AIC-468

Asahi Kasei has agreed to acquire Germany-based Aicuris Anti-infective Cures AG for approximately EUR 780 million (USD 919 million), strengthening the Japanese group’s infectious disease portfolio focused on immunocompromised patients. The transaction will see Asahi Kasei purchase all issued shares of Aicuris and is expected to close by June 2026, subject to customary conditions. The acquisition adds a pipeline of antiviral therapies targeting infections common in transplant recipients and other immunocompromised populations, complementing Asahi Kasei’s existing presence in transplantation and nephrology. Aicuris pipeline and technologies Aicuris brings three key antiviral assets to Asahi Kasei. Prevymis (letermovir), a cytomegalovirus (CMV) terminase inhibitor discovered by Aicuris, is marketed globally by Merck under license. The drug is approved for CMV prophylaxis in transplant patients, and Aicuris receives royalties as the originator. These royalty revenues will transfer to Asahi Kasei after the acquisition closes. Pritelivir is a helicase-primase inhibitor targeting herpes simplex virus (HSV) infections in immunocompromised patients. The mechanism differs from nucleoside analog antivirals such as acyclovir, enabling activity against drug-resistant HSV strains. Pritelivir has received FDA Fast Track and Breakthrough Therapy designations, and Phase III studies have been completed, with a regulatory submission anticipated in 2026. The company’s earlier-stage program, AIC468, is an antisense oligonucleotide designed to inhibit replication of BK virus (BKV) in kidney transplant recipients. The therapy has completed Phase I development. No antiviral therapies are currently approved in the United States for BK virus infection. Strategic expansion in transplant and nephrology The acquisition continues Asahi Kasei’s strategy of building a specialty pharmaceutical platform focused on diseases affecting transplant recipients and kidney patients. The company acquired Veloxis Pharmaceuticals in 2020 for USD 1.3 billion, gaining the transplant immunosuppressant Envarsus XR, and Calliditas Therapeutics in 2024 for approximately USD 1.1 billion, adding Tarpeyo for IgA nephropathy. With Aicuris, Asahi Kasei expands into antiviral treatments for infections that frequently complicate transplantation, including CMV reactivation, HSV disease, and BK virus nephropathy. These infections remain significant clinical risks in transplant recipients despite advances in immunosuppressive therapy. Market and competitive landscape The antiviral pipeline targeting transplant-associated infections has drawn increasing industry interest in recent years. Programs in development include BK virus therapies such as MAU868, a monoclonal antibody currently in clinical trials, and next-generation HSV antivirals being developed by companies including Assembly Biosciences. Against this backdrop, the Aicuris acquisition provides Asahi Kasei with a combination of near-term commercial potential through pritelivir, existing royalty revenue from letermovir, and earlier-stage pipeline assets, strengthening its position in transplant medicine. The company expects the acquisition to contribute to operating income beginning in fiscal 2028, as it builds a broader pharmaceutical portfolio spanning transplantation, nephrology, and infectious diseases.