SION Investor Alert: Levi & Korsinsky Notifies Investors of Investigation Into Sionna Therapeutics (SION)

Sionna Therapeutics shares lost roughly $40 per share after SION-719 Phase 2a readout, cutting the stock by about 90%. Levi & Korsinsky is investigating potential securities law violations on behalf of investors who lost money.

NEW YORK--(BUSINESS WIRE)--Roughly 90% of Sionna Therapeutics (SION) market value was erased after the Company released Phase 2a PreciSION CF results for SION-719, representing a decline of approximately $40 per share from the stock’s recent trading levels. If you held SION shares and suffered a loss, you are encouraged to click here to submit your information. You may also contact Joseph E. Levi, Esq. via email at [e-mail] or by telephone at [phone].

The impact on shareholders was driven by the clinical readout. SION-719, when added to standard of care, produced a placebo-adjusted sweat chloride change of -1.0 mmol/L, with a p-value of 0.7. Sionna stated it would not advance SION-719 as an add-on therapy.

The loss was not tied to an apparent liquidity shortfall. Sionna reported approximately $268.3 million in cash, cash equivalents and marketable securities as of June 30, 2026, and a second-quarter 2026 net loss of $29.9 million, with cash expected to fund operations into 2028. Shares nonetheless traded in the mid-$40s as recently as July 2026 before the readout.

Investors who lost money on Sionna Therapeutics may have their losses reviewed at no cost. You may also contact Joseph E. Levi, Esq. via email at [e-mail] or by telephone at [phone].

Levi & Korsinsky, LLP -- Top 50 securities litigation firm (ISS, seven consecutive years). Over 70 professionals. Hundreds of millions recovered.

Frequently Asked Questions About the SION Investigation

Q: How much did SION stock drop? A: Shares fell approximately 90%, a decline of roughly $40 per share, after the Company disclosed that the Phase 2a PreciSION CF trial of SION-719 failed to achieve its key activity endpoint for sweat chloride reduction and that the candidate would not advance as an add-on therapy. Investors who purchased shares and suffered losses may be eligible to seek recovery.

Q: Who is eligible to participate in the SION investigation? A: Investors who purchased SION stock or securities and suffered financial losses may be eligible. Eligibility is based on purchase date and documented losses -- not on whether you still hold the shares.

Q: Who is conducting the SION investigation? A: Levi & Korsinsky, LLP is investigating potential securities fraud claims on behalf of investors who purchased SION securities. The firm is nationally recognized, ranked in the ISS Top 50 for seven consecutive years, and has recovered hundreds of millions of dollars for aggrieved investors.

Q: What do SION investors need to do right now? A: Investors may gather brokerage records showing purchase dates, share quantities, and prices paid. Submit your information for a no-cost, no-obligation evaluation of your potential recovery. No immediate action is required to remain eligible to participate in the investigation.

Q: What documents do I need to participate? A: Brokerage statements or trade confirmations showing purchase dates, share quantities, prices paid, and any subsequent sale dates and prices.

Q: What if I already sold my SION shares -- can I still recover losses? A: Yes. Eligibility is based on when you purchased, not whether you still hold the shares. Investors who bought SION and sold at a loss may still participate in the investigation.

Q: What does it cost me to participate? A: There is no upfront cost to submit your information and review whether you may be eligible to recover. Should you choose to participate in any resulting action, these matters are generally handled on a contingency basis, with any attorneys' fees and expenses subject to court approval.

Q: What if my SION losses are small -- is it still worth contacting a lawyer? A: Yes. There is no minimum loss amount required to participate in the investigation.

Attorney Advertising. Prior results do not guarantee similar outcomes.