Clinical Trial for Malaria Vaccines to Test for Safety, Immune Response and Protection Against Malaria

Inclusion Criteria: * Healthy adults 18 to 50 years of age (inclusive) * Women who are not pregnant by a current negative pregnancy test or of non-childbearing potential * Willing to use an FDA approved birth control method including condoms, birth control pills, sterility surgery, or intrauterine devices among others, from time of enrollment until 6 months after the end of the active phase of the study * Able to provide free and willing written informed consent to participate * Score at least 80% correct on a 10 question Assessment of Understanding * No plans to travel to a malaria endemic area during the course of the study * Free of significant health problems as established by medical history and clinical examination completed prior to the study * Available to participate and reachable for duration of study (up to five years) * Only subjects with no or low cardiac risk factors according to the Gaziano study \[53\] and a normal EKG will be included in the study Exclusion Criteria: * Pregnant (positive HCG) or nursing at screening or plans to become pregnant or nurse from the time of enrollment until 6 months after sporozoite challenge * Any past history of malaria * History of receipt of malaria vaccine * Plans to travel to malarious areas during the study period * Use of any investigational or non-registered drug or vaccine within 30 days prior to enrollment * Seropositive for HIV, hepatitis C virus (antibodies to HIV and HCV), and/or HBsAg * Subjects in the immunized group who engage in high-risk behaviors for acquiring HIV * Allergy to antimalarials or significant (e.g. systemic) hypersensitivity reactions to mosquito bites (local hypersensitivity reactions at the site of a mosquito bite are not an exclusion criterion) * History of psoriasis (given its interaction with chloroquine) * Use or planned use of any drugs with significant anti-malarial activity, such as doxycycline, clindamycin, azithromycin, or trimethoprim/sulfamethoxazole among others during the study period (subjects can withhold the use of these medications during the study period if approved by their primary care physicians, at the minimum starting from four weeks before vaccine administration until four weeks after becoming parasitemic) Any confirmed or suspected immunosuppressive or immunodeficient condition, including HIV infection and history of splenectomy * Administration of chronic (defined as more than 14 days) immunosuppressants or other immune-modifying drugs within six months of challenge * A family history of congenital or hereditary immunodeficiency * Chronic or active neurologic disease including seizure disorder * Acute or chronic, clinically significant pulmonary, cardiovascular, hepatic, or renal functional abnormality, as determined by medical history, physical examination, or abnormal baseline laboratory screening tests. * Abnormal baseline EKG obtained at screening * Acute disease at the time of enrollment * Hepatomegaly, right upper quadrant abdominal pain or tenderness: noted by physical exam during the screening process. * Administration of immunoglobulins and/or any blood products within the three months preceding immunization during the study period * Use of kanamycin or related antibiotics * Suspected or known current alcohol abuse/drug abuse as obtained by history and physical examination * Inability to make follow-up visits * Any other significant finding that in the opinion of the investigator would increase the risk of having an adverse outcome from participating in this study.