Study of KK3910 in Healthy Volunteers and Patients With Essential Hypertension

• Placebo (Drug): Placebo is administered single dose or multiple dose by SC injection.
• KK3910 (Drug): KK3910 is administered single dose or multiple dose by SC injection.

Primary outcomes

• Number of participants with adverse events (AEs) [Part 1 : Day 1 to Day 85, Part 2: Day 1 to Day 155, Part 3: Day 1 to Day 155]: For adverse events that occurred after administration of the investigational drug, number of subjects with AEs and occurrence frequency are evaluated.

Secondary outcomes

• Time to the maximum concentration [Part 1 : Day 1 to Day 85, Part 2 : Day 1 to Day 155, Part 3: Day 1 to Day 155]
• The maximum concentration [Part 1 : Day 1 to Day 85, Part 2 : Day 1 to Day 155, Part 3: Day 1 to Day 155]
• Area under the concentration-Time curve [Part 1 : Day 1 to Day 85, Part 2 : Day 1 to Day 155, Part 3: Day 1 to Day 155]

Sex: All, ages: 18 Years to 80 Years, accepts healthy volunteers

Inclusion Criteria: Part 1

* Voluntary consent to participate in this study must be given (in writing)
* Japanese healthy adults or non-Asian healthy men 18 to < 55 years at the time of informed consent ( Japanese healthy adults 65 to < 80 years for the elderly cohort)
* BMI is within the specified range at screening

Inclusion Criteria: Part 2

* Voluntary consent to participate in this study must be given (in writing)
* Japanese patients with essential hypertension, aged 18 to <65 years at the time of informed consent
* BMI is within the specified range at screening

Inclusion Criteria: Part 3

* Voluntary consent to participate in this study must be given (in writing)
* Japanese patients with essential hypertension, aged 18 to <80 years at the time of informed consent
* BMI is within the specified range at screening

Exclusion Criteria: Part 1

* History of any respiratory disease, heart disease, gastrointestinal disease, renal disease, liver disease, psychiatric disorder, autoimmune disease, or malignant tumor that may affect assessments in the study, as judged by principal investigator or subinvestigator.
* History of or current drug allergy
* History of or current alcoholism or drug addiction
* Smoking within the specified period
* infection within the specified period
* Any condition judged by the investigator or subinvestigator to be unsuitable for participation in the study

Exclusion Criteria: Part 2

* History of any respiratory disease, heart disease, gastrointestinal disease, renal disease, liver disease, psychiatric disorder, autoimmune disease, or malignant tumor that may affect assessments in the study, as judged by principal investigator or subinvestigator.
* History or of current drug allergy
* History of or current alcoholism or drug addiction
* Pregnant or breastfeeding patients, or patients willing to have a child during the study
* Smoking within the specified period
* infection within the specified period
* Any condition judged by the investigator or subinvestigator to be unsuitable for participation in the study

Exclusion Criteria: Part 3

* History of any respiratory disease, heart disease, gastrointestinal disease, renal disease, liver disease, psychiatric disorder, autoimmune disease, or malignant tumor that may affect assessments in the study, as judged by principal investigator or subinvestigator.
* History or of current drug allergy
* History of or current alcoholism or drug addiction
* Pregnant or breastfeeding patients, or patients willing to have a child during the study
* Smoking within the specified period
* infection within the specified period
* Any condition judged by the investigator or subinvestigator to be unsuitable for participation in the study

• Tatsuhiko Makine, Study chair, Kyowa Kirin Co., Ltd.