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Abstract Background Malaria in Zambia remains a public health and developmental challenge, affecting mostly children under five and pregnant women. In 2002, the first-line treatment for uncomplicated malaria was changed to artemether-lumefantrine (AL) that has proved to be highly efficacious against multidrug resistant Plasmodium falciparum. Objective The study objective was to determine whether dihydroartemisinin-piperaquine (DHA/PQP) had similar efficacy, safety and tolerability as AL for the treatment of children with uncomplicated P. falciparum malaria in Ndola, Zambia. Methods Between 2005 and 2006, 304 children (6-59 months old) with uncomplicated P. falciparum were enrolled, randomized to AL (101) or DHA/PQP (203) and followed up for 42 days. Outcome of treatment was defined according to the standard WHO classification, i.e. early treatment failure (ETF), late clinical failure (LCF, late parasitological failure (LPF) and adequate clinical and parasitological response (ACPR). Recurrent infections were genotyped to distinguish between recrudescence and new infection. Results No ETF was observed. At day 28, PCR-uncorrected ACPR was 92% in the DHA/PQP and 74% in the AL arm (OR: 4.05; 95%CI: 1.89-8.74; p < 0.001). Most failure were new infections and PCR-corrected ACPR was similar in the two study arms (OR: 0.69; 95%CI: 0.22-2.26; p = 0.33). Similar results were observed for day 42, i.e. higher PCR-uncorrected ACPR for DHA/PQP, mainly due to the difference observed up to day 28, while the PCR-corrected ACPR was similar: DHA/PQP: 93% (179/192), AL: 93% (84/90), (OR: 0.92; 95%CI: 0.30-2.64; p = 0.85). Except for cough, more frequent in the DHA/PQP arm (p = 0.04), there were no differences between treatment arms in the occurrence of adverse events. Two serious adverse events were probably associated to AL treatment. Conclusion DHA/PQP was as efficacious, safe and well tolerated in treatment of uncomplicated malaria as AL, though in the latter group more new infections during the follow up were observed. DHA/PQP seems a potential candidate to be used as an alternative first-line or rescue treatment in Zambia. Trial Registration ISRCTN16263443, at http://www.controlled-trials.com/isrctn

Artemisinin-based combination therapy (ACT) is the first-line recommended treatment for uncomplicated malaria. Pharmacokinetic (PK) properties in pregnant women are often based on small studies and need to be confirmed and validated in larger pregnant patient populations. This study aimed to evaluate the PK properties of amodiaquine and its active metabolite, desethylamodiaquine, and piperaquine in women in their second and third trimester of pregnancy with uncomplicated P. falciparum infections. Eligible pregnant women received either artesunate-amodiaquine (200/540 mg daily, n = 771) or dihydroartemisinin-piperaquine (40/960 mg daily, n = 755) for 3 days (NCT00852423). Population PK properties were evaluated using nonlinear mixed-effects modeling, and effect of gestational age and trimester was evaluated as covariates. 1071 amodiaquine and 1087 desethylamodiaquine plasma concentrations, and 976 piperaquine plasma concentrations, were included in the population PK analysis. Amodiaquine concentrations were described accurately with a one-compartment disposition model followed by a two-compartment disposition model of desethylamodiaquine. The relative bioavailability of amodiaquine increased with gestational age (1.25% per week). The predicted exposure to desethylamodiaquine was 2.8%-32.2% higher in pregnant women than that reported in non-pregnant women, while day 7 concentrations were comparable. Piperaquine concentrations were adequately described by a three-compartment disposition model. Neither gestational age nor trimester had significant impact on the PK of piperaquine. The predicted exposure and day 7 concentrations of piperaquine were similar to that reported in non-pregnant women. In conclusion, the exposure to desethylamodiaquine and piperaquine was similar to that in non-pregnant women. Dose adjustment is not warranted for women in their second and their trimester of pregnancy., (© 2024 The Author(s). CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals LLC on behalf of American Society for Clinical Pharmacology and Therapeutics.)

