Randomized Field Trial to Assess the Safety and Efficacy of Dihydroartemisinin-Piperaquine for Seasonal Malaria Chemoprevention in School-Aged Children in Bandiagara, Mali

BACKGROUND

Owing to the increased cases of malaria in older children, the World Health Organization has recently recommended extending seasonal malaria chemoprevention (SMC) to children >5 years of age and using other effective drugs for malaria. In this study, we report the safety and efficacy of dihydroartemisinin-piperaquine (DHA-PQ) for SMC in school-aged children in Mali.

METHOD

This randomized, controlled trial included 345 participants aged 6-15 years randomized to receive DHA-PQ, sulfadoxine-pyrimethamine plus amodiaquine (SP-AQ), or no chemoprevention (albendazole) at a 1:1:1 ratio. Four rounds of SMC were conducted from September to December 2021. The participants were assessed 7 days after each round for safety and efficacy of the interventions.

RESULTS

Abdominal pain (11.8% vs 29.2%), headache (11.2% vs 19.2%), and vomiting (5.7% vs 15.2%) were frequently reported in the DHA-PQ and SP-AQ arms. On Day 120 of follow up, the incidence of clinical malaria was 0.01 episodes/person-month in the DHA-PQ and SP-AQ arms and 0.17 episodes/person-month in the control arm (P < .0001). Gametocytes were detected in 37 participants in all arms.

CONCLUSIONS

Children in DHA-PQ arm reported less adverse events compared to the SP-AQ arm. Both drugs were effective against clinical malaria and infection.

Therapeutic efficacy and safety of artesunate + amodiaquine and artemether + lumefantrine in treating uncomplicated Plasmodium falciparum malaria in children on the rainy south-east coast of Madagascar

Malaria is a major public health problem in Madagascar, particularly in coastal areas. We conducted a randomized, controlled, parallel-group study of artemisinin-based combination therapy (ACT) in Mananjary and Farafangana, two localities on the rainy south-east coast of Madagascar, from March to September 2018. The efficacy and safety of artesunate + amodiaquine (ASAQ) and artemether + lumefantrine (AL) were assessed according to the WHO protocol with a 28-day follow-up. Children aged 6 months to 14 years with uncomplicated Plasmodium falciparum malaria were randomized to receive ASAQ or AL for three days (1:1). 347/352 (98.5%) randomized patients reached the study endpoint on day 28. Crude adequate clinical and parasitological response (ACPR) rates were 100% (95% CI: 98.8-100%) in the ASAQ group and 96% (95% CI: 93.1-98.9%) in the AL group (per protocol population). However, the PCR-corrected ACPR rate was 97.7% (95% CI: 95.4-100%) in the AL group. Two cases of recrudescence and three of re-infection were observed. Mild and moderate adverse events, including gastrointestinal and/or nervous disorders, were reported in 11.9% (42/352) of patients. We found that ASAQ and AL were safe and efficacious for treating uncomplicated P. falciparum malaria. They may be used for treatment at health facilities and at the community level, and for mass drug administration campaigns.

Effectiveness and safety of intermittent preventive treatment with dihydroartemisinin-piperaquine or artesunate-amodiaquine for reducing malaria and related morbidities in schoolchildren in Tanzania: a randomised controlled trial

BACKGROUND

In high transmission settings, most school-aged children harbour malaria parasites without showing symptoms, often leading to anaemia and possibly impaired psychomotor and cognitive abilities. We aimed to assess the effectiveness and safety of intermittent preventive treatment for malaria in school-aged children (IPTsc) living in highly endemic areas.

METHODS

We did an open-label randomised controlled trial in seven primary schools in northeastern Tanzania. Schoolchildren aged 5-15 years were individually randomly assigned (1:1:1) to receive dihydroartemisinin-piperaquine, artesunate-amodiaquine, or standard of care (control) using a balanced block design. Drugs were administered by schoolteachers, with supervision from study nurses, at months 0 (baseline), 4, and 8, and were given in line with manufacturer's recommendations with dose based on the child's bodyweight. The primary endpoints were change from baseline in mean haemoglobin concentration at months 12 and 20, and clinical incidence of malaria and prevalence of parasitaemia at months 12 and 20 in the intervention groups versus the control group. The outcome data were collected through longitudinal surveys conducted every 4 months. Data were analysed on the basis of intention to treat (including all randomised participants) and per protocol (comprising children who completed the full 3-day regimen of all three IPTsc treatment rounds as assigned). This study is registered with ClinicalTrials.gov (NCT03640403).

FINDINGS

Of the 1797 children scheduled for clinical screening, 1566 were enrolled and randomly allocated (526 to receive dihydroartemisinin-piperaquine, 527 to receive artesunate-amodiaquine, and 513 to receive standard of care). Due to COVID-19-related school closures, only two schools were visited at month 12 (135 children in the dihydroartemisinin-piperaquine group, 131 in the artesunate-amodiaquine group, and 118 in the control group). At month 12, compared with the control group, the change from baseline in mean haemoglobin concentration was increased by 0·5 g/dL (95% CI 0·2 to 0·8; p<0·0001) in the dihydroartemisinin-piperaquine group and 0·5 g/dL (0·2 to 0·7; p=0·0020) in the artesunate-amodiaquine group in the intention-to-treat analysis (with similar findings in the per protocol analysis). In the same period, in the intention-to-treat analysis, the prevalence of malaria parasitaemia increased from 28·5% (138 of 485 participants) to 33·6% (39 of 116) in the control group, but decreased from 28·0% (139 of 497) to 12·0% (15 of 125) in the dihydroartemisinin-piperaquine group (-21·6 percentage points [95% CI -31·9 to -11·3], p=0·0001 vs control at month 12) and from 24·7% (124 of 502) to 16·0% (20 of 125) in the artesunate-amodiaquine group (-17·6 percentage points [-28·4 to -6·9], p=0·0015). The decrease for artesunate-amodiaquine was larger in the per protocol analysis (-25·3 percentage points [-36·3 to -14·2], p<0·0001). The protective effect of IPTsc against malaria parasitaemia was 64% (95% CI 39 to 79; p<0·0001) for dihydroartemisinin-piperaquine and 52% (23 to 70; p=0·0015) for artesunate-amodiaquine in the intention-to-treat analysis, and was slightly higher on per protocol analysis. The protective effect against clinical malaria at month 12 was 20% (95% CI 9 to 29; p=0·0002) for dihydroartemisinin-piperaquine and 19% (8 to 28; p=0·0004) for artesunate-amodiaquine. No significant differences in any primary outcomes between the intervention and control groups were noted at month 20. Dihydroartemisinin-piperaquine and artesunate-amodiaquine were associated with a small number of mild adverse events, and there were no treatment-related serious adverse events or deaths.

INTERPRETATION

IPTsc with dihydroartemisinin-piperaquine or artesunate-amodiaquine is a safe and effective approach to reducing malaria parasitaemia, clinical malaria, and related morbidities, and is feasible to implement through programmes delivered by schoolteachers.

FUNDING

Flemish Interuniversity Council (VLIRUOS), EU EDCTP2 programme (MaReCa project), and Global Minds 2019.

TRANSLATION

For the Swahili translation of the abstract see Supplementary Materials section.

Cardiovascular concentration-effect relationships of amodiaquine and its metabolite desethylamodiaquine: Clinical and preclinical studies

AIMS

Amodiaquine is a 4-aminoquinoline used extensively for the treatment and prevention of malaria. Orally administered amodiaquine is largely converted to the active metabolite desethylamodiaquine. Amodiaquine can cause bradycardia, hypotension, and electrocardiograph QT interval prolongation, but the relationship of these changes to drug concentrations is not well characterized.

METHODS

We conducted a secondary analysis of a pharmacokinetic study of the cardiac safety of amodiaquine (10 mg base/kg/day over 3 days) in 54 Kenyan adults (≥18 years) with uncomplicated malaria. Nonlinear mixed effects modelling was used to assess amodiaquine and desethylamodiaquine concentration-effect relationships for vital sign (pulse rate, blood pressure) and electrocardiograph interval (QT, QRS, PR) outcomes. We also measured the spontaneous beating heart rate after cumulative dosing of amodiaquine and desethylamodiaquine in isolated mouse atrial preparations.

RESULTS

Amodiaquine and desethylamodiaquine caused concentration-dependent mean decreases in pulse rate (1.9 beats/min per 100 nmol/L; 95% confidence interval: 1.5-2.4), supine systolic blood pressure (1.7 mmHg per 100 nmol/L; 1.2-2.1), erect systolic blood pressure (1.5 mmHg per 100 nmol/L; 1.0-2.0) and erect diastolic blood pressure (1.4 mmHg per 100 nmol/L; 1.0-1.7). The mean QT interval prolongation was 1.4 ms per 100 nmol/L irrespective of correction factor after adjustment for residual heart rate dependency. There was no significant effect of drug concentration on postural change in blood pressure or PR and QRS intervals. In mouse atria, the spontaneous beating rate was significantly reduced by amodiaquine (n = 6) and desethylamodiaquine (n = 8) at 3 μmol/L (amodiaquine: 10 ± 2%; desethylamodiaquine: 12 ± 3%) and 10 μmol/L (amodiaquine: 50 ± 7%; desethylamodiaquine: 46 ± 6%) concentrations with no significant difference in potency between the 2 compounds.

CONCLUSION

Amodiaquine and desethylamodiaquine have concentration-dependent effects on heart rate, blood pressure, and ventricular repolarization.

The cardiovascular effects of amodiaquine and structurally related antimalarials: An individual patient data meta-analysis

BACKGROUND

Amodiaquine is a 4-aminoquinoline antimalarial similar to chloroquine that is used extensively for the treatment and prevention of malaria. Data on the cardiovascular effects of amodiaquine are scarce, although transient effects on cardiac electrophysiology (electrocardiographic QT interval prolongation and sinus bradycardia) have been observed. We conducted an individual patient data meta-analysis to characterise the cardiovascular effects of amodiaquine and thereby support development of risk minimisation measures to improve the safety of this important antimalarial.

