Every Form 4 that Sionna Therapeutics, Inc. (SION) has filed with the SEC in the last 12 months is listed below, newest first, and each one links through to the document itself with the summary and the scores our analysis gives it.
A Form 4 covers the transactions officers, directors and large holders report, so if you follow SION and want that one kind of document rather than the whole filing history, this is the page to keep. The company's other filings, of every form, are on the full SION filings page.
Sionna Therapeutics, Inc. (SION) had large shareholder entities affiliated with RA Capital report open-market sales of its common stock on September 17, 2026. RA Capital Healthcare Fund LP sold 3,415,011 shares at $6.32 per share and a further 33,800 shares at a weighted average price of $7.46 per share, in multiple trades between $7.30 and $7.68. The transactions were reported as indirectly held and the RA Capital adviser, its general partner and principals Peter Kolchinsky and Rajeev Shah disclaim beneficial ownership except to the extent of their pecuniary interest. No Rule 10b5-1 trading plan is reported.
Sionna Therapeutics, Inc. reported equity compensation changes for its CFO and CBO, Elena Ridloff. On September 17, 2026, she received a non-qualified stock option for 165,440 shares of common stock at an exercise price of $7.18 per share, reflecting an option repricing that replaced a prior option over the same number of shares with a $39.21 exercise price. She was also granted 47,269 time-based RSUs vesting on June 17, 2027 and 47,268 performance-based RSUs that vest upon achievement of a designated performance milestone, in each case subject to continued service.
Sionna Therapeutics, Inc. (SION) reported that its CMO and Head of R&D, Charlotte McKee, received equity awards and an option repricing on September 17, 2026. She was granted 100,000 RSUs, split between time-based and performance-based vesting, and an existing stock option for 155,700 shares was repriced to an exercise price of $7.18 per share, replacing an option with an exercise price of $39.21 per share. The repriced option and RSUs are issued under the company’s 2025 Stock Option and Incentive Plan and remain subject to service-based vesting and, for part of the RSUs, achievement of a performance milestone. No Rule 10b5-1 trading plan is reported.
Sionna Therapeutics, Inc. (SION) reported equity compensation changes for its CLO and Head of Program Mgmt., Jennifer Fitzpatrick, on September 17, 2026. A stock option for 103,140 shares with a prior exercise price of $39.21 was repriced to $7.18, with all other terms unchanged. Fitzpatrick also received two grants of restricted stock units totaling 56,265 RSUs, half time-based vesting on June 17, 2027 and half vesting upon achievement of a performance milestone, all subject to continued service.
Sionna Therapeutics, Inc. (SION) reported that President & CEO Michael Cloonan received equity awards and an option repricing on September 17, 2026. He was granted 218,050 shares of Common Stock in the form of restricted stock units, split evenly between time-based vesting on June 17, 2027 and performance-based vesting upon a designated milestone. On the same date, a non-qualified stock option for 436,100 shares was repriced to have an exercise price of $7.18 per share, replacing an option with a $39.21 exercise price, with all other terms unchanged and subject to a retention period and prior vesting conditions.
Sionna Therapeutics director-affiliated fund reports share sale. An entity associated with director Peter A. Thompson, OrbiMed Private Investments VIII, LP, sold 85,918 shares of Sionna Therapeutics common stock in an open-market transaction at $44.86 per share pursuant to a Rule 10b5-1 plan. Following the sale, the entity continues to hold 2,469,959 shares indirectly. OrbiMed-related entities and the reporting person may be deemed to have beneficial ownership through control relationships but each disclaims beneficial ownership beyond any pecuniary interest.
ORBIMED ADVISORS LLC and OrbiMed Capital GP VIII LLC, reporting as directors of Sionna Therapeutics, Inc., reported an indirect open‑market sale of common stock. On July 7, 2026, an affiliated investment fund sold 85,918 shares of Sionna common stock at $44.86 per share.
The sold shares are held of record by OrbiMed Private Investments VIII, LP, for which OrbiMed Capital GP VIII LLC is the general partner and OrbiMed Advisors LLC is the managing member. Following this sale, indirect holdings reported for the OrbiMed entities totaled 2,469,959 shares of Sionna common stock. The sale was executed under a Rule 10b5-1 trading plan, and the reporting persons disclaim beneficial ownership of the securities except to the extent of any pecuniary interest.