Background: Malaria in pregnancy affects both the mother and the fetus. However, evidence supporting treatment guidelines for uncomplicated (including asymptomatic) falciparum malaria in pregnant women is scarce and assessed in varied ways. We did a systematic literature review and individual patient data (IPD) meta-analysis to compare the efficacy and tolerability of different artemisinin-based or quinine-based treatments for malaria in pregnant women., Methods: We did a systematic review of interventional or observational cohort studies assessing the efficacy of artemisinin-based or quinine-based treatments in pregnancy. Seven databases (MEDLINE, Embase, Global Health, Cochrane Library, Scopus, Web of Science, and Literatura Latino Americana em Ciencias da Saude) and two clinical trial registries (International Clinical Trials Registry Platform and ClinicalTrials.gov) were searched. The final search was done on April 26, 2019. Studies that assessed PCR-corrected treatment efficacy in pregnancy with follow-up of 28 days or more were included. Investigators of identified studies were invited to share data from individual patients. The outcomes assessed included PCR-corrected efficacy, PCR-uncorrected efficacy, parasite clearance, fever clearance, gametocyte development, and acute adverse events. One-stage IPD meta-analysis using Cox and logistic regression with random-effects was done to estimate the risk factors associated with PCR-corrected treatment failure, using artemether-lumefantrine as the reference. This study is registered with PROSPERO, CRD42018104013., Findings: Of the 30 studies assessed, 19 were included, representing 92% of patients in the literature (4968 of 5360 episodes). Risk of PCR-corrected treatment failure was higher for the quinine monotherapy (n=244, adjusted hazard ratio [aHR] 6·11, 95% CI 2·57-14·54, p<0·0001) but lower for artesunate-amodiaquine (n=840, 0·27, 95% 0·14-0·52, p<0·0001), artesunate-mefloquine (n=1028, 0·56, 95% 0·34-0·94, p=0·03), and dihydroartemisinin-piperaquine (n=872, 0·35, 95% CI 0·18-0·68, p=0·002) than artemether-lumefantrine (n=1278) after adjustment for baseline asexual parasitaemia and parity. The risk of gametocyte carriage on day 7 was higher after quinine-based therapy than artemisinin-based treatment (adjusted odds ratio [OR] 7·38, 95% CI 2·29-23·82)., Interpretation: Efficacy and tolerability of artemisinin-based combination therapies (ACTs) in pregnant women are better than quinine. The lower efficacy of artemether-lumefantrine compared with other ACTs might require dose optimisation., Funding: The Bill & Melinda Gates Foundation, ExxonMobil Foundation, and the University of Oxford Clarendon Fund., (Copyright © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Background: Malaria in pregnancy, including asymptomatic infection, has a detrimental impact on foetal development. Individual patient data (IPD) meta-analysis was conducted to compare the association between antimalarial treatments and adverse pregnancy outcomes, including placental malaria, accompanied with the gestational age at diagnosis of uncomplicated falciparum malaria infection., Methods: A systematic review and one-stage IPD meta-analysis of studies assessing the efficacy of artemisinin-based and quinine-based treatments for patent microscopic uncomplicated falciparum malaria infection (hereinafter uncomplicated falciparum malaria) in pregnancy was conducted. The risks of stillbirth (pregnancy loss at ≥ 28.0 weeks of gestation), moderate to late preterm birth (PTB, live birth between 32.0 and < 37.0 weeks), small for gestational age (SGA, birthweight of < 10th percentile), and placental malaria (defined as deposition of malaria pigment in the placenta with or without parasites) after different treatments of uncomplicated falciparum malaria were assessed by mixed-effects logistic regression, using artemether-lumefantrine, the most used antimalarial, as the reference standard. Registration PROSPERO: CRD42018104013., Results: Of the 22 eligible studies (n = 5015), IPD from16 studies were shared, representing 95.0% (n = 4765) of the women enrolled in literature. Malaria treatment in this pooled analysis mostly occurred in the second (68.4%, 3064/4501) or third trimester (31.6%, 1421/4501), with gestational age confirmed by ultrasound in 91.5% (4120/4503). Quinine (n = 184) and five commonly used artemisinin-based combination therapies (ACTs) were included: artemether-lumefantrine (n = 1087), artesunate-amodiaquine (n = 775), artesunate-mefloquine (n = 965), and dihydroartemisinin-piperaquine (n = 837). The overall pooled proportion of stillbirth was 1.1% (84/4361), PTB 10.0% (619/4131), SGA 32.3% (1007/3707), and placental malaria 80.1% (2543/3035), and there were no significant differences of considered outcomes by ACT. Higher parasitaemia before treatment was associated with a higher risk of SGA (adjusted odds ratio [aOR] 1.14 per 10-fold increase, 95% confidence interval [CI] 1.03 to 1.26, p = 0.009) and deposition of malaria pigment in the placenta (aOR 1.67 per 10-fold increase, 95% CI 1.42 to 1.96, p < 0.001)., Conclusions: The risks of stillbirth, PTB, SGA, and placental malaria were not different between the commonly used ACTs. The risk of SGA was high among pregnant women infected with falciparum malaria despite treatment with highly effective drugs. Reduction of malaria-associated adverse birth outcomes requires effective prevention in pregnant women.

