials, 457 participants, low quality evidence).For adults in Asia, treatment with intramuscular artemether probably results in fewer deaths than treatment with quinine (RR 0.59, 95% CI 0.42 to 0.83; four trials, 716 participants, moderate quality evidence). Artemether versus artesunate Artemether and artesunate have not been directly compared in randomized trials in African children.For adults in Asia, mortality is probably higher with intramuscular artemether (RR 1.80, 95% CI 1.09 to 2.97, two trials,494 participants, moderate quality evidence).

AUTHORS' CONCLUSIONS

Although there is a lack of direct evidence comparing artemether with artesunate, artemether is probably less effective than artesunate at preventing deaths from severe malaria. In circumstances where artesunate is not available, artemether is an alternative to quinine.

Fatty acid synthesis and pyruvate metabolism pathways remain active in dihydroartemisinin-induced dormant ring stages of Plasmodium falciparum

Artemisinin (ART)-based combination therapy (ACT) is used as the first-line treatment of uncomplicated falciparum malaria worldwide. However, despite high potency and rapid action, there is a high rate of recrudescence associated with ART monotherapy or ACT long before the recent emergence of ART resistance. ART-induced ring-stage dormancy and recovery have been implicated as possible causes of recrudescence; however, little is known about the characteristics of dormant parasites, including whether dormant parasites are metabolically active. We investigated the transcription of 12 genes encoding key enzymes in various metabolic pathways in P. falciparum during dihydroartemisinin (DHA)-induced dormancy and recovery. Transcription analysis showed an immediate downregulation for 10 genes following exposure to DHA but continued transcription of 2 genes encoding apicoplast and mitochondrial proteins. Transcription of several additional genes encoding apicoplast and mitochondrial proteins, particularly of genes encoding enzymes in pyruvate metabolism and fatty acid synthesis pathways, was also maintained. Additions of inhibitors for biotin acetyl-coenzyme A (CoA) carboxylase and enoyl-acyl carrier reductase of the fatty acid synthesis pathways delayed the recovery of dormant parasites by 6 and 4 days, respectively, following DHA treatment. Our results demonstrate that most metabolic pathways are downregulated in DHA-induced dormant parasites. In contrast, fatty acid and pyruvate metabolic pathways remain active. These findings highlight new targets to interrupt recovery of parasites from ART-induced dormancy and to reduce the rate of recrudescence following ART treatment.

Infectious causes of stroke

Most infectious pathogens have anecdotal evidence to support a link with stroke, but certain pathogens have more robust associations, in which causation is probable. Few dedicated prospective studies of stroke in the setting of infection have been done. The use of head imaging, a clinical standard of diagnostic care, to confirm stroke and stroke type is not universal. Data for stroke are scarce in locations where infections are probably most common, making it difficult to reach conclusions on how populations differ in terms of risk of infectious stroke. The treatment of infections and stroke, when concomitant, is based on almost no evidence and requires dedicated efforts to understand variations that might exist. We highlight the present knowledge and emphasise the need for stronger evidence to assist in the diagnosis, treatment, and secondary prevention of stroke in patients in whom an infectious cause for stroke is probable.

Pharmacologic inhibition of CXCL10 in combination with anti-malarial therapy eliminates mortality associated with murine model of cerebral malaria

Despite appropriate anti-malarial treatment, cerebral malaria (CM)-associated mortalities remain as high as 30%. Thus, adjunctive therapies are urgently needed to prevent or reduce such mortalities. Overproduction of CXCL10 in a subset of CM patients has been shown to be tightly associated with fatal human CM. Mice with deleted CXCL10 gene are partially protected against experimental cerebral malaria (ECM) mortality indicating the importance of CXCL10 in the pathogenesis of CM. However, the direct effect of increased CXCL10 production on brain cells is unknown. We assessed apoptotic effects of CXCL10 on human brain microvascular endothelial cells (HBVECs) and neuroglia cells in vitro. We tested the hypothesis that reducing overexpression of CXCL10 with a synthetic drug during CM pathogenesis will increase survival and reduce mortality. We utilized atorvastatin, a widely used synthetic blood cholesterol-lowering drug that specifically targets and reduces plasma CXCL10 levels in humans, to determine the effects of atorvastatin and artemether combination therapy on murine ECM outcome. We assessed effects of atorvastatin treatment on immune determinants of severity, survival, and parasitemia in ECM mice receiving a combination therapy from onset of ECM (day 6 through 9 post-infection) and compared results with controls. The results indicate that CXCL10 induces apoptosis in HBVECs and neuroglia cells in a dose-dependent manner suggesting that increased levels of CXCL10 in CM patients may play a role in vasculopathy, neuropathogenesis, and brain injury during CM pathogenesis. Treatment of ECM in mice with atorvastatin significantly reduced systemic and brain inflammation by reducing the levels of the anti-angiogenic and apoptotic factor (CXCL10) and increasing angiogenic factor (VEGF) production. Treatment with a combination of atorvastatin and artemether improved survival (100%) when compared with artemether monotherapy (70%), p<0.05. Thus, adjunctively reducing CXCL10 levels and inflammation by atorvastatin treatment during anti-malarial therapy may represent a novel approach to treating CM patients.

