Publications by authors named "Didier Leboulleux"

Malaria volunteer infection studies (VISs) accelerate new drug and vaccine development. In the induced blood-stage malaria (IBSM) model, volunteers are inoculated with erythrocytes infected with . Observations of elevated liver enzymes in the IBSM model with new chemical entities (NCEs) promoted an analysis of available data.

View Article and Find Full Text PDF

Background: Cambodia is the epicentre of resistance emergence for virtually all antimalarial drugs. Selection and spread of parasites resistant to artemisinin-based combination therapy (ACT) is a major threat for malaria elimination, hence the need to renew the pool of effective treatments.

Objectives: To determine whether ACT resistance haplotypes could have an effect on ferroquine in vitro antimalarial activity.

View Article and Find Full Text PDF
Article Synopsis
  • This study aimed to estimate the prevalence of Plasmodium falciparum (PfPR) as part of a Phase III trial for a malaria vaccine, conducted across 8 sites in 6 African countries from 2011 to 2013.
  • The research involved about 26,611 participants, focusing on various age groups, and utilized surveys during peak malaria transmission seasons to gather medical histories and blood samples for testing.
  • Results indicated that PfPR varied significantly by region and age, showing lower prevalence in younger children in certain areas, while overall, higher prevalence was found in the 5-19 age group, with significant correlations identified between high parasitaemia and occurrences of fever and anemia.
View Article and Find Full Text PDF

Background: Malaria remains a major global public health concern, especially in sub-Saharan Africa. The RTS,S/AS01 malaria candidate vaccine was reviewed by the European Medicines Agency and received a positive scientific opinion; WHO subsequently recommended pilot implementation in sub-Saharan African countries. Because malaria and HIV overlap geographically, HIV-infected children should be considered for RTS,S/AS01 vaccination.

View Article and Find Full Text PDF

Vaccines interrupting Plasmodium falciparum malaria transmission targeting sexual, sporogonic, or mosquito-stage antigens (SSM-VIMT) are currently under development to reduce malaria transmission. An international group of malaria experts was established to evaluate the feasibility and optimal design of a Phase III cluster randomized trial (CRT) that could support regulatory review and approval of an SSM-VIMT. The consensus design is a CRT with a sentinel population randomly selected from defined inner and buffer zones in each cluster, a cluster size sufficient to assess true vaccine efficacy in the inner zone, and inclusion of ongoing assessment of vaccine impact stratified by distance of residence from the cluster edge.

View Article and Find Full Text PDF

New interventions are needed to reduce morbidity and mortality associated with malaria, as well as to accelerate elimination and eventual eradication. Interventions that can break the cycle of parasite transmission, and prevent its reintroduction, will be of particular importance in achieving the eradication goal. In this regard, vaccines that interrupt malaria transmission (VIMT) have been highlighted as an important intervention, including transmission-blocking vaccines that prevent human-to-mosquito transmission by targeting the sexual, sporogonic, or mosquito stages of the parasite (SSM-VIMT).

View Article and Find Full Text PDF

Background: The candidate malaria vaccine RTS,S/AS01E has entered phase 3 trials, but data on long-term outcomes are limited.

Methods: For 4 years, we followed children who had been randomly assigned, at 5 to 17 months of age, to receive three doses of RTS,S/AS01E vaccine (223 children) or rabies vaccine (224 controls). The end point was clinical malaria (temperature of ≥37.

View Article and Find Full Text PDF

Background: The candidate malaria vaccine RTS,S/AS01 reduced episodes of both clinical and severe malaria in children 5 to 17 months of age by approximately 50% in an ongoing phase 3 trial. We studied infants 6 to 12 weeks of age recruited for the same trial.

Methods: We administered RTS,S/AS01 or a comparator vaccine to 6537 infants who were 6 to 12 weeks of age at the time of the first vaccination in conjunction with Expanded Program on Immunization (EPI) vaccines in a three-dose monthly schedule.

View Article and Find Full Text PDF

Many new interventions are being created to address health problems of the developing world. However, many developing countries have fragile health systems and find it difficult to accommodate change. Consequently, it is essential that new interventions are well aligned with health systems and their users.

View Article and Find Full Text PDF

Background: An ongoing phase 3 study of the efficacy, safety, and immunogenicity of candidate malaria vaccine RTS,S/AS01 is being conducted in seven African countries.

Methods: From March 2009 through January 2011, we enrolled 15,460 children in two age categories--6 to 12 weeks of age and 5 to 17 months of age--for vaccination with either RTS,S/AS01 or a non-malaria comparator vaccine. The primary end point of the analysis was vaccine efficacy against clinical malaria during the 12 months after vaccination in the first 6000 children 5 to 17 months of age at enrollment who received all three doses of vaccine according to protocol.

View Article and Find Full Text PDF

This trial was conducted to assess the immunogenicity and safety of the varicella vaccine, Okavax, when administered concomitantly with the measles, mumps and rubella vaccine, MMR-II, to children aged 12-24 months. A total of 299 children were randomized into three groups, those receiving Okavax only, MMR-II only, or both vaccines concomitantly. Antibody titers were determined by ELISA in blood samples taken immediately before, and 6 weeks after, vaccination.

View Article and Find Full Text PDF

The immunogenicity and safety of Okavax trade mark varicella vaccine, when administered concomitantly with Trimovax trade mark measles, mumps, and rubella (MMR) vaccine, were assessed in 300 Filipino children 12-24 months old. Three groups received Okavax only, Trimovax only, or both vaccines concomitantly. In sera obtained six weeks after vaccination, high varicella antibody geometric mean titers (GMTs) (115 and 79.

View Article and Find Full Text PDF

Objective: To estimate frequency of acute bacterial meningitis (ABM) in early childhood in hospital admissions, to describe clinical and diagnostic features, and to analyze mortality, complications and long term sequelae.

Design: Prospective study.

Setting: Pediatric wards and Rehabilitation Center of KEM Hospital, Pune.

View Article and Find Full Text PDF

Objectives: It is commonly held that Haemophilus influenzae pneumonia among children in Asia is mostly caused by serotypes other than b (Hib). If so, Hib conjugate vaccines would play little role in the prevention of pneumonia. In two prospective series of children hospitalized for pneumonia in China, the causative agents were searched for with a wide panel of microbiologic assays.

View Article and Find Full Text PDF