Joseph Francica (NIAID)
Lawrence Wang (NIAID)
Rachel Vistein (NIAID)
Malaria is a major disease caused by a parasite transmitted through the bite of infected female mosquitoes. Globally, an estimated 214 million cases of malaria and 438,000 deaths from malaria occur annually, with chidren in African and South Asian regions being most vulnerable. Approximately 1,500-2,000 cases of malaria are reported in the United States each year, mostly in returning travelers from malaria- endemic countries. Among the international travelers, military personnel, diplomats, pregnant women, children and older individuals with weakened immune systems are more likely to be at risk of malaria infection and mortality.
Currently, there is no licensed vaccine against Plasmodium falciparum, the deadliest species of malaria parasites. Antibodies can prevent malaria infection by binding to sporozoites, the infectious form of P. falciparum that is transmitted to humans by the bites of infected mosquitoes. The major target of anti-sporozoite antibodies is the P. falciparum circumsporozoite protein (PfCSP), an abundant surface protein on sporozoites that is essential for infecting liver cells, which is the critical step for initiating a productive infection. PfCSP is comprised of an N-terminal domain, a central region and the C-terminal region.
Researchers at the Vaccine Research Center (VRC) of the National Institute of Allergy and Infectious Diseases (NIAID) have isolated a new neutralizing recombinant human monoclonal antibody, L9, from a protected volunteer immunized with whole Plasmodium falciparum sporozoites. L9 is notable for targeting PfCSP, the immunodominant immunogen that coats the surface of the sporozoite, specifically the Plasmodium infectious form injected into the human host by the mosquito. Also, in vivo studies in a mouse model of malaria infection demonstrated that L9 is more potent than CIS43, another antimalarial mAb, at preventing malaria infection.
This technology is available for licensing for commercial development in accordance with 35 U.S.C. § 209 and 37 CFR Part 404.
<li>A passive vaccine candidate to prevent and eradicate malaria.</li>
<li>L9 may represent a more attractive passive vaccine candidate to advance through clinical testing and could yield a product superior to other vaccine candidates due to potency and preferential binding to unique epitopes on PfCSP.</li>
<li>L9 may result in more durable protection than other vaccine candidates.</li>