 Inclusion Criteria: - Completed one of the qualifying studies i.e., patient previously took part in an Amgen study investigating the drug AMG 073 and its effects on secondary hyperparathyroidism HPT; in particular parathyroid hormone PTH, calcium and phosphorus levels in blood associated with kidney failure - Must agree to use, in the opinion of the principal investigator, highly effective contraceptive measures throughout the study Exclusion Criteria: - Pregnant or nursing females - Experienced a myocardial infarction within 3 months before day 1 - Have an unstable medical condition, defined as having been hospitalized, other than for dialysis vascular access revision, within 30 days before day 1, or otherwise unstable in the judgment of the investigator 