Enhanced effect of seasonal malaria chemoprevention when coupled with nutrients supplementation for preventing malaria in children under 5 years old in Burkina Faso: a randomized open label trial.

BACKGROUND: In rural African settings, most of the children under the coverage of Seasonal Malaria Chemoprevention (SMC) are also undernourished at the time of SMC delivery, justifying the need for packaging malarial and nutritional interventions. This study aimed at assessing the impact of SMC by coupling the intervention with nutrients supplementation for preventing malaria in children less than 5 years old in Burkina Faso. METHODS: A randomized trial was carried out between July 2020 and June 2021 in the health district of Nanoro, Burkina Faso. Children (n = 1059) under SMC coverage were randomly assigned to one of the three study arms SMC + Vitamin A (SMC-A, n = 353) or SMC + Vitamin A + Zinc (SMC-AZc, n = 353) or SMC + Vitamin A + PlumpyDoz(tm) (SMC-APd, n = 353)-a medium quantity-lipid-based nutrient supplement (MQ-LNS). Children were followed up for one year that included an active follow-up period of 6 months with scheduled monthly home visits followed by 6 months passive follow-up. At each visit, capillary blood sample was collected for malaria diagnosis by rapid diagnosis test (RDT). RESULTS: Adding nutritional supplements to SMC had an effect on the incidence of malaria. A reduction of 23% (adjusted IRR = 0.77 (95%CI 0.61-0.97) in the odds of having uncomplicated malaria in SMC-APd arm but not with SMC-AZc arm adjusted IRR = 0.82 (95%CI 0.65-1.04) compare to control arm was observed. A reduction of 52%, adjusted IRR = 0.48 (95%CI 0.23-0.98) in the odds of having severe malaria was observed in SMC-APd arm compared to control arm. Besides the effect on malaria, this combined strategy had an effect on all-cause morbidity. More specifically, a reduction of morbidity odds of 24%, adjusted IRR = 0.76 (95%CI 0.60-0.94) in SMC-APd arm compared to control arm was observed. Unlike clinical episodes, no effect of nutrient supplementation on cross sectional asymptomatic infections was observed. CONCLUSION: Adding nutritional supplements to SMC significantly increases the impact of this intervention for preventing children from malaria and other childhood infections. TRIAL REGISTRATION: NCT04238845.

Efficacy of a low-dose candidate malaria vaccine, R21 in adjuvant Matrix-M, with seasonal administration to children in Burkina Faso: a randomised controlled trial.

BACKGROUND: Stalled progress in controlling Plasmodium falciparum malaria highlights the need for an effective and deployable vaccine. RTS,S/AS01, the most effective malaria vaccine candidate to date, demonstrated 56% efficacy over 12 months in African children. We therefore assessed a new candidate vaccine for safety and efficacy. METHODS: In this double-blind, randomised, controlled, phase 2b trial, the low-dose circumsporozoite protein-based vaccine R21, with two different doses of adjuvant Matrix-M (MM), was given to children aged 5-17 months in Nanoro, Burkina Faso-a highly seasonal malaria transmission setting. Three vaccinations were administered at 4-week intervals before the malaria season, with a fourth dose 1 year later. All vaccines were administered intramuscularly into the thigh. Group 1 received 5 µg R21 plus 25 µg MM, group 2 received 5 µg R21 plus 50 µg MM, and group 3, the control group, received rabies vaccinations. Children were randomly assigned (1:1:1) to groups 1-3. An independent statistician generated a random allocation list, using block randomisation with variable block sizes, which was used to assign participants. Participants, their families, and the local study team were all masked to group allocation. Only the pharmacists preparing the vaccine were unmasked to group allocation. Vaccine safety, immunogenicity, and efficacy were evaluated over 1 year. The primary objective assessed protective efficacy of R21 plus MM (R21/MM) from 14 days after the third vaccination to 6 months. Primary analyses of vaccine efficacy were based on a modified intention-to-treat population, which included all participants who received three vaccinations, allowing for inclusion of participants who received the wrong vaccine at any timepoint. This trial is registered with ClinicalTrials.gov, NCT03896724. FINDINGS: From May 7 to June 13, 2019, 498 children aged 5-17 months were screened, and 48 were excluded. 450 children were enrolled and received at least one vaccination. 150 children were allocated to group 1, 150 children were allocated to group 2, and 150 children were allocated to group 3. The final vaccination of the primary series was administered on Aug 7, 2019. R21/MM had a favourable safety profile and was well tolerated. The majority of adverse events were mild, with the most common event being fever. None of the seven serious adverse events were attributed to the vaccine. At the 6-month primary efficacy analysis, 43 (29%) of 146 participants in group 1, 38 (26%) of 146 participants in group 2, and 105 (71%) of 147 participants in group 3 developed clinical malaria. Vaccine efficacy was 74% (95% CI 63-82) in group 1 and 77% (67-84) in group 2 at 6 months. At 1 year, vaccine efficacy remained high, at 77% (67-84) in group 1. Participants vaccinated with R21/MM showed high titres of malaria-specific anti-Asn-Ala-Asn-Pro (NANP) antibodies 28 days after the third vaccination, which were almost doubled with the higher adjuvant dose. Titres waned but were boosted to levels similar to peak titres after the primary series of vaccinations after a fourth dose administered 1 year later. INTERPRETATION: R21/MM appears safe and very immunogenic in African children, and shows promising high-level efficacy. FUNDING: The European & Developing Countries Clinical Trials Partnership, Wellcome Trust, and National Institute for Health Research Oxford Biomedical Research Centre.

