Safety and Preliminary Protective Efficacy of Genetically Attenuated GA2 Parasites.

Inclusion Criteria: * Subject is aged ≥ 18 and ≤ 35 years and in good health. * Subject has adequate understanding of the procedures of the study and agrees to abide strictly thereby. * Subject is able to communicate well with the investigator, is available to attend all study visits. * Furthermore, the subject will remain within the Netherlands from day -1 till day +28 after each parasite exposure. After CHMI, subjects have to be reachable by phone (24/7) from day -1 until day 35. * Subject agrees to inform his/her general practitioner (GP) about participation in the study. * Subject agrees to refrain from blood donation to Sanquin or for other purposes throughout the study period and for a defined period thereafter according to Sanquin guidelines. * Non-pregnant, non-lactating females of reproductive potential (i.e., have a uterus and are neither surgically sterilized nor post-menopausal) agree to use adequate contraception and to not breastfeed for the duration of study. * Subject agrees to refrain from intensive physical exercise (disproportionate to the subjects' usual daily activity or exercise routine) for twenty-one days following each immunization and during the malaria challenge period. Exclusion Criteria: * Any history, or evidence at screening, of clinically significant symptoms, physical signs or abnormal laboratory values suggestive of systemic conditions, such as cardiovascular, pulmonary, renal, hepatic, neurological, dermatological, endocrine, malignant, h…