REPL · Replimune Group, Inc.

The sales reported on this Form 4 were made by the Reporting Person pursuant to a trading plan adopted on December 15, 2025, that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

The price reported reflects a weighted average price of the Shares. The Shares were sold in multiple transactions at prices ranging from $9.15 to $9.62 per Share. The Reporting Person will provide to the Issuer, any security holder of the Issuer or the Securities Exchange Commission staff, upon request, information regarding the number of Shares sold at each price within the range.

Represents shares of the Issuer's common stock (the "Shares") sold to cover tax withholding obligations in connection with the partial vesting of the Reporting Person's Restricted Stock Units ("RSU"). The transaction reported herein was made in accordance with the irrevocable "sell to cover" provision set forth in the award agreements under which the RSUs were granted and does not represent a discretionary sale by the Reporting Person.

The price reported reflects a weighted average price of the Shares. The Shares were sold in multiple transactions at prices ranging from $5.01 to $5.08 per Share. The Reporting Person will provide to the Issuer, any security holder of the Issuer or the Securities Exchange Commission staff, upon request, information regarding the number of Shares sold at each price within the range.

Represents shares of the Issuer's common stock (the "Shares") sold to cover tax withholding obligations in connection with the partial vesting of the Reporting Person's Restricted Stock Units ("RSU"). The transaction reported herein was made in accordance with the irrevocable "sell to cover" provision set forth in the award agreements under which the RSUs were granted and does not represent a discretionary sale by the Reporting Person.

The price reported reflects a weighted average price of the Shares. The Shares were sold in multiple transactions at prices ranging from $5.01 to $5.08 per Share. The Reporting Person will provide to the Issuer, any security holder of the Issuer or the Securities Exchange Commission staff, upon request, information regarding the number of Shares sold at each price within the range.

Represents shares of the Issuer's common stock (the "Shares") sold to cover tax withholding obligations in connection with the partial vesting of the Reporting Person's Restricted Stock Units ("RSU"). The transaction reported herein was made in accordance with the irrevocable "sell to cover" provision set forth in the award agreements under which the RSUs were granted and does not represent a discretionary sale by the Reporting Person.

The price reported reflects a weighted average price of the Shares. The Shares were sold in multiple transactions at prices ranging from $5.02 to $5.08 per Share. The Reporting Person will provide to the Issuer, any security holder of the Issuer or the Securities Exchange Commission staff, upon request, information regarding the number of Shares sold at each price within the range.

Represents shares of the Issuer's common stock (the "Shares") sold to cover tax withholding obligations in connection with the partial vesting of the Reporting Person's Restricted Stock Units ("RSU"). The transaction reported herein was made in accordance with the irrevocable "sell to cover" provision set forth in the award agreements under which the RSUs were granted and does not represent a discretionary sale by the Reporting Person.

The price reported reflects a weighted average price of the Shares. The Shares were sold in multiple transactions at prices ranging from $5.01 to $5.08 per Share. The Reporting Person will provide to the Issuer, any security holder of the Issuer or the Securities Exchange Commission staff, upon request, information regarding the number of Shares sold at each price within the range.

Represents shares of the Issuer's common stock (the "Shares") sold to cover tax withholding obligations in connection with the partial vesting of the Reporting Person's Restricted Stock Units ("RSU"). The transaction reported herein was made in accordance with the irrevocable "sell to cover" provision set forth in the award agreements under which the RSUs were granted and does not represent a discretionary sale by the Reporting Person.

The price reported reflects a weighted average price of the Shares. The Shares were sold in multiple transactions at prices ranging from $5.01 to $5.08 per Share. The Reporting Person will provide to the Issuer, any security holder of the Issuer or the Securities Exchange Commission staff, upon request, information regarding the number of Shares sold at each price within the range.

Represents shares of the Issuer's common stock (the "Shares") sold to cover tax withholding obligations in connection with the partial vesting of the Reporting Person's Restricted Stock Units ("RSU"). The transaction reported herein was made in accordance with the irrevocable "sell to cover" provision set forth in the award agreements under which the RSUs were granted and does not represent a discretionary sale by the Reporting Person.

