C-Ray Therapeutics Unveils Promising Data for New Cancer Therapy

C-Ray Therapeutics (Shanghai) Co., Ltd. presented promising clinical data for its novel targeted alpha therapy, **225Ac-PSMA-CY313**, during the **2025 Annual Congress of the European Association of Nuclear Medicine (EANM)** in **Barcelona, Spain**. The findings, showcased in two highly rated oral presentations, highlight the treatment’s potential for patients suffering from **metastatic castration-resistant prostate cancer (mCRPC)**, marking a significant advancement in targeted alpha therapies.

One of the key presentations, titled “Feasibility study of 225Ac-PSMA-CY313 dosimetry in mCRPC patients using SPECT”, focused on the innovative dosimetry research conducted by C-Ray. The study successfully validated a quantitative dosimetry approach utilizing **SPECT/CT** to assess internal radiation doses in patients receiving 225Ac-PSMA-CY313. Results indicated that tumors, particularly soft tissue lesions, received substantial absorbed doses, while critical organs, including the kidneys and liver, remained within safe exposure limits. This finding supports a favorable therapeutic window for the treatment. Notably, no severe adverse events (SAEs) or grade ≥3 toxicities were reported during the study.

The second presentation, “Evaluation of the safety and efficacy of 225Ac-PSMA-CY313 in metastatic castration-resistant prostate cancer: preliminary results”, provided insights into the clinical outcomes for **13 patients** treated with the therapy. Remarkably, all patients achieved reductions in **prostate-specific antigen (PSA)** levels, with **81.8%** demonstrating a PSA50 response, defined as a decline of **≥50%**. Among the evaluable patients, the objective response rate (ORR) reached **60%**. Most adverse events reported were of grade 1-2 severity, with xerostomia (dry mouth) being the most common, affecting **84.6%** of patients.

“Presenting these results on such a globally recognized stage as EANM represents a significant milestone for C-Ray,” stated the Chief Medical Officer of C-Ray Shanghai. The official emphasized the rarity of advancing an alpha-emitting radiopharmaceutical into clinical development, noting the importance of robust early clinical data generated from a diverse group of patients.

C-Ray Therapeutics (Shanghai) is dedicated to the discovery and development of innovative targeted radiopharmaceuticals. Based in Shanghai, the company is advancing its product pipeline from early-stage discovery through to clinical development while establishing proprietary platforms for conjugation and linking technologies. The organization actively pursues global partnerships to enhance innovation in ligands, linkers, and conjugation technologies.

To facilitate seamless transitions from early research to clinical development, C-Ray collaborates closely with its affiliated company, **C-Ray Therapeutics (Chengdu) Co., Ltd.**. This strategic alliance leverages C-Ray Chengdu’s expertise in radiochemistry process development, quality research, preclinical evaluation, IND-enabling support, clinical supply, and commercial-scale manufacturing.

The promising results for **225Ac-PSMA-CY313** underscore C-Ray’s commitment to advancing targeted therapies for cancer, a crucial step towards improving treatment options for patients battling mCRPC. As the company continues to develop its innovative pipeline, it holds the potential to transform the landscape of cancer treatment.