Background: The World Health Organization (WHO) recommendation of treating uncomplicated malaria during the second and third trimester of pregnancy with an artemisinin-based combination therapy (ACT) has already been implemented by all sub-Saharan African countries. However, there is limited knowledge on the effect of ACT on pregnancy outcomes, and on newborn and infant's health., Methods: Pregnant women with malaria in four countries (Burkina Faso, Ghana, Malawi and Zambia) were treated with either artemether-lumefantrine (AL), amodiaquine-artesunate (ASAQ), mefloquine-artesunate (MQAS), or dihydroartemisinin-piperaquine (DHA-PQ); 3127 live new-borns (822 in the AL, 775 in the ASAQ, 765 in the MQAS and 765 in the DHAPQ arms) were followed-up until their first birthday., Results: Prevalence of placental malaria and low birth weight were 28.0% (738/2646) and 16.0% (480/2999), respectively, with no significant differences between treatment arms. No differences in congenital malformations (p = 0.35), perinatal mortality (p = 0.77), neonatal mortality (p = 0.21), and infant mortality (p = 0.96) were found., Conclusions: Outcome of pregnancy and infant survival were similar between treatment arms indicating that any of the four artemisinin-based combinations could be safely used during the second and third trimester of pregnancy without any adverse effect on the baby. Nevertheless, smaller safety differences between artemisinin-based combinations cannot be excluded; country-wide post-marketing surveillance would be very helpful to confirm such findings. Trial registration ClinicalTrials.gov, NCT00852423, Registered on 27 February 2009, https://clinicaltrials.gov/ct2/show/NCT00852423.

Background: Determining gestational age in resource-poor settings is challenging because of limited availability of ultrasound technology and late first presentation to antenatal clinic. Last menstrual period (LMP), symphysio-pubis fundal height (SFH) and Ballard Score (BS) at delivery are therefore often used. We assessed the accuracy of LMP, SFH, and BS to estimate gestational age at delivery and preterm birth compared to ultrasound (US) using a large dataset derived from a randomized controlled trial in pregnant malaria patients in four African countries., Methods: Mean and median gestational age for US, LMP, SFH and BS were calculated for the entire study population and stratified by country. Correlation coefficients were calculated using Pearson's rho, and Bland Altman plots were used to calculate mean differences in findings with 95% limit of agreements. Sensitivity, specificity, positive predictive value and negative predictive value were calculated considering US as reference method to identify term and preterm babies., Results: A total of 1630 women with P. falciparum infection and a gestational age > 24 weeks determined by ultrasound at enrolment were included in the analysis. The mean gestational age at delivery using US was 38.7 weeks (95%CI: 38.6-38.8), by LMP, 38.4 weeks (95%CI: 38.0-38.9), by SFH, 38.3 weeks (95%CI: 38.2-38.5), and by BS 38.0 weeks (95%CI: 37.9-38.1) (p < 0.001). Correlation between US and any of the other three methods was poor to moderate. Sensitivity and specificity to determine prematurity were 0.63 (95%CI 0.50-0.75) and 0.72 (95%CI, 0.66-0.76) for LMP, 0.80 (95%CI 0.74-0.85) and 0.74 (95%CI 0.72-0.76) for SFH and 0.42 (95%CI 0.35-0.49) and 0.77 (95%CI 0.74-0.79) for BS., Conclusions: In settings with limited access to ultrasound, and in women who had been treated with P. falciparum malaria, SFH may be the most useful antenatal tool to date a pregnancy when women present first in second and third trimester. The Ballard postnatal maturation assessment has a limited role and lacks precision. Improving ultrasound facilities and skills, and early attendance, together with the development of new technologies such as automated image analysis and new postnatal methods to assess gestational age, are essential for the study and management of preterm birth in low-income settings.