The price reported reflects a weighted average price of the Shares. The Shares were sold in multiple transactions at prices ranging from $5.02 to $5.08 per Share. The Reporting Person will provide to the Issuer, any security holder of the Issuer or the Securities Exchange Commission staff, upon request, information regarding the number of Shares sold at each price within the range.

The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on December 15, 2025, that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

The price reported reflects a weighted average price. These shares were sold in multiple transactions at prices ranging from $8.00 to $8.06. The reporting person will provide to the Issuer, any security holder of the Issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.

Following the sales reported on this Form 4, the reporting person continues to beneficially own 151,588 shares of the Issuer's common stock, including restricted stock units. The reporting person also holds options to acquire an aggregate of 250,425 shares of the Issuer's common stock, 142,555 of which are exercisable as of the date hereof.

The shares underlying this option vest entirely on April 1, 2027.

25% of the shares underlying this stock option vest on April 1, 2027, and the remainder of the shares underlying this stock option vest in 36 approximately equal monthly installments thereafter.

The shares underlying this option vest entirely on April 1, 2027.

Represents shares of the Issuer's common stock issuable upon settlement of restricted stock units ("RSUs") granted to the Reporting Person. Each RSU represents a contingent right to receive one share of the Issuer's common stock. 25% of the RSUs will vest on May 15, 2027 and the remainder will vest in three approximately equal annual installments thereafter until May 15, 2030, subject to the Reporting Person's continuous service to the Issuer.

25% of the shares underlying this stock option vest on April 1, 2027, and the remainder of the shares underlying this stock option vest in 36 approximately equal monthly installments thereafter.

Represents shares of the Issuer's common stock issuable upon settlement of restricted stock units ("RSUs") granted to the Reporting Person. Each RSU represents a contingent right to receive one share of the Issuer's common stock. 25% of the RSUs will vest on May 15, 2027 and the remainder will vest in three approximately equal annual installments thereafter until May 15, 2030, subject to the Reporting Person's continuous service to the Issuer.

25% of the shares underlying this stock option vest on April 1, 2027, and the remainder of the shares underlying this stock option vest in 36 approximately equal monthly installments thereafter.

Represents shares of the Issuer's common stock issuable upon settlement of restricted stock units ("RSUs") granted to the Reporting Person. Each RSU represents a contingent right to receive one share of the Issuer's common stock. 25% of the RSUs will vest on May 15, 2027 and the remainder will vest in three approximately equal annual installments thereafter until May 15, 2030, subject to the Reporting Person's continuous service to the Issuer.

Represents shares of the Issuer's common stock issuable upon settlement of restricted stock units ("RSUs") granted to the Reporting Person. Each RSU represents a contingent right to receive one share of the Issuer's common stock. 25% of the RSUs will vest on May 15, 2027 and the remainder will vest in three approximately equal annual installments thereafter until May 15, 2030, subject to the Reporting Person's continuous service to the Issuer.

The shares underlying this option vest entirely on April 1, 2027.

Represents shares of the Issuer's common stock issuable upon settlement of restricted stock units ("RSUs") granted to the Reporting Person. Each RSU represents a contingent right to receive one share of the Issuer's common stock. 25% of the RSUs will vest on May 15, 2027 and the remainder will vest in three approximately equal annual installments thereafter until May 15, 2030, subject to the Reporting Person's continuous service to the Issuer.

The shares underlying this option vest entirely on April 1, 2027.

44,500 non-qualified stock options ("Stock Options") exercisable solely into common stock ("Common Stock") of Replimune Group, Inc. (the "Issuer") granted by the Issuer to Michael Goller, a full-time employee of Baker Bros. Advisors LP (the "Adviser"), on April 1, 2026, in his capacity as a director of the Issuer, pursuant to the Issuer's 2018 Omnibus Incentive Compensation Plan ("Incentive Plan"). The Stock Options have a strike price of $7.61 per share and vest on April 1, 2027, subject to Michael Goller's continued service on the board of directors of the Issuer (the "Board") through the vesting date or an earlier change in control of the Issuer. The Stock Options expire on April 1, 2036.

