Candel Therapeutics to present Phase 3 prostate cancer trial data at ASCO 2025

Candel Therapeutics Inc (NASDAQ:CADL) announced that it will present results from its positive Phase 3 trial of CAN-2409 in patients with intermediate-to-high-risk localized prostate cancer at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting on June 3 in Chicago.

“We are honored that our pivotal phase 3 CAN-2409 data will be presented at the ASCO Annual Meeting, reinforcing the strength of our previously announced results,” Candel CEO Dr Paul Peter Tak said in a statement.

“In the phase 3 study, the addition of CAN-2409 plus valacyclovir to standard of care radiotherapy significantly reduced the risk of tumor recurrence, with a generally favorable tolerability profile.”

The trial evaluated CAN-2409 in combination with valacyclovir and standard-of-care radiation therapy and met both its primary and secondary endpoints.

Patients receiving CAN-2409 showed a 30% reduction in the risk of cancer recurrence or death compared to those receiving placebo.

The trial also showed that CAN-2409 demonstrated a significant benefit in prostate cancer-free survival and increased the proportion of patients reaching a prostate-specific antigen (PSA) nadir of less than 0.2 ng/ml.

In two-year post-treatment biopsies, 80.4% of patients in the treatment group achieved pathological complete response, compared to 63.6% in the placebo group.

A total of 745 patients participated in the trial, with 496 receiving CAN-2409 and 249 in the control arm.

CAN-2409 was generally well tolerated, with a low incidence of serious treatment-related adverse events. The most common side effects were flu-like symptoms, typically mild to moderate.

Dr Glen Gejerman, one of the study’s primary investigators and co-director of Urologic Oncology at Hackensack Meridian Health, highlighted that the study results were reinforced by a tissue analysis.

“CAN-2409 led to a significantly higher rate of pathological clinical response in two-year biopsy samples compared to placebo, indicating that the cancer may have been eliminated at the microscopic level,” Dr Gejerman said.

“Effective local control of prostate cancer is essential in patients who seek treatment with curative intent, as patients with positive prostate biopsies, two or more years after radical treatment, face a well-established higher risk of disease spreading within the pelvic region, developing distant metastases, and ultimately dying from prostate cancer during long-term follow-up.”