To Evaluate Safety and Tolerability of VERU-111 in Men With Advanced Metastatic Castration Resistant Prostate Cancer

Inclusion Criteria: To be included in this study, patients should meet all of the following criteria: • Willing and able to provide written informed consent and HIPAA authorization for the release of personal health information. NOTE: HIPAA authorization may be either included in the informed consent or obtained separately. * Patients \>18 years of age. * Histological or cytologic proof of adenocarcinoma of the prostate. * Radiographic evidence of metastatic disease by CT scan or MRI and/or bone scan. * Known castration resistant prostate cancer, defined according to PCWG3 criteria. * Subjects who have metastatic castration resistant prostate cancer that have maintained ADT and have failed a novel androgen receptor agent (abiraterone or enzalutamide) defined as: * Serum PSA progression of two consecutive increases in PSA over a previous reference value within 6 months of first study treatment, each measurement at least two weeks apart. Or * Documented bone lesions by the appearance of two or more new lesions on bone scintigraphy or dimensionally-measurable soft tissue metastatic lesion assessed by CT or MRI. * Absolute PSA ≥2.0 ng/ml at screening. * Prior chemotherapy for mCRPC: * Phase 1b - ONE prior taxane chemotherapy for mCRPC will be allowed during the Phase 1b portion of study as long as the last dose was more than four weeks prior to the first dose of study drug. * Phase 2 - Prior chemotherapy for mCRPC is not allowed in the Phase 2 portion of the study. Prior chemotherapy for metastatic hormone sensitive prostate cancer will not qualify as a prior chemotherapy and the last dose must be \>6 months prior to enrollment. * Prior treatment with abiraterone, enzalutamide, bicalutamide, and/or ketoconazole is allowed. There is no limit on the maximum number or types of prior hormonal therapies received. The patients should be off prior therapy for at least two weeks (4 weeks off bicalutamide or nilutamide treatment) prior to first dose of study drug. * ECOG performance status ≤2. * Participants must have normal organ and bone marrow function measured within 28 days prior to administration of study treatment as defined below: * Hemoglobin 9.0 g/dL with no blood transfusion in the past 28 days. * Absolute neutrophil count (ANC) 1.5 x 109/L. * Platelet count 100 x 109/L. * Total bilirubin ≤1.5 x institutional upper limit of normal (ULN) (or \<2.5 x ULN for patients with known Gilberts disease). * Aspartate aminotransferase (AST) (Serum Glutamic Oxaloacetic Transaminase (SGOT))/Alanine aminotransferase (ALT) (Serum Glutamic Pyruvate Transaminase (SGPT)) ≤2.5 x institutional upper limit of normal. Note: Patients with elevations in bilirubin, AST, or ALT should be thoroughly evaluated for the etiology of this abnormality prior to entry and patients with evidence of viral infection should be excluded. * Participants must have a life expectancy \>3 months. * Male participants, and their partners, who are sexually active and of childbearing potential, must agree to the use of two highly effective forms of contraception in combination \[see Appendix E for acceptable methods\], throughout the period of taking study treatment and for at least 4 weeks after the last dose of VERU-111 to prevent pregnancy in a partner. * Other than the metastatic prostate cancer, no evidence (within 5 years) of prior malignancies (except successfully treated basal cell or squamous cell carcinoma of the skin or other cancers treated with curative intent \>3 years prior). * Participants must agree to either refrain from prolonged exposure to the sun or agree to use at least SPF 50 on all exposed skin and protective clothing during prolonged sun exposure throughout participation in this study and/or treatment with VERU-111. Exclusion Criteria: Patients that meet any of the criteria listed below will not be eligible for study entry: * Histologic identification of small cell carcinoma of the prostate or neuroendocrine pathology in either biopsy or prostatectomy tissue. * Has received external-beam radiotherapy within the last 2 weeks prior to start of study treatment. * Patients receiving full dose anticoagulation therapy are not eligible for study. * Patients with prior history of a thromboembolic event within the last 6 months. * Participation in another clinical study with an investigational product during the last 4 weeks/28 days. * Patients should be excluded if they have had prior systemic treatment with two prior taxane chemotherapies for advanced prostate cancer. No limit to other prior therapies. * Concurrent use of other anticancer agents (see Appendix G) or treatments, with the following exceptions: o Ongoing treatment with denosumab (Prolia) or bisphosphonate (e.g., zoledronic acid) is allowed. Ongoing treatment should be kept at a stable schedule; however, if medically required, a change of dose, compound, or both is allowed. * Any treatment modalities involving major surgery within 4 weeks prior to the start of study treatment. * Patients are excluded if they have active known brain metastases or leptomeningeal metastases. * Patients should be excluded if they have a positive test for hepatitis B virus surface antigen (HBV sAg) or hepatitis C virus ribonucleic acid (HCV antibody) indicating acute or chronic infection. * History of severe hypersensitivity reaction to any taxane chemotherapy. * Has imminent or established spinal cord compression based on clinical findings and/or MRI. * Any other serious illness or medical condition that would, in the opinion of the investigator, make this protocol unreasonably hazardous. * Persistent toxicities (\>Common Terminology Criteria for Adverse Event (CTCAE) grade 2) caused by previous cancer therapy, excluding alopecia. * Poor medical risk due to a serious, uncontrolled medical disorder, non-malignant systemic disease or active, uncontrolled infection. Examples include, but are not limited to, uncontrolled ventricular arrhythmia, recent (within 6 months) myocardial infarction, uncontrolled major seizure disorder, extensive interstitial bilateral lung disease, or any psychiatric disorder that prohibits obtaining informed consent. * Total bilirubin levels \> ULN or OR AST/ALT levels \>1.5xULN with WITH concomitant alkaline phosphatase levels \>2.5xULN. The following exclusion criterion is added to the Phase 1b portion of the study only: • Patients with substantial visceral disease who require immediate treatment with cytotoxic therapy