Vaccine Maker Halts Trial on mRNA Cancer Shot

BioNTech is terminating a phase 2 clinical trial of an experimental mRNA cancer vaccine in partnership with Genentech. The trial was halted on the recommendation of a monitoring board due to a numerical imbalance in overall survival between treatment groups. While signs of failure were noted in October 2025, the trial continued as data were not mature enough to draw reliable conclusions on efficacy.

• BioNTech is terminating a clinical trial for an experimental mRNA cancer vaccine.
• The trial was a phase 2 study testing the vaccine in patients with colorectal cancer.
• Genentech is a partner in the development of the vaccine.
• A monitoring board recommended halting the trial due to survival imbalances.
• The trial continued past October 2025 because efficacy data were not yet mature or reliable.
• The primary endpoint could not be evaluated due to insufficient follow-up time.