METHODS AND FINDINGS

Studies of amodiaquine for the treatment or prevention of malaria were identified from a systematic review. Heart rates and QT intervals with study-specific heart rate correction (QTcS) were compared within studies and individual patient data pooled for multivariable linear mixed effects regression. The meta-analysis included 2,681 patients from 4 randomised controlled trials evaluating artemisinin-based combination therapies (ACTs) containing amodiaquine (n = 725), lumefantrine (n = 499), piperaquine (n = 716), and pyronaridine (n = 566), as well as monotherapy with chloroquine (n = 175) for uncomplicated malaria. Amodiaquine prolonged QTcS (mean = 16.9 ms, 95% CI: 15.0 to 18.8) less than chloroquine (21.9 ms, 18.3 to 25.6, p = 0.0069) and piperaquine (19.2 ms, 15.8 to 20.5, p = 0.0495), but more than lumefantrine (5.6 ms, 2.9 to 8.2, p < 0.001) and pyronaridine (-1.2 ms, -3.6 to +1.3, p < 0.001). In individuals aged ≥12 years, amodiaquine reduced heart rate (mean reduction = 15.2 beats per minute [bpm], 95% CI: 13.4 to 17.0) more than piperaquine (10.5 bpm, 7.7 to 13.3, p = 0.0013), lumefantrine (9.3 bpm, 6.4 to 12.2, p < 0.001), pyronaridine (6.6 bpm, 4.0 to 9.3, p < 0.001), and chloroquine (5.9 bpm, 3.2 to 8.5, p < 0.001) and was associated with a higher risk of potentially symptomatic sinus bradycardia (≤50 bpm) than lumefantrine (risk difference: 14.8%, 95% CI: 5.4 to 24.3, p = 0.0021) and chloroquine (risk difference: 8.0%, 95% CI: 4.0 to 12.0, p < 0.001). The effect of amodiaquine on the heart rate of children aged <12 years compared with other antimalarials was not clinically significant. Study limitations include the unavailability of individual patient-level adverse event data for most included participants, but no serious complications were documented.

CONCLUSIONS

While caution is advised in the use of amodiaquine in patients aged ≥12 years with concomitant use of heart rate-reducing medications, serious cardiac conduction disorders, or risk factors for torsade de pointes, there have been no serious cardiovascular events reported after amodiaquine in widespread use over 7 decades. Amodiaquine and structurally related antimalarials in the World Health Organization (WHO)-recommended dose regimens alone or in ACTs are safe for the treatment and prevention of malaria.

Effectiveness of seasonal malaria chemoprevention (SMC) treatments when SMC is implemented at scale: Case-control studies in 5 countries

BACKGROUND

Seasonal malaria chemoprevention (SMC) has shown high protective efficacy against clinical malaria and severe malaria in a series of clinical trials. We evaluated the effectiveness of SMC treatments against clinical malaria when delivered at scale through national malaria control programmes in 2015 and 2016.

METHODS AND FINDINGS

Case-control studies were carried out in Mali and The Gambia in 2015, and in Burkina Faso, Chad, Mali, Nigeria, and The Gambia in 2016. Children aged 3-59 months presenting at selected health facilities with microscopically confirmed clinical malaria were recruited as cases. Two controls per case were recruited concurrently (on or shortly after the day the case was detected) from the neighbourhood in which the case lived. The primary exposure was the time since the most recent course of SMC treatment, determined from SMC recipient cards, caregiver recall, and administrative records. Conditional logistic regression was used to estimate the odds ratio (OR) associated with receipt of SMC within the previous 28 days, and SMC 29 to 42 days ago, compared with no SMC in the past 42 days. These ORs, which are equivalent to incidence rate ratios, were used to calculate the percentage reduction in clinical malaria incidence in the corresponding time periods. Results from individual countries were pooled in a random-effects meta-analysis. In total, 2,126 cases and 4,252 controls were included in the analysis. Across the 7 studies, the mean age ranged from 1.7 to 2.4 years and from 2.1 to 2.8 years among controls and cases, respectively; 42.2%-50.9% and 38.9%-46.9% of controls and cases, respectively, were male. In all 7 individual case-control studies, a high degree of personal protection from SMC against clinical malaria was observed, ranging from 73% in Mali in 2016 to 98% in Mali in 2015. The overall OR for SMC within 28 days was 0.12 (95% CI: 0.06, 0.21; p < 0.001), indicating a protective effectiveness of 88% (95% CI: 79%, 94%). Effectiveness against clinical malaria for SMC 29-42 days ago was 61% (95% CI: 47%, 72%). Similar results were obtained when the analysis was restricted to cases with parasite density in excess of 5,000 parasites per microlitre: Protective effectiveness 90% (95% CI: 79%, 96%; P<0.001), and 59% (95% CI: 34%, 74%; P<0.001) for SMC 0-28 days and 29-42 days ago, respectively. Potential limitations include the possibility of residual confounding due to an association between exposure to malaria and access to SMC, or differences in access to SMC between patients attending a clinic and community controls; however, neighbourhood matching of cases and controls, and covariate adjustment, attempted to control for these aspects, and the observed decline in protection over time, consistent with expected trends, argues against a major bias from these sources.

CONCLUSIONS

SMC administered as part of routine national malaria control activities provided a very high level of personal protection against clinical malaria over 28 days post-treatment, similar to the efficacy observed in clinical trials. The case-control design used in this study can be used at intervals to ensure SMC treatments remain effective.

Effectiveness of seasonal malaria chemoprevention at scale in west and central Africa: an observational study

BACKGROUND

Seasonal malaria chemoprevention (SMC) aims to prevent malaria in children during the high malaria transmission season. The Achieving Catalytic Expansion of SMC in the Sahel (ACCESS-SMC) project sought to remove barriers to the scale-up of SMC in seven countries in 2015 and 2016. We evaluated the project, including coverage, effectiveness of the intervention, safety, feasibility, drug resistance, and cost-effectiveness.

METHODS

For this observational study, we collected data on the delivery, effectiveness, safety, influence on drug resistance, costs of delivery, impact on malaria incidence and mortality, and cost-effectiveness of SMC, during its administration for 4 months each year (2015 and 2016) to children younger than 5 years, in Burkina Faso, Chad, The Gambia, Guinea, Mali, Niger, and Nigeria. SMC was administered monthly by community health workers who visited door-to-door. Drug administration was monitored via tally sheets and via household cluster-sample coverage surveys. Pharmacovigilance was based on targeted spontaneous reporting and monitoring systems were strengthened. Molecular markers of resistance to sulfadoxine-pyrimethamine and amodiaquine in the general population before and 2 years after SMC introduction was assessed from community surveys. Effectiveness of monthly SMC treatments was measured in case-control studies that compared receipt of SMC between patients with confirmed malaria and neighbourhood-matched community controls eligible to receive SMC. Impact on incidence and mortality was assessed from confirmed outpatient cases, hospital admissions, and deaths associated with malaria, as reported in national health management information systems in Burkina Faso and The Gambia, and from data from selected outpatient facilities (all countries). Provider costs of SMC were estimated from financial costs, costs of health-care staff time, and volunteer opportunity costs, and cost-effectiveness ratios were calculated as the total cost of SMC in each country divided by the predicted number of cases averted.

FINDINGS

12 467 933 monthly SMC treatments were administered in 2015 to a target population of 3 650 455 children, and 25 117 480 were administered in 2016 to a target population of 7 551 491. In 2015, among eligible children, mean coverage per month was 76·4% (95% CI 74·0-78·8), and 54·5% children (95% CI 50·4-58·7) received all four treatments. Similar coverage was achieved in 2016 (74·8% [72·2-77·3] treated per month and 53·0% [48·5-57·4] treated four times). In 779 individual case safety reports over 2015-16, 36 serious adverse drug reactions were reported (one child with rash, two with fever, 31 with gastrointestinal disorders, one with extrapyramidal syndrome, and one with Quincke's oedema). No cases of severe skin reactions (Stevens-Johnson or Lyell syndrome) were reported. SMC treatment was associated with a protective effectiveness of 88·2% (95% CI 78·7-93·4) over 28 days in case-control studies (2185 cases of confirmed malaria and 4370 controls). In Burkina Faso and The Gambia, implementation of SMC was associated with reductions in the number of malaria deaths in hospital during the high transmission period, of 42·4% (95% CI 5·9 to 64·7) in Burkina Faso and 56·6% (28·9 to 73·5) in The Gambia. Over 2015-16, the estimated reduction in confirmed malaria cases at outpatient clinics during the high transmission period in the seven countries ranged from 25·5% (95% CI 6·1 to 40·9) in Nigeria to 55·2% (42·0 to 65·3) in The Gambia. Molecular markers of resistance occurred at low frequencies. In individuals aged 10-30 years without SMC, the combined mutations associated with resistance to amodiaquine (pfcrt CVIET haplotype and pfmdr1 mutations [86Tyr and 184Tyr]) had a prevalence of 0·7% (95% CI 0·4-1·2) in 2016 and 0·4% (0·1-0·8) in 2018 (prevalence ratio 0·5 [95% CI 0·2-1·2]), and the quintuple mutation associated with resistance to sulfadoxine-pyrimethamine (triple mutation in pfdhfr and pfdhps mutations [437Gly and 540Glu]) had a prevalence of 0·2% (0·1-0·5) in 2016 and 1·0% (0·6-1·6) in 2018 (prevalence ratio 4·8 [1·7-13·7]). The weighted average economic cost of administering four monthly SMC treatments was US$3·63 per child.

INTERPRETATION

SMC at scale was effective in preventing morbidity and mortality from malaria. Serious adverse reactions were rarely reported. Coverage varied, with some areas consistently achieving high levels via door-to-door campaigns. Markers of resistance to sulfadoxine-pyrimethamine and amodiaquine remained uncommon, but with some selection for resistance to sulfadoxine-pyrimethamine, and the situation needs to be carefully monitored. These findings should support efforts to ensure high levels of SMC coverage in west and central Africa.

FUNDING

Unitaid.

Safety and tolerability of artesunate-amodiaquine, artemether-lumefantrine and quinine plus clindamycin in the treatment of uncomplicated Plasmodium falciparum malaria in Kinshasa, the Democratic Republic of the Congo

INTRODUCTION

Artemisinin-based combination therapy is currently the best option for the treatment of uncomplicated malaria. Quinine is recommended as a rescue treatment. Safety information during repeated treatment with the same drug is scarce. We report safety data from the Quinact randomized clinical trial (RCT) that was designed to assess efficacy and safety of artesunate-amodiaquine (ASAQ), artemether-lumefantrine (AL) and quinine+clindamycin (QnC).

METHODOLOGY

Males and females aged 12 to 59 months with uncomplicated malaria were treated with ASAQ and followed up during 42 days (preRCT). Clinical failures were randomized to one of the 3 treatments and followed up for 28 days (RCT). Subsequent failures were repeatedly treated with ASAQ several times as needed (postRCT1, postRCT2 and so on) until a 28-days follow up period without parasitaemia.

RESULTS

Eight hundred and sixty-five, 242 and 64 patients were recruited respectively in preRCT, RCT and postRCTs. In preRCT, 433 (50.0%) patients experienced at least one drug-related adverse event (AE). The most reported AEs were anorexia (22.9%), asthenia (19.4%), and abnormal behavior (14.6%). Twenty-nine AEs (3.5%) were reported to be severe. In RCT, at least one drug-related AE was reported in 54.7%, 21.5% and 40.0% of patient randomized respectively to ASAQ, AL and QnC (p<0.001). During postRCT1 (n = 64), postRCT 2 (n = 17) and postRCT3 (n = 7), respectively 32.8%, 35.3% and 71.4% of patients experienced at least one drug-related AE. Three serious adverse events occurred but not judged related to study medication.

