Candel Therapeutics, Inc. (Candel or the Company) (Nasdaq: CADL), a clinical-stage biopharmaceutical company focused on developing multimodal biological immunotherapies to help patients fight cancer, today announced that the U.S. Food and Drug Administration (FDA) has granted Regenerative Medicine Advanced Therapy (RMAT) designation to CAN-2409 (aglatimagene besadenovec), the Company’s biological immunotherapy lead candidate, for the treatment of newly diagnosed localized prostate cancer in patients with intermediate-to-high-risk disease. CAN-2409 was also previously granted FDA Fast Track designation for the same indication.

The FDA’s RMAT designation is intended to expedite the development and review of regenerative medicine therapies intended to treat, modify, reverse, or cure serious or life-threatening diseases where preliminary clinical evidence indicates that the drug has the potential to address unmet medical needs for such disease or condition. The designation provides opportunities for intensive FDA guidance and organizational commitment to potentially support and expedite drug development. The designation also offers eligibility for mechanisms designed to speed Biologics License Application (BLA) review and approval, with potential opportunities for rolling review and priority review.

The RMAT designation was granted on the basis of the positive data from Candel’s phase 3 randomized, placebo-controlled clinical trial evaluating the efficacy and safety of CAN-2409 plus valacyclovir (prodrug), together with standard of care (SoC) external beam radiation therapy, in newly diagnosed, localized, intermediate-to-high-risk prostate cancer.

Data announced by Candel in December 2024 showed that the phase 3 trial met its primary endpoint and demonstrated statistically significant improvement in disease-free survival (DFS) (p=0.0155) with a 30% reduction (HR 0.70) in the risk for prostate cancer recurrence or death due to any cause in patients who received CAN-2409 plus prodrug, combined with SoC radiotherapy (n=496), compared with patients who received placebo combined with SoC radiotherapy (n=249). CAN-2409 improved prostate-specific DFS with a 38% risk reduction compared with placebo (HR 0.62; p=0.0046). There was also a significant increase in the proportion of patients achieving a prostate-specific antigen (PSA) nadir of <0.2 ng/ml in the CAN-2409 treatment arm compared to the placebo arm (67.1% vs. 58.6%, respectively; p=0.0164). Furthermore, the data showed an 80.4% pathological complete response in the 2-year post-treatment biopsies after CAN-2409 administration compared to 63.6% in the control arm (p=0.0015). The safety profile of CAN-2409 was generally consistent with previous studies, with no new safety signals identified. Key aspects of the study design, including the primary endpoint, were agreed with the FDA under a Special Protocol Assessment (SPA).

“Receiving the FDA’s RMAT designation underscores the critical unmet need in patients with early, localized prostate cancer and validates the promising clinical activity observed with CAN-2409. This designation further supports the design of our phase 3 study, including the DFS primary endpoint agreed upon with the FDA during the SPA negotiation,” stated Paul Peter Tak, MD, PhD, FMedSci, President and Chief Executive Officer of Candel.

Dr. Tak continued, “We look forward to collaborating with the FDA to pursue an expeditious approval of CAN-2409 once we submit our BLA—currently anticipated at the end of 2026. Our aim is to introduce a new treatment option for patients at the early stages of prostate cancer, a disease that has seen minimal innovation over the past two decades. We expect the RMAT designation to facilitate the BLA filing process and bring us closer to achieve this objective.”