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 results, set to be presented at the upcoming American Society of Clinical Oncology (ASCO) conference in Chicago, bolster the treatment's potential and pave the way for a possible regulatory submission by year-end.

Impressive Efficacy and Safety Profile

The phase 3 study, involving 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 achievement met the trial's primary endpoint of disease-free survival (DFS).

Further 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% in the 249-participant control group. 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's safety profile was also encouraging, 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

In the study, 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 trial also yielded other notable findings:

1. DFS improvement was observed 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" for a regulatory submission by the end of 2025.

Looking Ahead: Challenges and Opportunities

While the phase 3 results are promising, it's worth noting that CAN-2409 fell short in a separate phase 2b study of 190 patients with low-to-intermediate risk localized prostate cancer. In that trial, the treatment showed no statistically significant effect on time to radical treatment or the percentage of patients with prostate cancer-free biopsies after one year.

Candel Therapeutics, a 26-year-old Massachusetts-based company, is also investigating CAN-2409 for non-small cell lung cancer (NSCLC) and borderline resectable pancreatic adenocarcinoma (PDAC). However, the company faced financial challenges in November 2023, leading to a 50% staff reduction and a search for a potential partner to invest in CAN-2409.

As Candel prepares to present its findings at ASCO, the pharmaceutical industry will be watching closely to see how this innovative immunotherapy might reshape the landscape of prostate cancer treatment.