BioNTech Halts Phase 2 Trial of Individualized mRNA Cancer Vaccine Autogene Cevumeran in Colorectal Cancer

BioNTech announced it has terminated the Phase 2 BNT122-01 trial evaluating autogene cevumeran (BNT122/RO7198457) as an adjuvant monotherapy in patients with circulating tumor DNA (ctDNA)-positive, surgically resected Stage II (high risk) or Stage III colorectal cancer.¹ Autogene cevumeran is an individualized mRNA cancer immunotherapy jointly developed by BioNTech and Genentech, and the termination decision was made in consultation with Genentech.¹

Why was the trial terminated?

The decision follows a new recommendation from the trial's independent Data Safety Monitoring Board (DSMB).¹ The futility boundary had already been crossed in October 2025, at which point the DSMB concluded available data were not mature enough to support reliable efficacy conclusions and that follow-up time was insufficient to evaluate the primary endpoint; BioNTech continued the trial per protocol at that time, with no objection from the DSMB.¹ In its most recent review, the DSMB identified a numerical imbalance in overall survival between treatment arms in this specific patient population and determined that continuing the trial was unlikely to change the efficacy outcome, recommending discontinuation of patient treatment and termination of the trial.¹ BioNTech states no new safety signals were identified regarding autogene cevumeran, and the company has informed investigators and relevant regulatory authorities.¹

"Any decision concerning clinical trials is made with utmost care, keeping patients as our highest priority," said Özlem Türeci, MD, co-founder and chief medical officer at BioNTech. "While this outcome is not what we had envisioned for mRNA as a monotherapy in colorectal cancer, it provides scientific insight into the challenges of treating immunotherapy-insensitive tumor types with immune-suppressive microenvironments and will help inform the further development of investigational mRNA cancer immunotherapies. We remain committed to mRNA as a key pillar in our oncology strategy and our novel-novel combination approaches."¹

What was the trial designed to test, and why is colorectal cancer a difficult target?

BNT122-01 was designed to assess whether autogene cevumeran, given as monotherapy without a supportive checkpoint inhibitor, could help prevent disease recurrence in this high-risk population compared with watchful waiting, the current standard of care.¹ BioNTech describes colorectal cancer as a biologically complex, immunologically "cold" tumor type that is historically largely unresponsive to immunotherapy and carries a high risk of metastatic relapse.¹ This immune-cold profile is a recurring challenge across mRNA neoantigen cancer vaccine programs, which rely on stimulating a T-cell response against tumor-specific mutations identified from a patient's own resected tissue; BioPharm International has covered how autogene cevumeran performed in an earlier phase 1 pancreatic cancer trial, in which roughly half of treated patients developed vaccine-induced T cells that persisted up to two years — a study that combined the vaccine with checkpoint inhibition and chemotherapy, a different trial design than the colorectal cancer monotherapy approach that was just terminated.²

What happens to autogene cevumeran's other programs?

The termination is specific to the colorectal cancer monotherapy trial. A separate phase 2 trial, IMcode003, evaluating autogene cevumeran in combination with checkpoint inhibition and chemotherapy in adjuvant pancreatic ductal adenocarcinoma, is not affected and continues as planned.¹ BioNTech's broader mRNA oncology pipeline has also evaluated autogene cevumeran in muscle-invasive urothelial carcinoma, and the company's individualized and off-the-shelf mRNA cancer immunotherapy programs remain a stated pillar of its oncology strategy.³

What's next?

BioNTech says it will conduct a thorough analysis of the trial data to inform patient population selection and clinical development strategy for potential future investigational mRNA cancer immunotherapies, with results to be shared with the scientific and medical community at an appropriate time.¹

"We are deeply grateful to the patients, families, investigators and site teams whose participation has made this important research possible." — Özlem Türeci, MD, co-founder and chief medical officer, BioNTech¹

References

1. BioNTech provides update on Phase 2 clinical trial of autogene cevumeran in resected colorectal cancer. News release. BioNTech SE; August 28, 2026. Accessed August 28, 2026.
2. BioNTech and Roche publish personalized vaccine data. BioPharm International. Accessed August 28, 2026.
3. 6 key developments shaping mRNA therapeutics beyond COVID-19 vaccines. BioPharm International. Published June 11, 2026. Accessed August 28, 2026.