Baseline malarial and nutritional profile of children under seasonal malaria chemoprevention coverage in the health district of Nanoro, Burkina Faso.

Seasonal Malaria chemoprevention (SMC) is one of the large-scale life-saving malaria interventions initially recommended for the Sahel subregion, including Burkina Faso and recently extended to other parts of Africa. Initially, SMC was restricted to children 3 to 59 months old, but an extension to older children in some locations was recently recommended. Further characterization of SMC population profile beyond age criterion is necessary for understanding factors that could negatively impact the effectiveness of the intervention and to define complementary measures that could enhance its impact. Children were assessed through a cross-sectional survey during the first month of the 2020 SMC campaign (July-August 2020) as part of the SMC-NUT project in the health district of Nanoro. Parameters such as body temperature, weight, height, mid-upper arm circumference (MUAC) were assessed. In addition, blood sample was collected for malaria diagnosis by rapid diagnostic tests (RDT) and microscopy, and for haemoglobin measurement. A total of 1059 children were enrolled. RDT positivity rate (RPR) was 22.2%, while microscopy positivity rate (MPR) was 10.4%, with parasitaemia levels ranging from 40 to 70480/µL. RPR and MPR increased as patient age increased. Wasting was observed in 7.25% of children under SMC coverage while the prevalence of stunting and underweight was 48.79% and 23.38%, respectively. As the age of the children increased, an improvement in their nutritional status was observed. Finally, undernourished children had higher parasite densities than children with adequate nutritional status. In the health district of Nanoro, children who received Seasonal Malaria Chemoprevention (SMC) were mostly undernourished during the period of SMC delivery, suggesting the need for combining the SMC with synergistic interventions against malnutrition to achieve best impact.

Establishment of reference values for prothrombin time, activated partial thromboplastin time and fibrinogen in adults in Burkina Faso.

The ordering of clinical haemostasis tests is increasing in Burkina Faso due to the newly emergence of cardiovascular and metabolic diseases. However, appropriate local reference values (RV) are lacking. Our study aimed to establish RV for prothrombin time (PT), activated partial thromboplastin time (aPTT) and fibrinogen assays. In 2020, we carried out a cross-sectional study at the transfusion centre of Ouagadougou and included 280 healthy blood donors (140 males and 140 females) as reference subjects (RS) according to CLSI guidelines (C28 A3). From each RS a 5 mL blood sample had been withdrawn in citrated tubes. We performed PT, aPTT and fibrinogen assays using the Sysmex™ CA660 coagulometer and Siemens™ reagents. RV were calculated using the "central 95 percentile" method. Reference values of PT, aPTT and Fibrinogen were respectively [73.84%-117.50%], [20,01-29.45] seconds and [2.04-3.83] g/L for females and [58.81%-112,31%] seconds, [20,9-29,98] seconds and [1.58-3.35] g/L for males. We report for the first time locally appropriate haemostasis RV for the Burkina Faso adult's population. They will be of clinical use to our health care professionals.

Impact and operational feasibility of adding malaria infection screening using an ultrasensitive RDT for placental and fetal outcomes in an area of high IPTP-SP coverage in Burkina Faso: the ASSER MALARIA pilot study protocol.

