| Name | Relationship | Address | Signature | Signature date | CIK |
|---|---|---|---|---|---|
| EVNIN LUKE | Director | C/O MPM BIOIMPACT LLC, 399 BOYLSTON STREET, SUITE 1100, BOSTON | /s/ Luke Evnin | 2025-11-25 | 0001134657 |
| Type | Sym | Class | Transaction | Value $ | Shares | Change % | * Price $ | Shares After | Date | Ownership | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|
| transaction | HOWL | Common Stock | Sale | -$34.3K | -41.3K | -1.21% | $0.83 | 3.37M | Nov 21, 2025 | See Footnotes | F1, F2, F3, F4, F5 |
| transaction | HOWL | Common Stock | Sale | -$55.9K | -57K | -1.69% | $0.98 | 3.31M | Nov 24, 2025 | See Footnotes | F1, F4, F6, F7, F8 |
| transaction | HOWL | Common Stock | Sale | -$25.1K | -27.3K | -0.82% | $0.92 | 3.29M | Nov 25, 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: 4,417 by MPM Asset Management LLC ("AM LLC"), 27,904 by MPM BioVentures 2014, L.P. ("BV 2014"), 1,861 by MPM BioVentures 2014(B), L.P. ("BV 2014(B)"), 960 by MPM Asset Management Investors BV2014 LLC ("AM BV2014") and 6,145 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 $0.80 to $0.8861 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: 361,062 by AM LLC, 2,280,166 by BV 2014, 152,083 by BV 2014(B), 78,482 by AM BV2014 and 500,047 by MPM OIF. |
| F6 | The shares were sold as follows: 6,097 by AM LLC, 38,518 by BV 2014, 2,569 by BV 2014(B), 1,325 by AM BV2014 and 8,483 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 $0.8733 to $1.03 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: 354,965 by AM LLC, 2,241,648 by BV 2014, 149,514 by BV 2014(B), 77,157 by AM BV2014 and 491,564 by MPM OIF. |
| F9 | The shares were sold as follows: 2,920 by AM LLC, 18,449 by BV 2014, 1,230 by BV 2014(B), 635 by AM BV2014 and 4,063 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 $0.90 to $0.99 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: 352,045 by AM LLC, 2,223,199 by BV 2014, 148,284 by BV 2014(B), 76,522 by AM BV2014 and 487,501 by MPM OIF. |