XLO

SEC source: 0001193125-25-297203 · ownership.xml · derivative · entry 5

Russo Rene · CIK 0001722066 · Director · PRESIDENT AND CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 473,334

Underlying: Common Stock · 473,334 shares

Expires 2031-03-10

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case, the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F3 · derivative.exercise_date: Immediately exercisable.

SEC source: 0001193125-25-297203 · ownership.xml · derivative · entry 4

Russo Rene · CIK 0001722066 · Director · PRESIDENT AND CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 473,334 shares

Expires 2031-03-10

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case, the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F3 · derivative.exercise_date: Immediately exercisable.

SEC source: 0001193125-25-297203 · ownership.xml · derivative · entry 3

Russo Rene · CIK 0001722066 · Director · PRESIDENT AND CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 239,703

Underlying: Common Stock · 239,703 shares

Expires 2030-07-22

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case, the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F3 · derivative.exercise_date: Immediately exercisable.

SEC source: 0001193125-25-297203 · ownership.xml · derivative · entry 2

Russo Rene · CIK 0001722066 · Director · PRESIDENT AND CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 239,703 shares

Expires 2030-07-22

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case, the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F3 · derivative.exercise_date: Immediately exercisable.

SEC source: 0001193125-25-297203 · ownership.xml · derivative · entry 1

Russo Rene · CIK 0001722066 · Director · PRESIDENT AND CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 2,075,000

Underlying: Common Stock · 2,075,000 shares

Expires 2035-10-07

F1 · date: On October 8, 2025, the Board of Directors (the "Board") approved the adoption of the Xilio Therapeutics, Inc. 2025 Stock Incentive Plan (the "2025 Plan"), subject to stockholder approval of the adoption of the 2025 Plan. On October 8, 2025, the Compensation Committee of the Board granted these options (referred to as "Tranche 1 Options" in the 2025 Plan) to the Reporting Person, subject to stockholder approval of the adoption of the 2025 Plan. The stockholders approved the adoption of the 2025 Plan on November 21, 2025.

F2 · derivative.exercise_date: The options vest in 36 equal monthly installments over the three-year period beginning on December 21, 2025, subject to the Reporting Person's continued service to the registrant through each applicable vesting date.

SEC source: 0001193125-25-297207 · ownership.xml · derivative · entry 7

Brennan Kevin M. · CIK 0001971303 · SVP, FINANCE AND ACCOUNTING

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 20,000

Underlying: Common Stock · 20,000 shares

Expires 2034-04-30

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.00 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F6 · derivative.exercise_date: This option was granted on May 1, 2024. The shares underlying the option began vesting on June 1, 2024 and continue to vest in equal monthly installments thereafter through May 1, 2028.

SEC source: 0001193125-25-297207 · ownership.xml · derivative · entry 6

Brennan Kevin M. · CIK 0001971303 · SVP, FINANCE AND ACCOUNTING

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 20,000 shares

Expires 2034-04-30

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.00 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F6 · derivative.exercise_date: This option was granted on May 1, 2024. The shares underlying the option began vesting on June 1, 2024 and continue to vest in equal monthly installments thereafter through May 1, 2028.

SEC source: 0001193125-25-297207 · ownership.xml · derivative · entry 5

Brennan Kevin M. · CIK 0001971303 · SVP, FINANCE AND ACCOUNTING

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 25,000

Underlying: Common Stock · 25,000 shares

Expires 2033-08-15

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.00 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F5 · derivative.exercise_date: Immediately exercisable.

SEC source: 0001193125-25-297207 · ownership.xml · derivative · entry 4

Brennan Kevin M. · CIK 0001971303 · SVP, FINANCE AND ACCOUNTING

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 25,000 shares

Expires 2033-08-15

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.00 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F5 · derivative.exercise_date: Immediately exercisable.