CONCLUSION

The proportion of AEs did not increase over the treatment courses with ASAQ. However, continuous monitoring is important.

Artemisia annua and Artemisia afra tea infusions vs. artesunate-amodiaquine (ASAQ) in treating Plasmodium falciparum malaria in a large scale, double blind, randomized clinical trial

BACKGROUND AND OBJECTIVE

Prior small-scale clinical trials showed that Artemisia annua and Artemisia afra infusions, decoctions, capsules, or tablets were low cost, easy to use, and efficient in curing malaria infections. In a larger-scale trial in Kalima district, Democratic Republic of Congo, we aimed to show A. annua and/or A. afra infusions were superior or at least equivalent to artesunate-amodiaquine (ASAQ) against malaria.

METHODS

A double blind, randomized clinical trial with 957 malaria-infected patients had two treatment arms: 472 patients for ASAQ and 471 for Artemisia (248 A. annua, 223 A. afra) remained at end of the trial. ASAQ-treated patients were treated per manufacturer posology, and Artemisia-treated patients received 1 l/d of dry leaf/twig infusions for 7 d; both arms had 28 d follow-up. Parasitemia and gametocytes were measured microscopically with results statistically compared among arms for age and gender.

RESULTS

Artemisinin content of A. afra was negligible, but therapeutic responses of patients were similar to A. annua-treated patients; trophozoites cleared after 24  h, but took up to 14 d to clear in ASAQ-treated patients. D28 cure rates defined as absence of parasitemia were for pediatrics 82, 91, and 50% for A. afra, A. annua and ASAQ; while for adults cure rates were 91, 100, and 30%, respectively. Fever clearance took 48  h for ASAQ, but 24  h for Artemisia. From D14-28 no Artemisia-treated patients had microscopically detectable gametocytes, while 10 ASAQ-treated patients remained gametocyte carriers at D28. More females than males were gametocyte carriers in the ASAQ arm but were unaffected in the Artemisia arms. Hemoglobin remained constant at 11 g/dl for A. afra after D1, while for A. annua and ASAQ it decreased to 9-9.5  g/dl. Only 5.0% of Artemisia-treated patients reported adverse effects, vs. 42.8% for ASAQ.

CONCLUSION

A. annua and A. afra infusions are polytherapies with better outcomes than ASAQ against malaria. In contrast to ASAQ, both Artemisias appeared to break the cycle of malaria by eliminating gametocytes. This study merits further investigation for possible inclusion of Artemisia tea infusions as an alternative for fighting and eradicating malaria.

Pyronaridine-artesunate for treating uncomplicated Plasmodium falciparum malaria

BACKGROUND

The World Health Organization (WHO) recommends artemisinin-based combination therapies (ACTs) to treat uncomplicated Plasmodium falciparum (P falciparum) malaria. Concerns about artemisinin resistance have led to global initiatives to develop new partner drugs to protect artemisinin derivatives in ACT. Pyronaridine-artesunate is a novel ACT.

OBJECTIVES

To evaluate the efficacy of pyronaridine-artesunate compared to alternative ACTs for treating people with uncomplicated P falciparum malaria, and to evaluate the safety of pyronaridine-artesunate and other pyronaridine treatments compared to alternative treatments.

SEARCH METHODS

We searched the Cochrane Infectious Diseases Group Specialized Register; Cochrane Central Register of Controlled Trials (CENTRAL), published in the Cochrane Library; MEDLINE; Embase; and LILACS. We also searched ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform Search Portal, and the International Standard Randomized Controlled Trial Number (ISRCTN) registry for ongoing or recently completed trials. The date of the last search was 8 May 2018.

SELECTION CRITERIA

Efficacy analysis: randomized controlled trials (RCTs) of pyronaridine-artesunate for treating uncomplicated P falciparum malaria.Safety analysis: RCTs of pyronaridine-artesunate or pyronaridine for treating P falciparum or P vivax malaria.

DATA COLLECTION AND ANALYSIS

For this update, two review authors independently re-extracted all data and assessed certainty of evidence. We meta-analysed data to calculate risk ratios (RRs) for treatment failures between comparisons, and for safety outcomes between and across comparisons.

MAIN RESULTS

We included 10 relevant studies. Seven studies were co-funded by Shin Poong Pharmaceuticals which manufactures the drug. Three studies were funded by government agencies.For efficacy analysis we identified five RCTs with 5711 participants. This included 4465 participants from 13 sites in Africa, and 1246 participants from five sites in Asia. It included 541 children aged less than five years.For polymerase chain reaction (PCR)-adjusted failures at day 28, pyronaridine-artesunate may have fewer failures compared to artemether-lumefantrine (RR 0.59, 95% confidence interval (CI) 0.26 to 1.31; 4 RCTs, 3068 participants, low-certainty evidence), artesunate-amodiaquine (RR 0.55, 95% CI 0.11 to 2.77; 1 RCT, 1245 participants, low-certainty evidence), and mefloquine plus artesunate (RR 0.37, 95% CI 0.13 to 1.05; 1 RCT, 1117 participants, low-certainty evidence).For unadjusted failures at day 28, pyronaridine-artesunate may have fewer failures compared to artemether-lumefantrine (RR 0.27, 95% CI 0.13 to 0.58; 4 RCTs, 3149 participants, low-certainty evidence), and probably has fewer failures compared to artesunate-amodiaquine (RR 0.49, 95% CI 0.30 to 0.81; 1 RCT, 1257 participants, moderate-certainty evidence) and mefloquine plus artesunate (RR 0.36, 95% CI 0.17 to 0.78; 1 RCT, 1120 participants, moderate-certainty evidence).For PCR-adjusted failures at day 42, pyronaridine-artesunate may make little or no difference compared to artemether-lumefantrine (RR 0.86, 95% CI 0.49 to 1.51; 4 RCTs, 2575 participants, low-certainty evidence) and artesunate-amodiaquine (RR 0.98, 95% CI 0.20 to 4.83; 1 RCT, 1091 participants, low-certainty evidence), but may have higher failures than mefloquine plus artesunate (RR 1.80, 95% CI 0.90 to 3.57; 1 RCT, 1037 participants, low-certainty evidence). Overall, pyronaridine-artesunate had a PCR-adjusted treatment failure rate of less than 5%.For unadjusted failures at day 42, pyronaridine-artesunate may have fewer failures compared to artemether-lumefantrine (RR 0.61, 95% CI 0.46 to 0.82; 4 RCTs, 3080 participants, low-certainty evidence), may make little or no difference compared to mefloquine plus artesunate (RR 0.84, 95% CI 0.54 to 1.31; 1 RCT, 1059 participants, low-certainty evidence), and probably makes little or no difference compared to artesunate-amodiaquine (RR 0.98, 95% CI 0.78 to 1.23; 1 RCT, 1235 participants, moderate-certainty evidence).For the safety analysis of severe adverse events and liver function, we identified eight RCTs with 6614 participants comparing pyronaridine-artesunate to other antimalarials, four of which were not in the previous version of this review. A further two RCTs, comparing pyronaridine alone to other treatments, contributed to the synthesis of all adverse events.Raised alanine aminotransferase (ALT) greater than five times the upper limit of normal (> 5 x ULN) is more frequent with pyronaridine-artesunate compared to other antimalarials (RR 3.34, 95% CI 1.63 to 6.84; 8 RCTS, 6581 participants, high-certainty evidence). There is probably little or no difference for raised bilirubin > 2.5 x ULN between pyronaridine-artesunate and other antimalarials (RR 1.03, 95% CI 0.49 to 2.18; 7 RCTs, 6384 participants, moderate-certainty evidence). There was one reported case in which raised ALT occurred with raised bilirubin, meeting criteria for moderate drug-induced liver injury. No study reported severe drug-induced liver injury. Electrocardiograph (ECG) abnormalities were less common with pyronaridine-artesunate compared to other antimalarials. We identified no other safety concerns.

AUTHORS' CONCLUSIONS

Pyronaridine-artesunate was efficacious against uncomplicated P falciparum malaria, achieved a PCR-adjusted treatment failure rate of less than 5% at days 28 and 42, and may be at least as good as, or better than other marketed ACTs.Pyronaridine-artesunate increases the risk of episodes of raised ALT > 5 x ULN. This meets criteria for mild drug-induced liver injury. On one instance this was linked to raised bilirubin, indicating moderate drug-induced liver injury. No episodes of severe drug-induced liver injury were reported. The findings of this review cannot fully inform a risk-benefit assessment for an unselected population. Readers should remain aware of this uncertainty when considering use of pyronaridine-artesunate in patients with known or suspected pre-existing liver dysfunction, and when co-administering with other medications which may cause liver dysfunction.

Safety of Artemisinin-Based Combination Therapies in Nigeria: A Cohort Event Monitoring Study

BACKGROUND

A pilot programme of Cohort Event Monitoring (CEM) was conducted across the six geopolitical zones of Nigeria on patients treated for uncomplicated malaria with artemisinin-based combination therapy (ACT). The emergence and spread of malaria parasites resistant to commonly available antimalarial drugs necessitated a shift in policy for malaria treatment by the Federal Government from the use of chloroquine and sulphadoxine-pyrimethamine (SP) as first-line treatments to ACTs. Initial reports following deployment of ACTs in clinical settings raised safety concerns regarding their use. Although artemisinin and its derivatives are generally thought to be safe, there are currently few or no data on their safety among populations in Nigeria.

OBJECTIVES

The main objectives of the CEM programme were to proactively determine the adverse event (AE) profile of artesunate/amodiaquine (AA) and artemether/lumefantrine (AL) in real-life settings and to find out the factors predisposing to AEs.

METHODS

The CEM study was observational, longitudinal, prospective, and inceptional. Patients were observed in real-life situations. It was conducted in six public health facilities in Nigeria on patients with a clinical diagnosis of uncomplicated malaria treated with ACTs. Patients were prescribed one of the ACTs on an alternate basis as they enrolled into the programme. Follow-up reviews were undertaken on days 3 and 7 following commencement of ACT treatment. At follow-up, patients were evaluated for any clinical event that they might have experienced following the use of the ACTs. We report the result of this initial pilot in which 3,010 patients treated for uncomplicated malaria with AA or AL were enrolled.

RESULTS

The seven most common AEs seen were general body weakness 25.0/36.6% (AL/AA); dizziness 11.9/17.2% (AL/AA); vomiting 8.0/10.2% (AL/AA); abdominal pain 8.5/7.2% (AL/AA); insomnia 6.3/5.9% (AL/AA); body pains 3.4/5.2 (AL/AA) %; anorexia 8.5/4.6% (AL/AA). Most adverse events occurred from day 1 and peaked by day 2 and 3 of medication with the mean duration of events being 3 days. By the end of the follow-up visit on day 7, the AEs had resolved in the majority of patients. Adverse events were more common in the AA group than AL revealing a better safety profile for AL (p < 0.001). Both ACTs demonstrated good ability to resolve the clinical symptoms of uncomplicated malaria.

