A Study to Assess the Efficacy and Safety of Lorundrostat in Participants With Obstructive Sleep Apnea and Hypertension

Prior treatment

• Any surgery for sleep apnea or major ear, nose or throat surgery, including tonsillectomy and adenoidectomy within 3 months prior to Screening, or planned during participation in the study or within 1 month of the last study visit.
• Use of bilevel positive airway pressure (BiPAP) therapy.
• Participants who regularly use caffeine stimulants or participants who are unwilling to reduce intake to 300 mg per day (approximately 3 cups of coffee), for a period of at least 3 days prior to the Screening visit or a sleep study
• Unstable or currently symptomatic cardiovascular disease or hospitalization in the 6 months prior to Screening
• Previously diagnosed, recurrent orthostatic hypotension

Other illness

• Diagnosis of Obesity Hypoventilation Syndrome or daytime hypercapnia
• History of clinically relevant medical, behavioral, or psychiatric disorder, other than OSA, that is associated with insomnia or excessive sleepiness

Lab values

• Type 2 diabetes mellitus (T2DM) with a glycosylated hemoglobin (HbA1c) greater than (\>) 9 percent (%) (\>74.9 millimoles per mol \[mmol/mol\]) at the Screening Visit or history of diabetic ketoacidosis in the 6 months prior to the Screening Visit
• eGFR less than (\<) 45 milliliter per minute per 1.73 meter square (mL/min/1.73 m\^2) at Screening using serum creatinine or cystatin-C
• Treatment with MRAs and/or epithelial sodium channel (ENaC) inhibitors within 1 month of the Screening Visit

Other

• Participants on a glucagon-like peptide-1 (GLP-1) agonist.
• Have diagnosis of central or mixed sleep apnea with % of mixed or central apneas/hypopneas ≥50%, or diagnosis of Cheyne Stokes Respiration
• Diagnosed with Child-Pugh Class C
• Requirement for nocturnal use of supplemental oxygen
• Women who are pregnant, plan to become pregnant, or are breastfeeding
• Current night-shift worker or anticipated to become a night-shift worker for 3 days continuously during the duration of the study.

• Body mass index (BMI) ≥ 27 kilograms per meter square (kg/m\^2)
• Previously diagnosed with moderate-to-severe OSA
• AHI ≥15 events per hour (/hr) prior to Randomization
• AOBP SBP of ≥130 and less than or equal to (≤) 180 millimeter of mercury (mmHg) and AOBP diastolic blood pressure (DBP) ≥60 and ≤110 mmHg
• Participants on CPAP or PAP therapy are eligible provided they are on PAP for ≥4 hours per night (documented) and for at least 3 months prior to the study enrollment (documented)
• Participants not currently on PAP therapy, and not anticipated to start PAP for the duration of the study
• Fertile male and female participants of childbearing potential, and their partners, must agree to use protocol-defined methods of highly effective contraception from the Screening Visit until 28 days after the last dose of study drug