Eight Phase 3 Trials, 29 Phase 2 Readouts, and a Diversifying Pipeline: Eyes on Alzheimer’s in 2026

Alzheimer’s research has entered a period of unprecedented clinical activity. Following the approvals of the first disease-modifying therapies, attention is shifting toward what comes next: new mechanisms, combination approaches, earlier intervention, and treatments designed for broader patient populations. With eight Phase 3 trials reaching key milestones and dozens of Phase 2 studies expected to report results in 2026, the field is generating more clinical evidence than at any point in its history. The outcome of these studies could shape the next generation of Alzheimer’s treatment strategies for years to come.

A Pipeline That Has Fundamentally Changed Shape

Ten years ago, Alzheimer’s drug development meant amyloid. One target, one hypothesis, serial failure.

The Alzheimer’s Association’s 2026 pipeline report, counts 192 active clinical trials evaluating 158 novel agents. Eight Phase 3 trials reach their primary completion date this year. Twenty-nine Phase 2 trials complete in 2026. That volume of readouts in a single calendar year is unprecedented for this field.

The shape of the pipeline has shifted just as dramatically as its size. Amyloid-targeting agents now make up 18% of all pipeline drugs — down from roughly 33% a decade ago. Tau-targeted agents and inflammation/immune therapies have each grown from around 6% to around 20% of the pipeline. Researchers now identify 17 distinct aspects of Alzheimer’s pathophysiology targeted by at least one drug in current trials. The field has moved from a single hypothesis to a genuine multi-mechanism model.

Here is what is actually running — and what to watch.

The Eight Phase 3 Trials Completing in 2026

The eight Phase 3 studies expected to reach major milestones in 2026 represent the most diverse late-stage Alzheimer’s pipeline ever assembled. Some aim to improve upon the modest benefits of current therapies, while others target entirely different populations—from asymptomatic individuals at risk of disease to patients with moderate or severe Alzheimer’s. The breadth of these programs illustrates a field increasingly willing to pursue multiple paths toward the same goal.

1. APOLLOE4 — Oral ALZ-801 (Valiltramiprosate) | NCT04770220

This is the most commercially significant oral drug candidate in the current Phase 3 pipeline. ALZ-801 (valiltramiprosate), developed by Alzheon, targets the formation of soluble amyloid oligomers — upstream of the plaques that lecanemab and donanemab clear — in a specific high-risk population: APOE4/4 homozygotes, who carry two copies of the highest-risk Alzheimer’s gene and represent approximately 15% of all patients.

Topline Phase 3 results were released in April 2025. The drug missed its primary endpoint in the full APOE4/4 population but showed significant efficacy in the MCI subgroup. Importantly, it carries no ARIA risk — the brain swelling complication that limits the anti-amyloid antibodies. An oral pill with no ARIA risk, in a genetically defined high-risk population, fills a gap that no approved therapy currently addresses. A long-term extension study (NCT06304883) continues. Regulatory filings are planned in the US, UK, and Canada.

2. LUCIDITY — HMTM (Hydromethylthionine Mesylate) | NCT03446001

TauRx’s HMTM is an oral tau aggregation inhibitor — the only late-stage tau therapeutic that functions as a small-molecule pill rather than a biologic infusion. The Phase 3 LUCIDITY trial enrolled 598 patients ranging from MCI to moderate Alzheimer’s. The trial faced a significant methodological complication: the placebo arm used a low dose of methylthioninium chloride that unexpectedly produced drug-level effects, preventing a clean placebo comparison on primary endpoints.

Despite that, two-year data showed sustained cognitive benefits over baseline and a significant reduction in neurofilament light chain (NfL) — an established biomarker of neurodegeneration. TauRx has submitted a UK Marketing Authorisation Application to the MHRA, under accelerated assessment, and has filed or plans to file in the US and other territories. If approved anywhere, HMTM would be the first oral disease-modifying Alzheimer’s therapy to reach patients.

3. EVOKE & EVOKE+ — Oral Semaglutide | NCT04777396 & NCT04777409

The most watched trials of 2025 were these two. Novo Nordisk’s oral semaglutide — the GLP-1 receptor agonist best known as Ozempic — was evaluated in 3,808 adults with early Alzheimer’s across 566 sites in 40 countries. The trials asked a specific question: does a drug that reduces neuroinflammation, improves insulin signaling, and reduces vascular risk factors also slow cognitive decline?

