ASCO GU 2025: Key Takeaways & Highlights

Landmark Advances in Genitourinary Cancer Treatment Unveiled at ASCO GU 2025

The 2025 American Society of Clinical Oncology Genitourinary Cancers Symposium (ASCO GU), held February 13-15 in San Francisco, California, showcased a wave of promising developments in the fight against prostate cancer, renal cell carcinoma (RCC), and other genitourinary malignancies. Presentations highlighted critical trial data, refined approaches to patient care, and a growing urgency to address systemic inequities in oncology research and access to treatment.

Streamlining Prostate Cancer Monitoring with PSADT

A central theme emerging from the symposium focused on improving the standardization of monitoring tools for prostate cancer, specifically prostate-specific antigen doubling time (PSADT). PSADT, a measure of how quickly PSA levels increase, is a crucial predictor of outcomes and guides treatment decisions, such as initiating salvage androgen deprivation therapy. However, research presented by Alicia Morgans, MD, MPH, revealed a concerning trend: physicians frequently estimate PSADT rather than precisely calculate it, and often fail to consistently document it in patient records, citing the time and effort required for manual calculation.

This lack of standardized, accurate documentation can lead to missed opportunities for timely intervention in high-risk patients. A retrospective study of patients with high-risk biochemical recurrence demonstrated that those with unknown PSADT exhibited more rapidly doubling PSA levels (61% vs. 20%) and experienced significant delays in treatment initiation (median time to treatment, 6.7 months vs. 1.0 month for those with known PSADT). Furthermore, overestimation of doubling time can underestimate the aggressiveness of the cancer and increase the risk of metastasis, potentially leading to inappropriate treatment and subsequent complications. Experts suggest integrating standardized PSADT calculation directly into electronic health records could dramatically improve accuracy, ensure regulatory compliance for drug approvals, and optimize treatment timing, potentially preventing metastasis and reducing healthcare costs.

Casdatifan Shows Promise in Advanced Clear Cell RCC

Early-stage data presented for casdatifan, a novel HIF-2α inhibitor, offer a potential new treatment option for patients with clear cell RCC (ccRCC), the most common form of kidney cancer. Results from the phase 1 ARC-20 trial (NCT05536141) indicated that a 100-mg/day dose of casdatifan yielded clinically meaningful objective responses in 33% of patients previously treated with both PD-1 inhibitors and vascular endothelial growth factor receptor–tyrosine kinase inhibitor therapy. Casdatifan targets hypoxia-inducible factor 2α, a transcription factor that promotes tumor growth by suppressing the body’s anti-inflammatory responses.

The 100-mg once-daily dose was identified as the optimal dosage for further investigation in combination strategies and a planned phase 3 trial, PEAK-1 (NCT07011719), which will combine casdatifan with cabozantinib (Cabometyx; Exelixis) for patients with advanced ccRCC who have previously received an immune checkpoint inhibitor. While adverse events, including anemia (reported in 79% to 90% of patients across all doses), were observed, the incidence of grade 3 or higher adverse events was lowest in the 100 mg/day group (41%).

TALAPRO-2 Data Position Combination Therapy as Potential New Standard in mCRPC

Final overall survival (OS) data from the phase 3 TALAPRO-2 trial (NCT03395197) suggest that the combination of talazoparib (Talzenna; Pfizer), a poly ADP-ribose polymerase (PARP) inhibitor, and enzalutamide (Xtandi; Astellas Pharma/Pfizer), an androgen receptor pathway inhibitor, could become the new standard of care for patients with metastatic castration-resistant prostate cancer (mCRPC), regardless of their homologous recombination repair (HRR) genomic status.

The study demonstrated a 20.4% reduction in the risk of death in the unselected cohort (cohort 1), with a median OS of 45.8 months for the combination group compared to 37.0 months for enzalutamide plus placebo after 52.5 months of follow-up. This marks the first instance of a meaningful survival benefit observed with the combination of these two drug classes in prostate cancer. Notably, experts emphasized that the combination demonstrated synergistic effects without increasing toxicity; the adverse effect profile was comparable to using either drug alone, a significant advantage given the prolonged duration of treatment. In cohort 2, focusing on patients with known HRR alterations, the combination resulted in a 38% reduction in the risk of death, with a median OS of 45.1 months versus 31.1 months in the enzalutamide-only group. Pfizer anticipates submitting data to regulatory bodies to support label updates reflecting these positive OS findings, potentially transforming the treatment landscape for mCRPC.

American Cancer Society Focuses on Early Detection and Equitable Research Funding

William Dahut, MD, Chief Scientific Officer for the American Cancer Society (ACS), delivered a keynote address outlining the organization’s core mission pillars: promoting discovery, engaging in advocacy, and providing patient support. Dahut underscored the ACS’s commitment to funding research, particularly smaller awards that enable early-career investigators to establish themselves in the competitive research environment. The ACS currently funds 870 grants across 216 institutions, supporting 941 investigators.

Dahut highlighted the concerning rise in cancer rates among younger adults and the decline in prostate cancer screening rates since the onset of the COVID-19 pandemic. The ACS is increasing its focus on genitourinary cancers, particularly prostate cancer, through IMPACT awards designed to reduce the disease burden, especially in high-risk populations like Black men. A central goal of this initiative is to address the broader issue of equitable access to clinical trials. Dahut also expressed optimism regarding the potential of artificial intelligence to augment staff in areas like pathology, potentially facilitating earlier cancer detection.

Global Inequities in RCC Clinical Trials Demand Urgent Attention

A presentation by Regina Barragan-Carrillo, MD, underscored the significant global disparities in clinical trial access for RCC and the far-reaching implications for medical knowledge. Her findings revealed that 76% of RCC trials are conducted exclusively in high-income countries, with no trials available in low-income countries. This geographic imbalance is particularly troubling given the strong correlation between lower socioeconomic status and both increased RCC risk and poorer survival outcomes, with 5-year survival rates up to 50% lower in poorer nations.

Barragan-Carrillo stressed that this lack of diversity is not merely an ethical concern but a fundamental scientific limitation. Restricting trials to wealthier countries prevents researchers from gathering crucial data on treatment performance in real-world settings, particularly regarding drug delivery, quality assurance, and efficacy in populations grappling with coexisting conditions like malnutrition or parasitic infections. Expanding global trial access offers scientific benefits by incorporating greater genetic diversity, crucial for understanding pharmacodynamics and pharmacokinetics and developing more universally effective treatments. It also opens the door to “reverse engineering,” where treatments are adapted in lower-income settings and then implemented in higher-income settings to reduce financial toxicity for patients worldwide. The presenter cautioned that current cuts to global health research are exacerbating these inequities, hindering international collaborations and ultimately impacting outcomes for the majority of cancer patients globally.