ATRA · Atara Biotherapeutics, Inc. · Insider Trading

Represents shares purchased by the Reporting Person from the Issuer, through its sales agent, pursuant to that certain Sales Agreement, dated November 1, 2023, by and between the Issuer and TD Securities (USA) LLC.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on August 17, 2026, on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

On July 22, 2026, the Reporting Persons exercised the reported Pre-Funded Warrants through a "cashless exercise" resulting in the Issuer withholding 60 shares of Common Stock to pay the exercise price and issuing the remaining 195,151 shares of Common Stock to the applicable Funds. The number of shares withheld to pay the aggregate exercise price for the cashless exercise of the Pre-Funded Warrants was based on the closing sale price per share of the Common Stock on the trading date immediately prior to the exercise date, per the terms of the Pre-Funded Warrants.

The reported securities are directly owned by certain private funds managed by Redmile Group, LLC (collectively, the "Funds") and may be deemed beneficially owned by Redmile Group, LLC ("Redmile") as investment manager of the Funds. The reported securities may also be deemed beneficially owned by Jeremy Green as the principal of Redmile. Each of Redmile and Mr. Green (the "Reporting Persons") disclaims beneficial ownership of the reported securities except to the extent of their pecuniary interest therein, if any. This report shall not be deemed an admission that such Reporting Persons are the beneficial owners of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.

The Pre-Funded Warrants are exercisable at any time on or after the original issuance on December 11, 2020 until the seven-year anniversary of the original issuance date, at an exercise price equal to $0.0025 per share, subject to a 9.99% beneficial ownership blocker.

The previous report on Form 3 inadvertently indicated that all of the Pre-Funded Warrants beneficially owned by the Reporting Persons have an exercise price of $0.0001 per share and no expiration date. Footnotes (1), (2), (3), (6) and (7) and the related disclosures correct the Form 3 with respect to the terms of the Pre-Funded Warrants beneficially owned by the Reporting Persons.

On July 22, 2026, the Reporting Persons exercised the reported Pre-Funded Warrants through a "cashless exercise" resulting in the Issuer withholding 60 shares of Common Stock to pay the exercise price and issuing the remaining 195,151 shares of Common Stock to the applicable Funds. The number of shares withheld to pay the aggregate exercise price for the cashless exercise of the Pre-Funded Warrants was based on the closing sale price per share of the Common Stock on the trading date immediately prior to the exercise date, per the terms of the Pre-Funded Warrants.

The reported securities are directly owned by certain private funds managed by Redmile Group, LLC (collectively, the "Funds") and may be deemed beneficially owned by Redmile Group, LLC ("Redmile") as investment manager of the Funds. The reported securities may also be deemed beneficially owned by Jeremy Green as the principal of Redmile. Each of Redmile and Mr. Green (the "Reporting Persons") disclaims beneficial ownership of the reported securities except to the extent of their pecuniary interest therein, if any. This report shall not be deemed an admission that such Reporting Persons are the beneficial owners of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.

The Pre-Funded Warrants are exercisable at any time on or after the original issuance on July 23, 2019 until the seven-year anniversary of the original issuance date, at an exercise price equal to $0.0025 per share, subject to a 9.99% beneficial ownership blocker.

The previous report on Form 3 inadvertently indicated that all of the Pre-Funded Warrants beneficially owned by the Reporting Persons have an exercise price of $0.0001 per share and no expiration date. Footnotes (1), (2), (3), (6) and (7) and the related disclosures correct the Form 3 with respect to the terms of the Pre-Funded Warrants beneficially owned by the Reporting Persons.

On July 22, 2026, the Reporting Persons exercised the reported Pre-Funded Warrants through a "cashless exercise" resulting in the Issuer withholding 60 shares of Common Stock to pay the exercise price and issuing the remaining 195,151 shares of Common Stock to the applicable Funds. The number of shares withheld to pay the aggregate exercise price for the cashless exercise of the Pre-Funded Warrants was based on the closing sale price per share of the Common Stock on the trading date immediately prior to the exercise date, per the terms of the Pre-Funded Warrants.