Background: In Zambia, malaria is one of the leading causes of morbidity and mortality, especially among under five children and pregnant women. For the latter, the World Health Organization recommends the use of artemisinin-based combination therapy (ACT) in the second and third trimester of pregnancy. In a context of limited information on ACT, the safety and efficacy of three combinations, namely artemether-lumefantrine (AL), mefloquine-artesunate (MQAS) and dihydroartemisinin-piperaquine (DHAPQ) were assessed in pregnant women with malaria., Methods: The trial was carried out between July 2010 and August 2013 in Nchelenge district, Luapula Province, an area of high transmission, as part of a multi-centre trial. Women in the second or third trimester of pregnancy and with malaria were recruited and randomized to one of the three study arms. Women were actively followed up for 63 days, and then at delivery and 1 year post-delivery., Results: Nine hundred pregnant women were included, 300 per arm. PCR-adjusted treatment failure was 4.7% (12/258) (95% CI 2.7-8.0) for AL, 1.3% (3/235) (95% CI 0.4-3.7) for MQAS and 0.8% (2/236) (95% CI 0.2-3.0) for DHAPQ, with significant risk difference between AL and DHAPQ (p = 0.01) and between AL and MQAS (p = 0.03) treatments. Re-infections during follow up were more frequent in the AL (HR: 4.71; 95% CI 3.10-7.2; p < 0.01) and MQAS (HR: 1.59; 95% CI 1.02-2.46; p = 0.04) arms compared to the DHAPQ arm. PCR-adjusted treatment failure was significantly associated with women under 20 years [Hazard Ratio (HR) 5.35 (95% CI 1.07-26.73; p = 0.04)] and higher malaria parasite density [3.23 (95% CI 1.03-10.10; p = 0.04)], and still women under 20 years [1.78, (95% CI 1.26-2.52; p < 0.01)] had a significantly higher risk of re-infection. The three treatments were generally well tolerated. Dizziness, nausea, vomiting, headache and asthenia as adverse events (AEs) were more common in MQAS than in AL or DHAPQ (p < 0.001). Birth outcomes were not significantly different between treatment arms., Conclusion: As new infections can be prevented by a long acting partner drug to the artemisinins, DHAPQ should be preferred in places as Nchelenge district where transmission is intense while in areas of low transmission intensity AL or MQAS may be used.

Background: Plasmodium falciparum resistance to anti-malarial drugs remains a major obstacle to malaria control and elimination. The parasite has developed resistance to every anti-malarial drug introduced for wide-scale treatment. However, the spread of resistance may be reversible. Malawi was the first country to discontinue chloroquine use due to widespread resistance. Within a decade of the removal of drug pressure, the molecular marker of chloroquine-resistant malaria had disappeared and the drug was shown to have excellent clinical efficacy. Many countries have observed decreases in the prevalence of chloroquine resistance with the discontinuation of chloroquine use. In Zambia, chloroquine was used as first-line treatment for uncomplicated malaria until treatment failures led the Ministry of Health to replace it with artemether-lumefantrine in 2003. Specimens from a recent study were analysed to evaluate prevalence of chloroquine-resistant malaria in Nchelenge district a decade after chloroquine use was discontinued., Methods: Parasite DNA was extracted from dried blood spots collected by finger-prick in pregnant women who were enrolling in a clinical trial. The specimens underwent pyrosequencing to determine the genotype of the P. falciparum chloroquine resistance transporter, the gene that is associated with CQ resistance., Results: Three-hundred and two specimens were successfully analysed. No chloroquine-resistant genotypes were detected., Conclusion: The study found the disappearance of chloroquine-resistant malaria after the removal of chloroquine drug pressure. Chloroquine may have a role for malaria prevention or treatment in Zambia and throughout the region in the future.

Background: Information regarding the safety and efficacy of artemisinin combination treatments for malaria in pregnant women is limited, particularly among women who live in sub-Saharan Africa., Methods: We conducted a multicenter, randomized, open-label trial of treatments for malaria in pregnant women in four African countries. A total of 3428 pregnant women in the second or third trimester who had falciparum malaria (at any parasite density and regardless of symptoms) were treated with artemether-lumefantrine, amodiaquine-artesunate, mefloquine-artesunate, or dihydroartemisinin-piperaquine. The primary end points were the polymerase-chain-reaction (PCR)-adjusted cure rates (i.e., cure of the original infection; new infections during follow-up were not considered to be treatment failures) at day 63 and safety outcomes., Results: The PCR-adjusted cure rates in the per-protocol analysis were 94.8% in the artemether-lumefantrine group, 98.5% in the amodiaquine-artesunate group, 99.2% in the dihydroartemisinin-piperaquine group, and 96.8% in the mefloquine-artesunate group; the PCR-adjusted cure rates in the intention-to-treat analysis were 94.2%, 96.9%, 98.0%, and 95.5%, respectively. There was no significant difference among the amodiaquine-artesunate group, dihydroartemisinin-piperaquine group, and the mefloquine-artesunate group. The cure rate in the artemether-lumefantrine group was significantly lower than that in the other three groups, although the absolute difference was within the 5-percentage-point margin for equivalence. The unadjusted cure rates, used as a measure of the post-treatment prophylactic effect, were significantly lower in the artemether-lumefantrine group (52.5%) than in groups that received amodiaquine-artesunate (82.3%), dihydroartemisinin-piperaquine (86.9%), or mefloquine-artesunate (73.8%). No significant difference in the rate of serious adverse events and in birth outcomes was found among the treatment groups. Drug-related adverse events such as asthenia, poor appetite, dizziness, nausea, and vomiting occurred significantly more frequently in the mefloquine-artesunate group (50.6%) and the amodiaquine-artesunate group (48.5%) than in the dihydroartemisinin-piperaquine group (20.6%) and the artemether-lumefantrine group (11.5%) (P<0.001 for comparison among the four groups)., Conclusions: Artemether-lumefantrine was associated with the fewest adverse effects and with acceptable cure rates but provided the shortest posttreatment prophylaxis, whereas dihydroartemisinin-piperaquine had the best efficacy and an acceptable safety profile. (Funded by the European and Developing Countries Clinical Trials Partnership and others; ClinicalTrials.gov number, NCT00852423.).

