PYXS · Pyxis Oncology, Inc.

The shares subject to this option will vest in equal monthly installments through October 31, 2026, subject to the reporting person's continued service through the applicable vesting date.

Represents the performance-based portion of an option that was granted on February 3, 2026, which shares subject to this portion of the option were to become vested in full upon the completion of a successful financing transaction or a successful strategic transaction during the reporting person's continued service as Interim Chief Executive Officer or within six months thereafter. The performance conditions were deemed to have been met on August 12, 2026, as determined by the Board.

Award of stock options to purchase Common Shares with a vesting commencement date of August 23, 2024. These options vest and become exercisable in three equal annual tranches from August 23, 2023, subject generally to the reporting person's continuous service through each vesting date (unless otherwise provided in the applicable award documentation).

The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on Septemeber 24, 2025.

Reflects sales of common stock executed in multiple transactions. The price reported reflects the weighted average sale price. The Reporting Person hereby undertakes to provide upon request by the Securities and Exchange Commission staff, the Issuer or a security holder of the Issuer full information regarding the number of shares and prices at which the sales were effected within the ranges set forth in footnotes 3 of this Form 4.

The transaction was executed in multiple trades in prices ranging from $3.00 to $3.36.

The shares subject to this option will vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

The shares subject to this option will vest over four years, with 25% vesting on the first anniversary of March 24, 2026 and the remainder vesting in 36 equal monthly installments thereafter, subject to the reporting person's continued emmployment through the applicable vesting date.

Represents restricted stock units that vest 25% on March 31, 2026, and then in 36 substantially-equal monthly installments thereafter, subject to the reporting person's continued employment through the applicable vesting date.

The shares subject to this option will vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

The shares subject to this option will vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

The shares subject to this option will vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

The shares subject to this option will vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

The shares subject to this option will vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

The shares subject to this option will vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

The shares subject to this option will vest in 12 equal monthly installments, commencing on the grant date and subject to the reporting person's continued service as Interim Chief Executive Officer through the applicable vesting date.

The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on December 5, 2024.

Reflects sales of common stock executed in multiple transactions. The price reported reflects the weighted average sale price. The Reporting Person hereby undertakes to provide upon request by the Securities and Exchange Commission staff, the Issuer or a security holder of the Issuer full information regarding the number of shares and prices at which the sales were effected within the ranges set forth in footnotes 3 through 4 of this Form 4.

The transaction was executed in multiple trades in prices ranging from $0.97 to $1.09.

The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on December 5, 2024.

The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on December 5, 2024.

Reflects sales of common stock executed in multiple transactions. The price reported reflects the weighted average sale price. The Reporting Person hereby undertakes to provide upon request by the Securities and Exchange Commission staff, the Issuer or a security holder of the Issuer full information regarding the number of shares and prices at which the sales were effected within the ranges set forth in footnotes 3 through 4 of this Form 4.

The transaction was executed in multiple trades in prices ranging from $0.97 to $0.98.

The shares subject to this option will vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

The shares subject to this option will vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

The shares subject to this option will vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

The shares subject to this option will vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

The shares subject to this option will vest over four years, with 25% vesting on the first anniversary of March 31,2025 and the remainder vesting in 36 equal monthly instalments thereafter subject to the reporting person's continued employment through the applicable vesting date.

The shares subject to this option will vest over four years, with 25% vesting on the first anniversary of March 31, 2025 and the remainder vesting in 36 equal monthly installments thereafter subject to the reporting person's continued emmployment through the applicable vesting date.

The shares subject to this option will vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

The shares subject to this option will vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

The shares subject to this option will vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

The shares subject to this option will vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

The shares subject to this option will vest over four years, with 25% vesting on the first anniversary of March 31,2025 and the remainder vesting in 36 equal monthly instalments thereafter subject to the reporting person's continued employment through the applicable vesting date.

The shares subject to this option vest in full on December 23, 2025, subject to the Reporting Person's continued employment through the vesting date.

The shares subject to this option vest in full on December 23, 2025, subject to the Reporting Person's continued employment through the vesting date.

The shares subject to this option vest in full on December 23, 2025, subject to the Reporting Person's continued employment through the vesting date.

These shares are held directly by the Personal Def Ben Pln Trust, a revocable trust for which the Reporting Person and their spouse are the trustees.

The price reported in column 4 is a weighted-average price.These shares were purchased in multiple transactions at prices ranging from $1.93 to $1.99, 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 herein.

The shares subject to this option shall vest in three equal annual installments beginning on the first anniversary of June 10, 2024, subject to the reporting person's continued service through the applicable vesting date.

Represents restricted stock units that vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

The shares subject to this option will vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

Represents restricted stock units that vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

Represents restricted stock units that vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

Represents restricted stock units that vest 25% on the first anniversary of March 26, 2024, and then in 36 substantially-equal monthly installments thereafter, subject to the reporting person's continued employment through the applicable vesting date.

The shares subject to this option will vest over four years, with 25% vesting on the first anniversary of March 26, 2024 and the remainder vesting in 36 equal monthly installments thereafter, subject to the reporting person's continued employment through the applicable vesting date.

Represents restricted stock units that vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

Represents restricted stock units that vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

Represents restricted stock units that vest 100% on the first anniversary of the grant date, subject to the reporting person's continued service through the applicable vesting date.

Represents restricted stock units that vest 25% on the first anniversary of March 26, 2024, and then in 36 substantially-equal monthly installments thereafter, subject to the reporting person's continued employment through the applicable vesting date.

The shares subject to this option shall vest in three equal annual installments beginning on the first anniversary of March 12, 2024, subject to the reporting person's continued service through the applicable vesting date.

The shares subject to this option will vest over four years, with 25% vesting on November 27, 2024 and the remainder vesting in 36 equal monthly installments thereafter, subject to the Reporting Person's continued employment through the applicable vesting dates.

The shares subject to this option will vest upon the achievement of certain clinical milestones related to data disclosure for PYX-201.

Represents shares withheld to cover taxes due upon the vesting of certain restricted stock units.

Represents restricted stock units that vest in full on November 14, 2024, subject to the Reporting Person's continued employment through the vesting date.