CONCLUSION

In conclusion, this pilot CEM programme suggests that adverse events with ACTs were common. However, serious life-threatening events were not common. It appears that ACTs have a tolerable safety profile among Nigerians.

Safety of Seasonal Malaria Chemoprevention (SMC) with Sulfadoxine-Pyrimethamine plus Amodiaquine when Delivered to Children under 10 Years of Age by District Health Services in Senegal: Results from a Stepped-Wedge Cluster Randomized Trial

Background

It is recommended that children aged 3 months to five years of age living in areas of seasonal transmission in the sub-Sahel should receive Seasonal Malaria Chemoprevention (SMC) with sulfadoxine-pyrimethamine plus amodiaquine (SPAQ) during the malaria transmission season. The purpose of this study was to evaluate the safety of SMC with SPAQ in children when delivered by community health workers in three districts in Senegal where SMC was introduced over three years, in children from 3 months of age to five years of age in the first year, then in children up to 10 years of age.

Methods

A surveillance system was established to record all deaths and all malaria cases diagnosed at health facilities and a pharmacovigilance system was established to detect adverse drug reactions. Health posts were randomized to introduce SMC in a stepped wedge design. SMC with SPAQ was administered once per month from September to November, by nine health-posts in 2008, by 27 in 2009 and by 45 in 2010.

Results

After three years, 780,000 documented courses of SMC had been administered. High coverage was achieved. No serious adverse events attributable to the intervention were detected, despite a high level of surveillance.

Conclusions

SMC is being implemented in countries of the sub-Sahel for children under 5 years of age, but in some areas the age distribution of cases of malaria may justify extending this age limit, as has been done in Senegal. Our results show that SMC is well tolerated in children under five and in older children. However, pharmacovigilance should be maintained where SMC is implemented and provision for strengthening national pharmacovigilance systems should be included in plans for SMC implementation.

Trial Registration

ClinicalTrials.gov NCT 00712374

Efficacy of artesunate-amodiaquine for the treatment of acute uncomplicated falciparum malaria in southern Mauritania

BACKGROUND

A regular evaluation of therapeutic efficacy in sentinel sites and a system of surveillance are required to establish treatment guidelines and adapt national anti-malarial drug policy to the rapidly changing epidemiology of drug-resistant malaria. The current anti-malarial treatment guideline in Mauritania, officially recommended since 2006, is based on artemisinin-based combination therapy. The aim of the present study was to evaluate clinical efficacy and tolerance of artesunate-amodiaquine, the first-line treatment for acute uncomplicated malaria, in Mauritanian paediatric and adult patients to validate its continued use in the country.

METHODS

Plasmodium falciparum-infected symptomatic patients aged > six months were enrolled in Kobeni and Timbedra in southern Mauritania in September to October 2013. Co-formulated artesunate-amodiaquine was administered at the recommended dose over three days. Patients were followed until day 28. Parasitological and clinical response was classified according to the standard 2009 World Health Organization protocol.

RESULTS

A total of 130 patients (65 in Kobeni and 65 in Timbedra) were enrolled in the study. Seventeen patients (13.1%) were either excluded (before PCR correction) or lost to follow-up. Based on the per protocol analysis, artesunate-amodiaquine efficacy (i.e., the proportion of adequate clinical and parasitological response) was 96.6% in Kobeni and 98.2% in Timbedra before PCR correction. Late clinical failure was observed in two patients in Kobeni and one patient in Timbedra. After PCR correction, the efficacy rate in the two study sites was 98.2%. On day 3, all patients were afebrile and had negative smears. Treatment was well tolerated.

CONCLUSIONS

Artesunate-amodiaquine is well tolerated and highly efficacious for the treatment of uncomplicated P. falciparum malaria. In the majority of patients, fever and parasitaemia were rapidly cleared before day 3. The results support the national anti-malarial drug guideline for a continued use of artesunate-amodiaquine as a first-line drug for uncomplicated malaria in southern Mauritania.

Efficacy and safety of fixed-dose artesunate-amodiaquine vs. artemether-lumefantrine for repeated treatment of uncomplicated malaria in Ugandan children

The safety and efficacy of the two most widely used fixed-dose artemisinin-based combination therapies (ACT), artesunate-amodiaquine (ASAQ) and artemether-lumefantrine (AL) are well established for single episodes of uncomplicated Plasmodium falciparum malaria, but the effects of repeated, long-term use are not well documented. We conducted a 2-year randomized, open-label, longitudinal, phase IV clinical trial comparing the efficacy and safety of fixed-dose ASAQ and AL for repeated treatment of uncomplicated malaria in children under 5 years at Nagongera Health Centre, Uganda. Participants were randomized to ASAQ or AL and all subsequent malaria episodes were treated with the same regimen. 413 children were enrolled and experienced a total of 6027 malaria episodes (mean 15; range, 1–26). For the first malaria episode, the PCR-corrected-cure rate for ASAQ (97.5%) was non-inferior to that for AL (97.0%; 95% CI [−0.028; 0.037]). PCR-corrected cure rates for subsequent malaria episodes that had over 100 cases (episodes 2–18), ranged from 88.1% to 98.9% per episode, with no clear difference between the treatment arms. Parasites were completely cleared by day 3 for all malaria episodes and gametocyte carriage was less than 1% by day 21. Fever clearance was faster in the ASAQ group for the first episode. Treatment compliance for subsequent episodes (only first dose administration observed) was close to 100%. Adverse events though common were similar between treatment arms and mostly related to the disease. Serious adverse events were uncommon, comparable between treatment arms and resolved spontaneously. Anemia and neutropenia occurred in <0.5% of cases per episode, abnormal liver function tests occurred in 0.3% to 1.4% of cases. Both regimens were safe and effective for repeated treatment of malaria.

Trial Registration

Current Controlled Trials NCT00699920

Randomized comparison of the efficacies and tolerabilities of three artemisinin-based combination treatments for children with acute Plasmodium falciparum malaria in the Democratic Republic of the Congo

An open-label, randomized controlled trial was carried out in 2011-2012 in the Democratic Republic of the Congo to test the efficacy, safety, and tolerability of the artemisinin-based combination treatments dihydroartemisinin-piperaquine, amodiaquine-artesunate, and artemether-lumefantrine. Six hundred eighty-four children aged 3 to 59 months with uncomplicated Plasmodium falciparum malaria were randomly allocated to each study arm. Children were hospitalized for 3 days, given supervised treatment, and followed up weekly for 42 days. All regimens were well tolerated and rapidly effective. The median parasitemia clearance half-life was 2.2 h, and half-lives were similar between arms (P=0.19). The PCR-uncorrected cure rates by day 42 were 73.0% for amodiaquine-artesunate, 70.2% for artemether-lumefantrine, and 86.3% for dihydroartemisinin-piperaquine (P=0.001). Early treatment failure occurred in three patients (0.5%), one in each arm. The PCR-corrected cure rates were 93.4% for amodiaquine-artesunate, 92.7% for artemether-lumefantrine, and 94.3% for dihydroartemisinin-piperaquine (P=0.78). The last provided a longer posttreatment prophylactic effect than did the other two treatments. The day 7 plasma concentration of piperaquine was below 30 ng/ml in 47% of the children treated with dihydroartemisinin-piperaquine, and the day 7 lumefantrine concentration was below 280 ng/ml in 37.0% of children who received artemether-lumefantrine. Thus, although cure rates were all satisfactory, they could be improved by increasing the dose. (This study has been registered with the International Standard Randomized Controlled Trial Number Register [www.isrctn.org] under registration no. ISRCTN20984426.).

Efficacy and safety of artemether + lumefantrine, artesunate + sulphamethoxypyrazine-pyrimethamine and artesunate + amodiaquine and sulphadoxine-pyrimethamine + amodiaquine in the treatment of uncomplicated falciparum malaria in Bangui, Central African Republic: a randomized trial

BACKGROUND

The efficacy of artemisinin-based combination therapy (ACT) has been established. The objective of the present study was to compare the efficacy and safety in the Central African Republic (CAR) of three commercially available artemisinin-based combinations, artemether + lumefantrine (AL), artesunate + sulphamethoxypyrazine-pyrimethamine (AS-SMP) and artesunate + amodiaquine (AS-AQ), with those of sulphadoxine-pyrimethamine + amodiaquine (SP-AQ), which was the first-line reference treatment in the country from 2004, until it was replaced by ACT in 2006 in accordance with changes in international recommendations based on resistance identified in other regions.

METHODS

Children aged six to 59 months with uncomplicated Plasmodium falciparum malaria were recruited in Bangui, the capital of the CAR. The 251 patients selected were randomly assigned to receive AL (n = 60), AS-SMP (n = 58), AS-AQ (n = 68) or SP-AQ (n = 65) and were followed up for 28 days. Clinical outcome was classified according to the standard 2003 World Health Organization protocol.

RESULTS

At day 28, the cure rates in a per-protocol analysis were 92% (48/52) with AL, 93% (50/54) with AS-SMP, 93% (55/59) with AS-AQ and 100% (57/57) with SP-AQ, with no statistically significant difference between the four treatments. Defervescence was significantly faster with AS-AQ than with AL (p <0.035). Fatigue was reported significantly more frequently by patients receiving AQ than by those treated with AS-SMP or AL (p = 0.006). All the other adverse events reported were mild, and no significant difference was noted by treatment.

CONCLUSION

The three artemisinin-bsed combinations show similar, satisfactory results, comparable to that with SP-AQ. This evaluation is the first conducted in CAR since the official introduction of ACT. It should guide the National Malaria Control Programme in choosing the appropriate ACT for treatment of uncomplicated P. falciparum malaria in the future.

A randomized comparison of dihydroartemisinin-piperaquine and artesunate-amodiaquine combined with primaquine for radical treatment of vivax malaria in Sumatera, Indonesia

BACKGROUND

A high prevalence of chloroquine-resistant Plasmodium vivax in Indonesia has shifted first-line treatment to artemisinin-based combination therapies, combined with primaquine (PQ) for radical cure. Which combination is most effective and safe remains to be established.

METHODS

We conducted a prospective open-label randomized comparison of 14 days of PQ (0.25 mg base/kg) plus either artesunate-amodiaquine (AAQ + PQ) or dihydroartemisinin-piperaquine (DHP + PQ) for the treatment of uncomplicated monoinfection P. vivax malaria in North Sumatera, Indonesia. Patients were randomized and treatments were given without prior testing for G6PD status. The primary outcome was parasitological failure at day 42. Patients were followed up to 1 year.

RESULTS

Between December 2010 and April 2012, 331 patients were included. After treatment with AAQ + PQ, recurrent infection occurred in 0 of 167 patients within 42 days and in 15 of 130 (11.5%; 95% confidence interval [CI], 6.6%-18.3%) within a year. With DHP + PQ, this was 1 of 164 (0.6%; 95% CI, 0.01%-3.4%) and 13 of 143 (9.1%; 95% CI, 4.9%-15.0%), respectively (P > .2). Intravascular hemolysis occurred in 5 patients, of which 3 males were hemizygous for the G6PD-Mahidol mutation. Minor adverse events were more frequent with AAQ + PQ.