Sionna Therapeutics, Inc. Chief Legal Officer Jennifer Fitzpatrick reported an exercise-and-sell transaction involving company common stock. She exercised options to acquire 10,250 shares of common stock at an exercise price of $6.11 per share and sold the same 10,250 shares in an open-market transaction at a weighted-average price of $43.5963 per share. The filing states that this sale was automatically executed under a Rule 10b5-1 trading plan adopted on June 5, 2025. Following these transactions, the report shows she holds no shares of common stock directly. The underlying option grant vested 25% on June 3, 2025, with the remainder vesting in thirty-six equal monthly installments, subject to continued service.
Sionna Therapeutics director-affiliated fund reports planned share sale. OrbiMed Private Investments VIII LP, an entity associated with director Peter A. Thompson, sold 115,844 shares of Sionna Therapeutics common stock in an open-market transaction at $45.50 per share under a Rule 10b5-1 trading plan. Following this sale, 2,555,877 shares of Sionna common stock are reported as indirectly held, with OrbiMed-related entities and the reporting person disclaiming beneficial ownership beyond any pecuniary interest.
OrbiMed-affiliated entities reported an open-market sale of Sionna Therapeutics stock under a pre-arranged trading plan. An entity associated with OrbiMed sold 115,844 shares of Sionna Therapeutics, Inc. common stock at a price of $45.50 per share pursuant to a Rule 10b5-1 plan. After this transaction, the OrbiMed-related holder continues to own 2,555,877 shares indirectly through OrbiMed Private Investments VIII, LP, reflecting a large remaining position. OrbiMed Capital GP VIII LLC and OrbiMed Advisors LLC may be deemed to share voting and investment power over these shares, but they each disclaim beneficial ownership beyond any pecuniary interest.
Sionna Therapeutics director Laurie Stelzer received a grant of non-qualified stock options covering 17,340 shares of common stock. The options have an exercise price of $36.73 per share and expire on June 16, 2036.
The option vests in full on the earlier of June 17, 2027 or the date of Sionna Therapeutics’ next annual meeting, subject to her continued service. Following this grant, Stelzer holds options for 17,340 underlying shares directly, reflecting a routine equity-based compensation award rather than an open-market share purchase or sale.
Sionna Therapeutics director Joanne L. Viney received a grant of a non-qualified stock option covering 17,340 shares of common stock. The option has an exercise price of $36.73 per share and expires on June 16, 2036.
The option vests in full on the earlier of June 17, 2027 or the date of Sionna’s next annual meeting, subject to her continued service as a director. Following this award, she holds options representing the right to acquire 17,340 shares directly. This is a compensation-related award, not an open-market purchase or sale.
Sionna Therapeutics director Peter A. Thompson reported a grant of 17,340 non-qualified stock options linked to Sionna Therapeutics, Inc. common stock. The options have an exercise price of $36.73 per share and expire on June 16, 2036. They vest in full on the earlier of June 17, 2027 or the date of the next annual meeting of Sionna Therapeutics, Inc., contingent on his continued service. Under an agreement with OrbiMed Advisors LLC and OrbiMed Capital GP VIII LLC, any securities or economic benefits from these options are to be transferred so that the economic benefit is provided to OrbiMed Private Investments VIII, LP.
Sionna Therapeutics, Inc. reported a Form 4 showing a grant of a non-qualified stock option covering 17,340 shares of common stock. The option has an exercise price of $36.73 per share and expires on June 16, 2036.
According to the footnotes, Dr. Resnick holds this option for the benefit of RA Capital-managed vehicles, and any net cash or stock from exercise will offset advisory fees owed to those funds. RA Capital Management, affiliated funds, and their principals disclaim beneficial ownership of the option and underlying shares except for any pecuniary interest.
Sionna Therapeutics director Marcella K. Ruddy received a new equity award. She was granted a non-qualified stock option covering 17,340 shares of Common Stock at an exercise price of $36.73 per share, expiring on June 16, 2036.
