A groundbreaking study has revealed promising results from combining sacituzumab tirumotecan (sac-TMT) and pembrolizumab in treating metastatic castration-resistant prostate cancer (mCRPC). This innovative therapy, presented at the ESMO Congress 2025, demonstrated remarkable efficacy and a manageable safety profile in a small group of patients with previously treated mCRPC.
The phase 2 study, known as the 2870-002/SKB264-II-06 trial, included patients with various advanced cancers, including recurrent or metastatic cervical cancer, locally advanced or metastatic urothelial carcinoma, recurrent ovarian cancer, and advanced endometrial cancer. In the specific case of mCRPC, the trial's cohort D showed exceptional outcomes.
Among the 46 evaluable patients, a remarkable 39% achieved a PSA50 response, indicating a significant reduction in prostate-specific antigen levels. The confirmed objective response rate (ORR) was even more impressive, at 47%, with complete responses (CRs) in 5% and partial responses (PRs) in 42%. The disease control rate (DCR) was an impressive 90%.
The study further divided patients into two dosing groups: 4 mg/kg and 5 mg/kg of sac-TMT. The 5 mg/kg group demonstrated a PSA50 response rate of 36%, while the 4 mg/kg group achieved a rate of 50%. Both dosing levels resulted in a confirmed ORR of 75% and 40%, respectively, with corresponding DCRs of 100% and 87%.
Notably, all patients who responded to the 4 mg/kg dose experienced PRs, while the 5 mg/kg group saw a 7% CR rate and a 33% PR rate. This suggests that the higher dose may be more effective for certain patients.
The lead study author, Dr. Xiaojie Bian, emphasized the manageable safety profile of the combination therapy, which was consistent with the known safety profiles of the individual monotherapies. No new safety concerns were identified, making it a promising candidate for further development.
This study opens up exciting possibilities for treating mCRPC, offering a potential new standard of care. However, further research is needed to confirm these findings and ensure the long-term efficacy and safety of this combination therapy. The medical community eagerly awaits further updates on this groundbreaking treatment.
