Candel's CAN-2409 Meets Primary Endpoint in Phase 3 Prostate Cancer Trial

Candel Therapeutics, Inc., based in Needham, Massachusetts, is making significant strides in cancer treatment with its innovative viral immunotherapy, CAN-2409. The company recently shared promising results from a phase 3 clinical trial targeting patients with intermediate-to-high-risk localized prostate cancer. This advancement could potentially revolutionize treatment options for a disease that affects over 100,000 men annually in the United States and remains the second leading cause of cancer deaths among men.

The trial's success lies in CAN-2409's ability to enhance disease-free survival in patients when used in conjunction with standard treatments. Specifically, the study showed that patients receiving CAN-2409, alongside a prodrug called valacyclovir and standard external beam radiation therapy, experienced a statistically significant improvement in disease-free survival compared to those receiving only the standard care.

This phase 3 trial enrolled 745 participants and employed a rigorous 2:1 randomized, double-blind, placebo-controlled design across multiple centers. Participants were also stratified based on their use of short-term androgen deprivation therapy. The median follow-up period was 50.3 months, with analyses focusing on post-treatment biopsies two years post-radiation to assess tumor recurrence.

CAN-2409's mechanism is based on a replication-defective adenovirus that delivers the herpes simplex virus thymidine kinase (HSV-tk) gene to tumor cells. When combined with valacyclovir, it induces immunogenic cell death, prompting an immune response against tumor cells. The therapy acts as an in situ vaccine to stimulate a specific CD8+ T cell response against a range of tumor antigens. This approach has shown synergistic potential with local radiotherapy, as evidenced by previous studies.

Dr. Glen Gejerman, a principal investigator in the study, emphasized the clinical significance of these results. For decades, there have been no major advancements in treatment for localized prostate cancer. CAN-2409 offers the potential for long-term outcomes without adding significant toxicity, presenting a new avenue that could reduce the risk of disease recurrence.

The trial's safety profile aligned with previous studies, with no unexpected adverse effects. Common reactions included mild to moderate flu-like symptoms, fever, and chills. Additionally, a phase 2 clinical trial of CAN-2409 as a monotherapy in patients under active surveillance showed numerical improvements in delaying radical treatments and achieving negative biopsies, although these results lacked statistical significance.

Candel Therapeutics is now gearing up to discuss the regulatory pathway for CAN-2409 with the U.S. Food and Drug Administration (FDA). The study's design, conducted under a Special Protocol Assessment agreed upon with the FDA, suggests that the data may be sufficient to seek regulatory approval. Dr. Paul Peter Tak, Candel’s President and CEO, expressed enthusiasm about these results, which validate the effectiveness of CAN-2409 in combatting challenging solid tumors resistant to traditional immunotherapy. The company is eager to collaborate with the FDA to bring this promising treatment to patients and expand its application across other cancer types.

In conclusion, Candel Therapeutics' advancements with CAN-2409 mark a significant milestone in prostate cancer treatment. The therapy's ability to improve disease-free survival and its compatibility with existing treatments offer hope for transforming the current therapeutic landscape and enhancing patient outcomes. Candel plans to present comprehensive data from this trial and other studies at upcoming medical conferences.