BioNTech's cancer vaccine misses key trial goal

BioNTech built its name on an mRNA vaccine that helped end the COVID pandemic. Beating cancer with the same technology is proving much harder. The company said Tuesday its experimental shot, BNT113, failed to slow tumor growth better than Merck's cancer drug Keytruda alone. The trial included 358 patients with HPV-linked head-and-neck cancer. That's BioNTech's third mRNA cancer setback this year.

BioNTech made its name teaching the immune system to attack a virus. Cancer is a harder target. Tumors can hide from the immune system in ways a virus can't. This trial is the latest sign that lesson is holding true. BioNTech says the study isn't over. It's still tracking whether patients live longer overall, the trial's second goal.

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Will the survival data save BNT113? Progression-free survival and overall survival don't always move together. Patients can live just as long even if their tumors grow sooner than hoped. BioNTech is holding out for that outcome. Investors will be watching those results closely before writing off the vaccine for good.