S-1MEF

Large accelerated filer

Accelerated filer

Non-accelerated filer

Smaller reporting company

Emerging growth company

As filed with the Securities and Exchange Commission on May 4, 2023.

Registration No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM S-1

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

ACELYRIN, INC.

(Exact name of registrant as specified in its charter)

Delaware

2834

82-2406735

(State or other jurisdiction of

incorporation or organization)

(Primary Standard Industrial

Classification Code Number)

(I.R.S. Employer

Identification Number)

ACELYRIN, INC.

4149 Liberty Canyon Road

Agoura Hills, California 91301

(805) 730-0360

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Shao-Lee Lin, M.D., Ph.D.

Chief Executive Officer

4149 Liberty Canyon Road

Agoura Hills, California 91301

(805) 730-0360

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Chadwick Mills

Charles S. Kim

Anitha Anne

Cooley LLP

3 Embarcadero Center, 20th Floor

San Francisco, California 94111

(415) 693-2000

Mardi C. Dier

Chief Financial Officer and
Chief Business Officer
4149 Liberty Canyon Road
Agoura Hills, California 91301
(805) 730-0360

Alan F. Denenberg

Emily Roberts

Davis Polk & Wardwell LLP

1600 El Camino Real

Menlo Park, California 94025
(650) 752-2000

Approximate date of commencement of proposed sale to the public: As soon as practicable after this registration statement becomes effective.

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933 check the following box: ☐

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☒ (333-271244)

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

The Registration Statement shall become effective upon filing in accordance with Rule 462(b) promulgated under the Securities Act of 1933, as amended.

EXPLANATORY NOTE AND INCORPORATION BY REFERENCE

This Registration Statement is being filed pursuant to Rule 462(b) under the Securities Act of 1933, as amended (the “Securities Act”), for the sole purpose of increasing the aggregate number of shares of common stock offered by ACELYRIN, INC. (the “Registrant”) by 4,025,000 shares, 525,000 of which are subject to purchase upon exercise of the underwriters’ option to purchase additional shares of the Registrant’s common stock. The contents of the Registration Statement on Form S-1, as amended (File No. 333-271244), including all exhibits thereto (the “Earlier Registration Statement”), filed by the Registrant with the Securities and Exchange Commission (the “Commission”) pursuant to the Securities Act, which was declared effective by the Commission on May 4, 2023, are incorporated by reference into this Registration Statement. The additional shares of common stock that are being registered for issuance and sale pursuant to this Registration Statement are in an amount and at a price that together represent no more than 20% of the maximum aggregate offering price set forth in Exhibit 107 of the Earlier Registration Statement.

The required opinion and consents are listed on an Exhibit Index attached hereto and filed herewith.

EXHIBIT INDEX


Exhibit No.		Exhibit Index

5.1		Opinion of Cooley LLP.

23.1		Consent of PricewaterhouseCoopers LLP, independent registered public accounting firm of ACELYRIN, INC.

23.2		Consent of PricewaterhouseCoopers LLP, independent registered public accounting firm of ValenzaBio, Inc.

23.3		Consent of Macias Gini & O’Connell LLP, independent auditor of ValenzaBio, Inc.

23.4		Consent of Cooley LLP (included in Exhibit 5.1).

24.1*		Power of Attorney.

107		Filing Fee Table.

*	Previously filed on the signature page to the Registrant’s Registration Statement on Form S-1 (File No. 333-271244), originally filed with the Securities and Exchange Commission on April 13, 2023 and incorporated by reference herein.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Agoura Hills, California on May 4, 2023.


ACELYRIN, INC.

By:		/s/ Shao-Lee Lin
Name:		Shao-Lee Lin, M.D., Ph.D.
Title:		Chief Executive Officer

POWER OF ATTORNEY

Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.


Signature	Title	Date

/s/ Shao-Lee Lin Shao-Lee Lin, M.D., Ph.D.	Founder, Chief Executive Officer and Director (Principal Executive Officer)	May 4, 2023

/s/ Mardi C. Dier Mardi C. Dier	Chief Financial Officer and Chief Business Officer (Principal Financial and Accounting Officer)	May 4, 2023

* Bruce C. Cozadd	Director	May 4, 2023

* Dan Becker, M.D., Ph.D.	Director	May 4, 2023

* Alan B. Colowick, M.D., M.P.H.	Director	May 4, 2023

* Henry O. Gosebruch	Director	May 4, 2023

* Patrick Machado, J.D.	Director	May 4, 2023

* Beth Seidenberg, M.D.	Director	May 4, 2023

* Dawn Svoronos	Director	May 4, 2023


*By:		/s/ Shao-Lee Lin
		Shao-Lee Lin, M.D., Ph.D.
		Attorney-in-fact