Company: SION
Filing Date: 2025-04-29
Form Type: DEF 14A
Source: 0001193125-25-101830
Chunk: 54

Company: Sionna Therapeutics, Inc.
Filing Date: 2025-04-29
Form: DEF 14A
Chunk 54
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. Entities affiliated with RA Capital beneficially own more than 5% of our outstanding capital stock. Joshua Resnick, M.D., M.B.A., a member of our board of directors, is a senior managing director at RA Capital. |

| (5) | Sionna Aggregator, LP beneficially owns more than 5% of our outstanding capital stock. Sionna Aggregator, LP is an affiliate of Enavate Sciences. H. Edward Fleming, Jr., M.D., a member of our board of directors, is an executive vice president of commercialization at Enavate Sciences. |

| (6) | Consists of 1,765,541 shares of Series C preferred stock held by The Rise Fund Sling II, L.P. Entities affiliated with TPG Growth beneficially owns more than 5% of our outstanding capital stock. Lucian Iancovici, M.D., a member of our board of directors, is a managing director at TPG Growth. |

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| (7) | Consists of (i) 1,715,837 shares of Series C preferred stock held by Viking Global Opportunities Illiquid Investments Sub-Master LP and (ii) 845,113 shares of Series C preferred stock held by Viking Global Opportunities Drawdown (Aggregator) LP. Entities affiliated with Viking Global Opportunities beneficially own more than 5% of our outstanding capital stock. |

Participation in our Initial Public Offering Our existing stockholders, including certain affiliates of our directors, purchased an aggregate of 3,410,000 shares of our common stock in our initial public offering in February 2025, at the initial public offering price. The following table sets forth the number of shares of our common stock purchased by directors, executive officers and five percent stockholders and their affiliates and the aggregate purchase price paid for such shares.

| Stockholder                               |     | Shares of 
 Common    
 Stock     |           |     | Total    
 Purchase 
 Price    |            |
|:------------------------------------------|:----|:----------|----------:|:----|:---------|-----------:|
| Entities affiliated with TPG Growth(1)    |     |           | 1,125,000 |     | $        | 20,250,000 |
| Entities affiliated with RA Capital(2)    |     |           | 1,125,000 |     | $        | 20,250,000 |
| Entities affiliated with Atlas Venture(3) |     |           |