The purpose of this trial is to determine the safety and tolerability of ascending single and multiple oral doses of LEO 27847 in secondary hyperparathyroidism patients.

Inclusion Criteria:

• Patients aged 18 to 75 years (inclusive) at screening.
• Patients with body mass index within 18 to 34 kg/m2 (inclusive).
• Haemoglobin is stable (≥9 g/dL or 5.6 mmol/L)
• Parathyroid hormone (PTH) is ≥200 pg/mL and <800 pg/mL.
• Screening serum albumin is ≥30 g/L.
• C-reactive protein <25 mg/L.

Exclusion Criteria:

• Adjustment of vitamin D sterols within 14 days before the screening visit and patients for whom adjustment of vitamin D sterols is planned from screening until end of study.
• Adjustment of calcium supplements within 14 days before the screening visit and patients for whom adjustment of calcium supplements is planned from screening until end of study.
• Adjustment of phosphate binder within 14 days before the screening visit and patients or whom adjustment of phosphate binder is planned from screening until end of study.