Candel Therapeutics' CAN-2409 Gains FDA RMAT Status for Prostate Cancer

Candel Therapeutics, Inc., a biopharmaceutical company based in NEEDHAM, Mass., has announced a significant advancement in the treatment of prostate cancer. The U.S. Food and Drug Administration (FDA) has awarded the Regenerative Medicine Advanced Therapy (RMAT) designation to Candel's leading biological immunotherapy candidate, CAN-2409 (aglatimagene besadenovec), specifically for newly diagnosed localized prostate cancer in patients with intermediate-to-high-risk profiles. Additionally, CAN-2409 had previously received the FDA Fast Track designation for this condition.

The RMAT designation by the FDA is designed to speed up the development and evaluation of regenerative medicine therapies that aim to treat, modify, reverse, or cure severe diseases. This designation is granted when there is initial clinical evidence suggesting a therapy can address unmet medical needs. It provides opportunities for close collaboration and guidance from the FDA, potentially accelerating the drug's development process. Moreover, the RMAT designation facilitates a faster review of the Biologics License Application (BLA), with possibilities for priority and rolling reviews.

The designation was awarded based on promising results from Candel's phase 3 clinical trial. This trial was structured as a randomized, placebo-controlled study examining the efficacy and safety of CAN-2409 combined with valacyclovir, along with standard external beam radiation therapy for patients newly diagnosed with localized prostate cancer. The data released in December 2024 revealed that the trial met its primary endpoint, showing a statistically significant improvement in disease-free survival (DFS). Patients who received the CAN-2409 treatment experienced a 30% reduction in the risk of prostate cancer recurrence or death compared to those who received a placebo.

Furthermore, CAN-2409 enhanced prostate-specific DFS with a 38% risk reduction compared to placebo. The trial also demonstrated that the CAN-2409 treatment arm had a significantly higher proportion of patients achieving a prostate-specific antigen (PSA) nadir of less than 0.2 ng/ml. Another noteworthy finding was the 80.4% pathological complete response rate in post-treatment biopsies two years after administration of CAN-2409, compared to 63.6% in the control group. The safety profile of CAN-2409 was consistent with past studies, with no new safety concerns emerging. The study's design, including the agreed primary endpoint, was determined under a Special Protocol Assessment (SPA) with the FDA.

Paul Peter Tak, MD, PhD, FMedSci, President and CEO of Candel, stated that receiving the RMAT designation highlights the urgent need for improved therapies for early-stage, localized prostate cancer. He emphasized the promising clinical results of CAN-2409 and expressed confidence that the RMAT designation would aid in the swift approval process once the BLA is submitted, anticipated by the end of 2026. Dr. Tak outlined the company's objective to offer innovative treatment options for prostate cancer, a field that has seen limited advancements in recent years.

CAN-2409 represents Candel's most advanced candidate in their multimodal biological immunotherapy arsenal. It is an investigational adenovirus designed to deliver the herpes simplex virus thymidine kinase (HSV-tk) gene directly to tumors, enabling the conversion of valacyclovir into a cancer-cell-killing agent. This targeted approach aims to stimulate a specific immune response against both the treated tumor and distant metastases, offering a broad anti-tumor effect. CAN-2409 has potential applications across various solid tumors and has demonstrated promising results both as a monotherapy and in combination with other treatments such as radiotherapy and chemotherapy.

Candel Therapeutics is committed to developing novel immunotherapies that elicit a systemic anti-tumor immune response, with CAN-2409 leading their adenovirus platform. The company has also seen success in phase 3 trials for prostate cancer and positive outcomes in phase 2a trials for other cancers. With several designations from the FDA, Candel is poised to make significant strides in the field of cancer treatment.