Chemoprophylactic Activity of M5717 in PfSPZ Challenge Model

A Phase Ib, Randomized, Double-Blind, Placebo Controlled, Sequential Study of Single Oral Doses of M5717 to Explore the Chemoprophylactic Activity of M5717 in a Controlled PISPZ Challenge Model in Healthy Participants

The main purpose of this study was to assess the chemoprophylactic activity and dose-exposure-response relationship of single oral dose of M5717 administered after direct intravenous inoculation (DVI) of Plasmodium falciparum sporozoite (PfSPZ) challenge in healthy participants.

Inclusion Criteria:

• Participants who are overtly healthy as determined by medical evaluation, including no clinically significant abnormality identified on physical examination or laboratory evaluation and no active clinically significant disorder, condition, infection or disease that would pose a risk to participant safety or interfere with the study evaluation, procedures or completion
• Participants who have a body weight within 50 to 100 kilograms (kg) and body mass index within the range 19.0 to 29.9 kilograms per meter square (kg/m2) (inclusive)
• Male participants, during the study intervention period and for at least 120 days after the day of the study intervention dose (covering a full sperm cycle of 90 days starting after 5 half lives of last dose of study intervention: - refrain from donating sperm plus, either - abstain from intercourse with a woman of childbearing potential (WOCBP) or - use a male condom, when having sexual intercourse with a WOCBP, who is not currently pregnant, and advise her to use a highly effective contraceptive method with a failure rate of less than (<) 1 percent (%) per year, since a condom may break or leak
• Female participants who are: - not a WOCBP; - at least 1 year post-menopausal (amenorrhea greater than or equal to [>=] 12 months and follicle-stimulating hormone [FSH] >= 40 milli-international units per milliliter [mIU/mL]) at screening; - surgically sterile (bilateral oophorectomy, hysterectomy or bilateral salpingectomy; tubal ligation alone is not sufficient)
• Participants who are capable of giving signed informed consent, which includes compliance with the requirements (including mandatory intake of rescue medication to participants who have been administered the investigational Plasmodium falciparum sporozoite challenge) and restrictions listed in the informed consent form (ICF) and this protocol
• Other protocol defined inclusion criteria could apply

Exclusion Criteria:

• Participants with 12-Lead electrocardiogram (ECG) outside normal range (QTcF greater than [>] 450 milli seconds [ms], pulse rate [PR] > 215 ms, or QRS > 120 ms) and deemed clinically relevant by the Investigator
• Supine systolic blood pressure > 140 or < 90 millimeter of mercury (mmHg), diastolic blood pressure > 90 or < 50 mmHg, and pulse rate > 90 or < 50 beats per minute (min) at screening and at admission on Day -1 (any abnormal blood pressure or pulse rate results may be repeated once and if the repeat result is within the normal range, it is not considered to have met the exclusion criterion)
• Seropositive for human immunodeficiency virus (HIV) I and II antibody or antigen), hepatitis B virus (HBV; hepatitis B surface antigen [HBsAg]), or hepatitis C virus (HCV; antibody) tests
• Liver function tests above the upper limit of normal (ULN) (> 3 x ULN) the day before DVI / study intervention administration (Day -1)
• History or presence of diagnosed food or known drug allergies (including but not limited to allergy to any of the antimalarial rescue medications to be used in the study), or history of anaphylaxis or other severe allergic reactions
• Participant with a whole blood donation or loss of > 450 mL within 60 days before administration of study drug or unwilling to defer blood donations for 6 months
• Other protocol defined exclusion criteria could apply