Michael Goller serves on the Board as a representative of 667, L.P. ("667") and Baker Brothers Life Sciences, L.P. ("Life Sciences", and together with 667, the "Funds") and their affiliates and control persons.

The Adviser serves as the investment adviser to the Funds. In connection with the services provided by the Adviser, the Adviser receives an asset-based management fee that does not confer any pecuniary interest in the securities held for the benefit of the Funds. Baker Bros. Advisors (GP) LLC (the "Adviser GP") is the Adviser's sole general partner. Julian C. Baker and Felix J. Baker are managing members of the Adviser GP. The Adviser has complete and unlimited discretion and authority with respect to the investment and voting power of the securities held for the benefit of the Funds. The general partners of the Funds relinquished to the Adviser all discretion and authority with respect to the investment and voting power of the securities held for the benefit of the Funds.

Julian C. Baker, Felix J. Baker, the Adviser GP and the Adviser disclaim beneficial ownership of the securities held for the benefit of the Funds except to the extent of their pecuniary interest therein, and this report shall not be deemed an admission that any of Julian C. Baker, Felix J. Baker, the Adviser GP or the Adviser is a beneficial owner of such securities for purposes of Section 16 or any other purpose.

Pursuant to the policies of the Adviser, Michael Goller does not have a right to any of the Issuer's securities issued as compensation for his service on the Board and the Funds are entitled to an indirect proportionate pecuniary interest in such securities. The Funds each own an indirect proportionate pecuniary interest in such securities. Solely as a result of their ownership interest in (i) the general partners of the Funds and (ii) the Funds, Felix J. Baker and Julian C. Baker may be deemed to have an indirect pecuniary interest in the shares of Common Stock, Stock Options and Common Stock issued upon exercise of Stock Options (i.e. no direct pecuniary interest) issued as compensation for such Board service.

Pursuant to the policies of the Adviser, the Adviser has voting and dispositive power over the Stock Options and any Common Stock received as a result of the exercise of Stock Options.

The acquisition of Stock Options reported on this form represents a single grant to Michael Goller of 44,500 Stock Options on Table II. This grant of 44,500 Stock Options for Michael Goller is reported for each of the Funds as each has an indirect pecuniary interest in such securities.

After giving effect to the transaction reported herein and as a result of their ownership interest in (i) Baker Brothers Life Sciences Capital, L.P. and (ii) Life Sciences, Julian C. Baker and Felix J. Baker each may be deemed to have an indirect pecuniary interest in the Stock Options reported in column 9 of Table II held for the benefit of Life Sciences, a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital, L.P., a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital (GP), LLC, due to their interest in Life Sciences and Baker Brothers Life Sciences Capital, L.P.'s right to receive an allocation of a portion of the profits from Life Sciences.

25% of the shares underlying this stock option vest on April 1, 2027, and the remainder of the shares underlying this stock option vest in 36 approximately equal monthly installments thereafter.

The shares underlying this option vest entirely on April 1, 2027.

25% of the shares underlying this stock option vest on April 1, 2027, and the remainder of the shares underlying this stock option vest in 36 approximately equal monthly installments thereafter.

44,500 non-qualified stock options ("Stock Options") exercisable solely into common stock ("Common Stock") of Replimune Group, Inc. (the "Issuer") granted by the Issuer to Michael Goller, a full-time employee of Baker Bros. Advisors LP (the "Adviser"), on April 1, 2026, in his capacity as a director of the Issuer, pursuant to the Issuer's 2018 Omnibus Incentive Compensation Plan ("Incentive Plan"). The Stock Options have a strike price of $7.61 per share and vest on April 1, 2027, subject to Michael Goller's continued service on the board of directors of the Issuer (the "Board") through the vesting date or an earlier change in control of the Issuer. The Stock Options expire on April 1, 2036.