The option vests in full on the earlier of June 17, 2027 or the date of Sionna Therapeutics, Inc.’s next annual meeting, subject to her continued service through the vesting date. Following this grant, she holds 17,340 option shares directly.
Sionna Therapeutics director Joshua Resnick reported a grant of non-qualified stock options linked to 17,340 shares of Common Stock. The options have an exercise price of $36.73 per share and expire on June 16, 2036. They vest in full on the earlier of June 17, 2027 or the date of the next annual meeting, contingent on his continued board service. Under an arrangement with RA Capital Management, L.P., any net cash or stock from exercising these options is turned over for the benefit of RA Capital’s funds and a managed account, and Resnick disclaims beneficial ownership of the options and underlying shares.
Sionna Therapeutics reported a new stock option grant connected to director Harold Edward Fleming’s board service. The award covers 17,340 Non-Qualified Stock Options with an exercise price of $36.73 per share, expiring on June 16, 2036. According to the disclosure, Fleming has agreed to receive and hold these securities for the benefit of Enavate Sciences, LP and disclaims beneficial ownership and all rights in the option and the underlying shares. The option vests in full on the earlier of June 17, 2027 or the date of the next annual meeting of Sionna Therapeutics, Inc., subject to continued board service.
Sionna Therapeutics director Paul J. Clancy received a new stock option award. He was granted a non-qualified option for 17,340 shares of common stock at an exercise price of $36.73 per share, expiring on June 16, 2036.
The option vests in full on the earlier of June 17, 2027 or the date of Sionna Therapeutics' next annual meeting, as long as he continues to serve through that vesting date. Following this grant, the filing shows Clancy holding 17,340 option shares directly.
Sionna Therapeutics director Bruce Booth received a grant of 17,340 non-qualified stock options to buy common stock at $36.73 per share. The options expire on June 16, 2036 and vest in full on the earlier of June 17, 2027 or the next annual meeting, subject to his continued service. Any proceeds from future sales of shares issued upon exercise will be transferred to Atlas Venture Life Science Advisors, LLC, and Booth disclaims ownership except for any pecuniary interest.
OrbiMed Private Investments VIII, LP, an entity associated with Sionna Therapeutics director Peter A. Thompson, sold 101 shares of Sionna Therapeutics common stock at $44.49 per share in an open-market transaction on May 27, 2026.
The sale was executed pursuant to a Rule 10b5-1 trading plan. After this transaction, entities associated with OrbiMed continued to hold 2,671,721 shares indirectly, indicating that only a very small portion of the overall indirect position was sold.
OrbiMed-affiliated entities reported a small open-market sale of Sionna Therapeutics stock under a pre-set trading plan. An entity associated with OrbiMed sold 101 shares of Sionna Therapeutics, Inc. common stock at $44.49 per share on May 27, 2026, in an open-market transaction pursuant to a Rule 10b5-1 plan.
After this sale, OrbiMed-related holdings reported in this filing totaled 2,671,721 shares of common stock, held indirectly through OrbiMed Private Investments VIII, LP. The OrbiMed reporting entities and certain principals disclaim beneficial ownership beyond any pecuniary interest.
Sionna Therapeutics, Inc. director reporting person Peter A. Thompson reported indirect open-market sales of company common stock by an affiliated OrbiMed investment entity. Over three transactions on May 7, 8, and 11, 2026, the entity sold a total of 292,952 shares at prices between $44.58 and $46.22 per share under a pre-arranged Rule 10b5-1 trading plan. The shares are held of record by OrbiMed Private Investments VIII, LP, for which OrbiMed Capital GP VIII LLC and OrbiMed Advisors LLC may be deemed to share voting and investment power. Following these sales, the OrbiMed entity associated with the reporting person continues to hold 2,671,822 shares of Sionna Therapeutics common stock indirectly, with beneficial ownership disclaimed except to the extent of any pecuniary interest.
