Study Evaluating the Biologic Activity of Guanabenz in Bone Metastasis

Inclusion Criteria:

1. ≥ 18 years old at the time of informed consent
2. Ability to provide written informed consent and HIPAA authorization
3. Solid organ malignancy with documented bone metastasis by imaging
4. Adequate liver function (serum total bilirubin \<= 3 and AST/ALT \<= 3 times the upper normal limit)
5. Adequate renal function (serum creatinine \<= 2mg/dL)
6. Ability to swallow oral tablets
7. Females of childbearing potential must have a negative pregnancy test \<= 28 days prior to registration. All females of childbearing potential who are sexually active, must agree to use a highly reliable method of contraception to prevent pregnancy. These include abstinence, partner with previous vasectomy, placement of an intrauterine device (IUD), condom with spermicidal foam/gel/film/cream/suppository, diaphragm or cervical vault cap, or hormonal birth control (pills or injections).

   NOTE: Females are considered of childbearing potential unless they are surgically sterile (they have undergone a hysterectomy, bilateral tubal ligation, or bilateral oophorectomy) or they are postmenopausal (\> 12 months since last menses).
8. Patients are permitted to participate in other clinical trials while participating in this trial.
9. Patients will receive standard of care systemic treatment for underlying solid malignancy as deemed necessary by treating physician.

Exclusion Criteria:

1. No prior history of bisphosphonate ordenosumab use in the past 12 months
2. No history of SRE within past 3 months

   1. Excruciating bone pain requiring RT
   2. Cord compression
   3. Hypercalcemia \[serum calcium \>10.5\]
   4. Pathologic fracture
3. No history of Paget's disease
4. No history of epilepsy/seizures
5. No history of hypotension (defined as resting systolic blood pressure of \< 110 mm Hg or diastolic blood pressure of \< 70 mm Hg) or orthostasis (defined as drop in systolic blood pressure of \>20 mm Hg or increase in HR of \> 20 from supine to standing position).