The objective of this study is to investigate the pharmacokinetics, safety, and tolerability of AK159 administered to healthy postmenopausal women.

This study consists of two parts: Part 1 and Part 2. The Part 1 is a single-center, randomized, 2-way crossover study that investigates the pharmacokinetics, safety, and tolerability of teriparatide after a single dose of AK159 (5 levels) and estimates the relative bioavailability of AK159 with subcutaneous teriparatide acetate in healthy post-menopausal women.

The Part 2 is a multiple-center, randomized, double-blind, positive- and placebo-controlled, parallel study that compares the pharmacokinetics, bone makers, safety, and tolerability of teriparatide after a weekly doses of AK159 (4 levels) for 6 weeks with placebo and a weekly doses of subcutaneous teriparatide acetate in healthy post-menopausal women.

Inclusion Criteria:

• Healthy postmenopausal ethnic Japanese women
• At least 45 years of age at the time consent is obtained
• Give voluntary consent in writing with a sufficient understanding of the study.

Exclusion Criteria:

• Clinical abnormality identified in the laboratory tests
• Weight < 40.0 kg
• Body mass index < 17.5 or >=30.5
• History of disease of the kidneys, liver, heart, brain, or other organ that makes them ineligible as subjects
• Previously received radiation treatment potentially affecting bone
• Clinical abnormality identified in the 12-lead ECGs performed at the study center during the screening period
• Systolic blood pressure < 90 mmHg
• Serum calcium level exceeding 10.4 mg/dL
• History of contact dermatitis or skin disease potentially compromising study evaluation
• Used drugs which impact bone metabolism in the 8-week period preceding investigational product administration
• Used a bisphosphonate
• Used a teriparatide product