Therapeutic efficacy of artemether-lumefantrine combination in the treatment of uncomplicated malaria among children under five years of age in three ecological zones in Ghana

Background

In 2008, artemether - lumefantrine (AL) and dihydroartemisinin - piperaquine (DHAP) were added to artesunate - amodiaquine (AS-AQ) as first-line drugs for uncomplicated malaria in Ghana. The introduction of new drugs calls for continuous monitoring of these drugs to provide timely information on trends of their efficacy and safety to enhance timely evidence-based decision making by the National Malaria Control Programme. In this regard, the therapeutic efficacy of AL was monitored from September 2010 to April 2011 in four sentinel sites representing the three main ecological zones of the country.

Methods

The study was a one-arm prospective evaluation of clinical and parasitological responses to directly observed treatment for uncomplicated malaria among children aged 6 months to 59 months using the 2009 WHO protocol for surveillance of anti-malarial drug efficacy. Children recruited into the study received weight-based 20/120 mg AL at 0, 8, 24, 36, 48, and 60 hrs. Parasitaemia levels were assessed on days 2, 3, 7, 14, 21, 28, and at any time a study child was brought to the clinic with fever.

Results

A total of 175 children were enrolled into the study: 56 in the savanna zone, 78 in the forest zone and 41 in the coastal zone. Per-protocol analysis showed that the overall PCR-corrected cure rates on day 14 and day 28 were 96.5% (95% CI: 92.1, 98.6) and 95.4% (95% CI: 90.3, 98.0), respectively, with statistically significant differences between the ecological zones. The 90.4% day-28 cure rate observed in the savannah zone (95% CI: 78.2, 96.4) was significantly the lowest compared with 100% (95% CI: 93.2, 99.9) in the forest zone and 93.8% (95% CI: 77.8, 98.9) in the coastal zone (P = 0.017). Fever and parasite clearance were slower among children enrolled in the savannah zone. Gametocytaemia after day-3 post-treatment was rare in all the zones.

Conclusions

The study has shown that AL remains efficacious in Ghana with significant ecologic zonal differences. The savannah zone may be a potential zone for any emergence of resistant alleles as a result of the slower parasite clearance observed in the zone.

Artesunate versus quinine for treating severe malaria

BACKGROUND

Severe malaria results in over a million deaths every year, most of them in children aged under five years and living in sub-Saharan Africa. This review examines whether treatment with artesunate, instead of the standard treatment quinine, would result in fewer deaths and better treatment outcomes.

OBJECTIVES

To compare artesunate with quinine for treating severe malaria.

SEARCH METHODS

We searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (The Cochrane Library), MEDLINE, EMBASE, LILACS, ISI Web of Science, the metaRegister of Controlled trials (mRCT), conference proceedings, and reference lists of articles to November 2010.

SELECTION CRITERIA

Randomized controlled trials comparing intravenous, intramuscular, or rectal artesunate with intravenous or intramuscular quinine for treating adults and children with severe malaria who are unable to take medication by mouth.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the eligibility and risk of bias of trials, and extracted and analysed data. The primary outcome was all-cause death. Dichotomous outcomes were summarized using risk ratios (RR) and continuous outcomes by mean differences (MD). Where appropriate, we combined data in meta-analyses.

MAIN RESULTS

Eight trials enrolling 1664 adults and 5765 children are included in this review.Treatment with artesunate significantly reduced the risk of death both in adults (RR 0.61, 95% Confidence Interval (CI) 0.50 to 0.75; 1664 participants, five trials) and children (RR 0.76, 95% CI 0.65 to 0.90; 5765 participants, four trials)In children, treatment with artesunate increased the incidence of neurological sequelae at the time of hospital discharge. The majority of these sequelae were transient and no significant difference between treatments was seen at later follow up.

AUTHORS' CONCLUSIONS

The evidence clearly supports the superiority of parenteral artesunate over quinine for the treatment of severe malaria in both adults and children and in different regions of the world.

Protective efficacy of malaria case management and intermittent preventive treatment for preventing malaria mortality in children: a systematic review for the Lives Saved Tool

Background

The Lives Saved Tool (LiST) model was developed to estimate the impact of the scale-up of child survival interventions on child mortality. New advances in antimalarials have improved their efficacy of treating uncomplicated and severe malaria. Artemisinin-based combination therapies (ACTs) for uncomplicated Plasmodium falciparum malaria and parenteral or rectal artemisinin or quinine for severe malaria syndromes have been shown to be very effective for the treatment of malaria in children. These interventions are now being considered for inclusion in the LiST model. However, for obvious ethical reasons, their protective efficacy (PE) compared to placebo is unknown and their impact on reducing malaria-attributable mortality has not been quantified.

