Waiting for Lecanemab, a Family Learns to Count the Months

Introduction: a syringe, a conference, a family that hopes

A rendezvous in London that changes everything

From July 12 to 15, 2026, the city of London hosts the AAIC, the international conference of the Alzheimer's Association, one of the largest scientific gatherings on Alzheimer's disease anywhere on the planet (Alzheimer's Association). This year, attention centers on a drug that has become familiar in specialist circles: lecanemab, sold under the name Leqembi, developed by Eisai and Biogen. London is not unveiling a new molecule. It is unveiling data gathered after years of real-world use, far from controlled clinical trials, in actual practices, with actual families.

I have followed this file for a while, without ever having had a relative treated directly with this drug. I say that up front: I am not telling a story lived from the inside here, but the larger one of thousands of North American families who, since the FDA approved lecanemab in July 2023, have been learning to live with measured hope (Eisai Newsroom).

The weight of a diagnosis that shows no mercy

Alzheimer's disease remains, for now, a one-way trajectory. What lecanemab promises is not a cure, but a slowing of cognitive decline in people at an early stage, those who still have mild cognitive impairment or mild dementia. That is an essential nuance, and I repeat it gladly, because too many miracle promises have already let down entire families in this field.

The LEADER study, three years after approval

Half a thousand patients tracked in real life

The heart of the AAIC 2026 announcements rests on the LEADER study, an acronym for a multicenter retrospective study in real-world conditions, conducted across various American clinical sites, three years after lecanemab reached the market (PR Newswire). This study does not settle for measuring efficacy in a lab. It documents how the drug behaves once it leaves the cocoon of clinical trials and enters the imperfect daily grind of neighborhood clinics.

The headline session, scheduled for late afternoon on Tuesday, July 14 in London, is set to present results on the intravenous maintenance dosing every four weeks and, notably, the first reported data on at-home subcutaneous administration (PR Newswire). That is a concrete shift: moving from an in-clinic infusion to an injection that the patient, or their caregiver, can give at home.

What this changes for caregivers

For a family that has to arrange regular trips to an infusion center, often while juggling work, other children, and accumulated fatigue, the idea of an at-home injection is not a technical footnote. It is a breath of fresh air. A human-factors study has in fact shown that the majority of health professionals, caregivers, and patients successfully administered a full dose using the auto-injector developed for this purpose (Alzheimer's & Dementia, PMC).

The shift to the subcutaneous route

A weekly injection instead of a biweekly infusion

Lecanemab was originally administered intravenously every two weeks for eighteen months, before switching to maintenance every four weeks. In August 2025, the FDA approved a subcutaneous version, Leqembi IQLIK, for a weekly maintenance dose of 500 mg (Eisai Newsroom). A supplemental application to use this same formulation as a starting dose is currently under priority review at the FDA, with an action date set for August 24, 2026 (Business Insider).

The data show that a weekly 500 mg subcutaneous dose would achieve exposure equivalent to the biweekly intravenous infusion, with similar clinical and biomarker benefits (Eisai Newsroom). The safety profile is reported to remain comparable, with less than two percent incidence of injection or infusion-related reactions.

The concrete fallout for clinical practice

A session developed specifically for the AAIC, scheduled right at the opening on Sunday, July 12, is set to detail the emerging clinical evidence and practical considerations around this subcutaneous formulation, including the safety profile and real patient experience (Business Insider). This emphasis on lived reality, not just efficacy figures, reflects a growing awareness across the field: an effective treatment that is complicated to administer eventually gets abandoned by exhausted families.

The risks we must never downplay

The specter of ARIA

Lecanemab is not without danger. Amyloid-related imaging abnormalities, or ARIA, remain the most closely watched side effect. A study published in January 2026 on the first seventy patients treated at the University of Utah recorded fourteen cases of ARIA, or twenty percent, a rate judged consistent with earlier clinical trials, with no symptomatic cases (PubMed). The most significant association concerned the apolipoprotein E epsilon 4 genotype, not the distance between the patient's home and the clinic.

