X0306 4 2017-12-01 0 0001636282 Aeglea BioTherapeutics, Inc. AGLE 0001532219 Quinn Anthony G. C/O AEGLEA BIOTHERAPEUTICS, INC. 901 S. MOPAC EXPRESSWAY, SUITE 250 AUSTIN TX 78746 1 0 0 0 Common Stock 2017-12-01 4 P 0 4100 4.5312 A 14100 D Common Stock 2017-12-04 4 P 0 7956 4.9804 A 22056 D Common Stock 2017-12-05 4 P 0 5065 4.9310 A 27121 D Represents a weighted average purchase price per share. These shares were purchased in multiple transactions at prices ranging from $4.29 to $4.60 per share. The Reporting Person has provided to the Issuer, and undertakes to provide to the staff of the Securities and Exchange Commission or any security holder of the Issuer, upon request, full information regarding the number of shares purchased at each separate price within the range. Represents a weighted average purchase price per share. These shares were purchased in multiple transactions at prices ranging from $4.85 to $5.05 per share. The Reporting Person has provided to the Issuer, and undertakes to provide to the staff of the Securities and Exchange Commission or any security holder of the Issuer, upon request, full information regarding the number of shares purchased at each separate price within the range. Represents a weighted average purchase price per share. These shares were purchased in multiple transactions at prices ranging from $4.70 to $5.10 per share. The Reporting Person has provided to the Issuer, and undertakes to provide to the staff of the Securities and Exchange Commission or any security holder of the Issuer, upon request, full information regarding the number of shares purchased at each separate price within the range. /s/ Charles N. York II, by power of attorney 2017-12-05