Methods

We performed systematic literature reviews of published studies in P. falciparum endemic settings to determine the protective efficacy (PE) of ACT treatment against malaria deaths among children with uncomplicated malaria, as well as the PE of effective case management including parenteral quinine against malaria deaths among all hospitalized children. As no randomized placebo-controlled trials of malaria treatment have been conducted, we used multiple data sources to ascertain estimates of PE, including a previously performed Delphi estimate for treatment of uncomplicated malaria.

Results

Based on multiple data sources, we estimate the PE of ACT treatment of uncomplicated P. falciparum malaria on reducing malaria mortality in children 1–23 months to be 99% (range: 94-100%), and in children 24-59 months to be 97% (range: 86-99%). We estimate the PE of treatment of severe P. falciparum malaria with effective case management including intravenous quinine on reducing malaria mortality in children 1-59 months to be 82% (range: 63-94%) compared to no treatment.

Conclusions

This systematic review quantifies the PE of ACT used for treating uncomplicated malaria and effective case management including parenteral quinine for treating severe P. falciparum malaria for preventing malaria mortality in children <5. These data will be used in the Lives Saved Tool (LiST) model for estimating the impact of scaling-up these interventions against malaria. However, in order to estimate the reduction in child mortality due to scale-up of these interventions, it is imperative to develop standardized indicators to measure population coverage of these interventions.

Artemether and artesunate show the highest efficacies in rescuing mice with late-stage cerebral malaria and rapidly decrease leukocyte accumulation in the brain

The murine model of cerebral malaria (ECM) caused by Plasmodium berghei ANKA (PbA) infection in susceptible mice has been extensively used for studies of pathogenesis and identification of potential targets for human CM therapeutics. However, the model has been seldom explored to evaluate adjunctive therapies for this malaria complication. A first step toward this goal is to define a treatment protocol with an effective antimalarial drug able to rescue mice presenting late-stage ECM. We evaluated the efficacy of artemisinin, artemether, artesunate, and quinine given intraperitoneally once a day, and combinations with mefloquine, in suppressing PbA infection in mice with moderate parasitemia. Artemether, artesunate, and quinine were then evaluated for efficacy in rescuing PbA-infected mice with ECM, strictly defined by using objective criteria based on the presentation of clinical signs of neurological involvement, degree of hypothermia, and performance in a set of six motor behavior tests. Artemether at 25 mg/kg presented the fastest parasite killing ability in 24 h and fully avoided recrudescence in a 5-day treatment protocol. Artemether and artesunate were equally effective in rescuing mice with late-stage ECM (46 and 43% survival, respectively), whereas quinine had a poor performance (12.5% survival). Artemether caused a marked decrease in brain leukocyte accumulation 24 h after the first dose. In conclusion, artemether and artesunate are effective in rescuing mice with late-stage ECM and decrease brain inflammation. In addition, the described protocols for more strict clinical evaluation and for rescue treatment provide a framework for studies of CM adjunctive therapies using this mouse model.

Artesunate versus quinine for treating severe malaria

BACKGROUND

Severe malaria results in over a million deaths every year, most of them in children aged under five years and living in sub-Saharan Africa. This review examines whether treatment with artesunate, instead of the standard treatment quinine, would result in fewer deaths and better treatment outcomes.

OBJECTIVES

To compare artesunate with quinine for treating severe malaria.

SEARCH STRATEGY

We searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (The Cochrane Library), MEDLINE, EMBASE, LILACS, ISI Web of Science, the metaRegister of Controlled trials (mRCT), conference proceedings, and reference lists of articles to November 2010.

SELECTION CRITERIA

Randomized controlled trials comparing intravenous, intramuscular, or rectal artesunate with intravenous or intramuscular quinine for treating adults and children with severe malaria who are unable to take medication by mouth.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the eligibility and risk of bias of trials, and extracted and analysed data. The primary outcome was all-cause death. Dichotomous outcomes were summarized using risk ratios (RR) and continuous outcomes by mean differences (MD). Where appropriate, we combined data in meta-analyses.

MAIN RESULTS

Eight trials enrolling 1664 adults and 5765 children are included in this review.Treatment with artesunate significantly reduced the risk of death both in adults (RR 0.61, 95% Confidence Interval (CI) 0.50 to 0.75; 1664 participants, five trials) and children (RR 0.76, 95% CI 0.65 to 0.90; 5765 participants, four trials)In children, treatment with artesunate increased the incidence of neurological sequelae at the time of hospital discharge. The majority of these sequelae were transient and no significant difference between treatments was seen at later follow up.

AUTHORS' CONCLUSIONS

The evidence clearly supports the superiority of parenteral artesunate over quinine for the treatment of severe malaria in both adults and children and in different regions of the world.