BACKGROUND: Malaria infection during pregnancy (MIP) is not only deleterious to the woman, but it also puts her fetus at increased risk of adverse outcomes, such as preterm delivery, low birth weight, and intrauterine growth retardation. Additionally, all-cause mortality during the first year of life in babies born to women with malaria during pregnancy is also increased. Many interventions such as IPTp-SP and long-lasting insecticidal nets have proven to be efficient at reducing malaria in pregnancy burden but adherence to recommended policies remains poor. In sub-Saharan Africa, malaria in pregnancy is often asymptomatic and many malaria infections may be missed due to the inadequate performance of the current rapid diagnostic test to detect low-level parasitemias. Therefore, additional strategies such as intermittent screening with ultrasensitive rapid diagnostic tests and treatment with an effective artemisinin-based combination therapy in addition to IPTp-SP could reduce placental malaria, peripheral malaria infection at delivery, and low birth weight. METHODS: This pilot 2-group randomized open trial with a nested qualitative social behavioral will be carried out in Nanoro district in which 340 pregnant women will be recruited. Pregnant women will be randomized into two groups and followed on a monthly basis until delivery. In the intervention group, monthly screening using ultrasensitive rapid diagnostic tests and treatment of those found to be infected with dihydroartemisinin-piperaquine will be performed. In addition, a reminder will be sent to increase the uptake of IPTp-SP doses per woman. During scheduled and unscheduled visits, malaria infection, hemoglobin level, and other clinical outcomes will be assessed and compared by the group. The primary feasibility outcome will evaluate the study site's capacity to enroll participants and the women's perception and acceptability of the intervention. The primary clinical outcome will be the prevalence of placental malaria at delivery. DISCUSSION: The present protocol aims to evaluate the feasibility on a large-scale and also to demonstrate the impact and the operational feasibility of additional screening with ultrasensitive rapid diagnostic tests and treatment with DHA-PQ on placental malaria, low birth weight, and peripheral malaria infection at delivery in a high-burden setting in Burkina Faso. TRIAL REGISTRATION: ClinicalTrials.gov , ID: NCT04147546 (14 October 2019).

Boosting the impact of seasonal malaria chemoprevention (SMC) through simultaneous screening and treatment of household members of children receiving SMC in Burkina Faso: a protocol for a randomized open label trial.

BACKGROUND: Plasmodium falciparum malaria remains a major public health concern in sub-Sahara Africa. Seasonal malaria chemoprevention (SMC) with amodiaquine + sulfadoxine-pyrimethamine is one of the most important preventive interventions. Despite its implementation, the burden of malaria is still very high in children under five years old in Burkina Faso, suggesting that the expected impact of this promising strategy might not be attained. Development of innovative strategies to improve the efficacy of these existing malaria control measures is essential. In such context, we postulate that screening and treatment of malaria in household members of children receiving SMC could greatly improve the impact of SMC intervention and reduce malaria transmission in endemic settings. METHODS: This randomized superiority trial will be carried out in the Nanoro health district, Burkina Faso. The unit of randomisation will be the household and all eligible children from a household will be allocated to the same study group. Households with 3-59 months old children will be assigned to either (i) control group (SMC alone) or (ii) intervention (SMC+ screening of household members with standard Histidin Rich Protein Rapid Diagnostic Test (HRP2-RDT) and treatment if positive). The sample size will be 526 isolated households per arm, i.e., around 1052 children under SMC coverage and an expected 1315 household members. Included children will be followed-up for 24 months to fully cover two consecutive malaria transmission seasons and two SMC cycles. Children will be actively followed-up during the malaria transmission seasons while in the dry seasons the follow-up will be passive. CONCLUSION: The study will respond to a major public health concern by providing evidence of the efficacy of an innovative strategy to boost the impact of SMC intervention.

Efficacy and immunogenicity of R21/Matrix-M vaccine against clinical malaria after 2 years' follow-up in children in Burkina Faso: a phase 1/2b randomised controlled trial.

