Table of Contents As filed with the Securities and Exchange Commission on April 18, 2024 Registration No. 333- UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 Spyre Therapeutics, Inc. (Exact name of registrant as specified in its charter) Delaware 46-4312787 (State or other jurisdiction of incorporation or organization) (I.R.S. Employer Identification No.) 221 Crescent Street Building 23, Suite 105 Waltham, MA 02453 (61 ...

Table of Contents As filed with the Securities and Exchange Commission on March 26, 2024 Registration No. 333-276251 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 PRE-EFFECTIVE AMENDMENT NO. 4 TO FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 Spyre Therapeutics, Inc. (Exact name of registrant as specified in its charter) Delaware 46-4312787 (State or other jurisdiction of incorporation or organization) (I.R.S. Employer Identification No.) 221 Crescent Street Build ...

Table of Contents As filed with the Securities and Exchange Commission on March 14, 2024 Registration No. 333-276251 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 PRE-EFFECTIVE AMENDMENT NO. 3 TO FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 Spyre Therapeutics, Inc. (Exact name of registrant as specified in its charter) Delaware 46-4312787 (State or other jurisdiction of incorporation or organization) (I.R.S. Employer Identification No.) 221 Crescent Street Build ...

As filed with the Securities and Exchange Commission on March 1, 2024 Registration No. 333-276251 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 PRE-EFFECTIVE AMENDMENT NO. 2 TO FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 Spyre Therapeutics, Inc. 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 regist ...

Table of Contents As filed with the Securities and Exchange Commission on November 15, 2023 Registration No. 333-273769 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 AMENDMENT NO. 1 TO FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 Aeglea BioTherapeutics, Inc. (Exact name of registrant as specified in its charter) Delaware 46-4312787 (State or other jurisdiction of incorporation or organization) (I.R.S. Employer Identification No.) 221 Crescent Street Building 23, ...

Table of Contents As filed with the Securities and Exchange Commission on October 6, 2023 Registration No. 333-273769 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 PRE-EFFECTIVE AMENDMENT NO. 1 TO FORM S-3 ON FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 Aeglea BioTherapeutics, Inc. 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 bo ...