X0306 4 2021-02-16 false 0001560241 G1 Therapeutics, Inc. GTHX 0001706847 Velleca Mark A. 700 PARK OFFICES DRIVE, SUITE 200 RESEARCH TRIANGLE PARK NC 27709 true false false false Common Stock 2021-02-16 4 M false 11040.00 3.72 A 52040.00 D Common Stock 2021-02-16 4 S false 8317.00 34.8709 D 43723.00 D Common Stock 2021-02-16 4 S false 2700.00 36.215 D 41023.00 D Common Stock 2021-02-16 4 S false 23.00 37.00 D 41000.00 D Common Stock 2021-02-17 4 M false 10000.00 3.72 A 51000.00 D Common Stock 2021-02-17 4 S false 9400.00 27.5944 D 41600.00 D Common Stock 2021-02-17 4 S false 600.00 28.41 D 41000.00 D Common Stock 2021-02-18 4 M false 10000.00 3.72 A 51000.00 D Common Stock 2021-02-18 4 S false 10000.00 26.0152 D 41000.00 D Stock Options (Right to Buy) 3.72 2021-02-16 4 M false 11040.00 0.00 D 2025-12-21 Common Stock 11040.00 48393.00 D Stock Options (Right to Buy) 3.72 2021-02-17 4 M false 10000.00 0.00 D 2025-12-21 Common Stock 10000.00 38393.00 D Stock Options (Right to Buy) 3.72 2021-02-18 4 M false 10000.00 0.00 D 2025-12-21 Common Stock 10000.00 28393.00 D This sale was effected pursuant to a Rule 10b5-1 trading plan. The price represents the weighted average price with a low of $34.71 and a high of $35.36. The Reporting Person undertakes to provide G1 Therapeutics, Inc., any security holder of G1 Therapeutics, 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 range set forth in footnote 2 to this Form 4. The price represents the weighted average price with a low of $35.84 and a high of $36.785. The Reporting Person undertakes to provide G1 Therapeutics, Inc., any security holder of G1 Therapeutics, 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 range set forth in footnote 3 to this Form 4. The price represents the weighted average price with a low of $27.25 and a high of $28.21. The Reporting Person undertakes to provide G1 Therapeutics, Inc., any security holder of G1 Therapeutics, 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 range set forth in footnote 4 to this Form 4. The price represents the weighted average price with a low of $28.40 and a high of $28.42. The Reporting Person undertakes to provide G1 Therapeutics, Inc., any security holder of G1 Therapeutics, 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 range set forth in footnote 5 to this Form 4. The price represents the weighted average price with a low of $25.88 and a high of $26.31. The Reporting Person undertakes to provide G1 Therapeutics, Inc., any security holder of G1 Therapeutics, 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 range set forth in footnote 6 to this Form 4. All shares underlying this option have vested. /s/ James Stillman Hanson, attorney-in-fact 2021-02-18