The protocol to develop malaria transmission blocking assays and to estimate gametocyte carriage rates has been successfully accomplished in Bancoumana, Mali (NIAID Protocol 11-I-N143), and the protocol was renewed to allow another year of followup. Vaccines which block infectivity of malaria in mosquitoes have the potential to be critical tools in the drive to eliminate or eradicate malaria. Clinical development of such vaccines will require expertise in vaccinology, parasitology, and entomology, uniquely available in this collaboration. Assays to estimate the potential benefit of these vaccines need to be standardized and validated in malaria exposed populations. Baseline data is also needed to plan for a field trial of a transmission blocking vaccine, expected to be initiated in 2012. The study completed enrollment of 250 children and adults in July 2011, and the followup of this cohort was completed in June 2012. Participants were followed monthly to determine parasite carriage rates. Some gametocyte positive volunteers participated in mosquito feeding assays (both direct skin feeds and membrane feeds) to provide data on mosquito infectivity using various laboratory methods. The results of feeding experiments will be presented at the ASTMH Conference in November 2012. The Phase 1a,b clinical protocol for BSAM2/Alhydrogel+CPG 7909 was completed. This protocol combined Phase 1 studies in US and Mali adults in an innovative design. After dose escalation in the US, 30 volunteers in Mali were randomized to receive either the study vaccine or the comparator. Vaccinations were completed in Mali in August 2010 and volunteers have been followed through Study Day 720. Analyses showed the vaccine is immunogenic, with most related adverse events mild or moderate in severity. Unblinded results were presented at ASTMH in December 2011 (blinded results were presented in 2010). Epidemiologic study of malaria infection and disease in Malian infants and pregnant women is underway in Ouelessebougou, Mali. This study has thus far enrolled several hundred pregnant women as well as their newborns after delivery, and also several hundred children under 5 years of age, for longitudinal followup. Data are being collected on the frequency of clinical malaria and asymptomatic parasitemia, and samples are being collected for immunoparasitologic and host factor analyses, to determine the molecular bases for malaria pathogenesis and immunity. Initial analyses of risk factors for malaria outcomes in pregnant women and in young children have been accepted as two poster presentations at the ASTMH meeting in Nov 2012. Clinical Laboratory. The clinical lab achieved certification by the College of American Pathologists in April, 2010, and has subsequently been re-certified. This is the first clinical lab in West or North Africa to achieve CAP certification. Quality assurance processes are ongoing, and the lab continues to provide critical support for study activities for LMIV. During FY12, the clinical lab transitioned to a core facility to support other DIR activities at MRTC.

Project Start
Project End
Budget Start
Budget End
Support Year
5
Fiscal Year
2012
Total Cost
$1,486,314
Indirect Cost
City
State
Country
Zip Code
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