Research is advancing the fight against prostate cancer with two innovative bispecific antibodies: JNJ-87189401 and JNJ-78278343.

A Phase 1, first-in-human, open-label trial is evaluating the safety, tolerability, and preliminary efficacy of the combination therapy in patients with advanced prostate cancer.

These investigational therapies are designed to harness the power of the immune system by engaging specific antigens on prostate cancer cells and activating T cells to target and destroy tumors.

JNJ-87189401: Targeting PSMA

• Mechanism: JNJ-87189401 binds to prostate-specific membrane antigen (PSMA) on prostate cancer cells and CD28 on T cells. This dual binding delivers a critical costimulatory signal that enhances T-cell activation and directs immune responses toward PSMA-expressing tumors.
• PSMA is highly expressed in prostate cancer and minimally in normal tissues, making it an ideal target for this therapy.

JNJ-78278343: Targeting KLK2

• Mechanism: This bispecific antibody targets human kallikrein 2 (KLK2), a protein abundant in prostatic tissue and prostate cancer, and CD3 on T cells. By binding to these targets, JNJ-78278343 activates T cells to specifically attack KLK2-expressing cancer cells.
• KLK2 complements PSMA as a tumor-specific antigen, expanding the range of prostate cancer cells that can be targeted.

Studies indicate that combining JNJ-87189401 and JNJ-78278343 may result in enhanced T-cell activation and deeper, more durable tumor responses. The dual targeting approach provides both activation and costimulatory signals, maximizing immune system engagement. Simultaneously targeting PSMA and KLK2 seems to address a broader spectrum of prostate cancer while leveraging the immune system’s natural ability to combat cancer.

Source (PDF file).

Clinical trial.