SEC source: 0001193125-25-297207 · ownership.xml · derivative · entry 3

Brennan Kevin M. · CIK 0001971303 · SVP, FINANCE AND ACCOUNTING

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 55,000

Underlying: Common Stock · 55,000 shares

Expires 2033-03-31

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.00 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F3 · derivative.exercise_date: This option was granted on April 1, 2023 and vested on March 30, 2024 with respect to 25% of the shares of common stock underlying the stock option. The remaining 75% of the shares of common stock underlying the stock option continues to vest in 36 equal monthly installments thereafter through March 30, 2027.

SEC source: 0001193125-25-297207 · ownership.xml · derivative · entry 2

Brennan Kevin M. · CIK 0001971303 · SVP, FINANCE AND ACCOUNTING

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 55,000 shares

Expires 2033-03-31

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.00 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F3 · derivative.exercise_date: This option was granted on April 1, 2023 and vested on March 30, 2024 with respect to 25% of the shares of common stock underlying the stock option. The remaining 75% of the shares of common stock underlying the stock option continues to vest in 36 equal monthly installments thereafter through March 30, 2027.

SEC source: 0001193125-25-297207 · ownership.xml · derivative · entry 1

Brennan Kevin M. · CIK 0001971303 · SVP, FINANCE AND ACCOUNTING

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 131,700

Underlying: Common Stock · 131,700 shares

Expires 2035-10-07

F1 · date: On October 8, 2025, the Board of Directors (the "Board") approved the adoption of the Xilio Therapeutics, Inc. 2025 Stock Incentive Plan (the "2025 Plan"), subject to stockholder approval of the adoption of the 2025 Plan. On October 8, 2025, the Compensation Committee of the Board granted these options (referred to as "Tranche 1 Options" in the 2025 Plan) to the Reporting Person, subject to stockholder approval of the adoption of the 2025 Plan. The stockholders approved the adoption of the 2025 Plan on November 21, 2025.

F2 · derivative.exercise_date: This option vests in 36 equal monthly installments over the three-year period beginning on December 21, 2025, subject to the Reporting Person's continued service to the registrant through each applicable vesting date.

SEC source: 0001193125-25-297204 · ownership.xml · derivative · entry 17

Frankenfield Christopher James · CIK 0001988344 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 300,000

Underlying: Common Stock · 300,000 shares

Expires 2033-08-15

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F3 · derivative.exercise_date: Immediately exercisable.

SEC source: 0001193125-25-297204 · ownership.xml · derivative · entry 16

Frankenfield Christopher James · CIK 0001988344 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 300,000 shares

Expires 2033-08-15

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F3 · derivative.exercise_date: Immediately exercisable.

SEC source: 0001193125-25-297204 · ownership.xml · derivative · entry 15

Frankenfield Christopher James · CIK 0001988344 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 150,000

Underlying: Common Stock · 150,000 shares

Expires 2033-08-02

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F8 · derivative.exercise_date: This option was granted on August 3, 2023. The shares underlying the option began vesting on September 1, 2023 and continue to vest in equal monthly installments thereafter through August 1, 2027.

SEC source: 0001193125-25-297204 · ownership.xml · derivative · entry 14

Frankenfield Christopher James · CIK 0001988344 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 150,000 shares

Expires 2033-08-02

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F8 · derivative.exercise_date: This option was granted on August 3, 2023. The shares underlying the option began vesting on September 1, 2023 and continue to vest in equal monthly installments thereafter through August 1, 2027.

SEC source: 0001193125-25-297204 · ownership.xml · derivative · entry 13

Frankenfield Christopher James · CIK 0001988344 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 117,000

Underlying: Common Stock · 117,000 shares

Expires 2032-12-31

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F7 · derivative.exercise_date: This option was granted on January 1, 2023. The shares underlying the option began vesting on February 1, 2023 and continue to vest in equal monthly installments thereafter through January 1, 2027.

