Sionna Therapeutics, Inc. (SION) Shareholders Who Lost Money – Contact Law Offices of Howard G. Smith About Securities Fraud Investigation

Law Offices of Howard G. Smith announces an investigation on behalf of Sionna Therapeutics, Inc. (“Sionna” or the “Company”) (NASDAQ: SION) investors concerning the Company’s possible violations of federal securities laws.

IF YOU ARE AN INVESTOR WHO SUFFERED A LOSS IN SIONNA THERAPEUTICS, INC. (SION), CONTACT THE LAW OFFICES OF HOWARD G. SMITH ABOUT POTENTIALLY PURSUING CLAIMS TO RECOVER YOUR LOSS.

Contact the Law Offices of Howard G. Smith to discuss your legal rights by email at howardsmith@howardsmithlaw.com, by telephone at (215) 638-4847 or visit our website at www.howardsmithlaw.com.

What Happened?

On August 10, 2026, Sionna reported topline data from its PreciSION CF Phase 2a trial and provided a corporate update. Among other items, Sionna announced a primary endpoint miss and that the Company will not advance SION-719 as an add-on to standard of care.

On this news, Sionna’s stock fell $46.54, or 91.2% per share, to close at $4.10 per share on August 10, 2026, thereby injuring investors.

Contact Us To Participate or Learn More:

If you purchased Sionna Therapeutics, Inc. securities, have information or would like to learn more about these claims, or have any questions concerning this announcement or your rights or interests with respect to these matters, please contact us:

Law Offices of Howard G. Smith

3070 Bristol Pike, Suite 112

Bensalem, Pennsylvania 19020

Telephone: (215) 638-4847

Email: howardsmith@howardsmithlaw.com

Visit our website at: www.howardsmithlaw.com.

This press release may be considered Attorney Advertising in some jurisdictions under the applicable law and ethical rules.

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