RC48 Monotherapy or Combination With Envafolimab for CDK12 Alterations mCRPC With Standard Treatment Failure

This study plans to enroll 72 mCRPC patients who have failed at least one NHT standard treatment and have exhausted PARPi treatment (such as AVPC/NEPC, requiring platinum chemotherapy resistance or intolerance). The patient carries CDK12 mutation combined with ERBB amplification (NGS or FISH) or HER2 IHC (1+, 2+, 3+). The enrolled patients were divided into queue A and queue B based on whether they carried potential immunotherapy adverse factors (including chromosome instability mutation profiles such as 11q13 co amplification, MDM2/4 amplification, FGFRs amplification, etc.). During the treatment phase of patients in queue A (excluding CDK12mut from mutation spectrum features in queue B), subjects received intravenous infusion of vediximab (2.0 mg/kg) every 2 weeks, in combination with subcutaneous injection of bevacizumab (400 mg) every 3 weeks, until disease progression or death occurred. During the treatment phase, subjects in queue B (CDK12mut combined with 11q13 co amplification, MDM2/4 amplification, FGFRs amplification and other chromosomal unstable mutation profiles) received intravenous infusion of vediximab (2.0 mg/kg) every 2 weeks until disease progression or death occurred. The main endpoint of the study was hierarchical testing, Step 1: ORR in CDK12 mut mCRPC with ERBB2 IHC 3+or FISH+or ERBB amplification (CN ≥ 4); Step2: ORR in ITT。 The secondary endpoints of the study include PSA50, PFS, OS, and safety.