Background: Recent gains in reducing the global burden of malaria are threatened by the emergence of Plasmodium falciparum resistance to artemisinins. The discovery that mutations in portions of a P. falciparum gene encoding kelch (K13)-propeller domains are the major determinant of resistance has provided opportunities for monitoring such resistance on a global scale., Methods: We analyzed the K13-propeller sequence polymorphism in 14,037 samples collected in 59 countries in which malaria is endemic. Most of the samples (84.5%) were obtained from patients who were treated at sentinel sites used for nationwide surveillance of antimalarial resistance. We evaluated the emergence and dissemination of mutations by haplotyping neighboring loci., Results: We identified 108 nonsynonymous K13 mutations, which showed marked geographic disparity in their frequency and distribution. In Asia, 36.5% of the K13 mutations were distributed within two areas--one in Cambodia, Vietnam, and Laos and the other in western Thailand, Myanmar, and China--with no overlap. In Africa, we observed a broad array of rare nonsynonymous mutations that were not associated with delayed parasite clearance. The gene-edited Dd2 transgenic line with the A578S mutation, which expresses the most frequently observed African allele, was found to be susceptible to artemisinin in vitro on a ring-stage survival assay., Conclusions: No evidence of artemisinin resistance was found outside Southeast Asia and China, where resistance-associated K13 mutations were confined. The common African A578S allele was not associated with clinical or in vitro resistance to artemisinin, and many African mutations appear to be neutral. (Funded by Institut Pasteur Paris and others.).

Background: Artesunate-amodiaquine (AS-AQ) is one of the most widely used artemisinin-based combination therapies (ACTs) to treat uncomplicated Plasmodium falciparum malaria in Africa. We investigated the impact of different dosing strategies on the efficacy of this combination for the treatment of falciparum malaria., Methods: Individual patient data from AS-AQ clinical trials were pooled using the WorldWide Antimalarial Resistance Network (WWARN) standardised methodology. Risk factors for treatment failure were identified using a Cox regression model with shared frailty across study sites., Results: Forty-three studies representing 9,106 treatments from 1999-2012 were included in the analysis; 4,138 (45.4%) treatments were with a fixed dose combination with an AQ target dose of 30 mg/kg (FDC), 1,293 (14.2%) with a non-fixed dose combination with an AQ target dose of 25 mg/kg (loose NFDC-25), 2,418 (26.6%) with a non-fixed dose combination with an AQ target dose of 30 mg/kg (loose NFDC-30), and the remaining 1,257 (13.8%) with a co-blistered non-fixed dose combination with an AQ target dose of 30 mg/kg (co-blistered NFDC). The median dose of AQ administered was 32.1 mg/kg [IQR: 25.9-38.2], the highest dose being administered to patients treated with co-blistered NFDC (median = 35.3 mg/kg [IQR: 30.6-43.7]) and the lowest to those treated with loose NFDC-25 (median = 25.0 mg/kg [IQR: 22.7-25.0]). Patients treated with FDC received a median dose of 32.4 mg/kg [IQR: 27-39.0]. After adjusting for reinfections, the corrected antimalarial efficacy on day 28 after treatment was similar for co-blistered NFDC (97.9% [95% confidence interval (CI): 97.0-98.8%]) and FDC (98.1% [95% CI: 97.6%-98.5%]; P = 0.799), but significantly lower for the loose NFDC-25 (93.4% [95% CI: 91.9%-94.9%]), and loose NFDC-30 (95.0% [95% CI: 94.1%-95.9%]) (P < 0.001 for all comparisons). After controlling for age, AQ dose, baseline parasitemia and region; treatment with loose NFDC-25 was associated with a 3.5-fold greater risk of recrudescence by day 28 (adjusted hazard ratio, AHR = 3.51 [95% CI: 2.02-6.12], P < 0.001) compared to FDC, and treatment with loose NFDC-30 was associated with a higher risk of recrudescence at only three sites., Conclusions: There was substantial variation in the total dose of amodiaquine administered in different AS-AQ combination regimens. Fixed dose AS-AQ combinations ensure optimal dosing and provide higher antimalarial treatment efficacy than the loose individual tablets in all age categories.

