X0306 4 2018-08-15 0 0001113148 INFINITY PHARMACEUTICALS, INC. INFI 0001697644 Kutok Jeffery C/O INFINITY PHARMACEUTICALS, INC. 784 MEMORIAL DRIVE CAMBRIDGE MA 02139 0 1 0 0 Chief Scientific Officer Common Stock 2018-08-15 4 S 0 8180 2.0074 D 6133 D Common Stock 2018-08-16 4 S 0 6133 2.00 D 0 D Common Stock 9542.3224 I 401(k) The dispositions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 29, 2018. The price reported in this line of Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $2.00 to $2.0200, inclusive. The reporting person undertakes to provide to Infinity Pharmaceuticals, Inc., any security holder of Infinity Pharmaceuticals, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote 2. /s/ Jeffery Kutok 2018-08-17