The model of Western integrative medicine: the role of Chinese medicine

The basic concept of integrative medicine (IM) is that by combining mainstream (biomedicine) with complementary and alternative medicine (CAM), synergistic therapeutic effects can be attained. When the methods of mind/body medicine (MBM) are added to this combination, as in Western countries, a new concept emerges that drastically changes the approach toward illness.It is interesting to note that the joining of traditional Chinese medicine and Western medicine in the early days of the Peoples' Republic of China preceded the Western model of IM by almost 50 years. Several elements that make up the key components of IM as practiced today in the West were already present in the Chinese version of IM, and Chinese medicine has played and continues to play an important role in advancing IM. However, one of the major differences between the Chinese and the Western models of IM today, besides MBM and some other treatment options, is that Western integrative medicine (WIM) strictly requires its CAM methods to be supported by scientific evidence.The therapeutic methods of IM and their applications are many and varied. However, they are most frequently employed to treat chronic medical conditions, e.g., bronchial asthma, rheumatic disease, chronic inflammatory bowel disorder and chronic pain. Other fields in which IM may be applied are internal medicine (inflammatory bowel diseases and cardiovascular diseases), musculoskeletal disorders, oncology (chemotherapy-induced side effects), obstetrics and gynecology (dysmenorrhea, endometriosis, infertility and menopausal complaints), pediatrics, geriatrics, neurology (migraine and chronic headache), and psychiatry (anxiety and depression).The concept of WIM is discussed here in detail by reviewing its scope and implications for the practice of medicine and focusing on the role of Chinese medicine in WIM.

Early variations in plasmodium falciparum dynamics in Nigerian children after treatment with two artemisinin-based combinations: implications on delayed parasite clearance

Background

Combination treatments, preferably containing an artemisinin derivative, are recommended to improve efficacy and prevent Plasmodium falciparum drug resistance. Artemether-lumefantrine (AL) and artesunate-amodiaquine (AA) are efficacious regimens that have been widely adopted in sub-Saharan Africa. However, most study designs ignore the effects of these regimens on peripheral parasitaemia in the first 24 hours of therapy. The study protocol was designed to evaluate more closely the early effects and the standard measures of efficacies of these two regimens.

Methods

In an open label, randomized controlled clinical trial, children aged 12 months to 132 months were randomized to receive AL (5-14 kg, one tablet; 15-24 kg, two tablets and 25-34 kg, three tablets twice daily) or artesunate (4 mg/kg daily) plus amodiaquine (10 mg/kg daily) for three days. Peripheral blood smears were made hourly in the first 4 hours, 8 h, 16 h, 24 h, and daily on days 2-7, and on days 7, 14, 21, 28, 35, and 42 for microscopic identification and quantification of Plasmodium falciparum.

Results

A total of 193 children were randomized to receive either AL (97) or AA (96). In children that received both medications, early response of peripheral parasitaemia showed that 42% of children who received AL and 36.7% of those who received AA had an immediate rise in peripheral parasitaemia (0-4 h after treatment) followed by a rapid fall. The rise in parasitaemia was significant and seems to suggest a mobilization of asexual parasites from the deep tissues to the periphery. Days 3, 7, 14, 28, and 42 cure rates in the per protocol (PP) population were > 90% in both groups of children. Both drug combinations were well tolerated with minimal side effects.

Conclusion

The study showed the high efficacy of AL and AA in Nigerian children. In addition the study demonstrated the mobilisation of asexual parasites from the deep to the periphery in the early hours of commencing ACT treatment in a subset of patients in both study groups. It is unclear whether the early parasite dynamics discovered in this study play any role in the development of drug resistance and thus it is important to further evaluate this discovery. It may be useful for studies investigating delay in parasite clearance of artemisinin derivatives as a way of monitoring the development of resistance to artemisinin to assess the early effects of the drugs on the parasites.

Comparative effectiveness of medical interventions in adults versus children

OBJECTIVE

To estimate the comparative effectiveness of medical interventions in adults versus children.

STUDY DESIGN

We identified from the Cochrane Database of Systematic Reviews (Issue 1, 2007) meta-analyses with data on at least 1 adult and 1 pediatric randomized trial with binary primary efficacy outcome. For each meta-analysis, we calculated the summary odds ratio of the adult trials and the pediatric trials, respectively; the relative odds ratio (ROR) of the adult versus pediatric odds ratios per meta-analysis; and the summary ROR across all meta-analyses. ROR <1 means that the experimental intervention is more unfavorable in children than adults.

RESULTS

Across 128 eligible meta-analyses (1051 adult and 343 pediatric trials), the summary ROR did not show a statistically significant difference between adults and children (0.96; 95% confidence intervals, 0.86 to 1.08). However, in all meta-analyses except for 1, the individual ROR's 95% confidence intervals could not exclude a relative difference in efficacy over 20%. In two-thirds, the relative difference in observed point estimates exceeded 50%. Nine statistically significant discrepancies were identified; 4 of them were also clinically important.

CONCLUSIONS

Treatment effects are on average similar in adults and children, but available evidence leaves large uncertainty about their relative efficacy. Clinically important discrepancies may occur.

