| Name | Relationship | Address | Signature | Signature date | CIK |
|---|---|---|---|---|---|
| EVNIN LUKE | Director | C/O MPM BIOIMPACT LLC, 399 BOYLSTON STREET, SUITE 1100, BOSTON | /s/ Luke Evnin | 29 Oct 2025 | 0001134657 |
| Type | Sym | Class | Transaction | Value $ | Shares | Change % | * Price $ | Shares After | Date | Ownership | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|
| transaction | HOWL | Common Stock | Sale | -$80.3K | -46.7K | -1.08% | $1.72 | 4.26M | 27 Oct 2025 | See Footnote | F1, F2, F3, F4 |
| transaction | HOWL | Common Stock | Sale | -$72.7K | -44.3K | -1.04% | $1.64 | 4.22M | 28 Oct 2025 | See Footnote | F1, F5, F6, F7 |
| transaction | HOWL | Common Stock | Sale | -$134K | -86.2K | -2.04% | $1.55 | 4.13M | 29 Oct 2025 | See Footnote | F1, F8, F9, F10 |
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: 4,992 by MPM Asset Management LLC ("AM LLC"), 31,538 by MPM BioVentures 2014, L.P. ("BV 2014"), 2,104 by MPM BioVentures 2014(B), L.P. ("BV 2014(B)"), 1,085 by MPM Asset Management Investors BV2014 LLC ("AM BV2014") and 6,945 by MPM Oncology Innovations Fund, L.P. ("MPM OIF"). 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. |
| F3 | The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $1.675 to $1.82 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 | The shares are held as follows: 456,416 by AM LLC, 2,882,585 by BV 2014, 192,263 by BV 2014(B), 99,218 by AM BV2014 and 632,714 by MPM OIF. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein. |
| F5 | The were sold as follows: 4,742 by AM LLC, 29,958 by BV 2014, 1,998 by BV 2014(B), 1,031 by AM BV2014 and 6,598 by MPM OIF. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein. |
| F6 | The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $1.605 to $1.70 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. |
| F7 | The shares are held as follows: 451,674 by AM LLC, 2,852,627 by BV 2014, 190,265 by BV 2014(B), 98,187 by AM BV2014 and 626,116 by MPM OIF. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein. |
| F8 | The were sold as follows: 9,216 by AM LLC, 58,227 by BV 2014, 3,884 by BV 2014(B), 2,004 by AM BV2014 and 12,823 by MPM OIF. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein. |
| F9 | The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $1.51 to $1.62 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. |
| F10 | The shares are held as follows: 442,458 by AM LLC, 2,794,400 by BV 2014, 186,381 by BV 2014(B), 96,183 by AM BV2014 and 613,293 by MPM OIF. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein. |