Safety, Tolerability, and Pharmacokinetics of MK-8266 in Elderly Participants With High Blood Pressure (MK-8266-003)

Inclusion criteria

• Participants are male or non-childbearing female.
• Participant with essential hypertension (HTN), Grade 1 or 2 (as per European Society of Hypertension [ESH]) or isolated mild to moderate systolic HTN. High normal systolic BP ≥130 mmHg will be also allowed. Blood pressures to be confirmed on at least three occasions pre-study. The possibility of secondary causes of HTN should be assessed. Participants who are being treated for HTN with drugs (including beta blocking medications) may be able to participate if the drug doses can be reduced or discontinued, at the discretion of the investigator.
• Participants with a Body Mass Index (BMI) ≤35 kg/m^2 at the screening visit.
• Participants judged to be generally in good health based on medical history, physical examination, vital sign measurements (with the exception of HTN), and laboratory safety tests performed at the screening visit.
• Participant has no clinically significant abnormality (confirmed by the investigator in consultation with the Merck Clinical Monitor) on electrocardiogram (ECG) or Holter Monitor Evaluation performed at the screening visit and/or prior to administration of the initial dose of study drug.
• Participants must have a platelet count ≥150,000 cu/mL at the screening and pre-study visit.
• Participants, at screening, will have a positive Augmentation Index.
• Participant has been a nonsmoker and/or has not used nicotine or nicotine-containing products for at least 6 months; participants who have discontinued smoking or the use of nicotine/nicotine containing products for at least 3 months may be enrolled at the discretion of the investigator.
• Participant is willing to comply with the study restrictions.
• Participant has a negative test for hidden blood in the stool at screening.

Exclusion criteria

• Participants who have had situational depression may be enrolled in the study at the discretion of the investigator.
• Participant has an estimated creatinine clearance of ≤60 mL/min based on the Cockcroft-Gault equation.
• Participant has a history of stroke, chronic seizures, or major neurological disorder.
• Participant has a history of clinically significant endocrine, gastrointestinal, cardiovascular (with the exception of HTN), hematological, hepatic, immunological, renal, respiratory, or genitourinary abnormalities or diseases. Participants with a history of uncomplicated kidney stones or childhood asthma may be enrolled in the study at the discretion of the investigator.
• Patient demonstrates low blood pressure at screening and Pre-dose Day 1 while going from a semi-recumbent to standing position.
• Participant has a functional disability that can interfere with rising from a semi-recumbent position to the standing position.
• Participant has any personal or family history of a bleeding or a clotting disorder.
• Participant has a history of frequent nosebleeds.
• Participant has a history of cancer with the exceptions of: adequately treated non-melanoma skin carcinoma or carcinoma in situ of the cervix; other malignancies which have been successfully treated >10 years prior to the screening visit, for which in the judgment of both the investigator and treating physician, appropriate follow-up has revealed no evidence of recurrence from the time of treatment through the time of the screening visit; or, participants, who, in the opinion of the study investigator, are highly unlikely to sustain a recurrence for the duration of the study.
• Participant has a history of clinically significant cardiac disease including, but not limited to hemodynamically relevant heart valve disease (if there would be any uncertainty about the diagnosis, confirmation with an echocardiography within 3 months of screening is required), or evidence of secondary cardiac damage.
• Participant is categorized as a class II or greater functional classification for heart failure according to the New York Heart Association (NYHA).
• Participant is unabl