OrbiMed-affiliated funds reported open-market sales of Sionna Therapeutics, Inc. common stock. OrbiMed-related entity OrbiMed Private Investments VIII, LP sold 48,546 shares on May 7, 2026 at $44.61 per share, 59,767 shares on May 8, 2026 at $44.58 per share, and 184,639 shares on May 11, 2026 at $46.22 per share.
All sales were executed as open-market transactions pursuant to a Rule 10b5-1 trading plan. Following these transactions, the OrbiMed-affiliated holder reported owning 2,671,822 shares of Sionna Therapeutics common stock indirectly.
Sionna Therapeutics director-affiliated entity sells SION shares under 10b5-1 plan
Entities associated with director Peter A. Thompson reported open-market sales of a total of 55,345 shares of Sionna Therapeutics common stock at prices around $44.5 per share over two days. The transactions were executed pursuant to a Rule 10b5-1 trading plan, indicating they were pre-arranged.
The shares are held of record by OrbiMed Private Investments VIII, LP, with OrbiMed Capital GP VIII LLC and OrbiMed Advisors LLC potentially deemed to share voting and investment power. After these sales, OrbiMed’s reported indirect holdings stand at 2,964,774 shares of Sionna Therapeutics common stock, and all reporting parties expressly disclaim beneficial ownership beyond any pecuniary interest.
OrbiMed-affiliated funds reported open-market sales of Sionna Therapeutics, Inc. common stock. OrbiMed-related entities sold 52,397 shares on April 17 at $44.68 per share and 2,948 shares on April 18 at $44.52 per share, under a pre-arranged Rule 10b5-1 trading plan. After these indirect transactions through OrbiMed Private Investments VIII, LP, the reporting entities continued to hold 2,964,774 shares of Sionna Therapeutics common stock.
Sionna Therapeutics, Inc. director Peter A. Thompson reported indirect open-market sales of a total of 510,583 shares of common stock in three transactions. The shares were sold at prices between $44.51 and $45.34 per share pursuant to a Rule 10b5-1 trading plan.
The securities are held of record by OrbiMed Private Investments VIII, LP, an investment fund advised by OrbiMed entities with which Thompson is affiliated. Following these transactions, 3,020,119 shares of common stock remain indirectly held, reflecting a continuing sizable position.
OrbiMed-affiliated funds reported open-market sales of Sionna Therapeutics, Inc. common stock. OrbiMed entities sold a total of 510,583 shares over three days at prices between $44.51 and $45.34 per share under a pre-arranged Rule 10b5-1 trading plan, and continued to hold 3,020,119 shares indirectly after the latest transaction.
The shares are held of record by OrbiMed Private Investments VIII, LP, with OrbiMed Capital GP VIII LLC and OrbiMed Advisors LLC potentially deemed beneficial owners through their control relationships, subject to customary pecuniary-interest and beneficial-ownership disclaimers.
Sionna Therapeutics, Inc. Chief Legal Officer Jennifer Fitzpatrick reported an option exercise and share sale. On March 5, 2026, she exercised a non-qualified stock option for 10,250 shares of common stock at $6.11 per share and immediately sold the same number of shares in an open-market transaction at a weighted average price of $33.8555 per share.
The sale was automatically executed under a Rule 10b5-1 trading plan adopted on June 5, 2025. The shares were sold in multiple trades at prices ranging from $32.56 to $34.83. Following these transactions, she reported 50,935 option shares remaining from this grant and no directly held common shares from this transaction.
Sionna Therapeutics director-affiliated entity records stock sales linked to OrbiMed funds. An investment vehicle, OrbiMed Private Investments VIII, LP, associated with reporting person Peter A. Thompson and OrbiMed Advisors, sold 1,890 shares of Sionna Therapeutics common stock at $44.57 on February 2, 2026.
The same entity sold an additional 29,063 shares at $44.58 on February 3, 2026, leaving 3,530,702 shares of Sionna common stock indirectly beneficially owned after the transactions. The filing notes that the reporting person and related OrbiMed entities disclaim beneficial ownership except to the extent of any pecuniary interest.
OrbiMed-related entities reported insider sales of Sionna Therapeutics common stock. On February 2, 2026, OrbiMed Private Investments VIII, LP sold 1,890 shares at $44.57 per share. On February 3, 2026, it sold an additional 29,063 shares at $44.58 per share.