The manufacturer itself acknowledges, in the labeling approved by the FDA, that intracerebral hemorrhages larger than one centimeter in diameter have occurred in treated patients (FDA). That is not a detail to sweep under the rug. Any accessible discussion of this drug must include this clinical reality.

A caution that must remain the norm

It would be dishonest to present lecanemab as a miracle cure. The slowing of cognitive decline measured on the CDR-SB scale in the pivotal Clarity AD trial was 0.45 points at eighteen months, a statistically significant reduction but a modest one in absolute terms (FDA). Over three years, the cumulative reduction reportedly reaches 1.01 points compared with the ADNI reference cohort, and up to 1.75 points after four years of treatment (Eisai Newsroom).

Treatment persistence in the real world

Most patients continue beyond eighteen months

An analysis presented in March 2026 at the AD/PD conference in Copenhagen examined treatment persistence among more than ten thousand people who received at least one intravenous dose of lecanemab between January 2023 and November 2025, drawn from the PurpleLab CLEAR Claimshealth insurance database (Eisai Newsroom). Result: 78.4 percent of patients were still on treatment at eighteen months, 71.7 percent at twenty months, and 67.3 percent at twenty-four months.

These figures matter, because a chronic treatment only has value if patients actually stay on it over time. A miracle syringe that gets abandoned after six months serves no one.

An encouraging signal, but an incomplete one

It should be noted that this analysis covers a limited subset of 371 patients who started treatment in 2023 with twenty months of continuous follow-up, which remains a modest statistical base compared with the scale of Alzheimer's disease worldwide (Eisai Newsroom). The full LEADER data, expected in London, should broaden this picture.

Differences by patient sex

A session built specifically around this question

Among the upcoming presentations, a session developed for July 13 at eight in the morning is set to focus specifically on lecanemab outcomes by sex within the LEADER study (PR Newswire). This is a line of inquiry still rarely explored in the field of anti-amyloid therapies, and it could reveal differences in tolerance or efficacy between men and women.

Historically, pharmaceutical research has often overlooked variations tied to biological sex in its clinical trials. That the AAIC is devoting an entire session to this question, specifically for lecanemab, deserves to be noted.

Why this nuance matters for families

If significant differences emerge, this could influence dosing or monitoring decisions for millions of women living with Alzheimer's, a disease that statistically affects women more than men, partly because of their longer life expectancy.

The broader context of the anti-amyloid race

Donanemab, a competitor also making progress

Lecanemab is not alone in this field. Donanemab, developed by a rival company, has shown a benefit that keeps growing over three years compared with the ADNI cohort, with a group that started treatment early showing a twenty-seven percent reduction in the risk of progression to the next stage of the disease, compared with a group that started later (AAIC briefing document, January 2026). This competition between anti-amyloid approaches is pushing the whole field to accumulate real-world evidence.

Other therapeutic approaches, such as diranersen, which targets tau protein rather than amyloid, will also be presented at AAIC 2026 by Biogen, with phase 2 data from the CELIA study (Business Insider).

An industry multiplying its angles of attack

This diversity of approaches, targeting amyloid at times, tau protein at others, and lipid biomarkers as shown by a separate company presenting in London data on lipid transport proteins in cerebrospinal fluid (LinkedIn, Cognito Therapeutics), reflects a maturing research field. No one is betting on a single biological target anymore.

The question of cost and access

A treatment that remains costly and demanding

Despite advances in at-home administration, lecanemab remains a treatment that is heavy on logistics and finances. It requires regular brain imaging follow-up to monitor for ARIA, genotyping of apolipoprotein E in many protocols, and sustained medical oversight. For an average North American family, access to this kind of therapy depends heavily on insurance coverage and proximity to a specialized center.