Background: Intermittent preventive treatment of malaria in pregnancy (IPTp) with sulphadoxine-pyrimethamine (SP) decreases placental parasitaemia, thus improving birth outcomes. Zambian policy recommends monthly SP-IPTp doses given presumptively during pregnancy at each antenatal examination, spaced one month apart after 16 weeks of gestation. The effectiveness of SP-IPTp was evaluated in Zambia where a recent study showed moderate prevalence of Plasmodium falciparum parasites with genetic mutations that confer SP resistance., Methods: HIV-negative women were enrolled at the time of delivery at two facilities in Mansa, Zambia, an area of high malaria transmission. Women were interviewed and SP exposure was determined by antenatal card documentation or self-reports. Using Poisson regression modelling, the effectiveness of SP-IPTp was evaluated for outcomes of parasitaemia (microscopic examination of maternal peripheral, cord, and placental blood films), maternal anaemia (Hb < 11 g/dl), placental infection (histopathology), and infant outcomes (low birth weight (LBW), preterm delivery, and small for gestational age) in women who took 0-4 doses of SP-IPTp., Results: Participants included 435 women, with a median age of 23 years (range 16-44). Thirty-four women took zero doses of SP-IPTp, while 115, 142 and 144 women took one, two, or ≥ three doses, respectively. Multivariate Poisson regression models considering age, mosquito net usage, indoor residual spraying, urban home, gravidity, facility, wet season delivery, and marital status showed that among paucigravid women ≥ two doses of SP-ITPp compared to one or less doses was associated with a protective effect on LBW (prevalence ratio (PR) 0.33, 95% confidence interval (CI) 0.12-0.91) and any infection (PR 0.76, CI 0.58-0.99). Multivariate models considering SP-IPTp as a continuous variable showed a protective dose-response association with LBW (paucigravid women: PR 0.54, CI 0.33-0.90, multigravid women: PR 0.63, CI 0.41-0.97)., Conclusions: In Mansa, Zambia, an area of moderate SP resistance, ≥ two doses of SP-IPTp were associated with a protective effect from malaria in pregnancy, especially among paucigravid women. Each dose of SP-IPTp contributed to a 46 and 37% decrease in the frequency of LBW among paucigravid and multigravid women, respectively. SP-IPTp remains a viable strategy in this context.

Background: Asymptomatic and symptomatic malaria during pregnancy has consequences for both mother and her offspring. Unfortunately, there is insufficient information on the safety and efficacy of most antimalarials in pregnancy. Indeed, clinical trials assessing antimalarial treatments systematically exclude pregnancy for fear of teratogenicity and embryotoxicity. The little available information originates from South East Asia while in sub-Saharan Africa such information is still limited and needs to be provided., Design: A Phase 3, non-inferiority, multicentre, randomized, open-label clinical trial on safety and efficacy of 4 ACT when administered during pregnancy was carried out in 4 African countries: Burkina Faso, Ghana, Malawi and Zambia. This is a four arm trial using a balanced incomplete block design. Pregnant women diagnosed with malaria are randomised to receive either amodiaquine-artesunate (AQ-AS), dihydroartemisinin-piperaquine (DHA-PQ), artemether-lumefantrine (AL), or mefloquine-artesunate (MQAS). They are actively followed up until day 63 post-treatment and then monthly until 4-6 weeks post-delivery. The offspring is visited at the time of the first birthday. The primary endpoint is treatment failure (PCR adjusted) at day 63 and safety profiles. Secondary endpoints included PCR unadjusted treatment failure up to day 63, gametocyte carriage, Hb changes, placenta malaria, mean birth weight and low birth weight. The primary statistical analysis will use the combined data from all 4 centres, with adjustment for any centre effects, using an additive model for the response rates. This will allow the assessment of all 6 possible pair-wise treatment comparisons using all available data., Discussion: The strength of this trial is the involvement of several African countries, increasing the generalisability of the results. In addition, it assesses most ACTs currently available, determining their relative '-value-' compared to others. The balanced incomplete block design was chosen because using all 4-arms in each site would have increased complexity in terms of implementation. Excluding HIV-positive pregnant women on antiretroviral drugs may be seen as a limitation because of the possible interactions between antiretroviral and antimalarial treatments. Nevertheless, the results of this trial will provide the evidence base for the formulation of malaria treatment policy for pregnant women in sub-Saharan Africa.

