Alzheimer's Disease International published the World Alzheimer Report 2026 in September 2026. The theme is the new era of dementia clinical trials; it draws on interviews with more than 45 key figures in the field and maps 158 candidate drugs in development and 192 trials.
The starkest set of numbers: roughly 55,000 participant slots worldwide. At the current screening failure rate of at least 70%, filling them would require screening about 350,000 people. In England, 551 people entered late-stage dementia trials over the past five years, against 24,000 in cancer trials over the same period.
Where the sites are: as of 1 January 2026 there were 3,156 AD trial sites in North America and 3,607 outside it (1,363 in Western Europe and Israel, 661 in Eastern Europe and Russia, 571 in Asia). Western Europe takes part in more than 70% of current global AD trials.
Who is in them: about 90% of participants in US AD biomarker research are non-Hispanic White. The HABS cohort (4,500+) found that the ATN framework behaves broadly as expected in non-Hispanic White participants, but that the sequence does not hold in Hispanic and African American participants — sample composition is not only a fairness issue, it decides whether the conclusions travel.
An honest conversion of the effect size: a 2025 study from Washington University in St. Louis converted slowing on CDR-SB into time of independent living; in very mild AD, lecanemab buys roughly 10 months without full-time care. The report's own phrasing is "from a steep slope to a gentler one" — not 24 months of complete stability.
The China section: an estimated 16 million people currently live with dementia, projected to exceed 45 million by 2050; regulators require at least 10% of participants in global phase 3 trials to come from China, otherwise a separate China trial is required.
What I want to discuss: blood-based pre-screening is the tool the report sees as most likely to change the picture — where you once had to screen 3,000 people to find 150, you can now start with a blood test. So where do AD trial participants actually come from in China: memory clinics, community screening, or family communities? Who has made this work, and which step is the one that jams?
The report is an advocacy document, not a systematic review: the search and screening process is not transparent, and the figures are not fully consistent across chapters — worth keeping in mind when citing it.