CONCLUSIONS

In North Sumatera, Indonesia, AAQ and DHP, both combined with PQ, were effective for blood-stage parasite clearance of uncomplicated P. vivax malaria. Both treatments were safe, but DHP + PQ was better tolerated.

CLINICAL TRIALS REGISTRATION

NCT01288820.

Tolerability and safety of artesunate-amodiaquine and artemether-lumefantrine fixed dose combinations for the treatment of uncomplicated Plasmodium falciparum malaria: two open-label, randomized trials in Nimba County, Liberia

BACKGROUND

Safety surveillance of widely used artemisinin-based combination therapy (ACT) is essential, but tolerability data in the over five years age group are largely anecdotal.

METHODS

Two open-label, randomized trials were conducted in Nimba County, Liberia: i) the main tolerability trial with 1,000 Plasmodium falciparum malaria patients aged over five years (Study-T), and, ii) an efficacy trial with a secondary objective of collecting tolerability data among 300 children age six to 59 months (Study-E). In both studies patients were randomized to fixed-dose artesunate-amodiaquine (ASAQ Winthrop®) or artemether-lumefantrine (AL, Coartem®), respectively. Clinical- and laboratory-adverse events (AEs) were recorded until day 28.

RESULTS

Study-T: most patients experienced at least one AE. Severe AEs were few, primarily asymptomatic blood system disorders or increased liver enzyme values. No treatment or study discontinuation occurred. Mild or moderate fatigue (39.8% vs 16.3%, p < 0.001), vomiting (7.1% vs 1.6%, p < 0.001), nausea (3.2% vs 1.0%, p = 0.01), and anaemia (14.9% vs 9.8%, p = 0.01) were more frequently recorded in the ASAQ versus AL arm. Study-E: mild or moderate AEs were common, including anaemia, fatigue, vomiting or diarrhoea. The few severe events were asymptomatic blood system disorders and four clinical events (pneumonia, malaria, vomiting and stomatitis).

CONCLUSION

Both ASAQ and AL were well tolerated in patients of all age groups. No unexpected AEs occurred. Certain mild or moderate AEs were more frequent in the ASAQ arm. Standardised safety surveillance should continue for all forms of ACT.

TRIAL REGISTRATION

The protocols were registered with Current Controlled Trials, under the identifier numbers ISRCTN40020296, ISRCTN51688713, (http://www.controlled-trials.com).

Artesunate- and amodiaquine-associated extrapyramidal reactions: a series of 49 cases in VigiBase™

BACKGROUND

Acute extrapyramidal reactions have been attributed to amodiaquine. They may be anticipated with the widely-used combination antimalarial artesunate with amodiaquine, but the association is very poorly documented.

OBJECTIVE

The aim of the study was to identify individual case safety reports in the Uppsala Monitoring Centre's Vigibase™ database associating the use of the combination of artesunate and amodiaquine with extrapyramidal adverse reactions and to characterize the clinical features in those reports.

METHODS

Reports of adverse reactions to the combination use of artesunate or dihydroartemisinin and amodiaquine entered into Vigibase™ up to 15 February 2011 were identified. Reports with a causality grading of 'Unlikely' and probable duplicates of reports were excluded. Reports that included at least one MedDRA® Preferred Term strongly suggestive of an extrapyramidal reaction were subject to further detailed analysis.

RESULTS

Forty-three reports in adults and six reports in children were identified as associating the use of artesunate with amodiaquine, either as separate co-packaged or fixed-combination products, with extrapyramidal reactions. More than half (57%) of the adults had an onset of the reaction within 48 hours of starting treatment. Almost equal numbers of male and female adult patients were reported - 67% were aged between 14 and 30 years. The most commonly implicated daily dose was amodiaquine base 600 mg and artesunate 200 mg, but lower doses were implicated in some adult patients. Identification of very long delays in some reports reaching Vigibase™ was an unexpected observation.

CONCLUSIONS

This case series supports an association of the use of artesunate and amodiaquine as combination antimalarial therapy with acute extrapyramidal reactions. The reactions occurred with recommended, and in some instances reduced, daily doses. Extrapyramidal reactions are unpleasant and frightening and the association warrants being more clearly recorded in official treatment guidelines and Summary of Product Characteristics documents.

Repeated artemisinin-based combination therapies in a malaria hyperendemic area of Mali: efficacy, safety, and public health impact

Artemisinin-based combination therapies (ACTs) are the first-line treatment of uncomplicated malaria. The public health benefit and safety of repeated administration of a given ACT are poorly studied. We conducted a randomized trial comparing artemether-lumefantrine, artesunate plus amodiaquine (AS+AQ) and artesunate plus sulfadoxine-pyrimethamine (AS+SP) in patients 6 months of age and older with uncomplicated malaria in Mali from July 2005 to July 2007. The patient received the same initial treatment of each subsequent uncomplicated malaria episode except for treatment failures where quinine was used. Overall, 780 patients were included. Patients in the AS+AQ and AS+SP arms had significantly less risk of having malaria episodes; risk ratio (RR) = 0.84 (P = 0.002) and RR = 0.80 (P = 0.001), respectively. The treatment efficacy was similar and above 95% in all arms. Although all drugs were highly efficacious and well tolerated, AS+AQ and AS+SP were associated with less episodes of malaria.

Reversible binocular visual loss in temporal association with artesunate-amodiaquine treatment in a child on mefloquine chemoprophylaxis

A case of an acute reversible visual loss in a 10-year-old child who was on mefloquine prophylaxis, and was treated with artesunate-amodiaquine for an acute febrile illness diagnosed clinically as uncomplicated malaria, is reported. On admission the patient could not perceive light and had bilateral papilloedema. She was treated with dexamethasone and recovered her sight gradually over a 21-day period. There has been no previous report to our knowledge, of an association between acute visual loss and mefloquine, amodiaquine, or artesunate in the published literature, even though mefloquine is associated with blurring of vision, and antimalarials of the quinoline class have been associated with retinopathy (during long term use). While causality is difficult to ascribe in this case, it may be prudent to avoid the use of quinoline-based antimalarials for treating acute malaria in travelers taking mefloquine prophylaxis, because information on the safety of concurrent use of artemisinin combination therapies and mefloquine, or other recommended prophylactic regimens, is limited.

Clinical tolerability of artesunate-amodiaquine versus comparator treatments for uncomplicated falciparum malaria: an individual-patient analysis of eight randomized controlled trials in sub-Saharan Africa

BACKGROUND

The widespread use of artesunate-amodiaquine (ASAQ) for treating uncomplicated malaria makes it important to gather and analyse information on its tolerability.

METHODS

An individual-patient tolerability analysis was conducted using data from eight randomized controlled clinical trials conducted at 17 sites in nine sub-Saharan countries comparing ASAQ to other anti-malarial treatments. All patients who received at least one dose of the study drug were included in the analysis. Differences in adverse event (AE) and treatment emergent adverse event (TEAE) were analysed by Day 28.

RESULTS

Of the 6,179 patients enrolled (74% <5 years of age), 50% (n = 3,113) received ASAQ, 20% (n = 1,217) another ACT, and 30% (n = 1,849) a non-ACT (combination or single-agent) treatment. Overall, 8,542 AEs were recorded. The proportion of patients experiencing at least one gastro-intestinal AE on ASAQ was 43% (and higher than that with artemether-lumefantrine and dihydroartemisinin-piperaquine at two sites), and was 23% for any other AEs (not different from other treatments). Specifically, the risk of diarrhoea, vomiting, cough and weakness was lower with artemether-lumefantrine; artemether-lumefantrine and dihydroartemisinin-piperaquine carried a higher risk of pruritus, chloroquine-SP had a higher risk of nausea. Parasitological recurrence increased the risk of occurrence of any AE. No other difference was detected. Comparing AE to TEAE in patients who had pre-treatment occurrence and grades of intensity recorded, AEs were significantly more related to the pre-treatment prevalence of the symptom (p = 0.001, Fisher test); AEs overestimated TEAEs by a factor ranging from none to five-fold. The overall incidence of serious AEs (SAEs) with ASAQ was nine per 1,000 (29/3,113) and mortality was one per 1,000 (three deaths, none drug-related); both were similar to other treatments.

CONCLUSION

ASAQ was comparatively well-tolerated. Safety information is important, and must be collected and analysed in a standardized way. TEAEs are a more objective measure of treatment-induced toxicity.

Comparing changes in haematologic parameters occurring in patients included in randomized controlled trials of artesunate-amodiaquine vs single and combination treatments of uncomplicated falciparum in sub-Saharan Africa

BACKGROUND

Artesunate-amodiaquine (AS&AQ) is a widely used artemisinin combination therapy (ACT) for falciparum malaria. A comprehensive appreciation of its effects on haematology vs other anti-malarials is needed in view of potential safety liabilities.

METHODS

Individual-patient data analysis conducted on a database from seven randomized controlled trials conducted in sub-Saharan African comparing AS&AQ to reference treatments in uncomplicated falciparum malaria patients of all ages. Haematologic values (white cells total and neutrophil counts, haemoglobin/haematocrit, platelets) were analysed as both continuous and categorical variables for their occurrence, (severity grade 1-4) and changes during follow-up. Risks and trends were calculated using multivariate logistic random effect models.

RESULTS

4,502 patients (72% < 5 years old), from 13 sites in nine countries with 28-day follow-up were treated with AS&AQ (45%) or a comparator (other forms of ACT accounted for 27%, other combination 12%, mono-therapies 16%). Pre-treatment leucopaenia (3%) and neutropaenia (6%) were infrequent; anaemia was common (39%). The treatment-emergent adverse events incidence (TEAE = condition not present or less severe pre-treatment) was 11% for neutropaenia, 6% for thrombocytopaenia with AS&AQ and not different from treatment groups; anaemia was higher with AS&AQ (20%) or other forms of ACT (22%) than in non-artemisinin groups (4%, p = 0.001). Multivariate analysis showed that the risk of anaemia, thrombocytopaenia, and leucopaenia decreased with follow-up time, while neutropaenia increased; the risk of anaemia and thrombocytopaenia increased with higher baseline parasitaemia and parasitological reappearance. White cells total count was not a good surrogate for neutropaenia. No systematic significant difference between treatments was detected. Older patients were at lower risks.

CONCLUSION

The effects of AS&AQ on haematologic parameters were not different from those of other anti-malarial treatments used in sub-Saharan Africa. This analysis provides the basis for a broader evaluation of haematology following anti-malarial treatment. Continuing monitoring of haematologic safety on larger databases is required.