Background: Intermittent preventive treatment of malaria in pregnancy (IPTp) with sulphadoxine-pyrimethamine (SP) decreases adverse effects of malaria during pregnancy. Zambia implemented its IPTp-SP programme in 2003. Emergence of SP-resistant Plasmodium falciparum threatens this strategy. The quintuple mutant haplotype (substitutions in N51I, C59R, S108N in dhfr and A437G and K540E in dhps genes), is associated with SP treatment failure in non-pregnant patients with malaria. This study examined efficacy of IPTp-SP and presence of the quintuple mutant among pregnant women in Mansa, Zambia., Methods: In Mansa, an area with high malaria transmission, HIV-negative pregnant women presenting to two antenatal clinics for the 1st dose of IPTp-SP with asymptomatic parasitaemia were enrolled and microscopy for parasitaemia was done weekly for five weeks. Outcomes were parasitological failure and adequate parasitological response (no parasitaemia during follow-up). Polymerase chain reaction assays were employed to distinguish recrudescence from reinfection, and identify molecular markers of SP resistance. Survival analysis included those who had reinfection and incomplete follow-up (missed at least one follow-up)., Results: Of the 109 women included in the study, 58 (53%) completed all follow-up, 34 (31%) had incomplete follow-up, and 17 (16%) were lost to follow-up after day 0. Of those who had complete follow-up, 15 (26%, 95% confidence interval [CI] [16-38]) had parasitological failure. For the 92 women included in the survival analysis, median age was 20 years (interquartile range [IQR] 18-22), median gestational age was 22 weeks (IQR range 20-24), and 57% were primigravid. There was no difference in time to failure in primigravid versus multigravid women. Of the 84 women with complete haplotype data for the aforementioned loci of the dhfr and dhps genes, 53 (63%, 95% CI [50-70]) had quintuple mutants (two with an additional mutation in A581G of dhps). Among women with complete follow-up and quintuple mutants, 22% had parasitological failure versus 0% without (p = 0.44)., Conclusions: While underpowered, this study found 26% failure rates of SP given the moderate prevalence of the quintuple mutant haplotype. Despite the presence of resistance, SP retained some efficacy in clearing parasites in pregnant women, and may remain a viable option for IPTp in Zambia.

Background: Malaria is considered as one of the major public health problems and among the diseases of poverty. In areas of stable and relatively high transmission, pregnant women and their newborn babies are among the higher risk groups. A multicentre trial on the safety and efficacy of several formulations of artemisinin-based combination therapy (ACT) during pregnancy is currently on-going in four African countries, including Zambia, whose study site is in Nchelenge district. As the study outcomes may be influenced by the local malaria endemicity, this needs to be characterized. A cross-sectional survey to determine the prevalence and intensity of infection among <10 years old was carried out in March-April 2012 in Nchelenge district., Methods: The sampling unit was the household where all children < 10 years of age were included in the survey using simple random household selection on a GPS coded list. A blood sample for determining haemoglobin concentration and identifying malaria infection was collected from each recruited child., Results: Six hundred thirty households were selected and 782 children tested for malaria and anaemia. Prevalence of malaria infection was 30.2% (236/782), the large majority (97.9%, 231/236) being Plasmodium falciparum and the remaining ones (2.1%, 5/236) Plasmodium malariae. Anaemia, defined as haemoglobin concentration <11 g/dl, was detected in 51.2% (398/782) children., Conclusion: In Zambia, despite the reported decline in malaria burden, pockets of high malaria endemicity, such as Nchelenge district, still remain. This is a border area and significant progress can be achieved only by concerted efforts aimed at increasing coverage of current control interventions across the border.

Background: Pharmacovigilance programmes monitor and help ensuring the safe use of medicines which is critical to the success of public health programmes. The commonest method used for discovering previously unknown safety risks is spontaneous notifications. In this study we examine the use of data mining algorithms to identify signals from adverse events reported in a phase IIIb/IV clinical trial evaluating the efficacy and safety of several Artemisinin-based combination therapies (ACTs) for treatment of uncomplicated malaria in African children., Methods: We used paediatric safety data from a multi-site, multi-country clinical study conducted in seven African countries (Burkina Faso, Gabon, Nigeria, Rwanda, Uganda, Zambia, and Mozambique). Each site compared three out of four ACTs, namely amodiaquine-artesunate (ASAQ), dihydroartemisinin-piperaquine (DHAPQ), artemether-lumefantrine (AL) or chlorproguanil/dapsone and artesunate (CD+A). We examine two pharmacovigilance signal detection methods, namely proportional reporting ratio and Bayesian Confidence Propagation Neural Network on the clinical safety dataset., Results: Among the 4,116 children (6-59 months old) enrolled and followed up for 28 days post treatment, a total of 6,238 adverse events were reported resulting into 346 drug-event combinations. Nine signals were generated both by proportional reporting ratio and Bayesian Confidence Propagation Neural Network. A review of the manufacturer package leaflets, an online Multi-Drug Symptom/Interaction Checker (DoubleCheckMD) and further by therapeutic area experts reduced the number of signals to five. The ranking of some drug-adverse reaction pairs on the basis of their signal index differed between the two methods., Conclusions: Our two data mining methods were equally able to generate suspected signals using the pooled safety data from a phase IIIb/IV clinical trial. This analysis demonstrated the possibility of utilising clinical studies safety data for key pharmacovigilance activities like signal detection and evaluation. This approach can be applied to complement the spontaneous reporting systems which are limited by under reporting.

