Study of Apalutamide With Carotuximab in Metastatic, Castration-Resistant Prostate Cancer

Eligibility Criteria

Inclusion Criteria:

* History of castration-resistant prostate cancer with rising PSA (prostate-specific antigen) on a contemporary ARSI (Androgen receptor (AR) signaling inhibitor: abiraterone, enzalutamide, darolutamide). Bicalutamide, nilutamide, and flutamide will not be considered as contemporary ARSIs
* Patient must have had 1 and can have up to 2 prior AR targeted therapy with the exception of apalutamide.
* Patients must decline or be ineligible for taxane therapy in the opinion of the treating physician.
* All patients must agree to use an adequate method of contraception, in the opinion of the treating investigator, while on protocol treatment and for 3 months after the last dose of protocol treatment (apalutamide and/or carotuximab)

Exclusion Criteria:

* Non-PSA producing prostate cancers such as small cell prostate cancers or those prostate cancers which exhibit radiographic progression without PSA rise
* Prior use of apalutamide
* Other prior malignancy requiring active anticancer therapy
* Prior exposure to carotuximab or any CD105 targeted antibody
* Active bleeding or pathologic medical conditions that carries a high bleeding risk
* A known diagnosis of Osler-Weber-Rendu syndrome