The purpose of this study is to access the safety of combining sodium selenite with
abiraterone and to see what doses of sodium selenite can be safely combined with abiraterone
in treating castration resistant prostate cancer.
· To determine the maximum tolerated dose (MTD) of sodium selenite when given in combination
- To assess the safety and tolerability of the combination of sodium selenite and
abiraterone in subjects with castration resistant prostate cancer (CRPC)
- To assess the pharmacokinetics of sodium selenite
- To assess changes in Prostate specific antigen (PSA) To evaluate the anti tumor activity
of sodium selenite and abiraterone when given in combination as determined by
biochemical progression free survival (PFS) and radiographic PFS.
- Each subject must sign an informed consent form (ICF) indicating that he understands
the purpose of and procedures required for the study and is willing to participate in
the study. Consent is to be obtained prior to the initiation of any study related
tests or procedures that are not part of standard of care for the subject's disease.
- Histologically confirmed adenocarcinoma of the prostate with metastatic disease.
- Progression on abiraterone defined by a rise in PSA at 2 time points at least 1 week
- Male ≥18 years of age.
- Prior orchiectomy or serum testosterone levels < 50 ng/dL determined within 4 weeks
prior to start of study drug
- Adequate baseline organ function as defined below:
- Hemoglobin > 9 with or without transfusion
- Platelets > 75 with or without transfusion
- Neutrophil: Absolute neutrophil > 1.0
- T bilirubin < 1.5 x Upper limit normal (ULN)
- Aspartate aminotransferase (AST)/Alanine Aminotransferase (ALT) < 2.5 x ULN
- Creatinine < 1.5 x ULN
- Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 within 2 weeks
of initiation of study drug administration.
- Ongoing androgen depletion therapy with a gonadotropin releasing hormone (GnRH) analog
or inhibitor, or orchiectomy (ie, surgical or medical castration). Note: subjects who
have not undergone orchiectomy must continue GnRH analog therapy for the duration of
- For subjects previously treated with 1st generation anti androgens (ie, flutamide,
nilutamide, or bicalutamide), discontinuation of flutamide or nilutamide therapy must
occur > 4 weeks (> 6 weeks for bicalutamide) prior to start of study drug with no
evidence of an anti androgen withdrawal response (ie, no decline in serum PSA; within
6 weeks of last dose for bicalutamide and 4 weeks of last dose for all other drugs as
- For subjects previously treated with chemotherapy, targeted therapy, immunotherapy, or
treatment with an investigational anticancer agent, discontinuation must have occurred
≥ 2 weeks, or after at least 4 half lives, whichever is longer, prior to study drug
administration. For enzalutamide and apalutamide, the washout period will be at least
3 weeks prior to start of study drug with no evidence of an anti androgen withdrawal
response (ie, no decline in serum PSA within 4 weeks of last dose.)
- For subjects previously treated with other agents approved for the treatment of
prostate cancer (5 α reductase inhibitors, estrogens, others), discontinuation of
therapy must have occurred ≥ 4 weeks prior to start of study drug. This does not apply
- Palliative radiotherapy (to bone or soft tissue lesions) must be completed > 2 weeks
prior to start of study drug.
- For subjects receiving bone-loss prevention treatment (eg, bisphosphonates or
denosumab), the subject must be on stable dose ≥ 4 weeks prior to start of study drug.
- QT interval corrected using Fridericia's method (QTcF) less than 460 msec (see
Appendix B for Fridericia's criteria).
- A man who is sexually active with a woman of childbearing potential must agree to use
an adequate method of contraception to avoid conception during the study and for 120
days after receiving the last dose of study drug. All men must also not donate sperm
during the study and for 120 days after receiving the last dose of study drug.
- Subject must be willing and able to adhere to the prohibitions and restrictions
specified in this protocol.
- Previously documented or current brain metastases.
- Untreated spinal cord compression.
- Known positive test result for human immunodeficiency virus.
- History of clinically significant cardiovascular disease including, but not limited
- Myocardial infarction or unstable angina within the 6 months prior to the first
dose of study drug.
- Clinically significant cardiac arrhythmia.
- Uncontrolled (persistent) hypertension: systolic blood pressure > 180 mHg;
diastolic blood pressure >100 mmHg.
- Congestive heart failure (New York Heart Association class III IV).
- Known active or chronic hepatitis B or hepatitis C as demonstrated by hepatitis B
surface antigen positivity and/or anti hepatitis C virus positivity, respectively.
Subjects with clinically active or chronic liver disease, including liver cirrhosis of
Child Pugh class C, are also excluded.
- History of a different malignancy except for the following circumstances: (a)
individuals with a history of other malignancies are eligible if they have been
disease free for at least 3 years and are deemed by the investigator to be at low risk
for recurrence of that malignancy, (b) individuals with a history of treatment for the
following cancers are eligible: non muscle invasive bladder cancer, basal cell, or
squamous cell carcinoma of the skin and resected melanoma in situ.
- Any serious underlying medical or psychiatric condition (eg, alcohol or drug abuse),
dementia or altered mental status or any issue that would impair the ability of the
subject to receive or tolerate the planned treatment, to understand informed consent
or that in the opinion of the investigator would contraindicate the subject's
participation in the study or that would confound the results of the study.
- Evidence of active viral, bacterial, or systemic fungal infection requiring systemic
treatment within 7 days prior to the first dose of study drug. Subjects requiring any
systemic antiviral, antifungal, or antibacterial therapy for active infection must
have completed treatment no less than 7 days prior to the first dose of study drug.
- Enrollment in another therapeutic study.
- Major surgery (eg, requiring general anesthesia) within 3 weeks before screening, or
has not fully recovered from prior surgery (ie, unhealed wound), or surgery planned
during the time the subject is expected to participate in the study. Note: subjects
with planned surgical procedures to be conducted under local anesthesia may