Castrate Resistant Prostate Cancer Enhertu Therapy

Inclusion Criteria: * Pathologically confirmed adenocarcinoma of the prostate * Diagnosis of mCRPC * Documented progression on androgen deprivation and novel hormonal agents, with or without progression on taxane containing regimen * Ongoing ADT to maintain serum testosterone levels below 50 ng/dL * Formalin fixed paraffin embedded tumor tissue for HER2 immunohistochemistry * Life expectancy 6 months * ECOG 0 or 1 * LVEF at least 50% * Adequate Blood Clotting function * Adequate Organ and Bone Marrow function * Adequate Renal function * Adequate Hepatic function Exclusion Criteria: * History of interstitial lung disease or pneumonitis requiring steroids * Significant coronary vascular disease * Previous exposure to HER2 targeted therapy