Murine cerebral malaria is associated with a vasospasm-like microcirculatory dysfunction, and survival upon rescue treatment is markedly increased by nimodipine

Brain hemodynamics in cerebral malaria (CM) is poorly understood, with apparently conflicting data showing microcirculatory hypoperfusion and normal or even increased blood flow in large arteries. Using intravital microscopy to assess the pial microvasculature through a closed cranial window in the murine model of CM by Plasmodium berghei ANKA, we show that murine CM is associated with marked decreases (mean: 60%) of pial arteriolar blood flow attributable to vasoconstriction and decreased blood velocity. Leukocyte sequestration further decreased perfusion by narrowing luminal diameters in the affected vessels and blocking capillaries. Remarkably, vascular collapse at various degrees was observed in 44% of mice with CM, which also presented more severe vasoconstriction. Coadministration of artemether and nimodipine, a calcium channel blocker used to treat postsubarachnoid hemorrhage vasospasm, to mice presenting CM markedly increased survival compared with artemether plus vehicle only. Administration of nimodipine induced vasodilation and increased pial blood flow. We conclude that vasoconstriction and vascular collapse play a role in murine CM pathogenesis and nimodipine holds potential as adjunctive therapy for CM.

Discovery, mechanisms of action and combination therapy of artemisinin

Despite great international efforts, malaria still inflicts an enormous toll on human lives, especially in Africa. Throughout history, antimalarial medicines have been one of the most powerful tools in malaria control. However, the acquisition and spread of parasite strains that are resistant to multiple antimalarial drugs have become one of the greatest challenges to malaria treatment, and are associated with the increase in morbidity and mortality in many malaria-endemic countries. To deal with this grave situation, artemisinin-based combinatory therapies (ACTs) have been introduced and widely deployed in malarious regions. Artemisinin is a new class of antimalarial compounds discovered by Chinese scientists from the sweet wormwood Artemisia annua. The potential development of resistance to artemisinins by Plasmodium falciparum threatens the usable lifespan of ACTs, and therefore is a subject of close surveillance and extensive research. Studies at the Thai-Cambodian border, a historical epicenter of multidrug resistance, have detected reduced susceptibility to artemisinins as manifested by prolonged parasite-clearance times, raising considerable concerns on resistance development. Despite this significance, there is still controversy on the mode of action of artemisinins. Although a number of potential cellular targets of artemisinins have been proposed, they remain to be verified experimentally. Here, we review the history of artemisinin discovery, discuss the mode of action and potential drug targets, and present strategies to elucidate resistance mechanisms.

Chinese propriety medicines: an "alternative modernity?" The case of the anti-malarial substance artemisinin in East Africa

This article discusses various modes of "modernizing" traditional Chinese medical drugs (zhongyao [image: see text]) and transforming them into so-called Chinese propriety medicines (zhongchengyao [image: see text]) that are flooding the current neoliberal wellness markets. This article argues that the chemical procedures used in the manufacture of Chinese propriety medicines are highly culture-specific and deserve being considered as instantiations of an "alternative modernity" (e.g., Knauft 2002), rather than of "Westernization." These Western-Chinese combinations, produced in strife toward fulfilling Mao Zedong's Communist-revolutionary vision, have a potential to represent a critical alterity to Western health policies, challenging rhetoric against such combinations. However, as is also noted in this article based on ethnographic fieldwork in East Africa, their potential alterity has been corroded for at least two reasons. First, the medical rationale for dispensing these medications has been shaped by commercial demands in ways that have worked toward transforming the formerly scholarly Chinese medical tradition (as outlined by Bates 1995) into a consumer-near and popular "folk medicine" (as defined by Farquhar 1994:212). Second, the repertoire of Chinese propriety medicines is impoverished as its efficacious "alternatively modern" drugs are being redefined as "modern" biomedical drugs. The article concludes that the potentially critical alterity of any formerly scholarly traditional medicine is more likely to be lost in those fields of health care that are both highly commercialized and polarized by the biomedical imperative to distinguish between "traditional" and "modern" medicines. As example for demonstrating how contentious the issue is, qinghaosu [image: see text] (artemisinin) is put center stage. It is an anti-malarial substance which in the 1970s Chinese scientists extracted from the Chinese medical drug qinghao [image: see text] (Herba Artemisiae annuae). Some Chinese practitioners in East Africa argued that artemisinin belonged among the Chinese propriety medicines they sold. Although according to Western biomedical criteria and the Chinese scientists who were involved in its chemical identification, artemisinin is a "modern" Western drug, their polemics deserve to be more closely analyzed as what social scientists have recognized as an "alternative modernity."

Systematic reviews in malaria: global policies need global reviews

This article highlights systematic reviews of malaria research and what has been learned about applying methods of research synthesis in this particular infectious disease over the last 15 years. It illustrates how systematic reviews have been used to guide policy, shows what has been learned about synthesizing research in this area, and reflects on how best to maximize their uptake in policy and practice.