After these transactions, 3,530,702 shares of Sionna common stock were reported as beneficially owned indirectly. The Form 4 was jointly filed by OrbiMed Advisors LLC and OrbiMed Capital GP VIII LLC, which may be deemed to share voting and investment power through their roles over OrbiMed Private Investments VIII, LP, while each disclaims beneficial ownership except to the extent of any pecuniary interest.
TPG-affiliated investment entities that are 10% owners of Sionna Therapeutics, Inc. reported an indirect sale of 250,000 shares of common stock on January 22, 2026. The shares were sold at a price of $40 per share under transaction code "S," which indicates a sale.
After this transaction, entities associated with the reporting group indirectly held 6,494,962 shares of Sionna common stock through The Rise Fund Sling, L.P. and The Rise Fund Sling II, L.P. The filing explains that the reporting persons may be deemed to beneficially own these securities only to the extent of their direct or indirect pecuniary interests and they expressly disclaim beneficial ownership beyond those economic interests.
Sionna Therapeutics, Inc. reported that its Chief Medical Officer, Charlotte McKee, received a grant of a non-qualified stock option on January 2, 2026. The option covers 155,700 shares of common stock with an exercise price of $39.21 per share and an expiration date of January 1, 2036.
All 155,700 derivative securities are shown as beneficially owned directly following the transaction. According to the footnote, the shares underlying this option vest in 48 equal monthly installments after January 2, 2026, and each monthly vesting is conditioned on McKee’s continued service on the applicable vesting date.
Sionna Therapeutics Chief Business Officer Caroline Stark Beer was granted a non-qualified stock option for 139,340 shares of common stock. The option was awarded on January 2, 2026 with an exercise price of $39.21 per share. All 139,340 derivative securities are reported as directly owned following the transaction.
The shares underlying this option vest in forty-eight equal monthly installments after January 2, 2026, and each monthly vesting requires her continued service on that date. This filing reflects an equity compensation award rather than a sale of existing shares.
Sionna Therapeutics, Inc. (SION) reported insider activity on a Form 4 involving RA Capital–affiliated entities and individuals who are listed as directors and, in some cases, 10% owners. On 11/20/2025 and 11/21/2025, these reporting persons sold multiple small blocks of Sionna common stock in open-market transactions.
The weighted average sale prices ranged from about $39.40 to $40.51 per share, with examples including 9,924 shares sold at a weighted average price of $39.50 and 801 shares sold at a weighted average price of $39.89. After these trades, the reported beneficial holdings for the various RA Capital funds and accounts remained large, such as 6,897,623 shares for one fund and over 2.1 million shares for another, as disclosed in the table.
Sionna Therapeutics (SION) reported insider activity on a Form 4 showing that RA Capital–affiliated entities, which are identified as both directors and 10% owners, sold shares of Sionna common stock over several days. On November 17, 2025, they executed multiple sales, including a sale of 17,913 shares of common stock at a weighted average price of $40.2 per share, in transactions within a price range of $40.00 to $40.85.
Additional sales took place on November 17–19, 2025 at weighted average prices described in the footnotes as ranging from $39.40 to $42.13 per share, all through various RA Capital funds and accounts. The filing notes that detailed breakdowns of the individual trade prices within each range are available upon request, and that the RA Capital entities and individuals disclaim beneficial ownership beyond their economic interest.
Sionna Therapeutics (SION): RA Capital–affiliated reporting persons disclosed open‑market sales of common stock. Trades occurred on 10/24/2025 at $39.50 and on 10/28/2025 at a weighted average price of $39.58, with individual transactions ranging from $39.50 to $39.81.
Following the 10/28 transactions, indirect holdings reported included 6,905,625 shares (RA Capital Healthcare Fund, L.P.) and 715,988 shares (RA Capital Nexus Fund, L.P.), plus 2,240,708 shares (Nexus Fund III) and 209,391 shares (a separately managed account). The filing identifies the reporting persons as Director and 10% Owner where indicated, and notes that a partner of the adviser serves on the board.