The aim of this post-marketing observational study is to obtain further data on the long term use, safety and efficacy of Zemplar as it is prescribed in the normal clinical setting and according to the approved Summary of Product Characteristics for the treatment of secondary hyperparathyroidism in hemodialysis patients in Greece.

The primary objective of this study is to evaluate the safety of Zemplar® in the treatment of Secondary hyperparathyroidism (iParathormone>300 pg/mL) in subjects on hemodialysis treated in conditions of usual clinical care.

The primary safety endpoints of this study are to evaluate the safety of Zemplar by recording the number of hospitalizations and days hospitalized.

A secondary efficacy endpoint will be the proportion of subjects achieving therapeutic success. Therapeutic success with Zemplar® will be defined as:

• 40% reduction in the base iPTH level is achieved, and/or;
• serum iParathormone level < 300 pg/mL.

Additional secondary endpoints are the incidence (proportion of patients) of clinically meaningful hypercalcemia (defined as corrected serum calcium (Ca) > 11.0 mg/dL taken at 2 consecutive measurements), hyperphosphatemia (defined as serum phosphorous (P)>6.5 mg/dL taken at 2 consecutive measurements), and elevated Ca x P product (defined as serum Ca x P>65 mg^2/dL^2 taken at 2 consecutive measurements). Safety also will be assessed through adverse event monitoring and evaluation of laboratory variables and vital signs.

Inclusion Criteria:

• Subject is >= 18 years of age and diagnosed with secondary hyperparathyroidism and a pretreatment iParathormone > 300 pg/mL.
• Subject is receiving chronic hemodialysis.
• Subject for which treatment with Zemplar Injection is indicated clinically according to the criteria of participating investigator.
• Subject has provided their informed consent to participate.

Exclusion Criteria:

• Subject has a corrected serum calcium > 10.5 mg/dL, serum phosphorus >= 6.5 mg/dL or subjects with corrected Ca x P >= 65 mg^2/dl^2.
• Subject has known hypersensitivity and/or toxicity to vitamin D metabolites and/or other product ingredients.
• Subject has participated in clinical study within the last month.
• Zemplar is contraindicated according to the Summary of Product Characteristics.

Hemodialysis patients with secondary hyperparathyoidism treated with IV Paricalcitol according to the approved Summary of Product Characteristics