| Name | Relationship | Address | Signature | Signature date | CIK |
|---|---|---|---|---|---|
| RA CAPITAL MANAGEMENT, L.P. | Director, 10%+ Owner | 200 BERKELEY STREET, 18TH FLOOR, BOSTON | /s/ Peter Kolchinsky, Manager of RA Capital Management, L.P. | 2025-11-24 | 0001346824 |
| RA Capital Healthcare Fund LP | Director, 10%+ Owner | C/O RA CAPITAL MANAGEMENT, L.P., 200 BERKELEY STREET, 18TH FLOOR, BOSTON | /s/ Peter Kolchinsky, Manager of RA Capital Healthcare Fund GP, LLC, the General Partner of RA Capital Healthcare Fund, L.P. | 2025-11-24 | 0001315082 |
| RA Capital Nexus Fund, L.P. | Director | C/O RA CAPITAL MANAGEMENT, L.P., 200 BERKELEY STREET, 18TH FLOOR, BOSTON | /s/ Peter Kolchinsky, Manager of RA Capital Nexus Fund GP, LLC, the General Partner of RA Capital Nexus Fund, L.P. | 2025-11-24 | 0001780117 |
| RA Capital Nexus Fund III, L.P. | Director | C/O RA CAPITAL MANAGEMENT, L.P., 200 BERKELEY STREET, 18TH FLOOR, BOSTON | /s/ Peter Kolchinsky, Manager of RA Capital Nexus Fund III GP, LLC, the General Partner of RA Capital Nexus Fund III, L.P. | 2025-11-24 | 0001883840 |
| Kolchinsky Peter | Director, 10%+ Owner | C/O RA CAPITAL MANAGEMENT, L.P., 200 BERKELEY STREET, 18TH FLOOR, BOSTON | /s/ Peter Kolchinsky, individually | 2025-11-24 | 0001384859 |
| Shah Rajeev M. | Director, 10%+ Owner | C/O RA CAPITAL MANAGEMENT, L.P., 200 BERKELEY STREET, 18TH FLOOR, BOSTON | /s/ Rajeev Shah, individually | 2025-11-24 | 0001619841 |
| Type | Sym | Class | Transaction | Value $ | Shares | Change % | * Price $ | Shares After | Date | Ownership | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|
| transaction | SION | Common Stock | Sale | -$5.98K | -150 | 0% | $39.89 | 6.9M | Nov 20, 2025 | See footnotes | F1, F2, F3 |
| transaction | SION | Common Stock | Sale | -$49.3K | -1.24K | -0.19% | $39.89 | 661K | Nov 20, 2025 | See footnotes | F1, F3, F4 |
| transaction | SION | Common Stock | Sale | -$32K | -801 | -0.04% | $39.89 | 2.21M | Nov 20, 2025 | See footnotes | F1, F3, F5 |
| transaction | SION | Common Stock | Sale | -$37.8K | -947 | -0.56% | $39.89 | 167K | Nov 20, 2025 | See footnotes | F1, F3, F6 |
| transaction | SION | Common Stock | Sale | -$3.89K | -96 | 0% | $40.50 | 6.9M | Nov 20, 2025 | See footnotes | F2, F3, F7 |
| transaction | SION | Common Stock | Sale | -$31.9K | -788 | -0.12% | $40.50 | 660K | Nov 20, 2025 | See footnotes | F3, F4, F7 |
| transaction | SION | Common Stock | Sale | -$20.7K | -512 | -0.02% | $40.50 | 2.2M | Nov 20, 2025 | See footnotes | F3, F5, F7 |
| transaction | SION | Common Stock | Sale | -$24.5K | -604 | -0.36% | $40.50 | 167K | Nov 20, 2025 | See footnotes | F3, F6, F7 |
| transaction | SION | Common Stock | Sale | -$47.8K | -1.21K | -0.02% | $39.50 | 6.9M | Nov 21, 2025 | See footnotes | F2, F3, F8 |
| transaction | SION | Common Stock | Sale | -$392K | -9.92K | -1.5% | $39.50 | 650K | Nov 21, 2025 | See footnotes | F3, F4, F8 |
| transaction | SION | Common Stock | Sale | -$254K | -6.44K | -0.29% | $39.50 | 2.2M | Nov 21, 2025 | See footnotes | F3, F5, F8 |
| transaction | SION | Common Stock | Sale | -$301K | -7.61K | -4.57% | $39.50 | 159K | Nov 21, 2025 | See footnotes | F3, F6, F8 |
| Id | Content |
|---|---|
| F1 | The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $39.40 to $40.00 inclusive. The Reporting Persons undertake 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. |
| F2 | Held directly by RA Capital Healthcare Fund, L.P. (the "Fund"). |
| F3 | RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund, RA Capital Nexus Fund, L.P. (the "Nexus Fund"), RA Capital Nexus III Fund, L.P. (the "Nexus Fund III"), and a separately managed account (the "Account"). The general partner of the Adviser is RA Capital Management GP, LLC (the "Adviser GP"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, the Fund, the Nexus Fund, the Nexus Fund III, Dr. Kolchinsky and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein. |
| F4 | Held directly by the Nexus Fund. |
| F5 | Held directly by the Nexus Fund III. |
| F6 | Held directly by the Account. |
| F7 | The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $40.50 to $40.51 inclusive. The Reporting Persons undertake 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 price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $39.50 to $40.00 inclusive. The Reporting Persons undertake 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. |
Joshua Resnick, a Partner of the Adviser, serves on the Issuer's board of directors.