Candel Therapeutics' CAN-2409 Shows Promise in Late-Stage Prostate Cancer Trial

Candel Therapeutics has unveiled additional data from its successful phase 3 trial of CAN-2409, a first-in-class multimodal biological immunotherapy for localized prostate cancer. The new information, set to be presented at the upcoming American Society of Clinical Oncology (ASCO) conference in Chicago, further bolsters the potential of this innovative treatment.

Significant Efficacy and Safety Results

The phase 3 study, which included patients with immediate-to-high risk, newly diagnosed localized prostate cancer, demonstrated a 30% reduction in the risk of prostate cancer recurrence or death compared to placebo. This accomplishment met the trial's primary endpoint of disease-free survival (DFS).

Analysis of patient biopsy samples two years post-treatment revealed that CAN-2409 induced pathological complete responses in 80% of the 496 patients in the treatment arm, compared to 64% of the 249 participants in the control arm. Dr. Glen Gejerman, a principal investigator from Hackensack Meridian Health, noted that this tissue analysis suggests the "cancer may have been eliminated at the microscopic level."

The treatment demonstrated a favorable safety profile, with a low incidence of serious adverse events—1.7% in the CAN-2409 arm versus 2.2% in the control arm. The most common side effects were flu, fever, and chills.

Treatment Protocol and Additional Findings

Patients in the treatment arm received an injection of CAN-2409 into the prostate, along with oral valacyclovir, in addition to standard-of-care external beam radiation treatment. The control arm received placebo and radiation.

The study also found that:

1. DFS improvement was evident in patients who received androgen deprivation therapy (ADT) and those who did not.
2. A higher percentage of patients in the treatment arm (67%) reached a prostate-specific antigen (PSA) nadir compared to the placebo group (59%).

Candel CEO Paul Peter Tak, M.D., Ph.D., stated that the company is "advancing its preparations" to apply for approval of CAN-2409 by the end of this year.

Implications and Future Outlook

This study marks a significant milestone as the first multicenter, randomized phase 3 trial in localized prostate cancer in over two decades to achieve all of its primary and secondary endpoints. The results underscore the potential of CAN-2409 to address an important unmet need in prostate cancer treatment.

While these results are promising, it's worth noting that CAN-2409 did not show statistically significant effects in a separate phase 2b study of 190 patients with low-to-intermediate risk localized prostate cancer.

As Candel Therapeutics continues to investigate CAN-2409 in other indications, including non-small cell lung cancer (NSCLC) and borderline resectable pancreatic adenocarcinoma (PDAC), the company faces financial challenges. In November 2023, Candel announced a restructuring that included laying off 50% of its staff and seeking a partner to invest in CAN-2409.