| Name | Relationship | Address | Signature | Signature date | CIK |
|---|---|---|---|---|---|
| EVNIN LUKE | Director | C/O MPM BIOIMPACT LLC, 399 BOYLSTON STREET, SUITE 1100, BOSTON | /s/ Luke Evnin | 04 Dec 2025 | 0001134657 |
| Type | Sym | Class | Transaction | Value $ | Shares | Change % | * Price $ | Shares After | Date | Ownership | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|
| transaction | HOWL | Common Stock | Sale | -$33.9K | -38K | -1.19% | $0.89 | 3.16M | 02 Dec 2025 | See Footnotes | F1, F2, F3, F4, F5 |
| transaction | HOWL | Common Stock | Sale | -$32K | -36.7K | -1.16% | $0.87 | 3.12M | 03 Dec 2025 | See Footnotes | F1, F4, F6, F7, F8 |
| transaction | HOWL | Common Stock | Sale | -$51.8K | -53.4K | -1.71% | $0.97 | 3.07M | 04 Dec 2025 | 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: 4,070 by MPM Asset Management LLC ("AM LLC"), 25,712 by MPM BioVentures 2014, L.P. ("BV 2014"), 1,715 by MPM BioVentures 2014(B), L.P. ("BV 2014(B)"), 884 by MPM Asset Management Investors BV2014 LLC ("AM BV2014") and 5,662 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 $0.852 to $0.9246 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: 338,231 by AM LLC, 2,135,926 by BV 2014, 142,463 by BV 2014(B), 73,518 by AM BV2014 and 468,282 by MPM OIF. |
| F6 | The shares were sold as follows: 3,929 by AM LLC, 24,821 by BV 2014, 1,656 by BV 2014(B), 854 by AM BV2014 and 5,466 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 $0.82 to $0.9256 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: 334,302 by AM LLC, 2,111,105 by BV 2014, 140,807 by BV 2014(B), 72,664 by AM BV2014 and 462,816 by MPM OIF. |
| F9 | The shares were sold as follows: 5,714 by AM LLC, 36,101 by BV 2014, 2,408 by BV 2014(B), 1,243 by AM BV2014 and 7,950 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 $0.92 to $1.0208 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: 328,588 by AM LLC, 2,075,004 by BV 2014, 138,399 by BV 2014(B), 71,421 by AM BV2014 and 454,866 by MPM OIF. |