Background: Malaria in Zambia remains a public health and developmental challenge, affecting mostly children under five and pregnant women. In 2002, the first-line treatment for uncomplicated malaria was changed to artemether-lumefantrine (AL) that has proved to be highly efficacious against multidrug resistant Plasmodium falciparum., Objective: The study objective was to determine whether dihydroartemisinin-piperaquine (DHA/PQP) had similar efficacy, safety and tolerability as AL for the treatment of children with uncomplicated P. falciparum malaria in Ndola, Zambia., Methods: Between 2005 and 2006, 304 children (6-59 months old) with uncomplicated P. falciparum were enrolled, randomized to AL (101) or DHA/PQP (203) and followed up for 42 days. Outcome of treatment was defined according to the standard WHO classification, i.e. early treatment failure (ETF), late clinical failure (LCF, late parasitological failure (LPF) and adequate clinical and parasitological response (ACPR). Recurrent infections were genotyped to distinguish between recrudescence and new infection., Results: No ETF was observed. At day 28, PCR-uncorrected ACPR was 92% in the DHA/PQP and 74% in the AL arm (OR: 4.05; 95%CI: 1.89-8.74; p < 0.001). Most failure were new infections and PCR-corrected ACPR was similar in the two study arms (OR: 0.69; 95%CI: 0.22-2.26; p = 0.33). Similar results were observed for day 42, i.e. higher PCR-uncorrected ACPR for DHA/PQP, mainly due to the difference observed up to day 28, while the PCR-corrected ACPR was similar: DHA/PQP: 93% (179/192), AL: 93% (84/90), (OR: 0.92; 95%CI: 0.30-2.64; p = 0.85). Except for cough, more frequent in the DHA/PQP arm (p = 0.04), there were no differences between treatment arms in the occurrence of adverse events. Two serious adverse events were probably associated to AL treatment., Conclusion: DHA/PQP was as efficacious, safe and well tolerated in treatment of uncomplicated malaria as AL, though in the latter group more new infections during the follow up were observed. DHA/PQP seems a potential candidate to be used as an alternative first-line or rescue treatment in Zambia., Trial Registration: ISRCTN16263443, at http://www.controlled-trials.com/isrctn.

Background: Artemisinin combination therapies (ACTs) are currently the preferred option for treating uncomplicated malaria. Dihydroartemisinin-piperaquine (DHA-PQP) is a promising fixed-dose ACT with limited information on its safety and efficacy in African children., Methodology/principal Findings: The non-inferiority of DHA-PQP versus artemether-lumefantrine (AL) in children 6-59 months old with uncomplicated P. falciparum malaria was tested in five African countries (Burkina Faso, Kenya, Mozambique, Uganda and Zambia). Patients were randomised (2:1) to receive either DHA-PQP or AL. Non-inferiority was assessed using a margin of -5% for the lower limit of the one-sided 97.5% confidence interval on the treatment difference (DHA-PQP vs. AL) of the day 28 polymerase chain reaction (PCR) corrected cure rate. Efficacy analysis was performed in several populations, and two of them are presented here: intention-to-treat (ITT) and enlarged per-protocol (ePP). 1553 children were randomised, 1039 receiving DHA-PQP and 514 AL. The PCR-corrected day 28 cure rate was 90.4% (ITT) and 94.7% (ePP) in the DHA-PQP group, and 90.0% (ITT) and 95.3% (ePP) in the AL group. The lower limits of the one-sided 97.5% CI of the difference between the two treatments were -2.80% and -2.96%, in the ITT and ePP populations, respectively. In the ITT population, the Kaplan-Meier estimate of the proportion of new infections up to Day 42 was 13.55% (95% CI: 11.35%-15.76%) for DHA-PQP vs 24.00% (95% CI: 20.11%-27.88%) for AL (p<0.0001)., Conclusions/significance: DHA-PQP is as efficacious as AL in treating uncomplicated malaria in African children from different endemicity settings, and shows a comparable safety profile. The occurrence of new infections within the 42-day follow up was significantly lower in the DHA-PQP group, indicating a longer post-treatment prophylactic effect., Trial Registration: Controlled-trials.com ISRCTN16263443.