ARX517 in Subjects With Metastatic Castration-resistant Prostate Cancer (ARX517)

This is an interventional treatment trial for Prostate Cancer focused on measuring ADC, Antibody drug conjugate, Prostate neoplasma, Castration-resistant, PSA increased, PSMA, Prostate specific membrane antigen, PSMA ADC, Prostate Cancer Read More

Inclusion Criteria:

1. Male subjects ≥18 years at the time of providing written informed consent
2. Pathologically confirmed adenocarcinoma of the prostate or other solid tumors
3. For prostate cancer, ongoing therapy with a gonadotropin-releasing hormone agonist or antagonist AND serum testosterone level <50 ng/dL at Screening
4. For prostate cancer, prior treatment with at least 2 Food and Drug Administration (FDA) approved treatments for metastatic castration-resistant prostate cancer.
5. Metastatic disease documented by computed tomography (CT)/ magnetic resonance imaging (MRI) and/ or bone scan; images obtained within 28 days prior to the start of study medication will be accepted as baseline

6. For prostate cancer, meet the criteria of disease progression according to the recommendations of the Prostate Cancer Working Group (PCWG) 3 by one of the following criteria:

   1. A sequential rise of PSA (second value obtained at a minimum of 1 week later) from a baseline measurement of at least 2 ng/mL (1 ng/mL is the minimum starting value if confirmed rise is only indication of progression)
   2. Radiographic progression (CT/MRI) by Response Evaluation Criteria in Solid Tumors (RECIST v 1.1) criteria
   3. Nuclear scan progression by new lesions
7. For prostate cancer, discontinuation of flutamide or nilutamide, and other non steroidal anti-androgens at least 4 weeks prior to the start of study drug; discontinuation of bicalutamide at least 6 weeks prior to start of study drug.
8. Discontinuation of radiotherapy >4 weeks prior
9. Eastern Cooperative Oncology Group performance status of 0 to 1 at Screening
10. Adequate organ function with following blood counts at Screening:
11. Adequate organ function with following Chemistry values at Screening:
12. Life expectancy of at least 6 months at Screening as per Investigator's judgment
13. Willing and able to provide written informed consent for participation in the study, and comply with all protocol requirements and assessments
14. Agrees to use contraception during the Treatment Period plus an additional 120 days after the last dose of study treatment and must refrain from donating sperm during this period.

Exclusion Criteria:

1. History of allergic reactions to any component of the ARX517.
2. Impaired pituitary or adrenal gland function (e.g., Addison's disease, Cushing's syndrome)
3. Initiation of bisphosphonate or denosumab therapy within 30 days prior to the start of study medication; subjects who are on a stable dose of these medications for at least 30 days at the time of starting study drug are eligible
4. Therapy with estrogen within 30 days prior to the start of study drug
5. Use of systemic glucocorticoids equivalent to >10 mg prednisone daily; subjects who have discontinued or are on reduced daily dose are eligible within 14 days prior to the start of study drug
6. Use of any medication such as finasteride/dutasteride known to decrease PSA levels (e.g., saw palmetto) within 30 days of start of study drug
7. Have central nervous system (CNS) metastasis, unless the CNS metastasis was treated with local therapy and has proven to be stable over the last 2 months prior to Screening, and not currently requiring ongoing systemic steroid treatment
8. History of other malignancy within the previous 2 years (no longer being actively treated), except basal cell carcinoma
9. Marked baseline prolongation of QT/QTc interval, e.g. repeated demonstrated of a QTc interval > 480 milliseconds (ms) (CTCAE grade 1) using Fridericia's QT correction formula. Major surgery within 30 days prior to the start of study drug
10. Blood transfusion within 30 days of Screening
11. Serious and /or persistent infection within 14 days of the start of study drug
12. Treatment with any investigational drug within 4 weeks prior to Day 1 of the study
13. Known seropositive test for human immunodeficiency virus or seropositive test for hepatitis C virus or hepatitis B virus (testing for hepatitis C and hepatitis B is not required)
14. Prior history of clinically significant lung disease, pneumonitis, or other clinically significant lung disease within 12 months prior to Screening, with the exception of that directly attributable to the presence of lung metastases from their underlying cancer.
15. Prior history of clinically significant ocular events, or any current ongoing active ocular infections.
16. Major surgery within 30 days prior to the start of the study drug. Poorly controlled diabetes, hypertension, history of class III or IV heart failure.