| Name | Relationship | Address | Signature | Signature date | CIK |
|---|---|---|---|---|---|
| EVNIN LUKE | Director | C/O MPM BIOIMPACT LLC, 399 BOYLSTON STREET, SUITE 1100, BOSTON | /s/ Luke Evnin | 15 Jan 2026 | 0001134657 |
| Type | Sym | Class | Transaction | Value $ | Shares | Change % | * Price $ | Shares After | Date | Ownership | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|
| transaction | HOWL | Common Stock | Sale | $23,759 | -43,198 | -1.9% | $0.5500 | 2,266,671 | 13 Jan 2026 | See Footnotes | F1, F2, F3, F4, F5 |
| transaction | HOWL | Common Stock | Sale | $17,451 | -30,616 | -1.4% | $0.5700 | 2,236,055 | 14 Jan 2026 | See Footnotes | F1, F4, F6, F7, F8 |
| transaction | HOWL | Common Stock | Sale | $20,577 | -37,413 | -1.7% | $0.5500 | 2,198,642 | 15 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: 4,621 by MPM Asset Management LLC ("AM LLC"), 29,195 by MPM BioVentures 2014, L.P. ("BV 2014"), 1,947 by MPM BioVentures 2014(B), L.P. ("BV 2014(B)"), 1,006 by MPM Asset Management Investors BV2014 LLC ("AM BV2014") and 6,429 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 $0.53675 to $0.5697 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: 242,837 by AM LLC, 1,533,244 by BV 2014, 102,265 by BV 2014(B), 52,766 by AM BV2014 and 335,559 by MPM OIF. |
| F6 | The shares were sold as follows: 3,275 by AM LLC, 20,692 by BV 2014, 1,380 by BV 2014(B), 712 by AM BV2014 and 4,557 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 $0.5524 to $0.5857 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: 239,562 by AM LLC, 1,512,552 by BV 2014, 100,885 by BV 2014(B), 52,054 by AM BV2014 and 331,002 by MPM OIF. |
| F9 | The shares were sold as follows: 4,002 by AM LLC, 25,285 by BV 2014, 1,686 by BV 2014(B), 872 by AM BV2014 and 5,568 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 $0.5305 to $0.59 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: 235,560 by AM LLC, 1,487,267 by BV 2014, 99,199 by BV 2014(B), 51,182 by AM BV2014 and 325,434 by MPM OIF. |