Characterization of cerebral malaria in the outbred Swiss Webster mouse infected by Plasmodium berghei ANKA

Plasmodium berghei ANKA (PbA) infection in susceptible inbred mouse strains is the most commonly used experimental model to study pathogenesis of cerebral malaria (CM). Indeed, many concepts on mechanisms related to this complication have arisen from works using this model. Although inbred strains present several advantages and are indicated for most studies, the use of outbred models can show unique usefulness in a number of approaches such as fine post-quantitative trait loci mapping and discovery of genes relevant to CM susceptibility or resistance, as well as pharmacological and vaccine studies. Here we describe the features of PbA infection and CM incidence, and characterize the associated multiorgan pathology in the outbred Swiss Webster mouse. This model showed a sizeable (62.7%) and reproducible incidence of CM demonstrated by clinical signs and histopathological changes in brain (microhaemorrhages, oedema and vessel plugging by mononuclear cells). Major pathological changes were also observed in lungs, liver, thymus and spleen, analogous to those observed in inbred strains. Parasitaemia levels were associated with the risk of CM development, the risk being significantly higher in mice showing higher values of parasitaemia on days 6-7 of infection. This outbred CM model is then suitable for genetic, vaccine and drug studies targeting this malaria complication.

Artesunate versus quinine for treating severe malaria

BACKGROUND

Severe malaria kills over a million people every year. We sought evidence of superiority of artesunate compared with the standard treatment quinine.

OBJECTIVES

To compare artesunate with quinine for treating severe malaria.

SEARCH STRATEGY

We searched the Cochrane Infectious Diseases Group Specialized Register (January 2007), CENTRAL (The Cochrane Library 2006, Issue 4), MEDLINE (1966 to January 2007), EMBASE (1974 to January 2007), LILACS (1982 to January 2007), ISI Web of Science (1945 to January 2007), the metaRegister of Controlled trials (mRCT), conference proceedings, and reference lists of articles. We contacted researchers and the World Health Organization.

SELECTION CRITERIA

Randomized controlled trials comparing intravenous, intramuscular, or rectal artesunate with intravenous or intramuscular quinine for treating adults and children with severe malaria who are unable to take medication by mouth.

DATA COLLECTION AND ANALYSIS

Two authors assessed the eligibility and methodological quality of trials, extracted and analysed data, and drafted the review. The third author contributed to the design and writing of the review. Death was the primary outcome. Dichotomous outcomes were summarized using relative risks and continuous outcomes by mean differences. Where appropriate, we combined data in meta-analyses. Heterogeneity was investigated for the primary outcome using subgroup analyses.

MAIN RESULTS

Six trials enrolling 1938 participants (1664 adults and 274 children) met our inclusion criteria. All six trials were conducted in Asia, and only one small trial enrolled only children. Five trials used intravenous artesunate and one trial intramuscular artesunate; all six used intravenous quinine. Treatment with artesunate significantly reduced the risk of death (RR 0.62, 95% CI 0.51 to 0.75; 1938 participants, 6 trials), reduced parasite clearance time (WMD 8.14 h, 95% CI 11.55 to 4.73; 292 participants, 3 trials), and hypoglycaemia detected by routine monitoring (RR 0.46, 95% CI 0.25 to 0.87; 185 participants, 2 trials). There was no evidence of a difference in neurological sequelae, coma recovery time, time to hospital discharge, fever clearance time, or adverse effects other than hypoglycaemia.

AUTHORS' CONCLUSIONS

Intravenous artesunate is the drug of choice for adults with severe malaria, particularly if acquired in Asia. This review did not identify sufficient data to make firm conclusions about the treatment of children or the effectiveness of intramuscular artesunate. There is an urgent need to compare the effects of artesunate with quinine in African children with severe malaria. The applicability of these results to Asian children and the ethics of further research are points of debate.

Hospitalization criteria in imported falciparum malaria

BACKGROUND

Controversy exists about the management of patients with imported Plasmodium falciparum malaria. We postulated that rapid parasite clearance supports ambulatory care, or, conversely, that factors associated with longer parasite clearance time (PCT) could be used as hospitalization criteria.

METHODS

Hospitalized patients with imported falciparum malaria recruited through one single travel clinic between 1993 and 2000. We used a linear regression to identify factors independently associated with PCT defined as the time in hours from antimalarial drug administration until the first negative malaria smear.

RESULTS

Among 400 patients hospitalized with falciparum malaria, mean (range) PCT was 58 (1-189) hours. In multivariate analysis, severe malaria, gastrointestinal signs, initial temperature greater than or equal to 40 degrees C, parasitemia greater than or equal to 1%, and platelet counts less than 50,000/microL were associated with longer PCT. Offering ambulatory care to patients aged 15 to 64 years with none of the factors associated with longer PCT in the study would have resulted in 147 (37%) patients receiving outpatient care.

CONCLUSION

Factors identified in this model may help physicians determine which P falciparum malaria patients can be treated on an ambulatory basis, and contribute to revisions of national guidelines for imported malaria management.

