X0306 4 2021-01-13 0 0001731831 Eidos Therapeutics, Inc. EIDX 0001742587 Sinha Uma C/O EIDOS THERAPEUTICS, INC. 101 MONTGOMERY STREET, SUITE 2000 SAN FRANCISCO CA 94104 1 1 0 0 Chief Scientific Officer Common Stock 2021-01-13 4 S 0 696 121.1094 D 315829 D Common Stock 2021-01-13 4 S 0 572 122.2667 D 315257 D Common Stock 2021-01-13 4 S 0 1498 123.4787 D 313759 D Common Stock 2021-01-13 4 S 0 4934 124.7187 D 308825 D Common Stock 2021-01-13 4 S 0 2000 125.35 D 306825 D Common Stock 2021-01-13 4 S 0 300 126.39 D 306525 D This transaction was effected pursuant to a Rule 10b5-1 Sales Plan adopted by the Reporting Person on August 13, 2020. Represents the weighted average sale price of the shares sold ranging from $120.81 to $121.33 per share. The Reporting Person will provide, upon request by the Commission staff, the Issuer or a security holder of the Issuer, full information regarding the number of shares sold at each separate price within the ranges set forth in footnotes 2 through 7. Represents the weighted average sale price of the shares sold ranging from $121.98 to $122.89 per share. Represents the weighted average sale price of the shares sold ranging from $123.01 to $124.00 per share. Represents the weighted average sale price of the shares sold ranging from $124.10 to $125.09 per share. Represents the weighted average sale price of the shares sold ranging from $125.11 to $125.66 per share. Represents the weighted average sale price of the shares sold ranging from $126.30 to $126.57 per share. /s/ Franco Valle, Attorney-in-Fact 2021-01-14