Trium Capital LLP → ACELYRIN, Inc.

Item 4 of the Schedule 13D is hereby amended by adding the following thereto: On 28th April 2025, Trium Capital LLP delivered a letter (the "Letter") to the Special Committee of the Board of Directors of Acelyrin Inc. A copy of the Letter is attached hereto as Exhibit 1. Trium Capital LLP intends to have conversations, meetings and other communications with the management of Acelyrin Inc, shareholders and other persons, in each case to discuss the Merger, Acelyrin Inc's business, operations, strategy, governance and related matters. These communications may include a discussion of options for enhancing shareholder value, including the matters discussed in the Letter.