X0306 4 2018-04-24 0 0001581720 Loxo Oncology, Inc. LOXO 0001612312 Bilenker Joshua H. C/O LOXO ONCOLOGY, INC. 281 TRESSER BOULEVARD, 9TH FLOOR STAMFORD CT 06901 1 1 0 0 President & CEO Common Stock 2018-04-24 4 M 0 7500 1.184 A 190207 D Common Stock 2018-04-24 4 S 0 1717 129.3516 D 188490 D Common Stock 2018-04-24 4 S 0 1283 130.6232 D 187207 D Common Stock 2018-04-24 4 S 0 1500 131.7567 D 185707 D Common Stock 2018-04-24 4 S 0 2490 132.5426 D 183217 D Common Stock 2018-04-24 4 S 0 510 133.4851 D 182707 D Common Stock 2018-04-25 4 M 0 7500 1.184 A 190207 D Common Stock 2018-04-25 4 S 0 800 128.3045 D 189407 D Common Stock 2018-04-25 4 S 0 800 129.4438 D 188607 D Common Stock 2018-04-25 4 S 0 2400 130.7121 D 186207 D Common Stock 2018-04-25 4 S 0 3400 131.8418 D 182807 D Common Stock 2018-04-25 4 S 0 100 132.53 D 182707 D Employee Stock Option (right to buy) 1.184 2018-04-24 4 M 0 7500 0 D 2023-11-14 Common Stock 7500 37190 D Employee Stock Option (right to buy) 1.184 2018-04-25 4 M 0 7500 0 D 2023-11-14 Common Stock 7500 29690 D The transactions reported on this Form 4 were effected pursuant to a 10b5-1 trading plan adopted by the reporting person. Represents the aggregate of sales effected on the same day at different prices. Represents the weighted average sales price per share. The shares sold at prices ranging from $129.03 to $129.66 per share. Full information regarding the number of shares sold at each price shall be provided upon request to the staff of the U.S. Securities and Exchange Commission, the Issuer, or a security holder of the Issuer. Represents the weighted average sales price per share. The shares sold at prices ranging from $130.07 to $131.03 per share. Full information regarding the number of shares sold at each price shall be provided upon request to the staff of the U.S. Securities and Exchange Commission, the Issuer, or a security holder of the Issuer. Represents the weighted average sales price per share. The shares sold at prices ranging from $131.10 to $132.09 per share. Full information regarding the number of shares sold at each price shall be provided upon request to the staff of the U.S. Securities and Exchange Commission, the Issuer, or a security holder of the Issuer. Represents the weighted average sales price per share. The shares sold at prices ranging from $132.10 to $133.05 per share. Full information regarding the number of shares sold at each price shall be provided upon request to the staff of the U.S. Securities and Exchange Commission, the Issuer, or a security holder of the Issuer. Represents the weighted average sales price per share. The shares sold at prices ranging from $133.19 to $133.91 per share. Full information regarding the number of shares sold at each price shall be provided upon request to the staff of the U.S. Securities and Exchange Commission, the Issuer, or a security holder of the Issuer. Represents the weighted average sales price per share. The shares sold at prices ranging from $127.825 to $128.77 per share. Full information regarding the number of shares sold at each price shall be provided upon request to the staff of the U.S. Securities and Exchange Commission, the Issuer, or a security holder of the Issuer. Represents the weighted average sales price per share. The shares sold at prices ranging from $128.99 to $129.98 per share. Full information regarding the number of shares sold at each price shall be provided upon request to the staff of the U.S. Securities and Exchange Commission, the Issuer, or a security holder of the Issuer. Represents the weighted average sales price per share. The shares sold at prices ranging from $130.19 to $131.18 per share. Full information regarding the number of shares sold at each price shall be provided upon request to the staff of the U.S. Securities and Exchange Commission, the Issuer, or a security holder of the Issuer. Represents the weighted average sales price per share. The shares sold at prices ranging from $131.43 to $132.34 per share. Full information regarding the number of shares sold at each price shall be provided upon request to the staff of the U.S. Securities and Exchange Commission, the Issuer, or a security holder of the Issuer. The stock option is immediately exercisable in full, and vests as to 25% of the shares subject to the option on the one-year anniversary of the vesting commencement date, and thereafter as to 1/48th of the shares in equal monthly installments. /s/ Jennifer Burstein, by power of attorney 2018-04-26