Michael Goller serves on the Board as a representative of 667, L.P. ("667") and Baker Brothers Life Sciences, L.P. ("Life Sciences", and together with 667, the "Funds") and their affiliates and control persons.

The Adviser serves as the investment adviser to the Funds. In connection with the services provided by the Adviser, the Adviser receives an asset-based management fee that does not confer any pecuniary interest in the securities held for the benefit of the Funds. Baker Bros. Advisors (GP) LLC (the "Adviser GP") is the Adviser's sole general partner. Julian C. Baker and Felix J. Baker are managing members of the Adviser GP. The Adviser has complete and unlimited discretion and authority with respect to the investment and voting power of the securities held for the benefit of the Funds. The general partners of the Funds relinquished to the Adviser all discretion and authority with respect to the investment and voting power of the securities held for the benefit of the Funds.

Julian C. Baker, Felix J. Baker, the Adviser GP and the Adviser disclaim beneficial ownership of the securities held for the benefit of the Funds except to the extent of their pecuniary interest therein, and this report shall not be deemed an admission that any of Julian C. Baker, Felix J. Baker, the Adviser GP or the Adviser is a beneficial owner of such securities for purposes of Section 16 or any other purpose.

Pursuant to the policies of the Adviser, Michael Goller does not have a right to any of the Issuer's securities issued as compensation for his service on the Board and the Funds are entitled to an indirect proportionate pecuniary interest in such securities. The Funds each own an indirect proportionate pecuniary interest in such securities. Solely as a result of their ownership interest in (i) the general partners of the Funds and (ii) the Funds, Felix J. Baker and Julian C. Baker may be deemed to have an indirect pecuniary interest in the shares of Common Stock, Stock Options and Common Stock issued upon exercise of Stock Options (i.e. no direct pecuniary interest) issued as compensation for such Board service.

Pursuant to the policies of the Adviser, the Adviser has voting and dispositive power over the Stock Options and any Common Stock received as a result of the exercise of Stock Options.

The acquisition of Stock Options reported on this form represents a single grant to Michael Goller of 44,500 Stock Options on Table II. This grant of 44,500 Stock Options for Michael Goller is reported for each of the Funds as each has an indirect pecuniary interest in such securities.

After giving effect to the transaction reported herein and as a result of their ownership interest in (i) Baker Biotech Capital, L.P. and (ii) 667, Julian C. Baker and Felix J. Baker each may be deemed to have an indirect pecuniary interest in the Stock Options reported in column 9 of Table II held for the benefit of 667, a limited partnership of which the sole general partner is Baker Biotech Capital, L.P., a limited partnership of which the sole general partner is Baker Biotech Capital (GP), LLC, due to their interest in 667 and Baker Biotech Capital, L.P.'s right to receive an allocation of a portion of the profits from 667.

The shares underlying this option vest entirely on April 1, 2027.

25% of the shares underlying this stock option vest on April 1, 2027, and the remainder of the shares underlying this stock option vest in 36 approximately equal monthly installments thereafter.

The shares underlying this option vest entirely on April 1, 2027.

Represents shares of the Issuer's common stock issuable upon settlement of restricted stock units ("RSUs") granted to the Reporting Person. Each RSU represents a contingent right to receive one share of the Issuer's common stock. 25% of the RSUs will vest on May 15, 2027 and the remainder will vest in three approximately equal annual installments thereafter until May 15, 2030, subject to the Reporting Person's continuous service to the Issuer.

Represents shares of the Issuer's common stock issuable upon settlement of restricted stock units ("RSUs") granted to the Reporting Person. Each RSU represents a contingent right to receive one share of the Issuer's common stock. 50% of the RSUs will vest on November 15, 2026 and 50% of the RSUs will vest on November 15, 2027, subject to the Reporting Person's continuous service to the Issuer.

