X0306 4 2022-06-07 0 0001828522 eFFECTOR Therapeutics, Inc. EFTR 0001283307 WORLAND STEPHEN T C/O EFFECTOR THERAPEUTICS, INC. 142 NORTH CEDROS AVENUE, SUITE B SOLANA BEACH CA 92075 1 1 0 0 President and Chief Executive Common Stock 2022-06-07 4 P 0 20000 1.37 A 214978 D Common Stock 562339 I By Trust The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $1.34 to $1.39. The reporting person undertakes to provide the Company, any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth in this footnote. /s/ Michael Byrnes, Attorney-in-Fact for Stephen T. Worland 2022-06-09