Eisai Forecasts Leqembi® Sales to Reach JPY 143.5 Billion by 2027

Eisai's Strong Sales Projection for Leqembi®

Eisai Co., Ltd., in collaboration with BioArctic AB, has announced a significant projection regarding its Alzheimer's disease treatment, Leqembi® (lecanemab). The company estimates that sales for the fiscal year 2026, which spans from April 2026 to March 2027, will reach an astounding JPY 143.5 billion. This projection represents a 63% increase compared to the previous fiscal year, underscoring the growing demand for innovative treatments in the Alzheimer's space.

Background on Leqembi®

Leqembi is a result of a strategic partnership between BioArctic and Eisai, with its development rooted in the discovery by Professor Lars Lannfelt, a key figure in Alzheimer's research. The monoclonal antibody is designed to target aggregated forms of amyloid-beta, a protein implicated in Alzheimer's disease progression. Eisai oversees the clinical development, regulatory authorizations, and commercialization of Leqembi globally, while BioArctic retains rights for Nordic commercialization.

Financial Implications

The projected sales figure of JPY 143.5 billion translates to approximately SEK 8.4 billion, boosting BioArctic’s revenues significantly as it stands to gain around SEK 880 million in royalties over the same period. This financial forecast comes amid growing global attention on Alzheimer’s treatments, as more patients and healthcare systems seek effective solutions for managing this devastating condition.

Regulatory and Clinical Developments

Leqembi has received approval in 53 countries and is currently under review in six others. Following its initial treatment phase, the drug also offers a maintenance dosing plan approved in multiple countries, including the US, UK, and Japan. Eisai's continuous efforts in clinical studies, such as the AHEAD 3-45 trial, aim to evaluate the drug's efficacy in people with preclinical Alzheimer’s disease, demonstrating commitment to advancing Alzheimer's research further.

In addition to addressing the current regulatory landscape, Eisai's recent applications for subcutaneous formulations of Leqembi are designed to enhance accessibility for patients who may struggle with intravenous treatments. The anticipation of these new formulations has the potential to further increase uptake and adherence among patients.

Partnership Growth

Since entering into collaboration in 2005, BioArctic and Eisai have closely connected their strategic goals to address Alzheimer’s disease comprehensively. Their partnership has resulted in multiple agreements, including those for the commercialization of lecanemab. Notably, BioArctic bears no development expenses for the antibody, allowing it to directly benefit from sales milestones and global royalties without the financial burden of drug development, emphasizing a successful partnership model in biopharmaceuticals.

The Future of Leqembi®

Eisai’s projections for Leqembi signal increasing optimism within the biopharmaceutical community about the potential for treatments in neurodegenerative diseases. As the healthcare landscape evolves, the focus remains on improving patient outcomes and providing effective solutions to one of society's most pressing health challenges.

The first-quarter report for BioArctic for 2026 is set to be published on May 20, 2026, providing further insights into the ongoing developments within this exciting collaboration.

In summary, Eisai's sales forecast for Leqembi not only showcases robust financial growth but also highlights the continued advancements in Alzheimer’s treatment options. With a strategic alliance and ongoing research, both BioArctic and Eisai are poised to play central roles in reshaping the future of Alzheimer’s care.