CD28 and prostate cancer: Additional ongoing trials evaluating the efficacy of BsAbs in prostate cancer treatment include a phase 1/2 study of REGN4336 (a PSMA × CD3 BsAb) administered alone or with cemiplimab in mCRPC (NCT05125016) and a phase 1 trial combining JNJ-87189401 (PSMA × CD28) with JNJ-78278343 (KLK2 × CD3) in advanced prostate cancer (NCT06095089).