SEC source: 0001193125-25-297204 · ownership.xml · derivative · entry 12

Frankenfield Christopher James · CIK 0001988344 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 117,000 shares

Expires 2032-12-31

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F7 · derivative.exercise_date: This option was granted on January 1, 2023. The shares underlying the option began vesting on February 1, 2023 and continue to vest in equal monthly installments thereafter through January 1, 2027.

SEC source: 0001193125-25-297204 · ownership.xml · derivative · entry 11

Frankenfield Christopher James · CIK 0001988344 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 20,000

Underlying: Common Stock · 20,000 shares

Expires 2032-08-31

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F6 · derivative.exercise_date: This option was granted on September 1, 2022. The shares underlying the option began vesting on September 1, 2022 and continue to vest in equal monthly installments thereafter through August 1, 2026.

SEC source: 0001193125-25-297204 · ownership.xml · derivative · entry 10

Frankenfield Christopher James · CIK 0001988344 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 20,000 shares

Expires 2032-08-31

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F6 · derivative.exercise_date: This option was granted on September 1, 2022. The shares underlying the option began vesting on September 1, 2022 and continue to vest in equal monthly installments thereafter through August 1, 2026.

SEC source: 0001193125-25-297204 · ownership.xml · derivative · entry 9

Frankenfield Christopher James · CIK 0001988344 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 45,000

Underlying: Common Stock · 45,000 shares

Expires 2032-02-21

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F5 · derivative.exercise_date: This option was granted on February 22, 2022. The shares underlying the option began vesting on March 1, 2022 and continue to vest in equal monthly installments thereafter through February 1, 2026.

SEC source: 0001193125-25-297204 · ownership.xml · derivative · entry 8

Frankenfield Christopher James · CIK 0001988344 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 45,000 shares

Expires 2032-02-21

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F5 · derivative.exercise_date: This option was granted on February 22, 2022. The shares underlying the option began vesting on March 1, 2022 and continue to vest in equal monthly installments thereafter through February 1, 2026.

SEC source: 0001193125-25-297204 · ownership.xml · derivative · entry 7

Frankenfield Christopher James · CIK 0001988344 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 37,296

Underlying: Common Stock · 37,296 shares

Expires 2031-10-20

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F3 · derivative.exercise_date: Immediately exercisable.

SEC source: 0001193125-25-297204 · ownership.xml · derivative · entry 6

Frankenfield Christopher James · CIK 0001988344 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 37,296 shares

Expires 2031-10-20

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F3 · derivative.exercise_date: Immediately exercisable.

SEC source: 0001193125-25-297204 · ownership.xml · derivative · entry 5

Frankenfield Christopher James · CIK 0001988344 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 23,786

Underlying: Common Stock · 23,786 shares

Expires 2031-03-31

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F3 · derivative.exercise_date: Immediately exercisable.

SEC source: 0001193125-25-297204 · ownership.xml · derivative · entry 4

Frankenfield Christopher James · CIK 0001988344 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 23,786 shares

Expires 2031-03-31

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F3 · derivative.exercise_date: Immediately exercisable.

SEC source: 0001193125-25-297204 · ownership.xml · derivative · entry 3

Frankenfield Christopher James · CIK 0001988344 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 155,090

Underlying: Common Stock · 155,090 shares

Expires 2031-03-28

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F3 · derivative.exercise_date: Immediately exercisable.

SEC source: 0001193125-25-297204 · ownership.xml · derivative · entry 2

Frankenfield Christopher James · CIK 0001988344 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 155,090 shares

Expires 2031-03-28

F4 · price: The transactions reported herein reflect a one-time option repricing, effective on November 21, 2025, which reduced the exercise price of each repriced option to $1.50 per share unless such repriced stock option is exercised prior to November 21, 2026, in which case the original exercise price must be paid (the "Option Repricing"). Except as modified by the Option Repricing, all other terms and conditions of the repriced options, including, without limitation, any provisions with respect to vesting and expiration, remain in full force and effect.

F3 · derivative.exercise_date: Immediately exercisable.