Represents shares of the Issuer's common stock issuable upon settlement of restricted stock units ("RSUs") granted to the Reporting Person. Each RSU represents a contingent right to receive one share of the Issuer's common stock. 50% of the RSUs will vest on November 15, 2026 and 50% of the RSUs will vest on November 15, 2027, subject to the Reporting Person's continuous service to the Issuer.

Represents shares of the Issuer's common stock issuable upon settlement of restricted stock units ("RSUs") granted to the Reporting Person. Each RSU represents a contingent right to receive one share of the Issuer's common stock. 50% of the RSUs will vest on November 15, 2026 and 50% of the RSUs will vest on November 15, 2027, subject to the Reporting Person's continuous service to the Issuer.

Represents shares of the Issuer's common stock issuable upon settlement of restricted stock units ("RSUs") granted to the Reporting Person. Each RSU represents a contingent right to receive one share of the Issuer's common stock. 50% of the RSUs will vest on November 15, 2026 and 50% of the RSUs will vest on November 15, 2027, subject to the Reporting Person's continuous service to the Issuer.

Represents shares of the Issuer's common stock issuable upon settlement of restricted stock units ("RSUs") granted to the Reporting Person. Each RSU represents a contingent right to receive one share of the Issuer's common stock. 50% of the RSUs will vest on November 15, 2026 and 50% of the RSUs will vest on November 15, 2027, subject to the Reporting Person's continuous service to the Issuer.

The reporting person exercised the option due to the upcoming expiration date of the option.

All of the shares underlying this stock option vested on January 21, 2016.

The sales reported on this Form 4 were made by the reporting person pursuant to a trading plan adopted on June 2, 2025, that is intended to comply with Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended.

The price reported reflects a weighted average price. These shares were sold in multiple transactions at prices ranging from $11.00 to $11.26. The reporting person will provide to the Issuer, any security holder of the Issuer or the SEC staff, upon request, information regarding the number of shares sold at each price within the range.

Following the sales reported on this Form 4, the reporting person continues to beneficially own 333,576 shares of the Issuer's common stock, including restricted stock units. The reporting person also holds options to acquire an aggregate of 753,750 shares of the Issuer's common stock, 331,353 of which are exercisable as of the date hereof.

Represents shares of the Issuer's common stock (the "Shares") sold to cover tax withholding obligations in connection with the partial vesting of the Reporting Person's Restricted Stock Units ("RSU"). The transaction reported herein was made in accordance with the irrevocable "sell to cover" provision set forth in the award agreements under which the RSUs were granted and does not represent a discretionary sale by the Reporting Person.

The price reported reflects a weighted average price of the Shares calculated by the broker executing the sell-to-cover transactions. The Shares were sold as part of a block trade in multiple transactions at prices ranging from $8.88 to $9.26 per Share. The Reporting Person will provide to the Issuer, any security holder of the Issuer or the Securities Exchange Commission staff, upon request, information regarding the number of Shares sold at each price within the range.

Represents shares of the Issuer's common stock (the "Shares") sold to cover tax withholding obligations in connection with the partial vesting of the Reporting Person's Restricted Stock Units ("RSU"). The transaction reported herein was made in accordance with the irrevocable "sell to cover" provision set forth in the award agreements under which the RSUs were granted and does not represent a discretionary sale by the Reporting Person.

The price reported reflects a weighted average price of the Shares calculated by the broker executing the sell-to-cover transactions. The Shares were sold as part of a block trade in multiple transactions at prices ranging from $8.88 to $9.26 per Share. The Reporting Person will provide to the Issuer, any security holder of the Issuer or the Securities Exchange Commission staff, upon request, information regarding the number of Shares sold at each price within the range.

Represents shares of the Issuer's common stock (the "Shares") sold to cover tax withholding obligations in connection with the partial vesting of the Reporting Person's Restricted Stock Units ("RSU"). The transaction reported herein was made in accordance with the irrevocable "sell to cover" provision set forth in the award agreements under which the RSUs were granted and does not represent a discretionary sale by the Reporting Person.

