Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in this Registration Statement on Form S-3 of ACELYRIN, INC. of our report dated March 28, 2024 relating to the financial statements, which appears in ACELYRIN, INC.’s Annual Report on Form 10-K for the year ended December 31, 2023. We also consent to the reference to us under the heading “Experts” in such Registration Statement.

/s/ PricewaterhouseCoopers LLP

San Diego, California

November 13, 2024

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