Injectable Alzheimer’s Drugs: A Promising Step Toward Accessible Treatment

The Alzheimer’s treatment landscape is undergoing a transformative shift with the recent approvals of Leqembi (lecanemab) and Kisunla (donanemab), offering patients hope for slowing the progression of this devastating disease. For the first time, these drugs provide an opportunity to retain cognitive function longer, granting patients and their families precious time to navigate the challenges of Alzheimer’s.  

While these innovations represent a major breakthrough, accessing such treatments remains challenging. Both Leqembi and Kisunla are currently administered via intravenous (IV) infusions, requiring patients to visit specialty health centers once or twice a month. This logistical burden can pose significant difficulty for those in remote areas or with limited mobility.  

However, this may soon change. Eisai, the manufacturer of Leqembi, has submitted an application to the Food and Drug Administration (FDA) for approval of a subcutaneous injectable version of the drug—an under-the-skin shot that could be self-administered at home. Similarly, Eli Lilly is advancing clinical trials for a new drug that may also be delivered via injection.  

Irina Skylar-Scott, MD, a neurologist and clinical assistant professor at Stanford University, called the move “a game changer,” emphasizing how subcutaneous anti-amyloid therapies could free patients and their families from time-consuming trips to infusion centers.  

A Game-Changing Injectable Leqembi  

Eisai’s efforts to convert Leqembi into a subcutaneous injection have shown promising results. Clinical trials revealed that the injectable form delivers greater amyloid plaque clearance and fewer systemic side effects than IV infusions. The FDA recently accepted Eisai’s application for the injectable version, with a decision anticipated by September 2025.  

If approved, the injectable formulation would be packaged in an autoinjector device, enabling patients to self-administer the drug in approximately 15 seconds. Initially, patients would still need to begin treatment with biweekly IV infusions before transitioning to weekly injections, though Eisai is finalizing details with the FDA regarding the duration of the IV initiation phase.  

“This development is monumental,” said Andrew Budson, MD, chief of Cognitive & Behavioral Neurology at the Veterans Affairs Boston Healthcare System. Budson said that many patients currently travel considerable distances to receive care, a barrier that self-administered injections could overcome.  

“For patients living in rural areas or those with demanding schedules, every hospital visit requires substantial coordination,” he said. “Providing a self-injection option would relieve families of significant logistical and emotional strain.”  

Eli Lilly Forges Ahead With a New Injectable Therapy  

Eli Lilly is conducting phase 3 trials on remternetug, a monoclonal antibody capable of clearing amyloid plaques more effectively than its predecessor, Kisunla. The drug is being tested in both subcutaneous injection and IV infusion forms.  

In addition, researchers at Washington University’s School of Medicine are studying remternetug’s potential in people with dominantly inherited Alzheimer’s disease (DIAD)—a rare genetic condition that causes early-onset Alzheimer’s symptoms as young as age 30. This trial involves participants as young as 19 years old and will evaluate whether quarterly injections can prevent or slow plaque development and ultimately halt the progression of the disease before symptoms arise.  

Balancing Accessibility With Monitoring  

While injectable versions of these drugs promise greater convenience, safety monitoring remains critical. Patients taking drugs like Leqembi or Kisunla require quarterly MRI scans to check for amyloid-related imaging abnormalities (ARIA), side effects that can include brain swelling or bleeding.  

Clinical trials indicate injection-related reactions occur less frequently than infusion-related ones, though there is a slight increase in ARIA cases among the injection group. Eisai noted that additional research is needed to confirm the comparability of safety outcomes between the injectable and IV forms.  

Medical experts stress that while self-administered injections could drastically reduce routine hospital visits, patients will still need periodic MRIs and healthcare consultations to monitor their progress.  

Andrew Budson emphasized how such changes will significantly ease caregiving burdens. “If patients can eliminate routine infusion visits with self-injections, they will only travel to the hospital for monitoring, saving time and energy.”  

The development of injectable Alzheimer’s drugs marks a pivotal step in reducing barriers to treatment, offering patients not only extended cognitive life but also greater flexibility in managing their care. As advancements continue, these innovations promise to reshape how—and where—patients access lifesaving therapies.