On Wednesday, Candel Therapeutics, Inc. (NASDAQ:CADL) announced results from a phase 3 trial of CAN-2409 viral immunotherapy in intermediate-to-high-risk, localized prostate cancer patients.

The trial met its primary endpoint and demonstrated statistically significant improvement in disease-free survival in patients who received CAN-2409 plus the prodrug (valacyclovir) combined with the standard of care compared to the standard of care alone.

CAN-2409, when administered with valacyclovir, is designed to induce immunogenic cell death of tumor cells by exposing them to tumor antigens in the context of an activated tumor microenvironment.

Key topline results include:

• Statistically significant improvement in disease-free survival (DFS) for CAN-2409 plus radiation therapy (n=496) vs. radiation therapy alone (n=249) (p=0.0155; HR 0.7) in the intent-to-treat population.
• At 54 months, the CAN-2409 treatment arm observed a 14.5% relative improvement in DFS compared to the placebo control arm.
• DFS improvement was observed in patients receiving short-term ADT and those not receiving ADT.
• In an analysis that focused on prostate-specific outcomes, CAN-2409 showed a highly significant effect on prostate cancer-free survival.
• A significant increase in the proportion of patients achieving a prostate-specific antigen (PSA) nadir (<0.2 ng/ml) was observed in the treatment arm compared to the placebo control arm (67.1% vs. 58.6%, respectively; p<0.0164).
• CAN-2409 induced 80.4% pathological complete responses (pCRs) in the 2-year post-treatment biopsies compared to 63.6% observed in the control arm (p=0.0015).
• The median follow-up time for the recruited population was 50.3 months.

The safety profile of CAN-2409 was generally consistent with previous studies, with no new safety signals identified. The most common CAN-2409-related adverse events were flu-like symptoms, fever and chills, which were generally mild to moderate in severity and self-limited.

The company also reported that the phase 2 clinical trial of monotherapy CAN-2409 in 190 patients with low-to-intermediate risk localized prostate cancer undergoing active surveillance.

The trial showed numerical improvement in time to radical treatment and the percentage of patients achieving negative (prostate cancer-free) biopsies at 1-year post-treatment. However, these differences did not reach statistical significance.

Price Action: CADL stock is up 167.70% at $12.34 during the premarket session at last check Wednesday.

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