SEC source: 0001193125-25-297204 · ownership.xml · derivative · entry 1

Frankenfield Christopher James · CIK 0001988344 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 925,000

Underlying: Common Stock · 925,000 shares

Expires 2035-10-07

F1 · date: On October 8, 2025, the Board of Directors (the "Board") approved the adoption of the Xilio Therapeutics, Inc. 2025 Stock Incentive Plan (the "2025 Plan"), subject to stockholder approval of the adoption of the 2025 Plan. On October 8, 2025, the Compensation Committee of the Board granted these options (referred to as "Tranche 1 Options" in the 2025 Plan) to the Reporting Person, subject to stockholder approval of the adoption of the 2025 Plan. The stockholders approved the adoption of the 2025 Plan on November 21, 2025.

F2 · derivative.exercise_date: The options vest in 36 equal monthly installments over the three-year period beginning on December 21, 2025, subject to the Reporting Person's continued service to the registrant through each applicable vesting date.

SEC source: 0001415889-25-017705 · form4-06182025_080615.xml · nonDerivative · entry 2

Shannon James Samuel · CIK 0001485417 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 70,000

F2 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $0.6659 to $0.6991 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, 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.

SEC source: 0001415889-25-017705 · form4-06182025_080615.xml · nonDerivative · entry 1

Shannon James Samuel · CIK 0001485417 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 45,000

F1 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $0.6799 to $0.6891 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, 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.

SEC source: 0001415889-25-017704 · form4-06182025_080644.xml · nonDerivative · entry 1

Russo Rene · CIK 0001722066 · Director · PRESIDENT AND CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 281,172

F1 · price: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $0.6551 to $0.69 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, 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.

SEC source: 0001415889-25-016966 · form4-06122025_080613.xml · derivative · entry 1

Shannon James Samuel · CIK 0001485417 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 31,000

Underlying: Common Stock · 31,000 shares

Expires 2035-06-10

F1 · derivative.exercise_date: The option was granted on June 11, 2025 and will vest as to 100% of the shares underlying the option on the earlier of (i) June 11, 2026 and (ii) the Issuer's next annual meeting of stockholders following the grant date, subject to the Reporting Person's continued service to the Issuer through the vesting date.

SEC source: 0001415889-25-016968 · form4-06122025_080604.xml · derivative · entry 1

Clancy Paul J · CIK 0001409601 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 31,000

Underlying: Common Stock · 31,000 shares

Expires 2035-06-10

F1 · derivative.exercise_date: The option was granted on June 11, 2025 and will vest as to 100% of the shares underlying the option on the earlier of (i) June 11, 2026 and (ii) the Issuer's next annual meeting of stockholders following the grant date, subject to the Reporting Person's continued service to the Issuer through the vesting date.

SEC source: 0001415889-25-016970 · form4-06122025_080651.xml · derivative · entry 1

Bonstein Sara · CIK 0001604019 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 31,000

Underlying: Common Stock · 31,000 shares

Expires 2035-06-10

F1 · derivative.exercise_date: The option was granted on June 11, 2025 and will vest as to 100% of the shares underlying the option on the earlier of (i) June 11, 2026 and (ii) the Issuer's next annual meeting of stockholders following the grant date, subject to the Reporting Person's continued service to the Issuer through the vesting date.

SEC source: 0001415889-25-016971 · form4-06122025_080611.xml · derivative · entry 1

Brennan Aoife · CIK 0001714563 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 31,000

Underlying: Common Stock · 31,000 shares

Expires 2035-06-10

F1 · derivative.exercise_date: The option was granted on June 11, 2025 and will vest as to 100% of the shares underlying the option on the earlier of (i) June 11, 2026 and (ii) the Issuer's next annual meeting of stockholders following the grant date, subject to the Reporting Person's continued service to the Issuer through the vesting date.

