Following this month's FDA approval of Eli Lilly’s amyloid-busting antibody Kisunla (donanemab), the Alzheimer’s disease market is set to grow in earnest—and Lilly is already eyeing a spot at the top.
The green light—which cleared Kisunla to treat adults with early symptomatic Alzheimer’s disease (AD)—marks the culmination of more than 30 years of work in the disease field by Eli Lilly. Those efforts also required concurrent development of non-therapeutic resources like diagnostics to detect amyloid plaque in the brain, Dawn Brooks, global development leader for Alzheimer’s disease at Eli Lilly, said in a recent interview.
As with Eisai and Biogen’s AD antibody counterpart Leqembi (lecanemab), Kisunla's FDA-approved label requires the confirmation of amyloid beta pathology in patients’ brain tissue before they begin treatment.
On the back of Eisai and biogen’s full approval for Leqembi last year, Kisunla now provides a second option for patients in the early stages of AD. The arrival of a second approved therapy likely marks the “end of the beginning in treating this disease,” Andrew Lechleiter, VP of U.S. Alzheimer’s disease marketing at Lilly, added during the interview.
Pre-approval preparations
Prior to Kisunla’s FDA nod, Lilly was focused on laying the groundwork for the burgeoning Alzheimer’s disease treatment scene, primarily through the development of diagnostics, as well as raising awareness around the fact that “amyloid is the bad guy” affecting patients’ memory and thinking, Lechleiter said.
The company has been working to educate healthcare providers and imaging sites on how to use amyloid PET scans and other biomarker tests to diagnose AD, he added.
“From a consumer standpoint, we need to drive a sense of urgency,” Lechleiter said. Lilly will aim to accomplish that goal through disease state education and other campaigns with physicians, he explained.
As for Kisunla’s inevitable market square-off with Eisai and Biogen’s Leqembi, “a rising tide raises all boats,” Lechleiter said. Still, Lilly’s primary ambition isn’t just to compete, but to build out a modern Alzheimer’s disease treatment landscape and then “lead the market,” Lechleiter said.
Despite Leqembi’s full FDA approval last summer, there is still a massive unmet need among early Alzheimer’s patients, he pointed out.
“Alzheimer’s is really the competition here, and so building that market is really our first priority,” Lechleiter said.
The coverage equation
Lilly's drug arrives at somewhat of an opportune time, given that the Centers for Medicare and Medicaid Services (CMS) last summer rolled back its strict national coverage determination for amyloid-targeting Alzheimer’s meds.
While the coverage revamp doesn’t mean everything will be smooth sailing from now on out, it does represent “a massive barrier that has been removed,” Lechleiter said.
Last summer, CMS blueprinted plans to broadly cover the new class of Alzheimer’s disease drugs that includes Kisunla and Leqembi once the therapies win full approval at the FDA. As part of the framework, the drugmakers behind the Alzheimer’s meds must enroll patients in real-world data collection registries to support the ongoing merit of their products.
“Our hope is that the Medciare registry portal includes customers very quickly and we have the intention of that happening and then ensuring that reimbursement is a smooth process for those clinics and institutions that would like to use Kisunla for the appropriate patients,” Lechleiter said.
CMS released the latest coverage decision after issuing a narrower coverage framework in 2022 for Leqembi's failed predecessor, Aduhelm. Under that coverage framework, CMS said new Alzheimer's antibodies approved under the FDA’s accelerated pathway would only be covered when administered in eligible clinical trials.
Lechleiter did acknowledge potential remaining hurdles to treatment like high out-of-pocket costs for some patients, as well as geographic access to the diagnostics required to qualify for treatment.
Stopping treatment and looking to the future
Beyond the fact that the drug is infused once a month rather than biweekly like Leqembi, Kisunla could offer a major convenience edge insofar as the antibody can potentially be stopped once patients have brought their amyloid levels down successfully, Brooks explained.
Pointing to Lilly’s TRAILBLAZER trial for Kisunla, Brooks noted that certain patients were able to stop treatment as soon as six months after initiating therapy.
“We continued to follow those patients in the course of the 18-month study and found that the trajectory of those compared to placebo continued to widen, meaning that you were on a disease-modifying trajectory compared to those that hadn’t received treatment at all,” she explained.
At the same time, Lilly is also run a long-term extension study to track Kisunla’s broader effects on patients’ memory and thinking over time.
The main takeaway on potential Kisunla stoppage, to hear Brooks tell it, is that amyloid re-accumulation seems to occur “at a very slow rate.”
Plaque typically accumulates over 10 to 20 years, but once that block has been cleared or brought down to acceptable levels, “it also re-accumulates at that same very slow rate,” Brooks pointed out.
“We would expect that it’s going to be many years before you’re back in a position of it being a positive level,” which shouldn’t be a near-term concern for patients, Brooks said.
As for what comes next in the field, Lilly is currently working on its TRAILBLAZER ALZ-3 study, which is looking at whether Kisunla could prevent the onset of symptoms associated with Alzheimer’s disease, Brooks pointed out. The primary measure for that study is expected to read out in October of 2027.