The Lancet published the full results in March 2026. Semaglutide did not meet its primary endpoint — it did not demonstrate superiority over placebo in slowing disease progression on the CDR-Sum of Boxes measure. It was well tolerated, and AD-related biomarkers did improve. The results close one chapter on GLP-1 in Alzheimer’s but open questions about which patient subgroups or earlier disease stages might show a different profile.

4. KarXT (Xanomeline-Trospium) — Alzheimer’s Psychosis | NCT05511363

This Phase 3 study (ADEPT-1, estimated primary completion October 2026) evaluates KarXT — now owned by Bristol-Myers Squibb after its 2024 Karuna acquisition — for relapse prevention in psychosis associated with Alzheimer’s disease. KarXT received FDA approval in September 2024 for schizophrenia under the brand name Cobenfy. This trial extends that approval hypothesis into the neuropsychiatric symptom (NPS) space of Alzheimer’s — agitation, hallucinations, and paranoia — where there is substantial unmet need and no currently approved agent in this mechanism class.

5. AHEAD 3-45 — Lecanemab in Preclinical Alzheimer’s | NCT04468659

This Eisai/Biogen and NIH-funded study tests lecanemab in cognitively normal individuals with intermediate or elevated amyloid — people who have the pathology but have not yet developed symptoms. It is the most consequential prevention trial currently running in the field. If lecanemab can slow or halt cognitive decline before symptoms appear, it rewrites the entire treatment paradigm from disease management to disease prevention. Primary completion is estimated for late 2028, with interim updates and emerging data expected to become available as the study progresses, ahead of final results being presented at AAIC or a subsequent congress.

6. GV1001 Phase 3 — Moderate to Severe Alzheimer’s | NCT05269394

GemVax & KAEL’s GV1001 is a peptide fragment of telomerase reverse transcriptase with anti-inflammatory, antioxidant, and neuroprotective properties. It was originally developed as a cancer vaccine. The Korean Phase 3 study enrolled 936 patients with moderate to severe Alzheimer’s — a population almost entirely excluded from the amyloid antibody trials — and is slated for completion in April 2026. Phase 2 data in this population showed improvements in cognition and daily function when added to donepezil. This trial is the highest-enrollment Alzheimer’s study targeting the moderate-to-severe stage currently running globally.

7. Metformin (MIDAS) — Metabolic Pathway | NCT04098666

Metformin — the world’s most widely used diabetes drug — has been repurposed as an Alzheimer’s candidate based on its effects on insulin signaling, mitochondrial function, and neuroinflammation. The MIDAS Phase 3 trial evaluates its effect on cognitive decline in patients with amnestic MCI or early Alzheimer’s. Metformin has a decades-long safety record and negligible cost, making it one of the few candidates that could reach global access immediately if it works. Primary completion is estimated for September 2026.

8. Wujia Yizhi — TCM Formulation | NCT05010603

A Chinese herbal formulation with a Phase 3 trial running through September 2026. The study targets late-onset Alzheimer’s. This trial reflects the broader diversification of the global pipeline — including traditional medicine frameworks — and is being conducted to rigorous randomized controlled design standards.

Phase 2 Trials to Watch in 2026

The Phase 3 studies may define near-term treatment options, but the Phase 2 pipeline offers a glimpse of the field’s longer-term direction. Many of the most closely watched mid-stage programs are testing approaches designed to address the limitations of current therapies, from reducing treatment burden and safety concerns to targeting biological pathways beyond amyloid. Several of these studies are expected to deliver important data in 2026.

• Sabirnetug (ACU-193) — Amyloid Oligomer Antibody | ALTITUDE-AD NCT06335173

Acumen Pharmaceuticals’ sabirnetug is the most closely watched antibody in the current Phase 2 cohort. Unlike lecanemab and donanemab, which target amyloid plaques and protofibrils broadly, sabirnetug selectively targets soluble amyloid beta oligomers (AβOs) — the earliest and most neurotoxic form of amyloid. Phase 1 data showed favorable safety, low ARIA rates, target engagement, and amyloid plaque reduction at the two highest doses. FDA Fast Track designation is granted. ALTITUDE-AD enrolled 542 participants and opened its open-label extension in November 2025. Topline results are expected in late 2026. If sabirnetug can slow decline with a lower ARIA burden than existing antibodies, it addresses the field’s most significant safety constraint.