SEC source: 0001415889-25-016972 · form4-06122025_080633.xml · derivative · entry 1

ROSS ROBERT W. · CIK 0001733077 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 31,000

Underlying: Common Stock · 31,000 shares

Expires 2035-06-10

F1 · derivative.exercise_date: The option was granted on June 11, 2025 and will vest as to 100% of the shares underlying the option on the earlier of (i) June 11, 2026 and (ii) the Issuer's next annual meeting of stockholders following the grant date, subject to the Reporting Person's continued service to the Issuer through the vesting date.

SEC source: 0001415889-25-016964 · form4-06122025_080649.xml · derivative · entry 1

Rossi Christina · CIK 0001756941 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 31,000

Underlying: Common Stock · 31,000 shares

Expires 2035-06-10

F1 · derivative.exercise_date: The option was granted on June 11, 2025 and will vest as to 100% of the shares underlying the option on the earlier of (i) June 11, 2026 and (ii) the Issuer's next annual meeting of stockholders following the grant date, subject to the Reporting Person's continued service to the Issuer through the vesting date.

SEC source: 0001415889-25-016969 · form4-06122025_080628.xml · derivative · entry 1

Curran Daniel J. · CIK 0001887599 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 31,000

Underlying: Common Stock · 31,000 shares

Expires 2035-06-10

F1 · derivative.exercise_date: The option was granted on June 11, 2025 and will vest as to 100% of the shares underlying the option on the earlier of (i) June 11, 2026 and (ii) the Issuer's next annual meeting of stockholders following the grant date, subject to the Reporting Person's continued service to the Issuer through the vesting date.

SEC source: 0001415889-25-016967 · form4-06122025_080636.xml · derivative · entry 1

Xu Yuan · CIK 0001858214 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 31,000

Underlying: Common Stock · 31,000 shares

Expires 2035-06-10

F1 · derivative.exercise_date: The option was granted on June 11, 2025 and will vest as to 100% of the shares underlying the option on the earlier of (i) June 11, 2026 and (ii) the Issuer's next annual meeting of stockholders following the grant date, subject to the Reporting Person's continued service to the Issuer through the vesting date.

SEC source: 0001415889-25-016962 · form4-06122025_080623.xml · derivative · entry 1

Bello Akintunde Olatokumbo · CIK 0002070709 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 62,000

Underlying: Common Stock · 62,000 shares

Expires 2035-06-09

F1 · derivative.exercise_date: The option was granted on June 10, 2025 and will vest in three equal installments on June 10, 2026, June 10, 2027 and June 10, 2028, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date.

SEC source: 0001062993-25-011170 · form4.xml · derivative · entry 4

GILEAD SCIENCES, INC. · CIK 0000882095 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 13,335,000

Underlying: Common Stock · 13,335,000 shares

Expires not disclosed

F1 · security: Each Prefunded Warrant was acquired together with an accompanying Series A Warrant, Series B Warrant and Series C Warrant at a combined offering price of $0.7499. A holder of any such warrant may not exercise such warrant if, after giving effect to such exercise, the holder and its affiliates would beneficially own, for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended, more than 19.99% of the outstanding shares of Common Stock of the Issuer (the "Common Stock").

F1 · price: Each Prefunded Warrant was acquired together with an accompanying Series A Warrant, Series B Warrant and Series C Warrant at a combined offering price of $0.7499. A holder of any such warrant may not exercise such warrant if, after giving effect to such exercise, the holder and its affiliates would beneficially own, for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended, more than 19.99% of the outstanding shares of Common Stock of the Issuer (the "Common Stock").

F5 · derivative.exercise_date: The Series C Warrants are exercisable at any time on or after June 1, 2026 and expire on the earlier of (i) December 2, 2026 and (ii) the expiration time of the Series B Warrants held by the reporting person to the extent that the corresponding Series B Warrants expire without being exercised, but with respect to only that number of Series C Warrants that is equal to the number of Series B Warrants that expire without being exercised. In addition, if the closing price of the Common Stock is below the exercise price on December 2, 2026, the exercise price will reset to the closing price on December 1, 2026 and the expiration time will be extended to December 31, 2026.

