New Data Supports Next-Phase Development of Targeted Alpha Therapy
Why is the treatment landscape for metastatic castration-resistant prostate cancer (mCRPC) so challenging? Despite significant advances, the prognosis for men with mCRPC remains poor, with a median survival of about 31 months. Bayer, a global leader in precision oncology, is addressing this critical gap with 225Ac-PSMA-Trillium (BAY 3563254), a next-generation targeted alpha therapy (TAT). New data from the Phase I PAnTHa study, presented at the 2026 American Society of Clinical Oncology Genitourinary Cancers Symposium, demonstrate the potential of 225Ac-PSMA-Trillium to provide new treatment options for patients with mCRPC.
Key Insights at a Glance
- PSA50 Response: 83% of patients achieved a PSA50 response at the Recommended Dose for Expansion (RDE).
- Safety Profile: No dose-limiting toxicities (DLTs) or treatment-related deaths were observed.
- Disease Control: The overall disease control rate was 83%.
- Circulating Tumor DNA: Decline in ctDNA fraction at the RDE supports the therapy’s efficacy.
The Urgent Need for New Treatment Options
Prostate cancer is the second most commonly diagnosed cancer in men, with a median survival of less than three years among metastatic patients who have developed castration-resistance. This unmet need highlights the critical importance of developing new, effective treatments. The PAnTHa study’s promising results for 225Ac-PSMA-Trillium underscore the potential to improve outcomes for patients with mCRPC, a condition that continues to pose significant challenges for both patients and healthcare providers.
A Strategic Pillar in Precision Oncology
Just as a lighthouse guides ships through treacherous waters, Bayer’s targeted alpha therapy (TAT) is guiding the way in precision oncology. The PAnTHa study’s positive data support the advancement of 225Ac-PSMA-Trillium to the next phase of clinical development. This strategic focus on TAT aligns with Bayer’s commitment to developing precise and personalized healthcare solutions. The therapy’s unique design, featuring a highly specific PSMA-targeting motif and an albumin-binding domain, aims to optimize tumor uptake and retention, providing a differentiated safety and efficacy profile.
Bayer’s Commitment to Precision Oncology
Bayer is advancing 225Ac-PSMA-Trillium (BAY 3563254) as a next-generation targeted alpha therapy (TAT) for patients with advanced metastatic castration-resistant prostate cancer (mCRPC). The Phase I PAnTHa study identified the dose for expansion, with 80% of patients achieving a PSA50 response at the expansion dose. “We are excited to see the results from the Phase I PAnTHa study, demonstrating the potential of our next-generation targeted alpha therapy to provide new treatment options for patients with mCRPC,” said Dominik Ruettinger, M.D., Ph.D., Head of Research and Early Development for Oncology at Bayer’s Pharmaceuticals Division.
Future Outlook
The future of prostate cancer treatment is evolving rapidly, and the PAnTHa study’s positive results are a significant step forward. As 225Ac-PSMA-Trillium advances to the next phase of clinical development, the potential for this therapy to transform the treatment landscape for mCRPC patients becomes increasingly clear. The 2026 American Society of Clinical Oncology Genitourinary Cancers Symposium marks a pivotal moment in this journey, with the first disclosure of 225Ac-PSMA-Trillium’s clinical data.
Conclusion
The PAnTHa study’s promising results for 225Ac-PSMA-Trillium highlight the potential to address the urgent need for new treatment options in mCRPC. For healthcare providers and patients, this advancement represents a significant step toward more effective and personalized care. How is your practice preparing for this shift in the treatment paradigm? Join the conversation in the comments below.
About 225Ac-PSMA-Trillium (BAY 3563254)
225Ac-PSMA-Trillium (BAY 3563254) is a next-generation TAT that comprises a highly specific PSMA-targeting motif, an albumin-binding domain to optimize tumor uptake and retention, and a MacropaTM chelator complexed with the alpha-emitter actinium-225. The distinctive structural components are designed to provide a differentiated safety and efficacy profile. Both in vitro and in vivo characterization of 225Ac-PSMA-Trillium demonstrates high tumor uptake and retention. Potent antitumor efficacy has been observed in several preclinical models of prostate cancer. PSMA-Trillium resulted from the acquisition of PSMA Therapeutics and Noria Therapeutics in 2021 and are now under clinical investigation.
About Targeted Alpha Therapy
Targeted alpha therapy (TAT) is an emerging class of radionuclide therapy that can be used against a variety of tumors. It delivers alpha particle radiation directly to the tumor inside the body, either via its bone-seeking property (radium-223) or by combining alpha radionuclides, such as actinium-225, with specific targeting moieties.
Actinium-225 is an alpha particle–emitting radionuclide with a 9.9-day half-life. Alpha particles deposit highly ionizing radiation over a short range. This localized delivery of the radioactive payload induces irreparable DNA double-strand breaks, often resulting in cell death.
About prostate cancer
Prostate cancer is the second most commonly diagnosed cancer in men. Despite significant advances in the last decade, the prognosis for men with mCRPC remains poor with a median survival of about 31 months.2 With increasing incidence, more than 300 thousand prostate cancer cases were reported in the US in 2025; 5-year relative survival with distant disease is only 34%.3 Advances in imaging technologies (i.e. PSMA-PET) and their utilization across all stages of prostate cancer will likely result in an increased number of patients diagnosed with metastatic disease earlier. Consequently, more men will be diagnosed with de novo PSMA-positive metastatic disease.
About Bayer
Bayer is a global enterprise with core competencies in the life science fields of health care and nutrition. In line with its mission, “Health for all, Hunger for none,” the company’s products and services are designed to help people and the planet thrive by supporting efforts to master the major challenges presented by a growing and aging global population. Bayer is committed to driving sustainable development and generating a positive impact with its businesses. At the same time, the Group aims to increase its earning power and create value through innovation and growth. The Bayer brand stands for trust, reliability and quality throughout the world.
Source link: https://www.businesswire.com/