• Diranersen (BIIB080) — Tau ASO | Phase 2 CELIA NCT05399888

Biogen’s diranersen delivered its Phase 2 CELIA topline results on May 14, 2026. The study missed its primary endpoint but showed both a reduction in tau pathology and a slowing of clinical decline — the first randomized Phase 2 evidence of clinical benefit from a tau-directed therapy. The Alzheimer’s Association confirmed Biogen will continue development, and full data will be presented at AAIC in July. FDA Fast Track designation is in place. This is the single most scientifically significant result of 2026 so far. It opens the door to combination amyloid-plus-tau therapy as a realistic near-term trial design.

• ACI-24.060 — Active Amyloid Vaccine (AC Immune / Takeda) | Phase 1b/2 ABATE NCT05462106

AC Immune and Takeda are advancing ACI-24.060, an active immunotherapy (vaccine) approach designed to stimulate the body’s own immune response against amyloid beta. The Phase 1b/2 ABATE study is evaluating the candidate in adults with Down syndrome, a population at particularly high risk of developing Alzheimer’s disease due to the overproduction of amyloid precursor protein. Unlike passive antibody therapies that require repeated infusions or injections, active vaccines aim to generate durable immune responses through periodic booster dosing. If successful, ACI-24.060 could offer a more scalable and potentially lower-burden approach to amyloid-targeted treatment and prevention.

• E2814 — Anti-Tau Antibody in Combination | Phase 2/3 NCT06602258

Eisai is evaluating E2814, an antibody targeting tau’s MTBR (microtubule-binding region), as a potential combination therapy with lecanemab. The rationale is direct: if lecanemab clears amyloid and E2814 suppresses tau propagation simultaneously, the combination may achieve cognitive benefits neither drug reaches alone. This is the most advanced combination trial in the field. Results from the combination arm will begin maturing in 2026–2027.

What the Diversity of the Pipeline Actually Means

The 2026 pipeline is not just bigger than 2016. It is structurally different.

Repurposed agents now account for 35% of all pipeline drugs — including metformin, semaglutide, and GV1001. Repurposed drugs already have safety data, which compresses development timelines. If any of them work, they could reach patients faster and at lower cost than a novel biologic.

The shift toward tau, inflammation, and metabolic targets reflects something equally important: the field accepts that amyloid alone will not be sufficient for all patients. The approved anti-amyloid drugs slow decline modestly in carefully selected early-stage patients. They do not stop it. They do not reverse it. They do not work in the moderate or severe stages. As pipeline report lead author Dr. Jeffrey Cummings noted: “Alzheimer’s is no longer an untreatable disease. It is now a disease with treatments that successfully interfere in the disease process.”

The next layer of that statement — treatments that interfere more substantially, in more patients, at more stages — is what the 2026 trials are built to answer.

AAIC in July 2026 will present full data from CELIA and likely several other 2026 Phase 2 completions. Together with the Phase 3 readouts already delivered or expected by year-end, this year represents the most concentrated burst of Alzheimer’s clinical evidence in the disease’s research history.

The pipeline is not a list of bets. It is a system — multiple mechanisms, multiple stages, multiple populations — designed so that enough survive to change the trajectory of a disease that currently affects more than 55 million people worldwide.

Author

Bernice Lottering

Related Post

Perspectives

Two Approved Drugs, Hundreds of Trials, and a New Target: Alzheimer’s at a Turning Point

2026-06-02

Ranking & Reports

Japan’s 2025 Bioindustry Awards: From Alzheimer’s Treatments to Regenerative Medicine, the Nation Charts Its Next Biotech Course

2025-10-16

Trials & Approvals

FDA Granted Eisai and Biogen’s New Alzheimer’s Drug a Traditional Approval, Making Medicare Coverage Possible

2023-07-11