The ALZ-NET network, created by the Alzheimer's Association to track patients receiving newly FDA-approved treatments, plays a central role in collecting this long-term safety data (Alzheimer's Association). Without this kind of infrastructure, the gap between clinical trial promises and on-the-ground reality would remain invisible.

Geographic equity, an issue too often forgotten

The study on the seventy Utah patients pointed out precisely that using distributed infusion sites increased access to treatment without significantly raising the risk, even across a widely spread-out region (PubMed). That is an encouraging point for patients living far from major urban centers.

What patients themselves are reporting

Reported satisfaction in earlier studies

At AAIC 2025, dozens of abstracts showed that the real-world experience of lecanemab and donanemab produced safety comparable to or better than in the large controlled clinical trials, and that patients reported being satisfied with the results (Alzheimer's & Dementia, PMC). This patient-reported satisfaction is an indicator that cannot be captured by brain scans or cognitive scores alone.

The ALZ-NET registry's safety-monitoring session, scheduled all day on July 13 at AAIC 2026, is set to dig deeper into this dimension with new real-world surveillance data (Business Insider).

The importance of lived experience, beyond statistics

A patient who lives with dignity a few extra months in a state of relative lucidity represents a victory that sometimes escapes researchers' spreadsheets. This human dimension is, to my mind, what justifies continuing to follow this file with attention, yielding neither to total cynicism nor to euphoria.

The persistent limits of current research

Results still preliminary on several fronts

As of this writing, several of the flagship AAIC 2026 presentations, notably the one on LEADER's at-home subcutaneous administration, have not yet taken place. The abstract identifiers for some sessions are still marked as to be determined in official releases (PR Newswire). It would be premature to draw definitive conclusions before the full data is actually presented, scheduled between July 12 and 15.

This methodological caution is not journalistic timidity. It is the only honest attitude toward data that, for now, exists mainly in the form of press releases from companies with a direct commercial interest in the product's success.

The gap between a press release and a scientific publication

A press release is not a peer-reviewed scientific paper. That difference matters enormously in a field whose recent history is full of promising announcements that deflated once put through the rigorous scrutiny of the scientific community.

The role of independent oversight bodies

The ALZ-NET registry as a safeguard

The strength of the American system rests partly on the existence of structures like ALZ-NET, funded by the Alzheimer's Association, which collect clinical and safety data independently of the manufacturers' direct commercial interests (Alzheimer's Association). This kind of infrastructure is what will eventually allow us to separate lecanemab's real effects from its marketing.

The FDA also requires, through the product's labeling, that clinicians be encouraged to participate in this registry, a mechanism that is a reminder the American agency has not entirely delegated post-market surveillance to companies' goodwill (Alzheimer's Association).

What this means for public trust

In a context where distrust of the pharmaceutical industry remains high, particularly in North America, the existence of independent oversight mechanisms is a serious argument in favor of these treatments' growing credibility, provided they keep existing and publishing their results without filters.

The West facing a global scientific race

Research largely driven from the United States and Europe

It is worth noting: the bulk of this cutting-edge research into anti-amyloid therapies is driven by American, Japanese, and European institutions, with clinical trials conducted notably in the United States, in Sweden, and elsewhere across the Western and allied world (PMC, Alzheimer's & Dementia). This is a concrete demonstration that the Western biomedical research ecosystem, despite its very real bureaucratic flaws, keeps producing measurable advances against some of the most devastating diseases of aging.

This scientific leadership is not a given forever. It depends on steady funding for basic research, on rigorous regulation like the FDA's, and on international collaboration that geopolitical tensions could one day undermine.

Why this deserves to be defended

Facing rival powers that invest massively in biotechnology without always respecting the same ethical standards for patient protection, the Western model of pharmaceutical development, with its slowness and its rigorous trials, retains a value too often underestimated in public debate.

The psychological dimension of early diagnosis

Knowing early, a double-edged burden

Because lecanemab is only effective at the early stage of the disease, its existence changes the calculus of diagnosis itself. North American families who once deliberately delayed a full cognitive evaluation for fear of an irreversible verdict now have a concrete reason to consult a neurologist or a memory clinic early. This behavioral shift, still hard to quantify precisely, could reshape screening habits in the medium term across several Western health systems.

