A Placebo-controlled Phase 1 Study to Investigate the Safety, Tolerability, and Pharmacokinetics of Single- and Multiple-ascending Doses of ACT-1014-6470 in Healthy Subjects

Inclusion Criteria: General criteria * Signed informed consent prior to any study-mandated procedure. * Healthy male subjects (both study parts) and female subjects of nonchildbearing potential (Part B) aged between 18 and 55 years (inclusive) at Screening. * Healthy on the basis of medical history, physical examination, cardiovascular assessments, and clinical laboratory tests. * Male subjects with a partner that might become pregnant must either be vasectomized or agree to practice adequate contraception from admission to the study site until 3 months after dosing, or the partner must consistently and correctly use (from Screening, during the entire study, and for at least 3 months after last study treatment intake) a highly effective method of contraception. Criteria for Part B only: • Women of non-childbearing potential must have a negative serum pregnancy test at Screening and a negative urine pregnancy test on Day-1. Exclusion Criteria: * Previous exposure to the study medication. * Any circumstances or conditions, which, in the opinion of the investigator, may affect full participation in the study or compliance with the protocol. * History or clinical evidence of any disease and/or existence of any surgical or medical condition, which, in the opinion of the investigator, are likely to interfere with the absorption, distribution, metabolism, or excretion of the study treatment. * Relevant bacterial, viral, fungal, or protozoal infection that manifested within the last 6 weeks prior to Screening and/or ongoing relevant bacterial, viral, fungal, or protozoal infection, as judged by the investigator, and/or evidence of immune dysfunction based on laboratory tests at Screening. * Any signs or symptoms of active, ongoing infection judged to be clinically relevant by the investigator (special attention should be given to clinical signs and symptoms consistent with COVID-19, e.g., fever, dry cough, dyspnea, sore throat, or fatigue).