The reported securities are directly owned by certain private funds managed by Redmile Group, LLC (collectively, the "Funds") and may be deemed beneficially owned by Redmile Group, LLC ("Redmile") as investment manager of the Funds. The reported securities may also be deemed beneficially owned by Jeremy Green as the principal of Redmile. Each of Redmile and Mr. Green (the "Reporting Persons") disclaims beneficial ownership of the reported securities except to the extent of their pecuniary interest therein, if any. This report shall not be deemed an admission that such Reporting Persons are the beneficial owners of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.

The Pre-Funded Warrants are exercisable at any time on or after the original issuance on May 29, 2020 until the seven-year anniversary of the original issuance date, at an exercise price equal to $0.0025 per share, subject to a 9.99% beneficial ownership blocker.

The previous report on Form 3 inadvertently indicated that all of the Pre-Funded Warrants beneficially owned by the Reporting Persons have an exercise price of $0.0001 per share and no expiration date. Footnotes (1), (2), (3), (6) and (7) and the related disclosures correct the Form 3 with respect to the terms of the Pre-Funded Warrants beneficially owned by the Reporting Persons.

On July 22, 2026, the Reporting Persons exercised the reported Pre-Funded Warrants through a "cashless exercise" resulting in the Issuer withholding 60 shares of Common Stock to pay the exercise price and issuing the remaining 195,151 shares of Common Stock to the applicable Funds. The number of shares withheld to pay the aggregate exercise price for the cashless exercise of the Pre-Funded Warrants was based on the closing sale price per share of the Common Stock on the trading date immediately prior to the exercise date, per the terms of the Pre-Funded Warrants.

The reported securities are directly owned by certain private funds managed by Redmile Group, LLC (collectively, the "Funds") and may be deemed beneficially owned by Redmile Group, LLC ("Redmile") as investment manager of the Funds. The reported securities may also be deemed beneficially owned by Jeremy Green as the principal of Redmile. Each of Redmile and Mr. Green (the "Reporting Persons") disclaims beneficial ownership of the reported securities except to the extent of their pecuniary interest therein, if any. This report shall not be deemed an admission that such Reporting Persons are the beneficial owners of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.

On July 22, 2026, the Reporting Persons exercised the reported Pre-Funded Warrants through a "cashless exercise" resulting in the Issuer withholding 60 shares of Common Stock to pay the exercise price and issuing the remaining 195,151 shares of Common Stock to the applicable Funds. The number of shares withheld to pay the aggregate exercise price for the cashless exercise of the Pre-Funded Warrants was based on the closing sale price per share of the Common Stock on the trading date immediately prior to the exercise date, per the terms of the Pre-Funded Warrants.

The reported securities are directly owned by certain private funds managed by Redmile Group, LLC (collectively, the "Funds") and may be deemed beneficially owned by Redmile Group, LLC ("Redmile") as investment manager of the Funds. The reported securities may also be deemed beneficially owned by Jeremy Green as the principal of Redmile. Each of Redmile and Mr. Green (the "Reporting Persons") disclaims beneficial ownership of the reported securities except to the extent of their pecuniary interest therein, if any. This report shall not be deemed an admission that such Reporting Persons are the beneficial owners of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.

These restricted stock units shall vest as to 1/3 of the shares on the first, second and third anniversaries of June 11, 2026, subject to the Reporting Person's continuous service.

These restricted stock units shall vest on the earlier of June 9, 2027 or the date of the next annual meeting of stockholders, subject to the Reporting Person's continuous service.

These restricted stock units shall vest on the earlier of June 9, 2027 or the date of the next annual meeting of stockholders, subject to the Reporting Person's continuous service.

These restricted stock units shall vest on the earlier of June 9, 2027 or the date of the next annual meeting of stockholders, subject to the Reporting Person's continuous service.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

Represents the weighted average price. The shares were sold in multiple transactions at prices ranging from $9.12 to $9.40, inclusive. The Reporting Person undertakes to provide to the Issuer, any securityholder of the Issuer, 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 above.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

Represents the weighted average price. The shares were sold in multiple transactions at prices ranging from $9.12 to $9.40, inclusive. The Reporting Person undertakes to provide to the Issuer, any securityholder of the Issuer, 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 above.

