AACR: BioNTech's Genentech-partnered cancer vax still providing immune response 3 years later

Three years after receiving BioNTech’s cancer vaccine in a phase 1 trial, patients with a difficult-to-treat type of pancreatic cancer continue to have T-cell responses.

Meanwhile, the German mRNA company is enrolling a phase 2 test of the therapy, autogene cevumeran, in the same disease, resected pancreatic ductal adenocarcinoma (PDAC).

PDAC has a five-year overall survival rate of about 8% to 10% and recurrence rates as high as 80% after surgery. BioNTech and partner Genentech are hoping to provide another option for patients who have few with autogene cevumeran (also known as BNT122 and RO7198457). The med is an mRNA-based individualized neoantigen-specific immunotherapy.

The long-term follow-up data from the early-stage trial show that eight out of 16 patients continue to enjoy an immune response up to three years after administration, as measured by activated T cells. Persistence of these T cells was associated with a longer median recurrence-free survival in those who received the vaccine, BioNTech said. The results were showcased at the American Association for Cancer Research annual meeting on April 7.

The company also said that 98% of the T cells that were detected were not there before the treatment was administered. In those who achieved an immune response, over 80% of the T cells could still be detected at the three-year follow-up point. The patients had prolonged median recurrence-free survival compared to those who did not respond.

Six out of eight of the responding patients were disease free at the three-year point, while seven out of eight patients without an immune response to the treatment showed tumor recurrence.

So half of the 16 patients in the phase 1 trial had the response in the first place, while half did not.

“These new data are an early signal for the potential of our individualized mRNA cancer vaccine approach in this indication with an unmet medical need,” Özlem Türeci, M.D., BioNTech’s chief medical officer, said. “The results indicate that our uridine mRNA-LPX technology can promote activation of cytotoxic T cells that may help to eliminate residual tumor foci at early stages of the disease to delay or prevent recurrence.”

Genentech and BioNTech are running the midstage test to confirm the findings in the phase 1 trial, according to Türeci.

Recruitment is ongoing for that study, which began in October 2023. Autogene cevumeran will be combined with Genentech’s PD-L1 immune checkpoint inhibitor Tecentriq and chemotherapy compared with the standard-of-care chemotherapy.

Elsewhere, the cancer vaccine is being tested in three phase 2 tests in melanoma and as an add-on treatment for colorectal cancer.

BioNTech and Roche’s Genentech began working together in 2016 in a deal worth $310 million in upfront and near-term payments to use the German biotech’s cancer vaccine platform.

BioNTech is slightly behind chief competitor Moderna, which is working with Merck & Co. to develop the phase 3 cancer vaccine mRNA-4157 as an add-on treatment for high-risk melanoma. The companies also began pursuing earlier studies in lung cancer last year.