Tolerability and pharmacokinetics of non-fixed and fixed combinations of artesunate and amodiaquine in Malaysian healthy normal volunteers

Objective

There is limited pharmacokinetic data available for the combination artesunate + amodiaquine, which is used widely to treat uncomplicated malaria. This study examines the bioavailability and tolerability of a fixed (200 mg artesunate + 540 mg amodiaquine) and loose (200 mg + 612 mg) combination with a 2×2 cross-over design in 24 healthy volunteers.

Methods

Parent compounds and metabolites [dihydroartemisinin (DHA) and desethylamodiaquine (DEAQ)] were measured by high-performance liquid chromatography–electrochemical detection, and the area under the curve (AUC)_0-t and C_max were compared by an analysis of variance (ANOVA) based on geometric least square means using the Schuirmann two one-sided test.

Results

The AUC_0-t for total DHA and DEAQ were 1522 ± 633 and 30021 ± 14211 ng h/ml for the fixed products and 1688 ± 767 and 40261 ± 19824 ng h/ml (mean ± standard deviation) for the loose products. The ANOVA showed no statistical differences except for sequence effect for DHA. The values obtained with the fixed product were within the 125% bioequivalent limits but extend below the 80% bioequivalence limits.

Conclusion

Both combinations were well tolerated and had comparable pharmacokinetic profiles; differences are unlikely to be clinically relevant.

Electronic supplementary material

The online version of this article (doi:10.1007/s00228-009-0656-1) contains supplementary material, which is available to authorized users.

[Permanent deafness following typhoid fever: case report from Dakar, Senegal]

Severe infections due to Salmonella typhi and Salmonella paratyphi are still common in sub-Saharan Africa where many patients are empirically treated for malaria. In addition to the usual clinical signs and complications of typhoid fever, clinicians practicing in high incidence areas must be aware of less common manifestations. The purpose of this report is to describe a case involving an 18-year-old boy who presented with quinine-resistant febrile coma. The final diagnosis was typhoid fever. After recovery the patient presented complete deafness. Discussion raises the question of whether deafness was secondary to typhoid fever or to drug therapy.

Effects of amodiaquine, artesunate, and artesunate-amodiaquine on Plasmodium falciparum malaria-associated anaemia in children

The effects of amodiaquine, artesunate and artesunate-amodiaquine on Plasmodium falciparum malaria-associated anaemia (PfMAA) and the recovery from PfMAA were evaluated in 328 children with uncomplicated malaria randomized to the standard dose regimens of the three drug treatments. Overall, malaria-attributable fall in haematocrit (MAFH) before treatment was 4.8+/-2.8%, 95% confidence interval (CI) 4.4-5.2%, and was not significantly different between the treatment groups (P=0.31). An age <5 years and a history of illness >3d were independent predictors of MAFH before treatment >4%. Following treatment, drug-attributable fall in haematocrit (DAFH) was significantly higher in amodiaquine-treated children (4.6+/-2.9%, 2.8+/-1.8%, 3.0+/-1.8% for amodiaquine, artesunate, artesunate-amodiaquine, respectively, P<0.0001). The rate of DAFH was significantly lower in artesunate-treated children (1.4+/-0.9%, 0.7+/-0.6%, 1.0+/-0.6% per day for amodiaquine, artesunate and artesunate-amodiaquine, respectively, P<0.0001). The rate of rise in haematocrit from the nadir on days 3-7 was significantly higher in amodiaquine treated children (P=0.045). In anaemic children (n=68), the time elapsing from treatment to the attainment of a haematocrit > or =30%, the anaemia resolution time, and the proportion of anaemic children with complete resolution on day 14 were similar in all treatment groups (P=0.17 and 0.65, respectively). Artemisinin drugs may reduce the extent and rate of fall in PfMAA during treatment and may attenuate malaria-associated anaemia in children.

Pharmacokinetics and tolerability of artesunate and amodiaquine alone and in combination in healthy volunteers

Objectives

The WHO recommends artemisinin-based combination therapies for treatment of uncomplicated falciparum malaria. At least 15 African countries have adopted artesunate plus amodiaquine as treatment policy. As no pharmacokinetic data on this combination have been published to date, we investigated its pharmacokinetic interactions and tolerability in healthy volunteers in Africa.

Methods

In a randomized, three-phase, cross-over study, amodiaquine (10 mg/kg) and artesunate (4 mg/kg) were given as single oral doses to 15 healthy volunteers. Artesunate was given to all volunteers on day 0. On day 7 they received either amodiaquine or amodiaquine plus artesunate and the alternative regimen on day 28. The pharmacokinetics of artesunate and amodiaquine and their main active metabolites dihydroartemisinin and desethylamodiaquine were compared following monotherapy and combination therapy using analysis of variance.

Results

Thirteen volunteers completed the study, and pharmacokinetic parameters could be determined for twelve volunteers. When given in combination, the mean AUC was lower for dihydroartemisinin [ratio 67% (95% CI 51–88%); P = 0.008] and desethylamodiaquine [ratio 65% (95% CI 46–90%); P = 0.015] when compared with monotherapy. Adverse events of concern occurred in four volunteers (27%): grade 3 transaminitis (n = 1), neutropaenia (n = 2), and hypersensitivity (n = 1).

Conclusion

The total drug exposure to both drugs was reduced significantly when they were given in combination. The clinical significance of these interactions is unclear and must be studied in malaria patients. The frequency and nature of adverse events among the healthy volunteers were of concern, and suggest laboratory monitoring would be needed in malaria patients treated with artesunate plus amodiaquine.

Efficacy, safety, and selection of molecular markers of drug resistance by two ACTs in Mali

We conducted a randomized single-blinded trial comparing the efficacy and safety of artesunate (AS) + amodiaquine (AQ, 3 days) versus AS (3 days) + sulfadoxine-pyrimethamine (SP, single dose) versus AS monotherapy (5 days) in Southern Mali. Uncomplicated malaria cases were followed for 28 days. Molecular markers of drug resistance were determined. After identification of recrudescences by genotyping, both artemisinin-based combination therapies (ACTs) reached nearly 100% efficacy at Day 14 and Day 28 versus 98.3% and 96.5% for AS, respectively (P > 0.05). AS + SP significantly selected DHFR and DHPS mutations associated with sulfadoxine and pyrimethamine resistance (P < 0.001), and AS + AQ equally selected PfCRT and PfMDR1 point mutations associated with chloroquine and AQ resistance (P < 0.001). No significant adverse event attributable to any of the study drugs was found. The ACTs were efficacious and safe, but the selection of markers for resistance to the partner drugs raises concerns over their lifespan in areas of intense malaria transmission.

A trial of the efficacy, safety and impact on drug resistance of four drug regimens for seasonal intermittent preventive treatment for malaria in Senegalese children

In the Sahel, most malaria deaths occur among children 1-4 years old during a short transmission season. A trial of seasonal intermittent preventive treatment (IPT) with sulfadoxine-pyrimethamine (SP) and a single dose of artesunate (AS) showed an 86% reduction in the incidence of malaria in Senegal but this may not be the optimum regimen. We compared this regimen with three alternatives.

METHODS

2102 children aged 6-59 months received either one dose of SP plus one dose of AS (SP+1AS) (the previous regimen), one dose of SP plus 3 daily doses of AS (SP+3AS), one dose of SP plus three daily doses of amodiaquine (AQ) (SP+3AQ) or 3 daily doses of AQ and AS (3AQ+3AS). Treatments were given once a month on three occasions during the malaria transmission season. The primary end point was incidence of clinical malaria. Secondary end-points were incidence of adverse events, mean haemoglobin concentration and prevalence of parasites carrying markers of resistance to SP.

FINDINGS

The incidence of malaria, and the prevalence of parasitaemia at the end of the transmission season, were lowest in the group that received SP+3AQ: 10% of children in the group that received SP+1AS had malaria, compared to 9% in the SP+3AS group (hazard ratio HR 0.90, 95%CI 0.60, 1.36); 11% in the 3AQ+3AS group, HR 1.1 (0.76-1.7); and 5% in the SP+3AQ group, HR 0.50 (0.30-0.81). Mutations associated with resistance to SP were present in almost all parasites detected at the end of the transmission season, but the prevalence of Plasmodium falciparum was very low in the SP+3AQ group.

CONCLUSIONS

Monthly treatment with SP+3AQ is a highly effective regimen for seasonal IPT. Choice of this regimen would minimise the spread of drug resistance and allow artemisinins to be reserved for the treatment of acute clinical malaria.

Enhanced efficacy of amodiaquine and chlorpheniramine combination over amodiaquine alone in the treatment of acute uncomplicated Plasmodium falciparum malaria in children

OBJECTIVE

To evaluate the comparative efficacy of amodiaquine (AMQ) alone and the combination of AMQ and chlorpheniramine (CP) in the treatment of acute uncomplicated malaria in children.

SUBJECTS

Of the 110 children enrolled in the study, 103 with acute uncomplicated malaria, aged 6 months to 12 years, were evaluated using the 14-day modification of the WHO field test. The patients were randomized to 2 groups. Group 1 received supervised treatment with AMQ alone (10 mg AMQ base/kg daily for 3 days), while group 2 received supervised treatment with AMQ (same dose as group 1) plus CP (AMQCP) for 7 days.

RESULTS

Both treatment regimens were well tolerated and no patient was withdrawn as a result of recurrent vomiting or drug-related adverse events. There was no significant difference in mean fever and parasite clearance times. The cure rates at day 7 were 90.2 versus 100% (rho = 0.027) for AMQ versus AMQCP, while the day 14 cure rates were 85.9 versus 98.1% for AMQ versus AMQCP, respectively (rho = 0.016).

CONCLUSION

The combination of AMQ plus CP proved significantly more effective than AMQ alone in the treatment of acute uncomplicated falciparum malaria, most probably due to the enhancement of the antimalarial effect of AMQ by CP. The combination of AMQCP could be a better alternative to AMQ alone as a companion drug in artemisinin-based combination therapies.

Emergency liver transplantation in amodiaquine-induced fulminant hepatitis

Amodiaquine is an amino-4-quinoline with the basic spectrum of activity of chloroquine. It has been used widely to treat and prevent malaria. From the mid-1980s, there were reports of fatal adverse drug reactions described in travelers using amodiaquine as antimalarial prophylaxis. In 1990, the World Health Organization (WHO) stopped using this drug in malaria control programs. The WHO Expert Committee on Malaria modified this in 1993 and reported that amodiaquine could be used for treatment if the risk of infection outweighs the potential for adverse drug reactions. Currently, amodiaquine is a potential useful drug, especially if used with artemisinin-based combination therapy and with sulfadoxine-pyrimethamine to improve treatment efficacy for chloroquine-resistant strains of Plasmodium falciparum and P. vivax. We report a case of fulminant hepatitis induced by antimalarial prophylactic use of amodiaquine that necessitated emergency orthotopic liver transplantation.