F5 · derivative.expiration_date: The Series C Warrants are exercisable at any time on or after June 1, 2026 and expire on the earlier of (i) December 2, 2026 and (ii) the expiration time of the Series B Warrants held by the reporting person to the extent that the corresponding Series B Warrants expire without being exercised, but with respect to only that number of Series C Warrants that is equal to the number of Series B Warrants that expire without being exercised. In addition, if the closing price of the Common Stock is below the exercise price on December 2, 2026, the exercise price will reset to the closing price on December 1, 2026 and the expiration time will be extended to December 31, 2026.

SEC source: 0001062993-25-011170 · form4.xml · derivative · entry 3

GILEAD SCIENCES, INC. · CIK 0000882095 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 13,335,000

Underlying: Common Stock · 13,335,000 shares

Expires not disclosed

F1 · security: Each Prefunded Warrant was acquired together with an accompanying Series A Warrant, Series B Warrant and Series C Warrant at a combined offering price of $0.7499. A holder of any such warrant may not exercise such warrant if, after giving effect to such exercise, the holder and its affiliates would beneficially own, for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended, more than 19.99% of the outstanding shares of Common Stock of the Issuer (the "Common Stock").

F1 · price: Each Prefunded Warrant was acquired together with an accompanying Series A Warrant, Series B Warrant and Series C Warrant at a combined offering price of $0.7499. A holder of any such warrant may not exercise such warrant if, after giving effect to such exercise, the holder and its affiliates would beneficially own, for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended, more than 19.99% of the outstanding shares of Common Stock of the Issuer (the "Common Stock").

F4 · derivative.exercise_date: The Series B Warrants are exercisable at any time on or after November 1, 2025 and expire on December 2, 2025, provided that if the closing price of the Common Stock is below the exercise price on such date, the exercise price will reset to the closing price on December 1, 2025 and the expiration time will be extended to December 31, 2025.

F4 · derivative.expiration_date: The Series B Warrants are exercisable at any time on or after November 1, 2025 and expire on December 2, 2025, provided that if the closing price of the Common Stock is below the exercise price on such date, the exercise price will reset to the closing price on December 1, 2025 and the expiration time will be extended to December 31, 2025.

SEC source: 0001062993-25-011170 · form4.xml · derivative · entry 2

GILEAD SCIENCES, INC. · CIK 0000882095 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 13,335,000

Underlying: Common Stock · 13,335,000 shares

Expires not disclosed

F1 · security: Each Prefunded Warrant was acquired together with an accompanying Series A Warrant, Series B Warrant and Series C Warrant at a combined offering price of $0.7499. A holder of any such warrant may not exercise such warrant if, after giving effect to such exercise, the holder and its affiliates would beneficially own, for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended, more than 19.99% of the outstanding shares of Common Stock of the Issuer (the "Common Stock").

F1 · price: Each Prefunded Warrant was acquired together with an accompanying Series A Warrant, Series B Warrant and Series C Warrant at a combined offering price of $0.7499. A holder of any such warrant may not exercise such warrant if, after giving effect to such exercise, the holder and its affiliates would beneficially own, for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended, more than 19.99% of the outstanding shares of Common Stock of the Issuer (the "Common Stock").

F3 · derivative.exercise_date: The Series A Warrants will be exercisable at any time on or after the earlier of (i) December 1, 2025 and (ii) the trading day immediately following a period of five consecutive trading days on which the closing price of the Common Stock is a minimum of $1.50 per share and will expire on the earlier of (A) June 5, 2030 and (B) immediately upon exercise of the reporting person's Prefunded Warrants issued on June 5, 2025 if such exercise is prior to December 1, 2025, but with respect to only that number of Series A Warrants that is equal to the number of Prefunded Warrants that are exercised.

