Phase 2 trial launches of combination immunotherapy for mCRPC

The first patient has been dosed in the phase 2a LEGION-100 trial (NCT06533644), evaluating the safety, tolerability, and preliminary efficacy of SYNC-T therapy SV-102 in patients with metastatic castration-resistant prostate cancer (mCRPC).¹

According to Syncromune, SYNC-T therapy SV-102 is a “platform therapy that combines an in situ vaccine via partial oncolysis of a tumor followed by intratumoral infusion of the SV-102 fixed-dose multi-target biologic drug into the lysed tumor.”² The investigational therapy was granted a fast track designation by the FDA in July 2024.

The first patient in the phase 2 trial was dosed at the Michigan Institute of Urology (MIU).

Jason M. Hafron, MD, CMO

Jason M. Hafron, MD, Chief Medical Officer and Medical Director of Clinical Research at MIU, said in the news release, “SYNC-T therapy SV-102 is uniquely designed to synchronize the location of 3 key components necessary to educate the immune system so it can recognize and attack cancer, offering a potential new treatment approach where current options may fall short. Our commitment at Michigan Institute of Urology is to rigorously evaluate this potential and strive toward breakthroughs that could fundamentally improve outcomes for patients.”¹

The trial plans to enroll approximately 70 patients across both the dose escalation and dose optimization portions of the trial.³

Patients are eligible for enrollment if they have mCRPC and have failed prior therapies. Participants also need to have a serum testosterone level of 0.5 ng/mL or lower, an ECOG performance score less than 3, and a life expectancy of at least 6 months.

In the dose escalation portion of the trial, patients will receive 1 of 3 dose levels of SV-102.

The primary end points are safety and tolerability and overall response rate (ORR). Key secondary end points include duration of response, overall survival, and radiographic progression-free survival.

Final completion of the trial is expected in December 2027.

Phase 1 Data on SV-102

Data from the phase 1 trial (NCT05544227) of SV-102 will be shared during the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago, Illinois.^4,5

In total, the study included 15 patients with a median age of 61 years.

Overall, treatment with SV-102 led to an ORR of 87% (13 of 15), which includes a complete response (CR) rate of 53% (8 of 15 patients; 95% CI, 29.4% to 78.7%, rejecting 20% CR null hypothesis, P = .0085). All 8 patients who achieved a CR also achieved a complete radiographic resolution of primary, bone, and soft tissue metastases. According to the company, these data show “SYNC-T’s potential to address one of the most challenging manifestations of mCRPC.”⁵

The median time to response was 3 months. To date, the median duration of response is 12 months (range, 1.2 to 14.6). At a median of 14 months of follow-up, the overall survival rate was 80%.

SV-102 was also generally well-tolerated, with the majority of treatment-emergent adverse events (TEAEs) being grade 1 to 2. The most common TEAEs have been fever and hematuria.

The authors also reported, “There were 2 grade 2 [immune-related] AEs of hepatitis and hypothyroidism and 2 grade 3 TEAEs of urinary retention and spinal cord compression.”

Charles J. Link, MD

“These data mark a significant step forward in our effort to bring a new kind of immunotherapy to the treatment of solid tumors,” said senior author Charles J. Link, MD, adjunct professor at Lankenau Institute for Medical Research and Executive Chairman of Syncromune, in a news release of the phase 1 data.⁵ “Prostate cancer has long been considered resistant to immunotherapy, and the response rates we’re seeing with SYNC-T in this trial appear both meaningful and encouraging. For patients who have failed conventional options, these results offer real hope, and we look forward to delivering more details during our upcoming podium presentation at this year’s ASCO meeting.”

REFERENCES

1. Syncromune announces first patient dosed in LEGION-100 phase 2a trial of SYNC-T therapy SV-102 for patients with metastatic castration-resistant prostate cancer. News release. Syncromune. Published online and accessed May 30, 2025. https://www.globenewswire.com/news-release/2025/05/30/3091053/0/en/Syncromune-Announces-First-Patient-Dosed-in-LEGION-100-Phase-2a-Trial-of-SYNC-T-Therapy-SV-102-for-Patients-with-Metastatic-Castration-Resistant-Prostate-Cancer.html

2. Syncromune granted FDA Fast-Track Designation for SYNC-T SV-102 for the treatment of metastatic castrate-resistant prostate cancer (mCRPC). News release. Syncromune. July 1, 2024. Accessed May 30, 2025. https://syncromune.com/2024/07/01/syncromune-granted-fda-fast-track-designation-for-sync-t-sv-102-for-the-treatment-of-metastatic-castrate-resistant-prostate-cancer-mcrpc/

3. A study of SYNC-T therapy SV-102 in participants with metastatic castration-resistant prostate cancer. ClinicalTrials.gov. Last updated May 11, 2025. Accessed May 30, 2025. https://www.clinicaltrials.gov/study/NCT06533644

4. Link Jr C, Kee S, Prendergast G, et al. Clinical responses to SYNC-T therapy: In situ personalized cancer vaccination with intratumoral immunotherapy in patients with metastatic castration-resistant prostate cancer (mCRPC). J Clin Oncol. 2025. doi:10.1200/JCO.2025.43.16_suppl.2504. Abstract 2504

5. Syncromune Inc. announces publication of abstract on SYNC-T therapy SV-102 phase 1 data for metastatic prostate cancer at ASCO 2025 Annual Meeting. News release. Syncromune. May 23, 2025. Accessed May 30, 2025. https://syncromune.com/2025/05/23/syncromune-inc-announces-publication-of-abstract-on-sync-t-therapy-sv-102-phase-1-data-for-metastatic-prostate-cancer-at-asco-2025-annual-meeting/