Efficacy and safety of dihydroartemisinin-piperaquine

Dihydroartemisinin-piperaquine, a fixed-dose combination antimalarial, is an inexpensive, safe and highly effective treatment for uncomplicated falciparum or vivax malaria. Efficacy assessed over 28-63 days has consistently exceeded 95% in the treatment of multidrug-resistant falciparum malaria. More than 2600 patients have been treated with this combination in prospective studies, mainly in Southeast Asia. Tolerability was uniformly good, and no serious adverse effects have been identified. The dosing regimen has been simplified from four doses to once daily over 3 days. More information on efficacy in Africa, and more pharmacokinetic and efficacy data in children are needed.

Malaria: an update on treatment of adults in non-endemic countries

Every year people die from malaria in Britain and other industrialised countries. Most of these deaths are avoidable: they occur because a patient or doctor has underestimated the severity of the disease or has not considered the diagnosis early enough. This article provides the essential facts on treating malaria in adults in a non-endemic setting and is based on the best available evidence

Malaria

Malaria is increasing worldwide due to the emergence and spread of drug resistant strains. This poses major health and economic problems for the population living in endemic areas and increases the risk of infections in travelers. The diagnosis of malaria relies on a biological proof of infection by microscopy or with a rapid test. The treatment must be initiated without delay preferably with an artemisinin containing regimen. Uncomplicated malaria can be treated with oral drugs while severe infections will be hospitalized and treated with injectables. Special attention will be given to the most susceptible groups: children and pregnant women.

Artesunate suppositories versus intramuscular artemether for treatment of severe malaria in children in Papua New Guinea

Drug treatment of severe malaria must be rapidly effective. Suppositories may be valuable for childhood malaria when circumstances prevent oral or parenteral therapy. We compared artesunate suppositories (n = 41; 8 to 16 mg/kg of body weight at 0 and 12 h and then daily) with intramuscular (i.m.) artemether (n = 38; 3.2 mg/kg at 0 h and then 1.6 mg/kg daily) in an open-label, randomized trial with children with severe Plasmodium falciparum malaria in Papua New Guinea (PNG). Parasite density and temperature were measured every 6 h for > or = 72 h. Primary endpoints included times to 50% and 90% parasite clearance (PCT50 and PCT90) and the time to per os status. In a subset of 29 patients, plasma levels of artemether, artesunate, and their common active metabolite dihydroartemisinin were measured during the first 12 h. One suppository-treated patient with multiple complications died within 2 h of admission, but the remaining 78 recovered uneventfully. Compared to the artemether-treated children, those receiving artesunate suppositories had a significantly earlier mean PCT50 (9.1 versus 13.8 h; P = 0.008) and PCT90 (15.6 versus 20.4 h; P = 0.011). Mean time to per os status was similar for each group. Plasma concentrations of primary drug plus active metabolite were significantly higher in the artesunate suppository group at 2 h postdose. The earlier initial fall in parasitemia with artesunate is clinically advantageous and mirrors higher initial plasma concentrations of active drug/metabolite. In severely ill children with malaria in PNG, artesunate suppositories were at least as effective as i.m. artemether and may, therefore, be useful in settings where parenteral therapy cannot be given.

Artesunate plus mefloquine versus mefloquine for treating uncomplicated malaria

BACKGROUND

Multiple-drug-resistant malaria is widespread, and in South-East Asia resistance is high against nearly all single therapy antimalarial drugs. Here, and in other areas with low malaria transmission, the combination of artesunate and mefloquine may provide an effective alternative.

OBJECTIVES

To compare artesunate plus mefloquine with mefloquine alone for treating uncomplicated Plasmodium falciparum malaria.

SEARCH STRATEGY

We searched the Cochrane Infectious Diseases Group Specialized Register (May 2005), CENTRAL (The Cochrane Library Issue 2, 2005), MEDLINE (1966 to May 2005), EMBASE (1988 to May 2005), LILACS (May 2005), BIOSIS (1985 to June 2005), conference proceedings, and reference lists. We also contacted researchers, organizations, and pharmaceutical companies.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials comparing artesunate plus mefloquine with mefloquine alone for treating uncomplicated malaria.

DATA COLLECTION AND ANALYSIS

Two authors independently applied the inclusion criteria, extracted data, and assessed methodological quality. The primary outcome was treatment failure by day 28, defined as evidence of parasitaemia with or without clinical failure between days zero (start of treatment) and 28. For dichotomous data we calculated relative risks (RR) and 95% confidence intervals (CI).

MAIN RESULTS

Eight trials involving 1996 participants met the inclusion criteria. All were conducted in areas with low malaria transmission, seven in South-East Asia and one in the Peruvian Amazon. The doses and dosing regimens of artesunate and mefloquine varied across trials. The trials using a total dose of 25 mg/kg mefloquine and 10 mg artesunate reported fewer treatment failures with the combination at all time points: day 28 (RR 0.17, 95% CI 0.06 to 0.47; 824 participants, 4 trials), day 42 (RR 0.23, 95% CI 0.14 to 0.39; 298 participants, 1 trial), and day 63 (RR 0.26, 95% CI 0.09 to 0.77; 501 participants, 2 trials). The results for parasitaemia showed a similar trend. Trials using a lower dose of artesunate tended to favour the artesunate plus mefloquine combination. Overall, adverse events were similar across treatment arms.

