Safety and Immunogenicity of Pfs25M-EPA/AS01 and Pfs230D1M-EPA/AS01 Vaccines, Transmission Blocking Vaccines Against Plasmodium Falciparum, at Full and Fractional Dosing in Adults in Mali

The PpPfs25M and EcEPA lots, both manufactured at Walter Reed Bioproduction facility (Silver Spring, Maryland) in cGMP compliance, were used to manufacture the conjugate. PpPfs25M is a Pichia- expressed recombinant Pfs25 with a molecular mass of 18,713 Daltons.The Pfs25M- EPA was formulated as conjugated Pfs25M in 4 mM PBS to a 2X dilution of the high dose (188 (Micro)g/ml in 0.5 ml volume) in cGMP compliance at Walter Reed Bio-production facility in April 2016 and will be provided as a single use vial.

The Pfs230D1M-EPA was formulated as conjugated Pfs230D1M in 4 mM PBS to a 2X dilution of the high dose (160 (Micro)g/ml in 0.5 ml volume) in cGMP compliance at Walter Reed Bio-production facility in April 2016 and will be provided as a single use vial.

AS01B adjuvant will also be provided as a single use vial by GSK, 100 microgram/mL MPL and 100microgram/mL QS21 in a liposomal formulation in a volume of 0.625 mL. One dose injected of AS01B corresponds to 50 μg QS21 and 50 μg MPL.

ENGERIX-B (hepatitis B vaccine; recombinant): is a sterile suspension of noninfectious hepatitis B virus surface antigen (HBsAg) for intramuscular administration. It contains purified HBsAg obtained by culturing genetically engineered Saccharomyces cerevisiae cells, which carry the surface antigen gene of the hepatitis B virus. Each 1-mL adult dose contains 20 g of HBsAg adsorbed on 0.5 mg aluminum as aluminum hydroxide. FDA approved for persons 20 years of age and older for a series of 3 doses on a 0-, 1-, 6-month schedule.

Menactra is FDA approved for active immunization to prevent invasive meningococcal disease caused by Neisseria meningitidis serogroups A, C, Y, and W-135 (but does not protect against serotype B) for use in individuals 9 months through 55 years of age

Sterile isotonic (0.9%) normal saline will be commercially procured in the US and shipped to Mali at ambient temperature. Normal saline will be administered in a 0.5 mL dose as an intramuscular injection. Normal saline will also be used for diluting Pfs25M-EPA and Pfs230D1M-EPA prior to formulation with AS01B for the lower dose groups in Bamako, Mali.

Artemether/lumefantrine (Coartem(R)) is a licensed antimalarial in the US and Mali for treatment of uncomplicated malaria. It has an excellent safety profile and is widely used to treat malaria. Subjects who may have any contraindications to the use of these drugs will be excluded at screening. Coartem will be dosed with food and administered over 3 days for a total of 6 doses, as per package insert and standard adult dosing