Study to Assess the Blood Concentrations and Actions of Recombinant Human Parathyroid Hormone (rhPTH [1-84]) When Given Once and Twice Daily to Participants With Hypoparathyroidism

Inclusion Criteria

• An understanding, ability, and willingness to fully comply with study procedures and restrictions.
• Ability to voluntarily provide written, signed, and dated informed consent as applicable to participate in the study.
• Adult men or women aged greater than or equal (>=) 18 years at the time of consent. The date of participant signature of the informed consent is defined as the beginning of the Screening Period. The Screening Period for this study may encompass both the Administrative Screening Period (if needed) and the Clinical Screening Period. For purposes of this inclusion criterion, age will only be assessed at the time the informed consent is first signed by the study participant.
• History of hypoparathyroidism for >=12 months, post-diagnosis, inclusive of historical biochemical evidence of hypocalcemia with concomitant serum intact parathyroid hormone (PTH) concentrations below the lower limit of the laboratory normal range.
• Requirement for supplemental oral calcium treatment >=1000 milligrams (mg) elemental calcium per day.
• Requirement for therapy with active forms of vitamin D at a minimum dose of >=0.25 microgram (mcg) per day (that is, >=0.25 mcg calcitriol or equivalent per day).
• Serum calcium level within the laboratory normal reference range based on clinical chemistry lab results at the Clinical Screening Visit (based on central and/or local lab results) and Treatment Period 1, Day -2 (based on central and/or local lab results), or if outside of normal range, considered not clinically significant by the investigator.
• Urinary calcium excretion >=200mg (5 millimolar [mmol])/24 hour (h), based on a 24-hour collection, collected anytime during the Clinical Screening Period, but prior to check-in to the Clinical Research Center (CRC) at Treatment Period 1, Day -2 (based on central and/or local lab results).
• Serum magnesium level within the laboratory normal range at the Clinical Screening Visit or, if outside of normal range, considered not clinically significant by the investigator.
• Serum thyroid function tests within normal laboratory limits at the Clinical Screening Visit, or, if outside of normal range, considered as not clinically significant by the investigator.
• Serum 25-hydroxyvitamin D (25(OH)D) level between the lower limit of normal and 1.5-fold the laboratory upper limit of normal, or, if outside of this range, considered not clinically significant by the investigator, at the Clinical Screening Visit.
• Serum creatinine less than ( ) 60 millilitre (mL)/minute (>1.002mL/ Second [s]) at the Clinical Screening Visit, and serum creatinine =3 months) hormone replacement therapy is acceptable; 6 months - fluoride tablets, oral bisphosphonates, methotrexate, growth hormone, digoxin, raloxifene or similar selective estrogen receptor modulators (SERMs); 12 months - intravenous bisphosphonates, drug or alcohol abuse, as determined by the investigator.
• Presence of any clinically significant results from laboratory tests, vital signs assessments, or electrocardiograms (ECGs), as judged by the investigator.
• Twelve-lead ECG values (average of triplicate readings) demonstrating QTc>450 millisecond (msec) (males) or >470 msec (females) at the Clinical Screening Visit and/or any time points up to and including predose of Day 1 (Period 1).
• Any medical condition or prior therapy that, in the opinion of the investigator, would make the participant unsuitable for this study.
• Positive test result for any of the following viral infections at the Clinical Screening Visit: Hepatitis B surface antigen; hepatitis C; human immunodeficiency virus (HIV) 14. Known significant bleeding diathesis that could preclude multiple venipunctures as determined by the investigator.
• Participants who have donated a total of 100 mL to 499 mL of whole blood within 30 days prior to dosing, or participants who have donated a total of more than 499 mL of whole blood within 56