| Name | Relationship | Address | Signature | Signature date | CIK |
|---|---|---|---|---|---|
| EVNIN LUKE | Director | C/O MPM BIOIMPACT LLC, 399 BOYLSTON STREET, SUITE 1100, BOSTON | /s/ Luke Evnin | 07 Jan 2026 | 0001134657 |
| Type | Sym | Class | Transaction | Value $ | Shares | Change % | * Price $ | Shares After | Date | Ownership | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|
| transaction | HOWL | Common Stock | Sale | $11,762 | -18,378 | -0.74% | $0.6400 | 2,453,919 | 05 Jan 2026 | See Footnotes | F1, F2, F3, F4, F5 |
| transaction | HOWL | Common Stock | Sale | $26,495 | -40,761 | -1.7% | $0.6500 | 2,413,158 | 06 Jan 2026 | See Footnotes | F1, F4, F6, F7, F8 |
| transaction | HOWL | Common Stock | Sale | $7,626 | -11,915 | -0.49% | $0.6400 | 2,401,243 | 07 Jan 2026 | See Footnotes | F1, F4, F9, F10, F11 |
Buy Plan / Sale Plan: These are also open market purchases/sales of shares, but in this case the transaction is part of a trading plan. Rule 10b5-1 allows insiders to setup a trading plan to buy/sell stocks over a certain period of time. Since the purchases/sales are predetermined, this protects the insiders from violating insider trading law.
Transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c).
| Id | Content |
|---|---|
| F1 | Transaction effected pursuant to a plan established pursuant to Rule 10b5-1 dated September 24, 2025. |
| F2 | The shares were sold as follows: 1,966 by MPM Asset Management LLC ("AM LLC"), 12,420 by MPM BioVentures 2014, L.P. ("BV 2014"), 828 by MPM BioVentures 2014(B), L.P. ("BV 2014(B)"), 429 by MPM Asset Management Investors BV2014 LLC ("AM BV2014") and 2,735 by MPM Oncology Innovations Fund, L.P. ("MPM OIF"). |
| F3 | The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $0.63435 to $0.6549 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 sold at each separate price within the range set forth in this footnote. |
| F4 | MPM BioVentures 2014 GP LLC and MPM BioVentures 2014 LLC ("BV LLC") are the direct and indirect general partners of BV 2014 and BV 2014(B). BV LLC is the manager of AM BV2014. MPM Oncology Innovations Fund GP LLC ("MPM OIF GP") is the general partner of MPM OIF. Luke Evnin is a member of AM LLC, a Managing Director of BV LLC and a manager of MPM OIF GP. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein. |
| F5 | The shares are held as follows: 262,868 by AM LLC, 1,659,794 by BV 2014, 110,705 by BV 2014(B), 57,125 by AM BV2014 and 363,427 by MPM OIF. |
| F6 | The shares were sold as follows: 4,361 by AM LLC, 27,548 by BV 2014, 1,837 by BV 2014(B), 948 by AM BV2014 and 6,067 by MPM OIF. |
| F7 | The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $0.64 to $0.6599 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 sold at each separate price within the range set forth in this footnote. |
| F8 | The shares are held as follows: 258,507 by AM LLC, 1,632,246 by BV 2014, 108,868 by BV 2014(B), 56,177 by AM BV2014 and 357,360 by MPM OIF. |
| F9 | The shares were sold as follows: 1,275 by AM LLC, 8,053 by BV 2014, 537 by BV 2014(B), 277 by AM BV2014 and 1,773 by MPM OIF. |
| F10 | The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $0.6276 to $0.6598 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 sold at each separate price within the range set forth in this footnote. |
| F11 | The shares are held as follows: 257,232 by AM LLC, 1,624,193 by BV 2014, 108,331 by BV 2014(B), 55,900 by AM BV2014 and 355,587 by MPM OIF. |