Represents shares of the Issuer's common stock (the "Shares") sold to cover tax withholding obligations in connection with the partial vesting of the Reporting Person's Restricted Stock Units ("RSU"). The transaction reported herein was made in accordance with the irrevocable "sell to cover" provision set forth in the award agreements under which the RSUs were granted and does not represent a discretionary sale by the Reporting Person.

The price reported reflects a weighted average price of the Shares. The Shares were sold in multiple transactions at prices ranging from $8.05 to $8.80 per Share. The Reporting Person will provide to the Issuer, any security holder of the Issuer or the Securities Exchange Commission staff, upon request, information regarding the number of Shares sold at each price within the range.

Represents shares of the Issuer's common stock (the "Shares") sold to cover tax withholding obligations in connection with the partial vesting of the Reporting Person's Restricted Stock Units ("RSU"). The transaction reported herein was made in accordance with the irrevocable "sell to cover" provision set forth in the award agreements under which the RSUs were granted and does not represent a discretionary sale by the Reporting Person.

The price reported reflects a weighted average price of the Shares. The Shares were sold in multiple transactions at prices ranging from $8.05 to $8.80 per Share. The Reporting Person will provide to the Issuer, any security holder of the Issuer or the Securities Exchange Commission staff, upon request, information regarding the number of Shares sold at each price within the range.

Represents shares of the Issuer's common stock (the "Shares") sold to cover tax withholding obligations in connection with the partial vesting of the Reporting Person's Restricted Stock Units ("RSU"). The transaction reported herein was made in accordance with the irrevocable "sell to cover" provision set forth in the award agreements under which the RSUs were granted and does not represent a discretionary sale by the Reporting Person.

The price reported reflects a weighted average price of the Shares. The Shares were sold in multiple transactions at prices ranging from $8.05 to $8.80 per Share. The Reporting Person will provide to the Issuer, any security holder of the Issuer or the Securities Exchange Commission staff, upon request, information regarding the number of Shares sold at each price within the range.

Represents shares of the Issuer's common stock (the "Shares") sold to cover tax withholding obligations in connection with the partial vesting of the Reporting Person's Restricted Stock Units ("RSU"). The transaction reported herein was made in accordance with the irrevocable "sell to cover" provision set forth in the award agreements under which the RSUs were granted and does not represent a discretionary sale by the Reporting Person.

The price reported reflects a weighted average price of the Shares. The Shares were sold in multiple transactions at prices ranging from $8.05 to $8.80 per Share. The Reporting Person will provide to the Issuer, any security holder of the Issuer or the Securities Exchange Commission staff, upon request, information regarding the number of Shares sold at each price within the range.

Represents shares of the Issuer's common stock (the "Shares") sold to cover tax withholding obligations in connection with the partial vesting of the Reporting Person's Restricted Stock Units ("RSU"). The transaction reported herein was made in accordance with the irrevocable "sell to cover" provision set forth in the award agreements under which the RSUs were granted and does not represent a discretionary sale by the Reporting Person.

The price reported reflects a weighted average price of the Shares. The Shares were sold in multiple transactions at prices ranging from $8.05 to $8.79 per Share. The Reporting Person will provide to the Issuer, any security holder of the Issuer or the Securities Exchange Commission staff, upon request, information regarding the number of Shares sold at each price within the range.

Represents shares of the Issuer's common stock (the "Shares") sold to cover tax withholding obligations in connection with the partial vesting of the Reporting Person's Restricted Stock Units ("RSU"). The transaction reported herein was made in accordance with the irrevocable "sell to cover" provision set forth in the award agreements under which the RSUs were granted and does not represent a discretionary sale by the Reporting Person.

The price reported reflects a weighted average price of the Shares. The Shares were sold in multiple transactions at prices ranging from $8.05 to $8.80 per Share. The Reporting Person will provide to the Issuer, any security holder of the Issuer or the Securities Exchange Commission staff, upon request, information regarding the number of Shares sold at each price within the range.

The shares underlying this option vest entirely on April 1, 2026.

The shares underlying this option vest entirely on April 1, 2026.