Trial Of Paricalcitol and Cholecalciferol(Vitamin D3) in the Treatment Of Secondary Hyperparathyroidism in Patients After ROUX-EN-Y Gastric Bypass Surgery

Inclusion Criteria:

- 1. Subject has voluntarily signed and dated an informed consent form, approved by an
Institutional Review Board (IRB), after the nature of the study has been explained
and the subject has had the opportunity to ask questions. The informed consent must
be signed before any study-specific procedures are performed.

2. Must be post bariatric (> 6 weeks and ≤ 5 years) Rou-en-Y gastric bypass surgical
patient.

3. Male or female subjects > 18 years. 4. For entry into the Treatment Period the
subject must satisfy the following criteria based on the existing laboratory values
previously drawn on clinical grounds:

- Serum calcium level 8.0-10.5 mg/dL

- Phosphorous level < 5.2 mg/dL (1.68 mmol/L)

- Serum albumin > 3.0 g/dL (30 g/L). 5. For entry into the Treatment Period the
subject must satisfy the following criteria based on screening laboratories
(Beaumont Reference Laboratories, screening laboratory values are not blinded):

- iPTH > 69 pg/ml

- Negative serum pregnancy test for female subjects of childbearing potential. 6.
In the opinion of the investigator, the subject must be receiving optimal
medical management of other co morbidities including but not limited to HTN, DM,
CVD, liver disease, and lung disease.

7. If female, subject is not breast feeding or is not pregnant (verified by
negative pregnancy test prior to the Treatment Period); or is not of
childbearing potential, defined as postmenopausal for at least one year or
surgically sterile (bilateral tubal ligation, bilateral oophorectomy or
hysterectomy); or is of childbearing potential and practicing one of the
following methods of birth control:

- Double-barrier method (any two of the following: condoms, contraceptive sponge,
diaphragm, vaginal ring with spermicidal jellies or creams, or intrauterine
device [IUD])

- Hormonal contraceptives (oral, parenteral, or transdermal) for at least three
months prior to and during study drug administration

- Maintains a monogamous relationship with a vasectomized partner

- Total abstinence from sexual intercourse during the study (minimum one complete
menstrual cycle prior to study start)

Exclusion Criteria:

- . Subject has previously been on active vitamin D therapy (calcitriol, paricalcitol,
doxercalciferol, alfacalcidol) within the 30-day washout period prior to the
Treatment Period at doses greater than 1200 IU of vitamin D3 or equivalent.

2. Subject has a history of an allergic reaction or significant sensitivity to
paricalcitol or to drugs similar to the study drug (i.e., vitamin D or vitamin D
related compounds).

3. Pregnant (confirmed by screening pregnancy test) or lactating females. 4. Subject
is expected to initiate renal replacement therapy within one year. 5. Known history
of hypercalcemia (>10.5 mg/dl), hyperphosphatemia (>6 mg/dl) primary
hyperparathyroidism, or history of end-stage renal disease requiring renal
replacement therapy.

6. Full remission from a malignancy for less than one year (except completely excised
non-Melanoma skin cancer e.g., basal or squamous carcinoma) or any history of bone
metastasis.

7. Subject has co-morbid conditions (e.g., advanced malignancy, advanced liver
disease) with a life expectancy less than 1 year.

8. Subject has received any investigational drug within 30 days prior to study drug
administration or is currently enrolled in another clinical trial.

9. Subject has a history of active kidney stones within the 2 years prior to the
Screening Period.

10. Subject has poorly controlled hypertension (systolic blood pressure > 180 mmHg
and/or diastolic blood pressure > 110 mmHg at the Screening Visit (confirmed by
repeat).

11. Subject has history of renal artery stenosis, primary aldosteronism or
pheochromocytoma, 12. Subject is taking calcitonin, bisphosphonates, cinacalcet,
glucocorticoids (except topical or inhaled glucocorticoids), or other drugs that may
affect calcium or bone metabolism, other than aluminum, calcium and non-calcium
containing phosphate binders or female subjects on stable (same dose and product for
three months) estrogen and/or progestin therapy.

13. Subject is currently receiving immunosuppressant therapy and/or high doses
(non-maintenance therapy) of glucocorticoids (> 5 mg/day of prednisone or
equivalent).

14. Subject has had acute renal failure within 12 weeks of the Screening Phase
defined by an acute rise in serum Cr (of at least 0.5 mg/dL or 44 micromoles/L) to
more than 4 g/dL (350 micromoles/L).

15. Subject is known to be HIV positive. 16. Use of known inhibitors (i.e.,
ketoconazole) or inducers (i.e., carbamazepine) of cytochrome P450 3 A (CYP3 A)
within two weeks prior to study drug administration.

17. For any reason, subject is considered by the Investigator to be an unsuitable
candidate to receive paricalcitol capsules or is put at risk by study procedures.

18. Subject has a history of drug or alcohol abuse within six months prior to
screening.

19. Subject has had a liver or kidney transplant. 20. Stage V CKD subjects on renal
replacement therapy are explicitly excluded. 21. Subject has had a CVA within the
last 3 months.