The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions ranging from $10.00 to $10.50, inclusive. The Reporting Person undertake to provide to the Issuer, any securityholder of the Issuer, 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 above.

Represents securities held by Panacea Venture Healthcare Fund II, L.P.

James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. ("Fund II GP") and Panacea Opportunity Fund I GP Company, Ltd. ("Opportunity Fund GP"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership.

Qualified Fund purchased 474,780 of the shares puchased in this transaction.

The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $8.85 to $9.39 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 ranges set forth in this footnote.

After this transaction, Qualified Fund held 1,445,609 shares of the Issuer's Common Stock.

The reporting persons are EcoR1 Capital, LLC ("EcoR1"), Oleg Nodelman and EcoR1 Capital Fund Qualified, L.P. ("Qualified Fund"). EcoR1 is the general partner and investment adviser of private funds, including Qualified Fund (the "Funds"). Mr. Nodelman is the manager and controller owner of EcoR1. EcoR1 is filing this Form 4 for itself, Mr. Nodelman and Qualified Fund. The reporting persons are filing this Form 4 jointly, but not as a group, and each expressly disclaims membership in a group within the meaning of Rule 13d-5(b) under the Securities Exchange Act of 1934. The Funds hold these securities directly for the benefit of their investors. EcoR1 may be deemed to indirectly beneficially own them as the investment adviser to the Funds. Mr. Nodelman may be deemed to indirectly beneficially own them as the control person of EcoR1. The reporting persons disclaim beneficial ownership of the securities except to the extent of their respective pecuniary interests therein.

The warrants are immediately exercisable and do not expire. Pursuant to the terms of the warrants, no portion of the warrants held by a holder may be exercised to the extent that, after giving effect to the attempted exercise, such holder, together with such holder's affiliates and any other person whose beneficial ownership of the Issuer's common stock would be aggregated with such holder's for the purposes of Section 13(d) of the Exchange Act, would beneficially own in excess of 19.99% of the outstanding common stock.

Represents securities held by Panacea Opportunity Fund I, L.P.

James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. ("Fund II GP") and Panacea Opportunity Fund I GP Company, Ltd. ("Opportunity Fund GP"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership.

Represents securities held by Panacea Opportunity Fund I, L.P.

James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. ("Fund II GP") and Panacea Opportunity Fund I GP Company, Ltd. ("Opportunity Fund GP"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership.

Represents securities held by Panacea Opportunity Fund I, L.P.

James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. ("Fund II GP") and Panacea Opportunity Fund I GP Company, Ltd. ("Opportunity Fund GP"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership.

These restricted stock units ("RSUs") vest as to 1/8th of the total number of shares (rounded down to the next whole number of shares) on the second Quarterly Vesting Date (as defined below) following March 9, 2026, and as to 1/8th of the total number of shares (rounded down to the next whole number of shares) on the next seven Quarterly Vesting Dates, such that all of the shares subject to the RSUs shall be vested on the last Quarterly Vesting Date, subject to the reporting person's continuous employment. "Quarterly Vesting Date" means March 1, May 15, August 15, and November 15 of each year, provided that if such date falls on a weekend or holiday, the Quarterly Vesting Date shall be the first business day after such date.

These restricted stock units ("RSUs") vest as to 1/8th of the total number of shares (rounded down to the next whole number of shares) on the second Quarterly Vesting Date (as defined below) following March 9, 2026, and as to 1/8th of the total number of shares (rounded down to the next whole number of shares) on the next seven Quarterly Vesting Dates, such that all of the shares subject to the RSUs shall be vested on the last Quarterly Vesting Date, subject to the reporting person's continuous employment. "Quarterly Vesting Date" means March 1, May 15, August 15, and November 15 of each year, provided that if such date falls on a weekend or holiday, the Quarterly Vesting Date shall be the first business day after such date.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on March 2, 2026 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on March 2, 2026 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on March 2, 2026 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on March 2, 2026 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on March 2, 2026 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on March 2, 2026 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

This amount includes 400 shares purchased under the Issuer's Employee Stock Purchase Plan on November 28, 2025.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on March 2, 2026 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on March 2, 2026 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions ranging from $5.9888 to $6.2838, inclusive. The Reporting Person undertake to provide to the Issuer, any securityholder of the Issuer, 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 above.

