BRII-B (02137) has announced that on May 23, 2018, the company, its Cayman Islands subsidiary (collectively referred to as BRII), and Vir Biotechnology, Inc. (Vir), a company incorporated in Delaware and operating in San Francisco, California, entered into a Collaboration, Option and License Agreement. Under this agreement, each party holds an option to obtain an exclusive license to advance the development and commercialization of certain products initially researched by the other party. On June 12, 2020, BRII exercised its option for the elebsiran program, a small interfering RNA (siRNA) candidate targeting the hepatitis B virus. On December 19, 2024, BRII and Vir signed a sixth letter agreement to transfer drug product manufacturing responsibilities from Vir to BRII. On April 16, 2026, regarding contractual disputes arising from the collaboration agreement and related letters, BRII filed an arbitration claim against Vir with Judicial Arbitration and Mediation Services, Inc. in the United States, alleging that Vir breached the terms of the collaboration agreement and the letter agreements. The company issued an announcement concerning this arbitration on April 16, 2026. As of the date of this announcement, the arbitration remains in its early stages, and BRII and Vir have not reached a settlement regarding the claims. Given the ongoing delays to the elebsiran program due to the dispute related to Vir's actions, and considering the uncertainty surrounding the outcome of the arbitration or the terms and timing of any potential settlement, the company views the future prospects of the elebsiran program as uncertain. In particular, unless and until the claims in the arbitration are resolved satisfactorily, BRII will be unable to invest in any Phase 3 clinical studies for hepatitis B combination therapies containing elebsiran. The company will continue to assess relevant developments, evaluate their impact on the prospects for advancing the elebsiran program, and will provide updates to its shareholders and the public as appropriate in accordance with relevant regulations.