What are the most effective FDA-approved Alzheimer's drugs currently?

1. Disease‑modifying antibodies that changed the treatment landscape

The most consequential recent approvals are anti‑amyloid immunotherapies. The FDA converted lecanemab (Leqembi) to traditional approval after a confirmatory Phase 3 trial verified clinical benefit and the drug is now indicated for early Alzheimer’s disease, marking “the first verification that a drug targeting the underlying disease process…has shown clinical benefit” ^[1]. Eli Lilly’s donanemab (marketed as Kisunla/Kisulna) is also FDA‑approved for early symptomatic Alzheimer’s — its label and dosing have been updated to reduce ARIA (amyloid‑related imaging abnormalities) risk while preserving amyloid‑clearing effects ^{[2] [5]}.

2. What “most effective” means in practice

Effectiveness here is narrow: these antibodies reduce brain amyloid and produced statistically significant, modest slowing of cognitive and functional decline in early‑stage patients in pivotal trials, not cure or reversal ^{[1] [6]}. The clinical impact is described in the literature and regulatory statements as modest but statistically significant; experts quoted in reporting call the approvals a major step forward that catalyzes further development ^{[3] [1]}.

3. Who benefits and who doesn’t

Both lecanemab and donanemab are indicated for early Alzheimer’s disease—people with mild cognitive impairment or mild dementia with confirmed amyloid pathology—meaning they are not broadly applicable to later stages without demonstrated benefit in that population ^{[6] [2]}. The NIH and academic reviews emphasize ongoing work to define optimal use in different stages and populations and to evaluate combinations or earlier preventive strategies ^{[7] [6]}.

4. Safety and practical trade‑offs

These therapies carry risks, notably ARIA (brain swelling or bleeding seen on MRI). Donanemab’s label update and titration recommendation specifically aim to lower ARIA‑E risk while maintaining efficacy, underscoring safety trade‑offs and the need for careful monitoring ^[5]. Regulatory materials for lecanemab stress confirmatory trial data and post‑marketing requirements tied to real‑world safety and benefit ^{[1] [8]}.

5. Symptom‑management drugs still matter

For most patients and stages, traditional symptomatic treatments remain central: cholinesterase inhibitors and memantine continue as standard care, with innovations in delivery (for example, a once‑weekly donepezil transdermal patch approved in 2022) and newer agents like benzgalantamine (Zunveyl) reported by company sources to have gained FDA approval for mild‑to‑moderate disease ^{[3] [4]}. These therapies do not remove amyloid but improve cognition or function short‑term for many patients ^{[3] [9]}.

6. Cost, access and implementation issues

Industry and regulatory announcements note efforts to broaden access and to develop less burdensome delivery (a subcutaneous lecanemab autoinjector under review with a PDUFA date) and to enable stopping rules for donanemab when amyloid is cleared—measures with implications for cost and logistics but also potential commercial framing from manufacturers ^{[10] [2]}. The NIH signals continued investment to study how best to use these agents across settings ^[7].

7. The near‑term pipeline and why that matters

Although two anti‑amyloid antibodies are now approved, the research landscape is broad: reviews of the 2025 pipeline identify 182 trials of 138 drugs, with many approaches targeting inflammation, tau, vascular health or synaptic resilience—meaning additional, possibly more effective or safer options could emerge ^{[11] [6]}. Industry statements and nonprofit experts frame current approvals as a catalyst for further investment ^{[3] [11]}.

Limitations: this summary relies on the supplied reporting and regulatory statements; available sources do not include head‑to‑head effectiveness data beyond trial reports nor detailed real‑world comparative outcomes across all stages (not found in current reporting).