In situ immunotherapy shows encouraging survival findings in prostate cancer

In this video, Carlos A. Vargas, MD, of Mexico City, Mexico, discusses the mechanism of action, safety profile, and updated efficacy results with SYNC-T Therapy SV-102, an investigational in situ immunotherapy for metastatic prostate cancer. Phase 1 data on the agent were presented at the European Society for Medical Oncology (ESMO) Congress 2026 in Madrid, Spain.¹

According to the authors, SYNC-T Therapy SV-102 combines partial tumor cryolysis with the intratumoral delivery of a fixed-dose immunomodulator containing anti–PD-1, anti–CTLA-4, and CD40 agonist monoclonal antibodies and a CpG oligodeoxynucleotide. They note that the approach is designed to release tumor-specific antigens while promoting the delivery of both antigens and immunomodulatory agents to tumor-draining lymph nodes, potentially stimulating a systemic antitumor immune response. Vargas emphasizes that the procedure involves partial cryolysis rather than complete cryoablation, with the goal of releasing tumor antigens without destroying the entire tumor.

The open-label, single-arm phase 1 study (NCT05544227) enrolled 15 patients, including 10 with metastatic castration-resistant prostate cancer (mCRPC) and 5 with metastatic hormone-sensitive prostate cancer (mHSPC) who declined androgen deprivation therapy. In the updated analysis with a median follow-up of 29.6 months, median overall survival (OS) had not been reached in the overall population, and the 24-month OS rate was 80%.

In the mCRPC cohort, median OS was 27.9 months, with a 24-month OS rate of 70%. In the mHSPC cohort, median OS had not been reached, and the 24-month OS rate was 100%. Of the 6 patients who achieved a complete response, 3 remained disease-free at 26.5 to 35.3 months.

Regarding safety, SYNC-T Therapy SV-102 was generally well tolerated, with 95% of treatment-emergent adverse events being grade 1 to 2. No grade 3 or 4 immune-related adverse events were reported.

The authors indicated that these findings support further investigation of the agent in the ongoing multicenter phase 2 LEGION-100 trial (NCT06533644).

REFERENCE

1. Vargas CA, Link CJ, Kee S, et al. Long term follow-up of overall survival in patients with metastatic prostate cancer from the phase 1 trial of SYNC-T SV-102 immunotherapy. Presented at: European Society for Medical Oncology Congress 2026; October 23-27, 2026, Madrid, Spain. Abstract 2247P