Represents securities held by Panacea Venture Healthcare Fund II, L.P.

James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. ("Fund II GP") and Panacea Opportunity Fund I GP Company, Ltd. ("Opportunity Fund GP"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership.

Represents securities held by Panacea Opportunity Fund I, L.P.

James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. ("Fund II GP") and Panacea Opportunity Fund I GP Company, Ltd. ("Opportunity Fund GP"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership.

The warrants are immediately exercisable and do not expire. Pursuant to the terms of the warrants, no portion of the warrants held by a holder may be exercised to the extent that, after giving effect to the attempted exercise, such holder, together with such holder's affiliates and any other person whose beneficial ownership of the Issuer's common stock would be aggregated with such holder's for the purposes of Section 13(d) of the Exchange Act, would beneficially own in excess of 19.99% of the outstanding common stock.

Represents securities held by Panacea Opportunity Fund I, L.P.

James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. ("Fund II GP") and Panacea Opportunity Fund I GP Company, Ltd. ("Opportunity Fund GP"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership.

Represents securities held by Panacea Opportunity Fund I, L.P.

James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. ("Fund II GP") and Panacea Opportunity Fund I GP Company, Ltd. ("Opportunity Fund GP"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on November 17, 2025 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on November 17, 2025 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on November 17, 2025 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on November 17, 2025 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on November 17, 2025 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on August 18, 2025 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on August 18, 2025 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on August 18, 2025 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on August 18, 2025 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on August 18, 2025 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

Shares sold automatically to satisfy tax withholding obligations in connection with the vesting of previously granted restricted stock units, pursuant to a sale-to-cover provision in the award agreement.

The sale price of the reporting person's shares represents the weighted average price of all shares sold by a broker on August 18, 2025 on behalf of a group of employees of the Issuer to satisfy the payment of withholding tax liability of such employees.

The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions ranging from $11.83 to $12.44, inclusive. The Reporting Person undertake to provide to the Issuer, any securityholder 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 above.

Represents securities held by Panacea Venture Healthcare Fund II, L.P.

James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. ("Fund II GP") and Panacea Opportunity Fund I GP Company, Ltd. ("Opportunity Fund GP"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership.

Represents securities held by Panacea Venture Healthcare Fund II, L.P.

James Huang is the sole owner of Panacea Innovation Limited, which is the sole owner of Panacea Venture Healthcare Fund II GP Company, Ltd. ("Fund II GP") and Panacea Opportunity Fund I GP Company, Ltd. ("Opportunity Fund GP"), which are the general partners of Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P. As a result, each of the Reporting Persons may be deemed to share beneficial ownership of the securities held of record by Panacea Venture Healthcare Fund II, L.P. and Panacea Opportunity Fund I, L.P., but each disclaims such beneficial ownership.

These restricted stock units shall vest on the earlier of June 10, 2026 or the date of the next annual meeting of stockholders, subject to the Reporting Person's continuous service.

This amount reflects the 1:25 reverse stock split effected by the Issuer on June 20, 2024.

These restricted stock units shall vest on the earlier of June 10, 2026 or the date of the next annual meeting of stockholders, subject to the Reporting Person's continuous service.

These restricted stock units shall vest on the earlier of June 10, 2026 or the date of the next annual meeting of stockholders, subject to the Reporting Person's continuous service.

This amount reflects the 1:25 reverse stock split effected by the Issuer on June 20, 2024.

These restricted stock units shall vest on the earlier of June 10, 2026 or the date of the next annual meeting of stockholders, subject to the Reporting Person's continuous service.

This amount reflects the 1:25 reverse stock split effected by the Issuer on June 20, 2024.

These restricted stock units shall vest on the earlier of June 10, 2026 or the date of the next annual meeting of stockholders, subject to the Reporting Person's continuous service.

This amount reflects the 1:25 reverse stock split effected by the Issuer on June 20, 2024.