FDA Approves At-Home Version of Leqembi (Lecanemab): What It Means for U.S. Patients and Caregivers

On August 29, 2025, the U.S. Food and Drug Administration approved a once-weekly, at-home, subcutaneous (under-the-skin) maintenance dose of the Alzheimer’s drug Leqembi (lecanemab), delivered via an autoinjector branded Leqembi IQLIK. This is the first Alzheimer’s therapy patients (or care partners) can administer at home after completing the initial infusion phase. ReutersEisai

TL;DR

• What changed: After the initial 18-month IV phase, eligible patients can switch to weekly at-home injections. Reuters

• Why it matters: Reduces travel, infusion-chair bottlenecks, and caregiver burden—potentially improving persistence with therapy. ReutersAlzheimer’s Association

• Evidence base: Phase 3 CLARITY-AD demonstrated ~27% slowing of clinical decline vs. placebo at 18 months; long-term data suggest benefits continue with ongoing treatment. New England Journal of MedicinePubMedAlzheimer’s Association

• Safety: Risk of ARIA (amyloid-related imaging abnormalities) remains; most events occur in first 6 months and decline over time with monitoring. New England Journal of MedicinePMCEisai

What exactly did the FDA approve?

The FDA authorized weekly subcutaneous maintenance dosing of lecanemab via a prefilled autoinjector for people who completed 18 months of biweekly IV infusions for early Alzheimer’s disease. Patients may continue monthly IV maintenance instead, but the autoinjector provides an at-home option designed to reduce treatment burden. Reuters

Pricing & launch: Eisai and Biogen say Leqembi IQLIK launches Oct. 6, 2025 in the U.S. The companies cite an annual list price of $19,500 for the 360 mg single-dose autoinjectors (before insurance). Medicare coverage rules for anti-amyloid therapies remain in effect. Reuters

The science behind Leqembi

Leqembi targets toxic amyloid-β protofibrils, helping clear amyloid plaques linked with cognitive decline in Alzheimer’s disease. In CLARITY-AD, an 18-month, double-blind, placebo-controlled Phase 3 trial, lecanemab slowed decline by ~27% on the CDR-SB scale (primary endpoint) and improved secondary measures of cognition and function. New England Journal of MedicinePubMed

Safety—ARIA: CLARITY-AD reported ARIA-E in ~12.6% and ARIA-H up to ~17% of treated participants, typically within the first six months; many cases were asymptomatic. Open-label extension data suggest ARIA rates drop after the first year with continued therapy. Clinicians monitor with MRI and adjust dosing as needed. New England Journal of MedicinePMCEisaiScience Media Centre

Why maintenance matters: Post-trial analyses and LTE/OLE data indicate benefits accrue with longer use, and that disease progression resumes if therapy stops after plaque clearance—supporting ongoing maintenance dosing. Alzheimer’s Association

What changes with an at-home autoinjector?

Access & convenience. The Alzheimer’s Association calls the decision “continued progress,” noting that self- or caregiver-administered weekly shots could be “less burdensome and easier” than IV infusions, which require travel and chair time. Alzheimer’s Association

Health-system impact. Eisai’s chief clinical officer told Reuters that home injections could free up infusion chairs for new starts, potentially improving overall access. Reuters

PK/PD rationale. Data supporting the SC autoinjector show drug exposure comparable to IV (within bioequivalence ranges), enabling a weekly 360 mg dose to maintain target levels following the initial IV phase. Neurology live

Who is eligible?

• Diagnosis: Mild cognitive impairment or mild dementia due to Alzheimer’s, with amyloid positivity confirmed (PET or CSF). BrightFocus Foundation

• Treatment sequence: Patients complete the 18-month IV initiation phase before switching to the weekly autoinjector for maintenance (or monthly IV). ReutersBrightFocus Foundation

• Monitoring: Ongoing MRI surveillance for ARIA per labeling and clinical judgment. New England Journal of Medicine

Expert quotes

• Maria C. Carrillo, PhD, Chief Science Officer, Alzheimer’s Association:
  “We are seeing the evolution of amyloid targeting antibody treatments, including improvements in drug delivery and acknowledgment that this class of treatments continues to demonstrate clinical benefit beyond the 18-month clinical trial data.” Alzheimer’s Association

• Howard Fillit, MD, Co-founder & CSO, Alzheimer’s Drug Discovery Foundation:
  Subcutaneous maintenance dosing is a “crucial step toward making Leqembi more accessible… similar to how diabetes and GLP-1 medications are delivered,” paving the way toward more convenient regimens. Alzheimer's Drug Discovery Foundation

• Lynn Kramer, MD, Chief Clinical Officer, Eisai (to Reuters):
  At-home injections “may open up more infusion chairs” and expand initiation capacity for patients. Reuters

Patient & caregiver implications (real-world perspective)

• Less travel, more flexibility: Weekly home dosing eliminates twice-monthly infusion visits, attractive for rural patients or those with mobility limits. ReutersBrightFocus Foundation

• Caregiver workload: The Association expects simpler routines and higher adherence, potentially translating into more sustained benefits. Alzheimer’s Association

• Costs & coverage: List pricing is public; actual out-of-pocket depends on Medicare/commercial coverage and support programs. ReutersBrightFocus Foundation

What’s still to watch

1. Use earlier in care: The newly approved autoinjector is for maintenance after IV; Eisai aims to evaluate SC initiation regimens (e.g., 500 mg under study). Regulators will review additional data. EisaiPR Newswire

2. Long-term outcomes: Ongoing LTE and ALZ-NET real-world data will clarify durability, safety, and health-economic impact. Alzheimer’s Association

3. Comparative landscape: Kisunla (donanemab) offers monthly IV maintenance; how at-home SC changes market adoption, adherence, and equity will be key. Reuters

Clinical evidence snapshot

• Efficacy: ~27% slowing on CDR-SB at 18 months (NEJM). New England Journal of Medicine

• Safety: ARIA-E ~12.6% (mostly early; often asymptomatic), ARIA-H up to ~17%; careful MRI monitoring required. New England Journal of MedicinePMCScience Media Centre

• SC vs IV exposure: Comparable exposure supports weekly 360 mg maintenance dose via autoinjector. Neurology live

Bottom line

The FDA’s nod to at-home Leqembi injections is a practical leap: same mechanism and evidence base, less friction for patients and care partners. The convenience could boost treatment persistence and access, provided safety monitoring and coverage logistics remain robust. ReutersAlzheimer’s Association

Sources

Reuters; Alzheimer’s Association; Eisai/Biogen press and investor materials; BrightFocus Foundation; NEJM CLARITY-AD; NeurologyLive and peer-reviewed summaries. Key links embedded above. ReutersAlzheimer’s AssociationEisaiBiogen InvestorsBrightFocus FoundationNew England Journal of MedicinePubMedNeurology live