X0306 4 2023-01-19 0 0001783183 Phathom Pharmaceuticals, Inc. PHAT 0001690298 Curran Terrie C/O PHATHOM PHARMACEUTICALS, INC. 100 CAMPUS DRIVE, SUITE 102 FLORHAM PARK NJ 07932 1 1 0 0 President and Chief Executive Common Stock 2023-01-19 4 A 0 97500 0.00 A 182628 D Common Stock 2023-01-20 4 S 0 5821 8.1995 D 176807 D Common Stock 2235.9 I by 401(k) Stock Option (Right to Buy) 8.35 2023-01-19 4 A 0 162500 0.00 A 2033-01-18 Common Stock 162500 162500 D Represents restricted stock units ("RSUs") granted on January 19, 2023. One third (1/3) of the total number of RSUs granted vest on each of the first three anniversaries of January 19, 2023, the vesting commencement date, subject to the Reporting Person's continued service on the applicable vesting date. Each RSU represents a contingent right to receive one share of common stock of the Issuer. Includes 1,408 shares acquired under the Phathom Pharmaceuticals, Inc. employee stock purchase plan in January 2023. Represents shares sold to satisfy tax withholding obligations upon the settlement of restricted stock units. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $8.16 to $8.20. The reporting person undertakes to provide the Issuer, any security holder of the Company, 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 range set forth in this footnote. The stock option will vest with respect to 25% of the shares of common stock on January 19, 2024, and will vest with respect to the remaining shares in equal monthly installments over the following three years, subject to the reporting person's continuous service to the Company on the applicable vesting dates. /s/ Larry Miller, Attorney-in-Fact for Terrie Curran 2023-01-20