A Study of [225Ac]Ac-AKY-2519 in Patients With Metastatic Castration-Resistant Prostate Cancer

Inclusion Criteria:

* Age ≥ 18 years
* Histologic or cytologic confirmation of prostatic adenocarcinoma
* ECOG Performance Status of 0 or 1
* Adequate end-organ function
* Ability to give informed consent and comply with study requirements
* Patients with CNS metastases are eligible if they have received therapy and are neurologically stable, asymptomatic and not receiving corticosteroids
* Castrate levels of serum testosterone (\< 50 ng/dL)
* Documented disease progression on most recent prior line of therapy, either by PSA or imaging-based progression
* Cohort B: Received 2 or more prior doses of 177Lu-PSMA-617 (PLUVICTO)

Exclusion Criteria:

* Prior treatment with more than 2 Androgen receptor pathway inhibitors (ARPIs) and/or more than 1 taxane-based therapy in the mCRPC setting
* Prior treatment with a targeted radiotherapy

  o Exception: Cohort B is required to have had at least 2 prior doses of 177Lu-PSMA-617 (PLUVICTO)
* Prior treatment with a B7-H3 targeted therapy
* Received an investigational agent within the previous 28 days
* Impaired cardiac function or clinically significant cardiac disease
* Concurrent serious medical condition that would impair study participation or impact the assessment of treatment related toxicity