But receiving an early diagnosis is not a neutral gift. It means living longer with knowledge of one's own trajectory, a psychological weight that mental health professionals are only beginning to document systematically in the specific context of anti-amyloid therapies.

The growing role of blood biomarkers

A briefing document presented ahead of AAIC 2026 already recommended the use of high-sensitivity blood tests as a triage tool in the Alzheimer's diagnostic pathway, a less invasive approach than a traditional lumbar puncture or amyloid PET imaging (AAIC briefing document, January 2026). This technical shift could democratize access to early screening, an almost mandatory condition for later benefiting from a treatment like lecanemab.

Toward London, with caution and curiosity

What I personally expect from this conference

I do not claim to know in advance exactly what the July 12 to 15 presentations in London will reveal. I only know that the LEADER study, with its sample of patients tracked in real-world conditions over three years, represents one of the strongest sources of information available to date on lecanemab outside the lab.

Families living with an early Alzheimer's diagnosis in their circle do not need inflamed promises. They need reliable data, honest professionals, and equitable access to treatments that actually exist.

A story still being written

This narrative has no heroic conclusion to offer, because medical reality does not yet provide one. What can be said, with the caution that is required, is that the file is moving forward, slowly, with scientific safeguards that deserve to be praised without being idealized.

Conclusion: between the lines of the press releases, a human reality

What this week in London will be remembered for

By the end of the AAIC 2026 conference, on July 15, the scientific community will likely have more concrete evidence on how lecanemab actually behaves, far from controlled trials, in medical practices across North America and elsewhere. At-home subcutaneous administration, if the results confirm expectations, could considerably ease the logistical burden on thousands of families.

But none of this will change the fundamental nature of the challenge: Alzheimer's disease remains incurable, and lecanemab, in the best-case scenario, slows a trajectory it does not reverse. That is little, compared with the dream of a cure. It is a great deal, compared with the total absence of options that prevailed barely a decade ago.

A hope that must be carried with both feet on the ground

I end this narrative as I began it: without having personally lived through this ordeal with a relative treated with lecanemab, but with the respect owed to those who, every week, travel to a clinic or, perhaps soon, open a box of syringes at home, to gain a few more months of clarity of mind.

By Maxime Marquette, columnist

Columnist's transparency note

Who I am and my acknowledged biases

I sign my columns under the name Maxime Marquette. I am neither a physician nor a neurology researcher: my role is to make scientific and industry data accessible, to provide context, and sometimes to question it, for readers who do not necessarily have time to read pharmaceutical press releases in full. I carry an acknowledged bias in favor of Western scientific rigor, while remaining critical of the commercial interests that inevitably accompany announcements of new treatments.

I have no personal connection to a relative treated with lecanemab, and I never claim otherwise in my writing.

What I do not yet know

I do not know, as of this writing, the precise content of the data being presented in London between July 12 and 15, 2026, since several presentations have not yet taken place. My method is to cross-check official laboratory press releases against already peer-reviewed scientific publications, available on platforms like PubMed, in order to avoid blindly reproducing promotional talking points.

Sources

Primary sources

Alzheimer's Association, official AAIC 2026 conference page — accessed July 4, 2026

Eisai Newsroom, release on data presented at AAIC 2026 — June 30, 2026

FDA, official labeling for Leqembi (lecanemab) — 2026

Secondary sources

PR Newswire, details on the LEADER and lecanemab sessions at AAIC 2026 — June 30, 2026

Business Insider, Biogen's full program for AAIC 2026 — June 29, 2026

PubMed, study on real-world lecanemab experience in the Intermountain West — January 18, 2026

Alzheimer's & Dementia (PMC), analysis on subcutaneous lecanemab and its potential benefits — December 25, 2025