Prostate Cancer: PSMA-Targeted Therapy and the Precision Medicine Era
The Scale of the Problem
Prostate cancer is the most commonly diagnosed cancer in men globally and the second
leading cause of male cancer mortality, killing more than 350,000 men annually worldwide.
Most cases are initially treatable with surgery, radiation, and hormone therapy (androgen
deprivation therapy, ADT), but approximately 10–20% of patients progress to metastatic
castration-resistant prostate cancer (mCRPC) — a stage where the cancer has spread and
no longer responds to testosterone suppression. Until recently, treatment options for
mCRPC were limited and median survival was measured in months.
The identification of prostate-specific membrane antigen (PSMA) — a protein massively
overexpressed on prostate cancer cells but absent from most normal tissues — as a
therapeutic target has fundamentally changed this landscape.
What Is PSMA and Why Does It Matter?
PSMA (prostate-specific membrane antigen) is a transmembrane protein first cloned at
Memorial Sloan Kettering Cancer Center in the early 1990s. It is overexpressed on 80–90%
of prostate cancer cells, with expression increasing as the disease becomes more
aggressive. This differential expression makes it an ideal target for both imaging and therapy
— the concept known as theranostics ("we see what we treat, and we treat what we see").
PSMA-PET scanning has revolutionised prostate cancer staging. Traditional CT and bone
scans miss approximately 50% of metastatic lesions that PSMA-PET can detect — enabling
more precise treatment planning, identification of oligometastatic disease amenable to
localised treatment, and earlier detection of biochemical recurrence.
177Lu-PSMA-617 (Pluvicto): The Landmark Drug
Lutetium-177 PSMA-617 (brand name: Pluvicto) is a radioligand therapy — a molecule that
binds specifically to PSMA on cancer cells and delivers a lethal dose of beta-radiation
directly to the tumour, sparing surrounding healthy tissue. The pivotal VISION Phase 3 trial,
published in the New England Journal of Medicine in 2021, demonstrated that 177Lu-PSMA-
617 improved median overall survival from 11.3 months to 15.3 months in patients with
mCRPC who had progressed despite prior treatment — a 38% reduction in mortality risk.
The FDA initially approved 177Lu-PSMA-617 in 2022 for late-line mCRPC. In March 2025,
the FDA significantly expanded its approval for earlier-line use — specifically for PSMA-
positive mCRPC patients who could delay chemotherapy. This expanded approval
substantially increases the number of eligible patients and allows physicians to use this
targeted therapy before subjecting patients to the toxicities of conventional chemotherapy.
The LUNAR Trial: 2025's Most Exciting Prostate Data
A November 2025 Phase 2 study from UCLA Health (LUNAR trial) published in the Journal
of Clinical Oncology demonstrated that adding PNT2002 (177Lu-PSMA radioligand) before
stereotactic body radiotherapy (SBRT) more than doubled progression-free survival in men
with biochemically recurrent prostate cancer — 17.6 months versus 7.4 months for SBRT
alone. The combination also extended the time before hormone therapy was needed (24.3
months vs. 14.1 months) — a critically important quality-of-life metric for patients who wish to
avoid ADT's side effects.
Next Generation Approaches
Prostate cancer research in 2025 is highly active beyond 177Lu-PSMA-617:
▸ Alpha-emitting radioligands: 225Ac-PSMA-617 uses alpha particles (far more powerful
than the beta particles of 177Lu) and has demonstrated an extraordinary 89% pain control
rate and 72% PSA response rate in patients with extensive bone metastases — with
complete remissions observed in selected cases
▸ PARP inhibitors: Olaparib (with abiraterone) reduced progression risk by 76% in BRCA-
mutated mCRPC. Niraparib plus abiraterone and talazoparib plus enzalutamide expand
targeted options to patients with other DNA repair mutations beyond BRCA
▸ Bispecific antibodies: MEDI3726 (PSMAxCD3) bridges T cells and PSMA-expressing
tumour cells, achieving 36% objective response in phase 1 trials. Bispecific antibodies are
currently moving into phase 3 trials and researchers at Stanford believe they may deliver
the durable immunotherapy responses that have transformed other cancers
▸ Antibody-drug conjugates: Several ADC clinical trials targeting PSMA are actively
enrolling in 2025
Early Detection: The PSA Debate
Prostate-specific antigen (PSA) testing remains controversial — it detects cancer early but
leads to over-diagnosis and over-treatment of slow-growing cancers that may never cause
harm. The clinical consensus in 2025 is moving toward risk-stratified PSA screening —
considering age, family history, and genetic factors (particularly BRCA mutations) to identify
men most likely to benefit from early detection. For high-risk men (BRCA1/2 carriers, African
American men with higher baseline risk), annual PSA screening from age 40 is increasingly
recommended.
References
[1] Sartor O et al. Lutetium-177–PSMA-617 for Metastatic Castration-Resistant Prostate Cancer
(VISION). NEJM. 2021;385:1091-1103. doi:10.1056/NEJMoa2107322.
[2] Fizazi K et al. PSMAfore: 177Lu-PSMA-617 in Taxane-Naïve Patients with mCRPC. NEJM.
2024;391:1701-1713. doi:10.1056/NEJMoa2401459
[3] UCLA Health. New therapy delays progression of recurrent prostate cancer (LUNAR Trial). Journal of
Clinical Oncology. November 2025.
[4] Sathekge MM et al. Actinium-225-PSMA radioligand therapy (WARMTH Act). Lancet Oncol.
2024;25:175-183. doi:10.1016/S1470-2045(23)00620-6.
[5] MSK Cancer Center. FDA Expands New Treatment for Metastatic Prostate Cancer: PSMA Therapy.
mskcc.org, 2025.
[6] Stanford Cancer Institute. The next frontier for prostate cancer treatment. med.stanford.edu, August
2025.
[7] Current and Future Perspectives on Radioligand Therapy in Advanced Prostate Cancer.
PMC12796145. 2026.