X0508 4 2024-01-18 0 0001783183 Phathom Pharmaceuticals, Inc. PHAT 0001363812 Henderson Molly C/O PHATHOM PHARMACEUTICALS, INC. 100 CAMPUS DRIVE, SUITE 102 FLORHAM NJ 07932 0 1 0 0 CFO and CBO 0 Common Stock 2024-01-19 4 S 0 6307 7.7533 D 98698 D Common Stock 1911.27 I By 401(k) Stock Option (Right to Buy) 7.60 2024-01-18 4 A 0 120000 0.00 A 2034-01-17 Common Stock 120000 120000 D Represents shares sold to satisfy tax withholding obligations upon the settlement of restricted stock units. Includes 1,944 shares acquired under the Phathom Pharmaceuticals, Inc. employee stock purchase plan in January 2024. The stock option will vest with respect to 25% of the shares of common stock on January 18, 2025, 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 Molly Henderson 2024-01-22