Some two years into Leqembi’s launch, Eisai continues to go all-in on its Alzheimer’s disease-fighting antibody, which the company believes could be finally nearing a “growth expansion phase” despite slow sales so far in the U.S.
All told, Leqembi brought home around 13.3 billion Japanese yen ($87 million) in the third quarter of Eisai’s 2024 fiscal year, which will wrap up on March 31. In the U.S. specifically, Leqembi grew roughly 30% quarter-over-quarter to 7.7 billion yen (nearly $51 million), Eisai said in a recent earnings presentation (PDF).
Cumulatively, the antibody has generated total sales of 29.6 billion yen (about $194 million) over the last nine months of 2024, putting Leqembi on track to reach a 12-month sales target of 42.5 billion yen ($279 million), Eisai’s chairman and CEO, Tatsuyuki Yasuno, said in an interview with Fierce Pharma.
Leqembi is generally performing better—and growing faster—in other territories like Japan and China, where the medicine lifted quarterly sales nearly 50% to 4.1 billion yen ($27 million) and 33% to 1.5 billion yen ($9.9 million), respectively. Leqembi’s China performance also includes sales from certain other regions in Asia where the drug is approved.
Nevertheless, a confluence of forces—including the advent of better blood-based diagnostics and progress toward the approval of easier dosing formats—gives Eisai good reason to believe Leqembi could be approaching a “growth expansion phase,” Keisuke Naito, the company’s chief operating and growth officer, said on a Japanese-language earnings call Friday.
To hear Eisai’s CEO Yasuno tell it, “the Leqembi business is continuously growing stronger,” and that’s becoming especially clear in the U.S., where the medicine has now reached 13,500 patients.
Additionally, Leqembi is now operating from a base of more than 3,000 U.S. prescribers and being purchased by around 1,200 medical institutions in the country, the CEO pointed out.
As interest in Leqembi grows, Eisai has been working to expand infusion capacity for the antibody, as Yasuno cited an “excellent early sign for patient demand.”
Meanwhile, the use of diagnostics continues to be critical in the quest to ensure the right patients receive Leqembi at the proper time.
Yasuno pointed out that several companies have already submitted or are preparing to submit FDA filings for more accurate blood-based diagnostics. Eisai expects that regulators will allow blood-based biomarkers as confirmatory tests for amyloid beta during the company’s upcoming 2025 fiscal year, Yasuno added.
Currently, those biomarkers can be used to support an Alzheimer’s diagnosis, but they must be followed up with confirmatory positron emission tomography (PET) or cerebrospinal fluid (CSF) tests.
As for the role diagnostics are already playing in the Leqembi treatment ecosystem, COO Naito flagged on last week’s earnings call that Eisai noted a 45% increase in amyloid beta PET testing in the last three months of 2024 versus the previous quarter.
“We believe that the increase is due to the growing awareness of the significance of early diagnosis of dementia, the spread of use of guidelines for amyloid beta PET tests that support early diagnosis and the increase in use of [blood-based biomarkers] as a prescreening tool,” Naito said.
Since Leqembi’s initial FDA green light in 2023, Eisai has been working to make the drug less burdensome for patients and caregivers managing a chronic disease.
To that end, the company last month scored an approval in the U.S. for an IV maintenance dosing schedule that only needs to be administered once every four weeks, versus the biweekly dosing schedule under which Leqembi was originally approved.
The new dosing green light should make it easier for patients and caregivers to continue treatment and may even entice new patients to give Leqembi a shot thanks to the easier administration schedule, Katsuya Haruna, senior group officer and EVP of Eisai’s U.S. business operations, said during the interview.
“Maintenance dosing is important because we know Alzheimer’s disease does not stop after plaque is removed,” Haruna said, alluding to Leqembi’s ability to clear amyloid-beta proteins in the brain. “Patients deserve a therapy that offers them the opportunity to continuously treat this chronic and fatal disease.”
As for why Leqembi fits the bill for that purpose, Eisai’s antibody can clear not just plaque, but also protofibrils—peptide assemblies that aggregate in the brain and eventually become amyloid plaque, Haruna explained.
Eisai has highlighted Leqembi’s dual-action profile in the past as a potential edge over Eli Lilly’s rival Alzheimer’s med Kisunla, which only targets plaque and can be discontinued once a patient’s amyloid build-up is cleared.
“In terms of market share perspective, we don’t expect [Leqembi] to lose unit share from the competitors,” Haruna said of the current commercial environment for Alzheimer’s disease drugs.
Amid multiple efforts to grow Leqembi’s influence, Eisai has also set out to work more closely with primary care physicians moving forward.
While the company has noticed a recent uptick in patient referrals from primary care physicians, the quality of those referrals hasn’t always been great, with neurologists sometimes receiving recommendations for patients who don’t qualify for Eisai’s drug, Haruna noted.
To help bridge the gap, Eisai aims to soon kick off more primary care education, which will include instruction on how to urgently and accurately identify potentially eligible patients, Haruna said.
Overall, Eisai generated 601.2 billion yen (nearly $4 billion) over the last nine months of 2024, signaling 9% growth year-on-year. For the entire 12-month stretch ending March 31, the company aims to bring home net sales of around 754 billion yen (nearly $5 billion).
Eisai is partnered on Leqembi with Biogen. Under the collaboration, Eisai is in charge of development and regulatory matters tied to the drug, while both Eisai and Biogen co-commercialize and promote the product.