AUTHORS' CONCLUSIONS

Artesunate plus mefloquine performs better than mefloquine alone for treating uncomplicated falciparum malaria in areas with low malaria transmission. A total dose of 25 mg/kg mefloquine and at least 10 mg artesunate leads to higher cure rates. Better reporting of methods and standardisation of outcomes would help the interpretation of future trials.

Children in reviews: methodological issues in child-relevant evidence syntheses

BACKGROUND

The delivery of optimal medical care to children is dependent on the availability of child relevant research. Our objectives were to: i) systematically review and describe how children are handled in reviews of drug interventions published in the Cochrane Database of Systematic Reviews (CDSR); and ii) determine when effect sizes for the same drug interventions differ between children and adults.

METHODS

We systematically identified all of the reviews relevant to child health in the CDSR 2002, Issue 4. Reviews were included if they investigated the efficacy or effectiveness of a drug intervention for a condition that occurs in both children and adults. Information was extracted on review characteristics including study methods, results, and conclusions.

RESULTS

From 1496 systematic reviews, 408 (27%) were identified as relevant to both adult and child health; 52% (213) of these included data from children. No significant differences were found in effect sizes between adults and children for any of the drug interventions or conditions investigated. However, all of the comparisons lacked the power to detect a clinically significant difference and wide confidence intervals suggest important differences cannot be excluded. A large amount of data was unavailable due to inadequate reporting at the trial and systematic review level.

CONCLUSION

Overall, the findings of this study indicate there is a paucity of child-relevant and specific evidence generated from evidence syntheses of drug interventions. The results indicate a need for a higher standard of reporting for participant populations in studies of drug interventions.

Intramuscular arteether for treating severe malaria

BACKGROUND

Quinine and artemisinin drugs are used in severe malaria, but quinine resistance is increasing. Arteether is a recently developed artemisinin derivative that is oil soluble, has a long elimination half life, and is more stable than other derivatives.

OBJECTIVES

To compare intramuscular arteether with other antimalarial drugs to treat severe malaria.

SEARCH STRATEGY

We searched the Cochrane Infectious Diseases Group Specialized Register (August 2004), CENTRAL (The Cochrane Library Issue 3, 2004), MEDLINE (1966 to August 2004), EMBASE (1980 to August 2004), U.S. National Library of Medicine (NLM) Gateway (1953 to 1965), Web Science Citation (1981 to August 2004), LILACS (August 2004), Google search engine (August 2004), conference proceedings, and reference lists. We also contacted researchers, organizations, and pharmaceutical companies to help identify trials.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials of intramuscular arteether in adults and children with severe malaria.

DATA COLLECTION AND ANALYSIS

We independently assessed the methodological quality of the trials and extracted data, and analysed data using Review Manager 4.2.

MAIN RESULTS

Two small trials (n = 194) met the inclusion criteria. Both trials compared arteether with quinine in children with cerebral malaria and reported on similar outcomes. There was no statistically significant difference in the number of deaths (relative risk 0.75, 95% confidence interval 0.43 to 1.30; n = 194, 2 trials), neurological complications (relative risk 1.18, 95% confidence interval 0.31 to 4.46; n = 58, 1 trial), or other outcomes including time to regain consciousness, parasite clearance time, and fever clearance time. The meta-analyses lack statistical power to detect important differences.

REVIEWERS' CONCLUSIONS

More trials with a larger number of participants are needed before a firm conclusion about the efficacy and safety of arteether can be reached.

The potential of artemether for the control of schistosomiasis

Schistosomiasis continues to rank--following malaria--at the second position of the world's parasitic diseases in terms of the extent of endemic areas and the number of infected people. There is yet no vaccine available and the current mainstay of control is chemotherapy with praziquantel used as the drug of choice. In view of concern about the development of tolerance and/or resistance to praziquantel, there is a need for research and development of novel drugs for the prevention and cure of schistosomiasis. Interestingly, derivatives of artemisinin, which are already effectively used in the treatment of malaria, also exhibit antischistosomal properties. Significant advances have been made with artemether, the methyl ether derivative of artemisinin. We review the discovery of the antischistosomal activity of artemether by Chinese scientists two decades ago; the detailed laboratory studies of the susceptibility of, and effect on, the different developmental stages of Schistosoma japonicum, Schistosoma mansoni and Schistosoma haematobium to artemether; the possible mechanism of action and the potential long-term toxicity. Finally, we look at the effect of combined treatment with artemether and praziquantel; and clinical findings thus far obtained from randomised controlled trials with oral artemether for the prevention of patent infections and morbidity. The review intends to create a forum for strategic discussion of how these laboratory and clinical findings could be translated into public health actions. We conclude that artemether--as part of integrated current control measures and adapted to specific socio-ecological and epidemiological settings--has considerable potential to significantly reduce the current burden of schistosomiasis in many parts of the world.