BACKGROUND: Malaria is a leading cause of morbidity and mortality worldwide. We previously reported the efficacy of the R21/Matrix-M malaria vaccine, which reached the WHO-specified goal of 75% or greater efficacy over 12 months in the target population of African children. Here, we report the safety, immunogenicity, and efficacy results at 12 months following administration of a booster vaccination. METHODS: This double-blind phase 1/2b randomised controlled trial was done in children aged 5-17 months in Nanoro, Burkina Faso. Eligible children were enrolled and randomly assigned (1:1:1) to receive three vaccinations of either 5 µg R21/25 µg Matrix-M, 5 µg R21/50 µg Matrix-M, or a control vaccine (the Rabivax-S rabies vaccine) before the malaria season, with a booster dose 12 months later. Children were eligible for inclusion if written informed consent could be provided by a parent or guardian. Exclusion criteria included any existing clinically significant comorbidity or receipt of other investigational products. A random allocation list was generated by an independent statistician by use of block randomisation with variable block sizes. A research assistant from the University of Oxford, independent of the trial team, prepared sealed envelopes using this list, which was then provided to the study pharmacists to assign participants. All vaccines were prepared by the study pharmacists by use of the same type of syringe, and the contents were covered with an opaque label. Vaccine safety, efficacy, and a potential correlate of efficacy with immunogenicity, measured as anti-NANP antibody titres, were evaluated over 1 year following the first booster vaccination. The population in which the efficacy analyses were done comprised all participants who received the primary series of vaccinations and a booster vaccination. Participants were excluded from the efficacy analysis if they withdrew from the trial within the first 2 weeks of receiving the booster vaccine. This trial is registered with ClinicalTrials.gov (NCT03896724), and is continuing for a further 2 years to assess both the potential value of additional booster vaccine doses and longer-term safety. FINDINGS: Between June 2, and July 2, 2020, 409 children returned to receive a booster vaccine. Each child received the same vaccination for the booster as they received in the primary series of vaccinations; 132 participants received 5 µg R21 adjuvanted with 25 µg Matrix-M, 137 received 5 µg R21 adjuvanted with 50 µg Matrix-M, and 140 received the control vaccine. R21/Matrix-M had a favourable safety profile and was well tolerated. Vaccine efficacy remained high in the high adjuvant dose (50 µg) group, similar to previous findings at 1 year after the primary series of vaccinations. Following the booster vaccination, 67 (51%) of 132 children who received R21/Matrix-M with low-dose adjuvant, 54 (39%) of 137 children who received R21/Matrix-M with high-dose adjuvant, and 121 (86%) of 140 children who received the rabies vaccine developed clinical malaria by 12 months. Vaccine efficacy was 71% (95% CI 60 to 78) in the low-dose adjuvant group and 80% (72 to 85) in the high-dose adjuvant group. In the high-dose adjuvant group, vaccine efficacy against multiple episodes of malaria was 78% (95% CI 71 to 83), and 2285 (95% CI 1911 to 2568) cases of malaria were averted per 1000 child-years at risk among vaccinated children in the second year of follow-up. Among these participants, at 28 days following their last R21/Matrix-M vaccination, titres of malaria-specific anti-NANP antibodies correlated positively with protection against malaria in both the first year of follow-up (Spearman's ρ -0·32 [95% CI -0·45 to -0·19]; p=0·0001) and second year of follow-up (-0·20 [-0·34 to -0·06]; p=0·02). INTERPRETATION: A booster dose of R21/Matrix-M at 1 year following the primary three-dose regimen maintained high efficacy against first and multiple episodes of clinical malaria. Furthermore, the booster vaccine induced antibody concentrations that correlated with vaccine efficacy. The trial is ongoing to assess long-term follow-up of these participants and the value of further booster vaccinations. FUNDING: European and Developing Countries Clinical Trials Partnership 2 (EDCTP2), Wellcome Trust, and NIHR Oxford Biomedical Research Centre. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.

Assessment of a combined strategy of seasonal malaria chemoprevention and supplementation with vitamin A, zinc and Plumpy'Doz™ to prevent malaria and malnutrition in children under 5 years old in Burkina Faso: a randomized open-label trial (SMC-NUT).

BACKGROUND: Malaria and malnutrition represent major public health concerns worldwide especially in Sub-Sahara Africa. Despite implementation of seasonal malaria chemoprophylaxis (SMC), an intervention aimed at reducing malaria incidence among children aged 3-59 months, the burden of malaria and associated mortality among children below age 5 years remains high in Burkina Faso. Malnutrition, in particular micronutrient deficiency, appears to be one of the potential factors that can negatively affect the effectiveness of SMC. Treating micronutrient deficiencies is known to reduce the incidence of malaria in highly prevalent malaria zone such as rural settings. Therefore, we hypothesized that a combined strategy of SMC together with a daily oral nutrients supplement will enhance the immune response and decrease the incidence of malaria and malnutrition among children under SMC coverage. METHODS: Children (6-59 months) under SMC coverage receiving vitamin A supplementation will be randomly assigned to one of the three study arms (a) SMC + vitamin A alone, (b) SMC + vitamin A + zinc, or (c) SMC + vitamin A + Plumpy'Doz™ using 1:1:1 allocation ratio. After each SMC monthly distribution, children will be visited at home to confirm drug administration and followed-up for 1 year. Anthropometric indicators will be recorded at each visit and blood samples will be collected for microscopy slides, haemoglobin measurement, and spotted onto filter paper for further PCR analyses. The primary outcome measure is the incidence of malaria in each arm. Secondary outcome measures will include mid-upper arm circumference and weight gain from baseline measurements, coverage and compliance to SMC, occurrence of adverse events (AEs), and prevalence of molecular markers of antimalarial resistance comprising Pfcrt, Pfmdr1, Pfdhfr, and Pfdhps. DISCUSSION: This study will demonstrate an integrated strategy of malaria and malnutrition programmes in order to mutualize resources for best impact. By relying on existing strategies, the policy implementation of this joint intervention will be scalable at country and regional levels. TRIAL REGISTRATION: ClinicalTrials.gov NCT04238845 . Registered on 23 January 2020 https://clinicaltrials.gov/ct2/show/NCT04238845.