F3 · derivative.expiration_date: The Series A Warrants will be exercisable at any time on or after the earlier of (i) December 1, 2025 and (ii) the trading day immediately following a period of five consecutive trading days on which the closing price of the Common Stock is a minimum of $1.50 per share and will expire on the earlier of (A) June 5, 2030 and (B) immediately upon exercise of the reporting person's Prefunded Warrants issued on June 5, 2025 if such exercise is prior to December 1, 2025, but with respect to only that number of Series A Warrants that is equal to the number of Prefunded Warrants that are exercised.

SEC source: 0001062993-25-011170 · form4.xml · derivative · entry 1

GILEAD SCIENCES, INC. · CIK 0000882095 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 23,310,266

Underlying: Common Stock · 13,335,000 shares

Expires not disclosed

F1 · security: Each Prefunded Warrant was acquired together with an accompanying Series A Warrant, Series B Warrant and Series C Warrant at a combined offering price of $0.7499. A holder of any such warrant may not exercise such warrant if, after giving effect to such exercise, the holder and its affiliates would beneficially own, for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended, more than 19.99% of the outstanding shares of Common Stock of the Issuer (the "Common Stock").

F1 · price: Each Prefunded Warrant was acquired together with an accompanying Series A Warrant, Series B Warrant and Series C Warrant at a combined offering price of $0.7499. A holder of any such warrant may not exercise such warrant if, after giving effect to such exercise, the holder and its affiliates would beneficially own, for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended, more than 19.99% of the outstanding shares of Common Stock of the Issuer (the "Common Stock").

F2 · derivative.exercise_date: The Prefunded Warrants are exercisable at any time on or after the date of issuance and have no expiration date.

F2 · derivative.expiration_date: The Prefunded Warrants are exercisable at any time on or after the date of issuance and have no expiration date.

SEC source: 0001415889-25-010805 · form4-04162025_040405.xml · derivative · entry 1

Russo Rene · CIK 0001722066 · Director · PRESIDENT AND CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 190,000

Underlying: Common Stock · 190,000 shares

Expires 2035-04-14

F1 · derivative.exercise_date: The option was granted on April 15, 2025 and will vest in equal monthly installments beginning on May 1, 2025 through April 1, 2029.

SEC source: 0001415889-25-010804 · form4-04162025_040404.xml · derivative · entry 1

Frankenfield Christopher James · CIK 0001988344 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 75,000

Underlying: Common Stock · 75,000 shares

Expires 2035-04-14

F1 · derivative.exercise_date: The option was granted on April 15, 2025 and will vest in equal monthly installments beginning on May 1, 2025 through April 1, 2029.

SEC source: 0001415889-25-000407 · form4-01032025_040116.xml · nonDerivative · entry 2

Frankenfield Christopher James · CIK 0001988344 · Chief Financial Officer

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 12,421

F2 · kind: The reported sale of 6,954 shares occurred automatically in a "sell to cover" transaction pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on April 8, 2024 solely to cover tax withholding obligations in connection with the vesting of restricted stock units.

SEC source: 0001415889-25-000404 · form4-01032025_040109.xml · nonDerivative · entry 2

Brennan Kevin M. · CIK 0001971303 · SVP, FINANCE AND ACCOUNTING

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 3,197

F2 · kind: The reported sale of 1,803 shares occurred automatically in a "sell to cover" transaction pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on April 8, 2024 solely to cover tax withholding obligations in connection with the vesting of restricted stock units.

SEC source: 0001415889-25-000406 · form4-01032025_040113.xml · derivative · entry 3

Luptakova Katarina · CIK 0001991149 · CHIEF MEDICAL OFFICER

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 200,000

Underlying: Common Stock · 200,000 shares

Expires 2035-12-31

F3 · derivative.exercise_date: The option was granted on January 1, 2025 and will vest in 48 equal monthly installments beginning on February 1, 2025 and continuing through January 1, 2029.