Efficacy and tolerability of four antimalarial combinations in the treatment of uncomplicated Plasmodium falciparum malaria in Senegal

BACKGROUND

In view of the high level of chloroquine resistance in many countries, WHO has recommended the use of combination therapy with artemisinin derivatives in the treatment of uncomplicated malaria due to Plasmodium falciparum. Four antimalarial drug combinations, artesunate plus amodiaquine (Arsucam), artesunate plus mefloquine (Artequin), artemether plus lumefantrine (Coartem; four doses and six doses), and amodiaquine plus sulphadoxine-pyrimethamine, were studied in five health districts in Senegal.

METHODS

This is a descriptive, analytical, open, randomized study to evaluate the efficacy and tolerability of these four antimalarial combinations in the treatment of uncomplicated falciparum malaria using the 2002 WHO protocol.

RESULTS

All drug combinations demonstrated good efficacy. On day 28, all combinations resulted in an excellent clinical and parasitological response rate of 100% after correction for PCR results, except for the four-dose artemether-lumefantrine regimen (96.4%). Follow-up of approximately 10% of each treatment group on day 42 demonstrated an efficacy of 100%.The combinations were well tolerated clinically and biologically. No unexpected side-effect was observed and all side-effects disappeared at the end of treatment. No serious side-effect requiring premature termination of treatment was observed.

CONCLUSION

The four combinations are effective and well-tolerated.

[Tolerance of amodiaquine]

Amodiaquin is still considered as a poorly tolerated antimalarial causing hematological and hepatic toxicity. In view of complications observed during prophylaxis, the WHO has advised against the use of amodiaquin for prophylaxis as well as treatment. However due to the rapid increase in chloroquine resistance and to the absence of reported cases of toxicity during treatment, the WHO has reconsidered its position and now accepts therapeutic use of amodiaquin under some conditions. It has been demonstrated that amodiaquin activates release of quinoneimine granulocytes causing hematological toxicity. In liver microsomes, metabolism into desethyl derivatives is catalyzed by cytochrome P450 CYP2C8 that has several variant forms with low activity on amodiaquin clearance. Carriers of these variants are at a higher risk for adverse effects. Currently the safety and effectiveness of amodiaquin in association with artesunate has been documented and this therapeutic combination is now recommended for first line treatment of uncomplicated Plasmodium falciparum malaria in 18 African countries.

A randomised trial to assess the safety and efficacy of artemether–lumefantrine (Coartem®) for the treatment of uncomplicated Plasmodium falciparum malaria in Rwanda

Coartem is a fixed-dose combination of artemether-lumefantrine that, given in six doses, provides effective treatment for children with uncomplicated Plasmodium falciparum infection in areas with highly endemic and multidrug-resistant malaria. In Rwanda since 2001, amodiaquine+sulfadoxine-pyrimethamine (AQ+SP) has been the first-line treatment, but resistance to this combination has rapidly emerged and spread. Coartem was considered as a possible alternative, and a randomised, open-label, clinical trial to test its safety, tolerability and efficacy was carried out in 2004-2005. Five hundred children aged 12-59 months with uncomplicated P. falciparum malaria were randomly allocated to AQ+SP or Coartem. Patients were followed up until day 28 after treatment. Adverse events and clinical and parasitological outcomes were recorded. Adequate clinical and parasitological response (ACPR) was significantly higher in children treated with Coartem than in those treated with AQ+SP: the PCR-adjusted 28-day ACPR was 96.68% for Coartem and 79.35% for AQ+SP. Both treatments rapidly cleared parasitaemia and fever, although parasite clearance was significantly faster in children treated with Coartem. Mean packed cell volume increased in all patients, with no significant differences between treatments. Coartem proved to be more efficacious than AQ+SP, with a good safety and tolerability profile.

Efficacies of artesunate plus either sulfadoxine-pyrimethamine or amodiaquine, for the treatment of uncomplicated, Plasmodium falciparum malaria in eastern Sudan

Artemisinin-based combination therapy (ACT) is increasingly being adopted as the first-line treatment for malaria in sub-Saharan Africa. In September-November 2005, in New Halfa, eastern Sudan, the efficacy of artesunate-sulfadoxine-pyrimethamine (AS-SP) for the treatment of uncomplicated, Plasmodium falciparum was compared with that of artesunate-amodiaquine (AS-AQ). The artesunate was given at 4 mg/kg. day on days 0-2, with either a single dose of SP (25 mg sulfadoxine/kg) given on day 0, or AQ, at 10 mg/kg. day, given on days 0-2. Eighty-two of the patients treated (40 given AS-SP and 42 given AS-AQ) completed the 28 days of follow-up. On day 3 all the patients were afebrile and only one patient, in the AS-AQ group, was still parasitaemic. AS-SP appeared slightly more efficacious than AS-AQ but the differences were not statistically significant. Only one patient (2.5%) given AS-SP but four (9.5%) of those given AS-AQ were initially considered to be late treatment and parasitological failures, with all other patients showing an adequate treatment response. The PCR-corrected frequencies of cure were 97.5% for AS-SP and 95.2% for AS-AQ (P>0.05). No gametocytaemias were observed during the follow-up and, although mild adverse effects (nausea, vomiting, abdominal pain, dizziness and/or rash) were detected in 14 patients, they occurred at the same frequency in each treatment arm. It therefore appears that the AS-SP and AS-AQ combinations were both effective and safe for the treatment of uncomplicated, P. falciparum malaria in eastern Sudan.

Dihydroartemisinin-piperaquine versus artesunate-amodiaquine: superior efficacy and posttreatment prophylaxis against multidrug-resistant Plasmodium falciparum and Plasmodium vivax malaria

BACKGROUND

Antimalarial drug resistance is now well established in both Plasmodium falciparum and Plasmodium vivax. In southern Papua, Indonesia, where both strains of plasmodia coexist, we have been conducting a series of studies to optimize treatment strategies.

METHODS

We conducted a randomized trial that compared the efficacy and safety of dihydroartemisinin-piperaquine (DHP) with artesunate-amodiaquine (AAQ). The primary end point was the overall cumulative parasitological failure rate at day 42.

RESULTS

Of the 334 patients in the evaluable patient population, 185 were infected with P. falciparum, 80 were infected with P. vivax, and 69 were infected with both species. The overall parasitological failure rate at day 42 was 45% (95% confidence interval [CI], 36%-53%) for AAQ and 13% (95% CI, 7.2%-19%) for DHP (hazard ratio [HR], 4.3; 95% CI, 2.5-7.2; P<.001). Rates of both recrudescence of P. falciparum infection and recurrence of P. vivax infection were significantly higher after receipt of AAQ than after receipt of DHP (HR, 3.4 [95% CI, 1.2-9.4] and 4.3 [95% CI, 2.2-8.2], respectively; P<.001). By the end of the study, AAQ recipients were 2.95-fold (95% CI, 1.2- to 4.9-fold) more likely to be anemic and 14.5-fold (95% CI, 3.4- to 61-fold) more likely to have carried P. vivax gametocytes.

CONCLUSIONS

DHP was more effective and better tolerated than AAQ against multidrug-resistant P. falciparum and P. vivax infections. The prolonged therapeutic effect of piperaquine delayed the time to P. falciparum reinfection, decreased the rate of recurrence of P. vivax infection, and reduced the risk of P. vivax gametocyte carriage and anemia.

Artemisinin-based combination therapy for uncomplicated Plasmodium falciparum malaria in Colombia

Background

Artemisinin-based combination therapy (ACT) is being widely promoted as a strategy to counteract the increase in Plasmodium falciparum antimalarial drug resistance.

Methods

A randomized, double-blind, placebo-controlled, clinical trial of the efficacy, effect on gametocytes and safety of the addition of artesunate/placebo (4 mg/kg/day × 3 d) to amodiaquine (10 mg/kg/day × 3 d) was conducted in Choco department, a low intensity transmission area in northwest Colombia.

Results

From 2,137 screened subjects, 85 entered the study: 43 in the amodiaquine plus placebo and 42 in the amodiaquine plus artesunate groups. Potentially eligible cases failed to qualify mostly because they were not available for follow-up visits (73%). Based on a per protocol analysis, the therapeutic response to both treatments was high: amodiaquine/placebo 35/36, 97.2% (95% CI 85.5–99.9), and amodiaquine/artesunate 32/32, 100% (89.1–100) after PCR genotyping. The Kaplan-Meier survival estimates based on all eligible patients enrolled (amodiaquine/placebo: n = 42; amodiaquine/artesunate: n = 41) were similar in the two study groups (P = 0.3). The addition of artesunate significantly decreased gametocyte carriage on Day 4 (OR = 0.1 95% CI 0.02–0.6), Day 7 (OR = 0.2 95%CI 0.04–0.9), Day 14 (OR = 0.09 95% CI 0–0.8), and Day 21 (OR95%CI 0–0.9). Most subjects in both groups (81% in amodiaquine/placebo and 75.6% in amodiaquine/artesunate) reported at least one drug related adverse event. Symptoms were generally mild and self-limiting and there was no serious adverse event. Two patients on amodiaquine/artesunate voluntarily withdrew from study because they could not tolerate the medication.

Conclusion

Both drug regimens were effective in this area of Colombia. The addition of artesunate reduced gametocyte carriage and did not adversely affect tolerability. In this set of patients, the rate of adverse events was higher than in other studies. Patients' follow-up is problematic in areas with dispersed population and affects the conduct of clinical studies and monitoring of treatment effects. The results are discussed in the light of concurrent increase resistance to amodiaquine in other endemic areas in Colombia and the factors that may influence a change in the national antimalarial drug policy.

Efficacy, safety, and tolerability of amodiaquine plus sulphadoxine-pyrimethamine used alone or in combination for malaria treatment in pregnancy: a randomised trial

BACKGROUND

The widespread increase in resistance of Plasmodium falciparum to chloroquine and sulphadoxine-pyrimethamine threatens the use of these drugs for malaria treatment in pregnancy. We aimed to assess the safety and efficacy of amodiaquine alone or in combination with sulphadoxine-pyrimethamine as alternative regimens.

METHODS

Pregnant women with a gestational age of 16 weeks or more who attended antenatal clinics at a district hospital in Ghana were screened for malaria with OptiMAL dipsticks. 900 pregnant women who had a positive test result and P falciparum asexual stage parasitaemia were enrolled and randomly assigned chloroquine, sulphadoxine-pyrimethamine, amodiaquine, or amodiaquine plus sulphadoxine-pyrimethamine. The primary outcome was parasitological failure by day 28 of treatment. Women were seen on days 3, 7, 14, and 28 after the start of treatment to assess the effect of treatment on peripheral parasitaemia, haemoglobin concentration, white-blood-cell count, and liver function. Additionally, reports of adverse effects were solicited and monitored during follow-up visits. Analysis was by intention to treat. This trial is registered with the US National Institute of Health clinical trials database number NCT00131703.

