Vergleich der Adjuvanzien AS01 und AS02 im Rahmen einer doppelt blinden, randomisierten Studie des Malariavakzinekandidaten RTS,S bei Kindern in Gabun: Klinische Sicherheit und Verlauf der Laborwerte über einen Zeitraum von 14 Monaten

Diese Phase II Doppelblind-Studie erfolgte, um die Sicherheit und Verträglichkeit des Malariaimpfstoffkandidaten RTS,S mit den zwei unterschiedlichen Adjuvanzien AS01 und AS02 zu vergleichen. Dafür wurden 180 Kinder zwischen 18 Monaten und 4 Jahren in die Studie eingeschlossen. Sie erhielten randomisiert RTS,S/AS01 oder RTS,S/AS02. Jedes Kind erhielt 3 Impfdosen im Abstand von jeweils einem Monat. Alle Kinder wurden direkt nach der Impfung für eine Stunde überwacht. Nach jeder Impfung schloss sich eine 6 tägige tägliche Verlaufskontrolle an. Bis zum Ende der Studie wurden die Kinder einmal monatlich aufgesucht. Es erfolgte eine aktive und passive Ermittlung von unerwünschten Ereignissen. Zu vier festgelegten Zeitpunkten wurden Blutbild, Leber- und Nierenfunktionswerte und Bilirubin überprüft. Beide Impfstoffe wurden gut vertragen und zeigten ein gutes Sicherheitsprofil. Die lokalen erwarteten Symptome Schmerz und Schwellung traten im Verlauf mit zunehmender Impfdosis häufiger auf. Alle unerwünschten einfachen und schweren Ereignisse standen nicht im Zusammenhang mit den Impfstoffen. Impfstoffbedingte Veränderungen der Laborwerte sahen wir nicht. Die Ergebnisse dieser Studie sollten die Entscheidung unterstützen, RTS,S/AS01 für die Phase III zu verwenden

A Randomized Trial Assessing the Safety and Immunogenicity of AS01 and AS02 Adjuvanted RTS,S Malaria Vaccine Candidates in Children in Gabon

Background:The malaria vaccine candidate antigen RTS,S includes parts of the pre-erythrocytic stage circumsporozoite protein fused to the Hepatitis B surface antigen. Two Adjuvant Systems are in development for this vaccine, an oil-in water emulsion – based formulation (AS02) and a formulation based on liposomes (AS01).Methods & Principal Findings:In this Phase II, double-blind study (NCT00307021), 180 healthy Gabonese children aged 18 months to 4 years were randomized to receive either RTS,S/AS01E or RTS,S/AS02D, on a 0–1–2 month vaccination schedule. The children were followed-up daily for six days after each vaccination and monthly for 14 months. Blood samples were collected at 4 time-points. Both vaccines were well tolerated. Safety parameters were distributed similarly between the two groups. Both vaccines elicited a strong specific immune response after Doses 2 and 3 with a ratio of anti-CS GMT titers (AS02D/AS01E) of 0.88 (95% CI: 0.68–1.15) post-Dose 3. After Doses 2 and 3 of experimental vaccines, anti-CS and anti-HBs antibody GMTs were higher in children who had been previously vaccinated with at least one dose of hepatitis B vaccine compared to those not previously vaccinated.Conclusions:RTS,S/AS01E proved similarly as well tolerated and immunogenic as RTS,S/AS02D, completing an essential step in the age de-escalation process within the RTS,S clinical development plan

Seed exchange networks for agrobiodiversity conservation. A review

The circulation of seed among farmers is central to agrobiodiversity conservation and dynamics. Agrobiodiversity, the diversity of agricultural systems from genes to varieties and crop species, from farming methods to landscape composition, is part of humanity's cultural heritage. Whereas agrobiodiversity conservation has received much attention from researchers and policy makers over the last decades, the methods available to study the role of seed exchange networks in preserving crop biodiversity have only recently begun to be considered. In this overview, we present key concepts, methods, and challenges to better understand seed exchange networks so as to improve the chances that traditional crop varieties (landraces) will be preserved and used sustainably around the world. The available literature suggests that there is insufficient knowledge about the social, cultural, and methodological dimensions of environmental change, including how seed exchange networks will cope with changes in climates, socio-economic factors, and family structures that have supported seed exchange systems to date. Methods available to study the role of seed exchange networks in the preservation and adaptation of crop specific and genetic diversity range from meta-analysis to modelling, from participatory approaches to the development of bio-indicators, from genetic to biogeographical studies, from anthropological and ethnographic research to the use of network theory. We advocate a diversity of approaches, so as to foster the creation of robust and policy-relevant knowledge. Open challenges in the study of the role of seed exchange networks in biodiversity conservation include the development of methods to (i) enhance farmers' participation to decision-making in agro-ecosystems, (ii) integrate ex situ and in situ approaches, (iii) achieve interdisciplinary research collaboration between social and natural scientists, and (iv) use network analysis as a conceptual framework to bridge boundaries among researchers, farmers and policy makers, as well as other stakeholders

Seed exchange networks for agrobiodiversity conservation. A review

The circulation of seed among farmers is central to agrobiodiversity conservation and dynamics. Agrobiodiversity, the diversity of agricultural systems from genes to varieties and crop species, from farming methods to landscape composition, is part of humanity's cultural heritage. Whereas agrobiodiversity conservation has received much attention from researchers and policy makers over the last decades, the methods available to study the role of seed exchange networks in preserving crop biodiversity have only recently begun to be considered. In this overview, we present key concepts, methods, and challenges to better understand seed exchange networks so as to improve the chances that traditional crop varieties (landraces) will be preserved and used sustainably around the world. The available literature suggests that there is insufficient knowledge about the social, cultural, and methodological dimensions of environmental change, including how seed exchange networks will cope with changes in climates, socio-economic factors, and family structures that have supported seed exchange systems to date. Methods available to study the role of seed exchange networks in the preservation and adaptation of crop specific and genetic diversity range from meta-analysis to modelling, from participatory approaches to the development of bio-indicators, from genetic to biogeographical studies, from anthropological and ethnographic research to the use of network theory. We advocate a diversity of approaches, so as to foster the creation of robust and policy-relevant knowledge. Open challenges in the study of the role of seed exchange networks in biodiversity conservation include the development of methods to (i) enhance farmers' participation to decision-making in agro-ecosystems, (ii) integrate ex situ and in situ approaches, (iii) achieve interdisciplinary research collaboration between social and natural scientists, and (iv) use network analysis as a conceptual framework to bridge boundaries among researchers, farmers and policy makers, as well as other stakeholders