X0306 4 2020-12-15 0 0001731831 Eidos Therapeutics, Inc. EIDX 0001758363 Turtle Cameron C/O EIDOS THERAPEUTICS, INC. 101 MONTGOMERY STREET, SUITE 2000 SAN FRANCISCO CA 94104 0 1 0 0 Chief Business Officer Common Stock 2020-12-15 4 M 0 4451 17.00 A 55072 D Common Stock 2020-12-15 4 M 0 21843 13.20 A 76915 D Common Stock 2020-12-15 4 S 0 3756 110.2906 D 73159 D Common Stock 2020-12-15 4 S 0 7600 111.3075 D 65559 D Common Stock 2020-12-15 4 S 0 11445 112.1903 D 54114 D Common Stock 2020-12-15 4 S 0 3493 112.9657 D 50621 D Stock Option (Right to Buy) 17.00 2020-12-15 4 M 0 4451 0.00 D 2028-06-20 Common Stock 4451 9469 D Stock Option (Right to Buy) 13.20 2020-12-15 4 M 0 21843 0.00 D 2028-11-05 Common Stock 21843 53157 D Represents the weighted average sale price of the shares sold from $109.71 to $110.70 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 for all transactions as reported in footnotes 1 through 4. Represents the weighted average sale price of the shares sold from $110.73 to $111.71 per share. Represents the weighted average sale price of the shares sold from $111.73 to $112.72 per share. Represents the weighted average sale price of the shares sold from $112.73 to $113.59 per share. 25% of the shares subject to this option vested and became exercisable on November 5, 2019 and the remainder vests in 36 equal monthly installments thereafter, subject to the Reporting Person's continuous service to the Issuer through each such vesting date. The shares subject to this option vest and become exercisable in 48 equal monthly installments following June 18, 2018, subject to the Reporting Person's continuous service to the Issuer through each such vesting date. /s/ Franco Valle, Attorney-in-Fact 2020-12-16