Long-term immunogenicity and immune memory response to the hepatitis B antigen in the RTS,S/AS01E malaria vaccine in African children: a randomized trial.

RTS,S/AS01E malaria vaccine contains the hepatitis B virus surface antigen and may thus serve as a potential hepatitis B vaccine. To evaluate the impact of RTS,S/AS01E when implemented in the Expanded Program of Immunization, infants 8-12 weeks old were randomized to receive either RTS,S/AS01E or a licensed hepatitis B control vaccine (HepB), both co-administered with various combinations of the following childhood vaccines: diphtheria-tetanus-acellular pertussis-Haemophilus influenzae type b, trivalent oral poliovirus, pneumococcal non-typeable Haemophilus influenzae protein D conjugate and human rotavirus vaccine. Long-term persistence of antibodies against the circumsporozoite (CS) protein and hepatitis B surface antigen (HBsAg) were assessed, together with the immune memory response to the HB antigen following a booster dose of HepB vaccine. Subgroups receiving RTS,S or the HepB control vaccine were pooled into RTS,S groups and HepB groups, respectively. One month post-HepB booster vaccination, 100% of participants in the RTS,S groups and 98.3% in the control groups had anti-HBs antibody concentrations ≥10 mIU/mL with the geometric mean concentrations (GMCs) at 46634.7 mIU/mL (95% CI: 40561.3; 53617.6) and 9258.2 mIU/mL (95% CI: 6925.3; 12377.0), respectively. Forty-eight months post-primary vaccination anti-CS antibody GMCs ranged from 2.3 EU/mL to 2.7 EU/mL in the RTS,S groups compared to 1.1 EU/mL in the control groups. Hepatitis B priming with the RTS,S/AS01E vaccine was effective and resulted in a memory response to HBsAg as shown by the robust booster response following an additional dose of HepB vaccine. RTS,S/AS01E when co-administered with PHiD-CV, HRV and other childhood vaccines, had an acceptable safety profile.

Immune response to the hepatitis B antigen in the RTS,S/AS01 malaria vaccine, and co-administration with pneumococcal conjugate and rotavirus vaccines in African children: A randomized controlled trial.

The RTS,S/AS01 malaria vaccine (Mosquirix) reduces the incidence of Plasmodium falciparum malaria and is intended for routine administration to infants in Sub-Saharan Africa. We evaluated the immunogenicity and safety of 10-valent pneumococcal non-typeable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV; Synflorix) and human rotavirus vaccine (HRV; Rotarix) when co-administered with RTS,S/AS01 ( www.clinicaltrials.gov NCT01345240) in African infants. 705 healthy infants aged 8-12 weeks were randomized to receive three doses of either RTS,S/AS01 or licensed hepatitis B (HBV; Engerix B) vaccine (control) co-administered with diphtheria-tetanus-acellular pertussis-Haemophilus influenzae type-b-conjugate vaccine (DTaP/Hib) and trivalent oral poliovirus vaccine at 8-12-16 weeks of age, because DTaP/Hib was not indicated before 8 weeks of age. The vaccination schedule can still be considered broadly applicable because it was within the age range recommended for EPI vaccination. PHiD-CV or HRV were either administered together with the study vaccines, or after a 2-week interval. Booster doses of PHiD-CV and DTaP/Hib were administered at age 18 months. Non-inferiority of anti-HBV surface antigen antibody seroprotection rates following co-administration with RTS,S/AS01 was demonstrated compared to the control group (primary objective). Pre-specified non-inferiority criteria were reached for PHiD-CV (for 9/10 vaccine serotypes), HRV, and aP antigens co-administered with RTS,S/AS01 as compared to HBV co-administration (secondary objectives). RTS,S/AS01 induced a response to circumsporozoite protein in all groups. Pain and low grade fever were reported more frequently in the PHiD-CV group co-administered with RTS,S/AS01 than PHiD-CV co-administered with HBV. No serious adverse events were considered to be vaccine-related. RTS,S/AS01 co-administered with pediatric vaccines had an acceptable safety profile. Immune responses to RTS,S/AS01 and to co-administered PHiD-CV, pertussis antigens and HRV were satisfactory.