The first new tuberculosis vaccine in a century shows ~50% protection
Published · Researched 2026-09-22
What happened (dated facts)
The M72/AS01E tuberculosis vaccine candidate demonstrated approximately 50% protection against TB disease over three years of follow-up in its Phase 2b trial — the first meaningful efficacy signal for a new TB vaccine in a century (the only licensed TB vaccine, BCG, dates to 1921 and protects poorly against adult pulmonary TB). A global Phase 3 trial of M72/AS01E began in March 2024 and reached full enrollment of 20,000 participants in April 2025. The story here is the completed Phase 2b outcome, not hopes for Phase 3: half of the TB cases that would have occurred were prevented.
Why it is genuinely positive
Tuberculosis still kills over a million people a year and is the world's deadliest single infectious disease. A vaccine that halves disease risk in adults would be the biggest TB breakthrough in a hundred years — and the Phase 2b result is the first hard evidence that such a vaccine is possible.
Social pulse
Strong global-health press circulation (Gates MRI, TB press). Targeted Threads searches did not return direct posts about M72/AS01E in this session. The social layer here is global-health media rather than viral posts.
Verified quotes
None captured.
Verification
- Tier: 2
- Primary source: Gates Medical Research Institute announcement on the M72/AS01E program (https://www.gatesmri.org/gates-medical-research-institute-and-the-serum-institute-of-india-reach-agreement/). Proves: ~50% protection over 3 years in Phase 2b; Phase 3 launched March 2024, fully enrolled (20,000) April 2025.
- Social sources: health-press layer + targeted Threads searches (direct story posts not captured — noted honestly). Proves: sustained coverage and community relevance via health media.
- Positivity check: completed-trial efficacy outcome (~50% protection) for a disease with no effective adult vaccine — genuine advance; Phase 3 framed as ongoing, not as a result.
Key facts
| Fact | Value | Source | Date |
|---|---|---|---|
| Phase 2b efficacy | ~50% protection over 3 years | Gates MRI | — |
| Phase 3 start | March 2024 | Gates MRI | 2024-03 |
| Phase 3 enrollment | 20,000 participants, full enrollment April 2025 | Gates MRI | 2025-04 |
| Context | BCG (1921) is the only licensed TB vaccine; poor adult pulmonary protection | General knowledge, cited in coverage | — |
UNVERIFIED points
- Social-layer posts about M72/AS01E were not yet observed; tier cannot be finalized until they are.
- Precise Phase 2b publication details were not re-verified against the journal paper this session.
Sources
- Primary source: Gates Medical Research Institute announcement on the M72/AS01E program ( — retrieval date not recorded