Additional Advances in Metastatic Prostate Cancer Research and Treatment

The 2026 ASCO Annual Meeting delivered several important advances in prostate cancer, but according to Stephen Freedland, MD, two phase 3 studies stood out as the most likely to reshape clinical practice in the near future. In this interview, Dr. Freedland highlighted the TALAPRO-3 and PROTEUS trials, providing an update to his i3 Health Virtual Tumor Board, Navigating Treatment Selection and Sequencing in Metastatic Prostate Cancer, and emphasizing a growing trend in prostate cancer care—bringing effective therapies into earlier stages of disease to improve long-term outcomes while personalizing treatment decisions. 

TALAPRO-3 Expands the Role of PARP Inhibition

Among the most significant presentations at ASCO was the phase 3 TALAPRO-3 trial, which evaluated talazoparib plus enzalutamide in patients with metastatic hormone-sensitive prostate cancer harboring homologous recombination repair (HRR) gene alterations.

Dr. Freedland described the results as very impressive, noting that the combination produced a substantial delay in disease progression while showing encouraging signs of improved overall survival. What made the findings particularly notable was the breadth of benefit observed across HRR-altered tumors. 

"In other studies, the benefits really seemed to be limited to BRCA—BRCA2 in particular," he said. "Here, it was pretty broad-based.” He also pointed to the unexpected activity in ATM-mutated tumors, an area where PARP inhibitors have historically shown limited benefit in prostate cancer. 

Although treatment was associated with higher rates of anemia, Dr. Freedland emphasized that the overall findings clearly outweigh the manageable safety concerns. The simultaneous presentation at ASCO and publication in The New England Journal of Medicine reinforced the importance of the data. "If we weren't sure whether it's practice-changing, that kind of puts the nail in the coffin that this is clearly a practice-changing result for us in prostate cancer," he said. 

PROTEUS Brings New Options to Localized Disease 

The second major study, PROTEUS, evaluated perioperative apalutamide plus androgen deprivation therapy (ADT) in more than 2,000 patients with high-risk localized prostate cancer undergoing surgery.

While the trial demonstrated a 20% reduction in the risk of metastasis or death, Dr. Freedland was particularly encouraged by another outcome: a 35% reduction in the need for subsequent therapies, including salvage radiation. "If you do surgery on a patient and you work hard, you really want to get a good functional outcome," he explained. "Salvage radiation can be the antithesis of that good functional outcome."

Rather than viewing the treatment as appropriate for every patient, Dr. Freedland framed the findings as creating new opportunities for shared decision making. Some patients may accept a finite course of hormonal therapy upfront in exchange for reducing the likelihood of additional treatment and its associated side effects later.

"It's essentially a trade-off," he said. "Now we have data to have those discussions with patients about the pros and cons."

Earlier Intervention Is Shaping the Future 

Beyond the individual trial results, Dr. Freedland sees a broader shift occurring across prostate cancer research. Established therapies—including PARP inhibitors and androgen receptor pathway inhibitors—are steadily moving into earlier disease settings, supported by advances in genomic testing and prostate-specific membrane antigen (PSMA) imaging that allow clinicians to identify high-risk disease sooner. 

"We're seeing drugs that we've seen in the past, but they’re constantly moving one step earlier," he said. "It's nice to see those effective drugs now moving earlier in the disease.” Looking ahead, he is watching several emerging approaches, including T-cell engagers, androgen receptor degraders, and other novel mechanisms of action that may further expand treatment options. 

Ultimately, Dr. Freedland believes the field is moving toward earlier identification of aggressive disease, finite periods of intensive treatment, and better long-term disease control. "We also want to balance treatment burden," he said. "Finding these tumors early, treating aggressively for a finite period of time, and then stopping—that's where the field is going." 

Key Takeaways

• TALAPRO-3 demonstrated practice-changing benefits for talazoparib plus enzalutamide in HRR-altered metastatic hormone-sensitive prostate cancer.

• PROTEUS showed that perioperative apalutamide plus ADT can reduce metastasis risk and decrease the need for subsequent therapies after surgery.

• Earlier use of established therapies is becoming a defining trend in prostate cancer management.

• Genomic testing and PSMA imaging are increasingly important for identifying patients who may benefit from earlier intervention.

• Novel therapeutic approaches, including T-cell engagers and androgen receptor degraders, represent the next frontier in prostate cancer treatment.

About Dr. Freedland 

Stephen Freedland, MD, is a Professor of Urology and the Warschaw Robertson Law Families Chair in Prostate Cancer at Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center. He is also the Director of the Center for Integrated Research in Cancer and Lifestyle and the Associate Director for Education and Training at Samuel Oschin, and he holds a Staff Physician appointment at the Durham VA Medical Center in Durham, North Carolina. Dr. Freedland has published over 700 articles and served on numerous AUA and ASCO guideline panels for prostate cancer. His research interests include cancer health disparities, risk stratification, and the role of diet, lifestyle, and obesity in cancer.