A Study to Learn About the Treatment LTP001 in Healthy Participants (Part A) and in Participants With PAH (Part B)

Prior treatment

• Part A: Use of any investigational drugs within 5 half-lives or within 30 days or until the expected pharmacodynamic effect has returned to baseline prior to initial dosing, whichever is longer. Part B: Women of child-bearing potential unless they are using highly effective methods of contraception

Other illness

• Part A: History or current diagnosis of clinically significant ECG or cardiac abnormalities indicating significant risk of safety for participants. Part B: Any surgical or medical condition which may place the participant at higher risk from his/her participation in the study
• Part A: History of hypersensitivity to the investigational compound/compound class or excipients being used in this study. Part B: Sexually active males unwilling to use a condom during intercourse while taking study treatment and for 24 hours after stopping study treatment.
• Part B: History of hypersensitivity to any of the study treatments or excipients

• Part A: Signed informed consent must be obtained prior to participation in the study. Part B: Confirmed diagnosis of pulmonary arterial hypertension
• Part A: Healthy male and non-childbearing potential female participants Part B: Pre-randomization PVR ≥400 dyn.sec.cm
• Part A: In good health in the opinion of the investigator and as determined by medical history, physical examination, vital signs, ECG, and laboratory tests. Part B: Treatment with stable doses of standard-of-care PAH therapies
• Part A: Able to read, speak, and understand the local language, to understand and comply with the requirements of the study. Part B: 6MWD ≥ 150 m and ≤550 m