FINDINGS

PCR-corrected parasitological failure by day 28 was 14%, 11%, 3%, and 0% in the women assigned chloroquine, sulphadoxine-pyrimethamine, amodiaquine, and amodiaquine plus sulphadoxine-pyrimethamine, respectively (p<0.0001). No serious liver toxic effects or white-blood-cell dyscrasias were noted. Minor side-effects were reported more often on day 3 by women receiving amodiaquine (86%) or amodiaquine plus sulphadoxine-pyrimethamine (90%) than those receiving sulphadoxine-pyrimethamine (48%) or no antimalarial drugs (34%; p<0.0001 for every comparison).

INTERPRETATION

Amodiaquine alone or in combination with sulphadoxine-pyrimethamine, although associated with minor side-effects, is effective when used to treat malaria in pregnancy.

Chloroquine or amodiaquine combined with sulfadoxine-pyrimethamine for uncomplicated malaria: a systematic review

OBJECTIVE

To compare the efficacies against uncomplicated falciparum malaria of chloroquine (CQ), amodiaquine (AQ), sulfadoxine-pyrimethamine (SP) and combinations of these inexpensive drugs.

METHODS

We searched Medline, Embase, Cochrane CENTRAL Register of Controlled Trials, BIOSIS, Web of Science, African Index Medicus, DARE, Digital Dissertations and Current Controlled Trials for randomised or quasi-randomised controlled trials conducted between 1991 and June 2004 regardless of language and geography. We also contacted malaria experts, searched reference lists, and contacted individual authors for unreported study characteristics and additional data. Unpublished data were sought and included in the analyses.

RESULTS

Thirteen randomised trials (n = 4248) were identified and the summary relative risks of treatment failure at 28 days were calculated. There was marginal benefit in adding CQ to SP, compared with SP monotherapy (RR = 0.74, 95% CI 0.54-1.02). Combining AQ with SP was associated with a significantly lower risk of treatment failure than SP monotherapy (RR = 0.35, 95% CI 0.15-0.82) and AQ monotherapy (RR = 0.59, 95% CI 0.42-0.83). AQ plus SP was associated with a significantly lower risk of treatment failure than CQ plus SP (RR = 0.42, 95% CI 0.25-0.72). Serious adverse events were rare and did not increase with combination therapy.

CONCLUSION

Amodiaquine plus SP remains an efficacious, affordable and safe option for treating malaria in certain settings.

Tolerability of amodiaquine and sulphadoxine-pyrimethamine, alone or in combination for the treatment of uncomplicated Plasmodium falciparum malaria in Rwandan adults

OBJECTIVE

To assess the tolerability and efficacy of amodiaquine (AQ)+sulphadoxine-pyrimethamine (SP), the first-line malaria treatment in Rwanda.

METHOD

Randomized, double-blind trial in 2003 in Kigali town. A total of 351 adult patients with uncomplicated Plasmodium falciparum malaria were randomly allocated to one of the following treatments: AQ+SP, AQ or SP. We followed patients until day 14 after treatment and recorded adverse events (AEs) and clinical and parasitological outcomes.

RESULTS

One hundred and eighteen patients reported at least one AE: 40% in the AQ, 39% in the AQ+SP and 21% in the SP groups. The AE was classified as possibly related to the antimalarial treatment for 86 patients. The Risk Ratio for at least one AE after treatment was significantly and about fourfold higher in patients receiving AQ or AQ+SP than in patients receiving SP. Pruritus and fatigue were significantly more frequent in patients treated with AQ or AQ+SP than in those receiving SP. Severe AEs, such as fatigue, nausea, dizziness and vomiting, were observed in four patients treated with AQ, in 10 treated with AQ+SP and in one patient treated with SP.

CONCLUSION

Amodiaquine+SP is not well tolerated and a substantial proportion of patients experienced pruritus and fatigue, thus decreasing their compliance and compromising the first line treatment implementation at national level. This renders AQ-containing regimens sub-optimal; better-tolerated treatments should be identified.

Short communication: high prevalence of the cytochrome P450 2C8*2 mutation in Northern Ghana

Recently, Ghana has changed the first-line treatment of uncomplicated malaria from chloroquine to amodiaquine (AQ) plus artesunate. AQ may cause adverse events such as agranulocytosis and hepatoxicity. The pro-drug AQ is transformed by cytochrome P450 CYP2C8 to the active metabolite N-desethylaminodiaquine. Several polymorphic variants of CYP2C8 are known, some with reduced activity. In 200 randomly selected children from Northern Ghana, we determined the allele frequencies of the CYP2C8 variants CYP2C8*1 (wild type), CYP2C8*2, CYP2C8*3, and CYP2C8*4. We did not detect CYP2C8*3 and CYP2C8*4, but CYP2C8*2 showed an allele frequency of 0.1675. AQ metabolism in patients with CYP2C8*2 may be impaired, and with an increase of AQ based treatment the risk of severe adverse events may mount.

Amodiaquine, sulfadoxine-pyrimethamine, and combination therapy for uncomplicated falciparum malaria: a randomized controlled trial from Burkina Faso

Increasing resistance to chloroquine necessitates the evaluation of other antimalarial therapies in Africa. We compared the efficacies of amodiaquine (AQ), sulfadoxine-pyrimethamine (SP), and AQ + SP for the treatment of uncomplicated falciparum malaria in a randomized trial of patients 6 months of age or older in Bobo-Dioulasso, Burkina Faso. Of the 944 patients enrolled, 829 (88%; 53% under 5 years of age) were assigned 28-day efficacy outcomes. For all regimens, early treatment failures were uncommon (< 2%). Considering all treatment failures based on WHO criteria, AQ + SP was most efficacious (failures in 4.2%), followed by SP (9.1%) and AQ (17.9%; P < 0.02 for all pairwise comparisons). Considering only clinical failures, relative efficacies were similar (failures in 2.1% with AQ + SP, 6.5% with SP, and 13.2% with AQ; P < 0.02 for all pairwise comparisons). The risk of recrudescence was lower with AQ + SP (2.1%) compared with SP (6.1%, P = 0.02) and AQ (8.1%, P = 0.001). Risks of new infection were lower with AQ + SP (2.1%) and SP (2.4%) compared with AQ (9.1%, P < 0.001 for both comparisons). No serious adverse events were seen. AQ + SP appears to offer a highly effective, inexpensive, and available therapy for the treatment of uncomplicated malaria in Burkina Faso.

Open randomized study of artesunate-amodiaquine vs. chloroquine-pyrimethamine-sulfadoxine for the treatment of uncomplicated Plasmodium falciparum malaria in Nigerian children

BACKGROUND

Artemisinin-based combination antimalarials are currently considered effective alternatives for the treatment of malaria in Africa, but there are few studies of such combinations in Nigerian children. We assessed the safety, treatment efficacy and effects on gametocyte carriage of the combination of artesunate plus amodiaquine and chloroquine plus pyrimethamine-sulfadoxine in children.

METHODS

We evaluated 153 children who were aged 12 years or younger who had uncomplicated Plasmodium falciparum malaria. Patients were randomly assigned a combination of artesunate (4 mg/kg of body weight daily for 3 days) plus amodiaquine (30 mg/kg over 3 days), or chloroquine (25 mg/kg over 3 days) plus pyrimethamine-sulfadoxine (25 mg/kg of the sulfadoxine component at presentation). The primary endpoints were the proportions of children with adequate clinical and parasitological response, late parasitological failure, late clinical failure and early treatment failure. The parasitological cure rates on days 14-28 were also used as the primary endpoints.

RESULTS

Both regimens were well tolerated; no child was withdrawn because of drug intolerance. All children treated with artesunate plus amodiaquine had adequate clinical and parasitological response (ACPR), while all but five children treated with chloroquine plus pyrimethamine-sulfadoxine had similar response. Fever clearance times were similar in the two treatment groups. However, the proportion of patients whose parasitaemia cleared by day 2 was significantly higher (100 vs. 50%, P = 0.00001) and parasite clearance was significantly faster (1.7 +/- 0.4 vs. 2.5 +/- 0.8 days, P = 0.0001) in children treated with artesunate plus amodiaquine. The cure rates on days 21 (100%vs. 94%, P = 0.03) and 28 (100%vs. 90%, P = 0.003) were also significantly higher in children treated with artesunate plus amodiaquine than in those treated with chloroquine plus pyrimethamine-sulfadoxine. Overall, a significantly higher proportion of children treated with chloroquine plus pyrimethamine-sulfadoxine carried gametocytes at least once during follow-up compared with those treated with artesunate plus amodiaquine [5 of 50 (10%) vs. 1 of 103 (0.97%), P = 0.01].

CONCLUSION

The combination of artesunate plus amodiaquine is therapeutically superior to a combination of chloroquine plus pyrimethamine-sulfadoxine, and significantly reduced gametocyte carriage following treatment.

Antimalarial drugs: QT prolongation and cardiac arrhythmias

Most available antimalarial drugs induce cardiac side effects. These side effects include various mild heart rate changes (amodiaquine) to excessive prolongation of the QT interval (halofantrine) which may lead to lethal arrhythmias such as Torsade de Pointes (TdP). The cellular mechanism of such events during antimalarial therapy is principally related to ion channel inhibition (e.g., human ether-a-go-go related gene channel) which may slow the repolarisation process and create a good substrate for arrhythmia (when dispersion of repolarisation is present). However, other antimalarial drugs do not show as potent cardiac side effects, like co-arthemeter and sulfadoxine-pyrimethamine. Considering that TdP are favoured by a complex combination of electrophysiological changes, a predictive cardiosafety strategy for new antimalarial drugs should comprise assays with an increasing level of information from ion channel level, cellular and organ level, to the whole organism. In this review, the actual knowledge on underlying mechanisms of QT prolongation and TdP is described, followed by the cardiac safety profiles of present antimalarial drugs.

Sulfadoxine-pyrimethamine plus chloroquine or amodiaquine for uncomplicated falciparum malaria: a randomized, multisite trial to guide national policy in Uganda

The use of combinations of inexpensive drugs for the treatment of malaria in Africa has been proposed as an interim policy while awaiting the widespread availability of more effective regimens. We compared sulfadoxine-pyrimethamine plus chloroquine or amodiaquine in three districts in Uganda. Patients aged 6 months or greater with uncomplicated falciparum malaria were enrolled and randomized to therapy. Safety, tolerability, and efficacy outcomes, adjusted by genotyping, were assessed over 28 days. Of 1,105 patients enrolled, 1,057 (96%) completed follow-up. For children less than 5 years old, the risk of clinical treatment failure adjusted by genotyping at the three sites ranged from 34% to 67% with chloroquine plus sulfadoxine-pyrimethamine and from 13% to 35% with amodiaquine plus sulfadoxine-pyrimethamine (risk differences 21-32%, P < 0.0001 at all sites). Serious adverse events were uncommon with both regimens. The risk of treatment failure with chloroquine plus sulfadoxine-pyrimethamine, the current standard in Uganda, was unacceptably high. Amodiaquine plus sulfadoxine-pyrimethamine was significantly more efficacious; however, existing levels of resistance raises concern about the useful therapeutic life-span of this regimen.