Enzalutamide and Niclosamide in Treating Patients With Recurrent or Metastatic Castration-Resistant Prostate Cancer

Inclusion Criteria: * Patients must have histologically or cytologically confirmed carcinoma of the prostate (CaP); CaP can be recurrent disease after definitive therapy (radical prostatectomy or radiation therapy) for localized CaP, or metastatic CaP * Patients must have CaP deemed to be castration-resistant by one or more of the following criteria (despite androgen deprivation when applicable): * Progression of unidimensionally measurable disease assessed within 42 days prior to initial administration of drug * Progression of evaluable but not measurable disease assessed within 42 days prior to initial administration of drug for PSA evaluation and for imaging studies (e.g, bone scans) * Rising PSA, defined as at least two consecutive rises in PSA to be documented over a reference value (measure 1); the first rising PSA (measure 2) should be taken at least 7 days after the reference value; a third confirmatory PSA measure (2nd beyond the reference level) should be greater than the second measure, and it must be obtained at least 7 days after the 2nd measure; if this is not the case, a fourth PSA measurement is required to be taken and be greater than the second measure * Measurable disease is not required: * Patients who have measurable disease must have had X-rays, computed tomography (CT) scans or physical examinations used for tumor measurement completed within 28 days prior to initial administration of drug * Patients must have non-measurable disease (such a…