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Every row

Showing 10 of 382 rows. One row per study per exposure: a study that tested two different things appears twice, once for each.

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Research and outcomes, 10 rows. Every row links to its source.
Exposure Question Direction Outcome measured Design People Effect size, as the source reported it Source
Omega-3 / fish and fish oil Diet and supplements Prevention Mixed
why

The biochemical primary outcome was met (DHA raised the CSF DHA-to-arachidonic-acid ratio versus placebo), but there was no difference in cognition or brain volume over 24 months. The authors recommend against further supplementation trials of this kind.

CSF DHA/AA ratio at 6 months (primary, target engagement); cognition and brain volumes at 24 months phase 2 trial 365 DHA supplementation increased CSF DHA/AA ratio at 6 months vs placebo (0.17 [95% CI 0.15-0.18] vs -0.02 [95% CI -0.04 to -0.0004]; difference 0.19 [95% CI 0.16-0.21]; p < 0.0001), independent of APOE ε4 status (interaction p = 0.71). Dropout was 38%, mainly due to COVID-19. No treatment differences were observed in brain volumes or cognitive performance over 24 months EBioMedicine 2026
✓ Peer-reviewed PMID 42315445
Anti-amyloid antibody Medicines Treatment Benefit
why

Phase Ib/IIa biomarker result in 13 people; no cognitive outcome measured.

Amyloid PET and CSF biomarkers (surrogate) phase 2 trial 13 3.6 mg/kg cohort: "-89 centiloids after 12 weeks (n=13), and -107 centiloids after 28 weeks (n=12)" on amyloid PET; at week 25 CSF "total tau, phosphorylated tau181, and neurogranin were reduced by 30%, 34%, and 29%, respectively" Alzheimer's & Dementia (AAIC 2025 conference abstract) 2025
⚠ Conference abstract — not peer-reviewed PMC12740797
Anti-tau therapy Medicines Treatment No effect
why

The primary endpoint was not met: the low dose showed no clinically meaningful benefit and the 3 mg dose showed 32% greater progression than placebo, with more serious adverse events. Less whole-brain volume loss on MRI is a surrogate finding.

iADRS disease-progression ratio at 100 weeks (primary); tau PET, brain volume, adverse events phase 2 trial 327 The disease progression ratio relative to placebo was 0.84 (95% credible interval [CrI], 0.66-1.04) for the ceperognastat 0.75 mg group and 1.32 (CrI, 1.10-1.58) for the ceperognastat 3 mg group, corresponding to 16% less and 32% greater progression, respectively. No benefits were demonstrated for secondary clinical end points JAMA 2026
✓ Peer-reviewed PMID 42441396
Anti-tau therapy Medicines Treatment No effect
why

The primary clinical endpoint (CDR-SB) was not met in the overall population. The tau figures are a biomarker outcome, not a clinical one.

CDR-SB (primary); tau PET accumulation phase 2 trial 466 "Slowed the rate of tau accumulation versus placebo in key brain regions by 33%-58%" overall and "by 63%-67%" in the low-tau or APOE4 non-carrier subgroup; "In the overall study population, no beneficial effect of low- or high-dose bepranemab compared with placebo was observed on the primary endpoint"; ADAS-Cog14 decline slowed 21-25% UCB press release (data presented at CTAD 2024) 2024
⚠ Press release — not a study no DOI or PMID exists
Anti-tau therapy Medicines Treatment No effect
why

ADAS-Cog11 showed slower decline, but the co-primary functional endpoint (ADCS-ADL) did not differ and the authors classify the study as negative.

ADCS-ADL and ADAS-Cog11 (co-primary) at week 49 phase 2 trial 272 "At week 49, the semorinemab arm demonstrated a 42.2% reduction (-2.89 points, 95% CI -4.56 to -1.21, p = 0.0008) in decline on the ADAS-Cog11 (coprimary endpoint) relative to the placebo arm"; ADCS-ADL difference -0.83 points (95% CI -3.39 to 1.72, p = 0.52), with no difference on MMSE or CDR-SB Neurology 2023
✓ Peer-reviewed PMID 37643887
Antiviral (valacyclovir) for HSV-seropositive Alzheimer's Medicines Treatment Harm
why

Direction is for valacyclovir: cognition worsened more on the drug than on placebo on the primary outcome (between-group difference 3.93 ADAS-Cog points, P = .01); function, amyloid PET and tau PET did not differ. The authors conclude it is not recommended.

ADAS-Cog change at 78 weeks (primary); ADCS-ADL, amyloid PET and tau PET phase 2 trial 120 At 78 weeks, the LSM change in the 11-item ADAS-Cognitive Subscale score was 10.86 (95% CI, 8.80 to 12.91) in the valacyclovir group vs 6.92 (95% CI, 4.88 to 8.97) in the placebo group, indicating greater cognitive worsening with valacyclovir than placebo (between-group difference, 3.93 [95% CI, 1.03 to 6.83]; P = .01). The LSM change in the ADCS-ADL Scale score at 78 weeks was -13.78 (95% CI, -17.00 to -10.56) in the valacyclovir group vs -10.16 (95% CI, -13.37 to -6.96) in the placebo group (between-group difference, -3.62 [95% CI, -8.16 to 0.93]) JAMA 2026
✓ Peer-reviewed PMID 41405855
GLP-1 receptor agonist Medicines Treatment No effect
why

Primary outcome null. One secondary cognitive measure (ADAS-Exec) favoured liraglutide on an unadjusted test; ADCS-ADL and CDR-SB did not.

Cerebral glucose metabolic rate at 52 weeks (primary) phase 2 trial 204 Cerebral glucose metabolism difference -0.17 (95% CI -0.39 to 0.06, p=0.14); CDR-SB -0.06 (95% CI -0.57 to 0.44) Nature Medicine 2026
✓ Peer-reviewed PMID 41326666
Other investigational drug Medicines Treatment No effect
why

The trial did not meet its primary endpoint at any of three doses despite sustained target engagement (lower CSF soluble TREM2, higher osteopontin); the most frequent adverse events were MRI changes resembling ARIA.

Change from baseline in CDR-SB at week 96 versus placebo (primary endpoint) with the TREM2 agonist antibody AL002 phase 2 trial 381 least squares mean difference versus placebo (95% confidence interval) at week 96: 15 mg kg-1 -0.31 (-1.61 to 0.98), 40 mg kg-1 0.13 (-1.18 to 1.43) and 60 mg kg-1 -0.17 (-1.49 to 1.15); P > 0.05 from mixed-effects model for repeated measures Nature Medicine 2026
✓ Peer-reviewed PMID 41787076
Psychotropics for agitation / psychosis Medicines Treatment Benefit
why

The NPI-C agitation/aggression measure did not reach significance (p=0.094).

Pittsburgh Agitation Scale over 3 weeks phase 2 trial 75 PAS decline difference -0.74/week (p=0.015, ES 0.53); NPI-C A/A -1.26/week (p=0.094, ES 0.36) The American Journal of Geriatric Psychiatry 2026
✓ Peer-reviewed PMID 41350162
Psychotropics for agitation / psychosis Medicines Treatment Benefit
why

The authors describe the reduction as small (-1.32 points).

NPI apathy score at 6 weeks phase 2 trial 94 NPI apathy change -1.32 points (95% CI -2.43 to -0.21) vs placebo The Lancet Neurology 2025
✓ Peer-reviewed PMID 39862881

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