Sionna Therapeutics, INC Schedule 13D activist filings

RA Capital Management and affiliated entities have significantly reduced their holdings in Sionna Therapeutics, selling over 3.4 million shares.

OrbiMed Advisors and OrbiMed Capital GP VIII have reduced their beneficial ownership in Sionna Therapeutics, Inc. by selling shares via a 10b5-1 plan.

RA Capital Management and its affiliates report a dilution of their beneficial ownership in Sionna Therapeutics, Inc. to 22.6% of common stock outstanding.

Atlas Venture entities have reduced their collective beneficial ownership in Sionna Therapeutics, Inc. to 7.0% through recent share sales.

TPG GP A, LLC and its principals, James G. Coulter and Jon Winkelried, have disclosed a significant 15.2% beneficial ownership in Sionna Therapeutics, Inc. following the company's recent Initial Public Offering.

Atlas Venture entities have filed a Schedule 13D, revealing a collective 8.4% beneficial ownership in Sionna Therapeutics, primarily acquired prior to and during the company's recent initial public offering.

RA Capital Management and its affiliates have filed a Schedule 13D, revealing a significant 23.7% beneficial ownership in Sionna Therapeutics, Inc. common stock following the company's recent Initial Public Offering.

Enavate Sciences GP, LLC and Sionna Aggregator, LP have disclosed a 5.6% beneficial ownership stake in Sionna Therapeutics, Inc. following the company's initial public offering.

OrbiMed Advisors LLC and OrbiMed Capital GP VIII LLC have filed a Schedule 13D, revealing a beneficial ownership of 8.4% of Sionna Therapeutics, Inc.'s common stock, acquired through pre-IPO investments and participation in the initial public offering.