Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in the Registration Statements on Form S-8 (No.

333-278333, 333-271737, and 333-283209) of ACELYRIN, INC. of our report dated March 19, 2025relating to the financial statements, which appears in this Form 10-K.

/s/ PricewaterhouseCoopers LLP

San Diego, California March 19, 2025