Repeat BCG vaccination
Academic (Massachusetts General Hospital / collaborators)
Repeated Bacillus Calmette-Guerin vaccination repurposed as immune/metabolic therapy for established T1D. Long-running phase 2 adult and pediatric trials are active; early open-label signals are intriguing but controversial and not yet practice-changing.
The scorecard
BCG is proposed to alter autoreactive immunity and metabolism, but established-T1D trials focus more on HbA1c/glucose than clear C-peptide preservation.[1]
The strongest reported signal is delayed but persistent HbA1c lowering in small long-term cohorts; randomized confirmation remains pending.[3]
BCG is an old vaccine with broad human experience, but repeated use as T1D immunotherapy still requires trial safety confirmation.[2]
Trials include established adult and pediatric T1D, broader than many new-onset-only immunotherapies, though still research-only.[2]
Phase 2 adult and pediatric trials are active, but no regulator-approved T1D indication and no broad consensus efficacy proof.[1]
The full picture
BCG is one of the stranger long-running T1D hypotheses: an old tuberculosis vaccine used repeatedly to reshape immune and metabolic function. The appeal is access and safety; the problem is evidence certainty. Small long-term reports suggested delayed HbA1c improvement, but the field still needs rigorous randomized readouts to know whether this is real, reproducible, and clinically meaningful.
Coming soon
ETA · Phase 2 adult and pediatric trials active; no approval timeline
Sources
- [1]Repeat BCG vaccinations for established type 1 diabetes (NCT02081326) · registry
- [2]Repeat BCG vaccinations for pediatric type 1 diabetes (NCT05180591) · registry
- [3]Long-term reduction in hyperglycemia in advanced type 1 diabetes after BCG vaccination · peer-reviewed · 2018-06-21