Dyne Therapeutics Announces Proposed Public Offering of Common Stock

Rhea-AI Summary

Dyne Therapeutics (Nasdaq: DYN) announced on Dec 8, 2025 that it commenced an underwritten public offering of $300,000,000 of common stock with a 30-day option for underwriters to purchase up to an additional $45,000,000 of shares.

All shares in the proposed offering are to be sold by Dyne. The offering is subject to market and other conditions and will be made pursuant to a Form S-3 shelf registration filed on March 5, 2024. Morgan Stanley, Jefferies, Stifel and Guggenheim Securities are joint book-running managers. A preliminary prospectus supplement is expected to be filed with the SEC and final terms will appear in a final prospectus supplement.

Positive

• Primary raise of $300,000,000 announced
• Up to $345,000,000 available including underwriter option

Negative

• All offered shares are company shares, implying shareholder dilution
• Offering completion is conditional on market and other factors

Key Figures

Base offering size $300,000,000 Proposed underwritten public offering of common stock

Underwriters’ option $45,000,000 30‑day option to purchase additional common stock

Option period 30 days Duration of underwriters’ option for additional shares

Shelf filing date March 5, 2024 Form S‑3 registration statement filing date cited in the release

Market Reality Check

$22.20 Last Close

Volume Volume 2,571,519 is 9% above the 20‑day average of 2,357,527, indicating elevated interest ahead of the offering. normal

Technical Shares at $20.28 are trading above the 200‑day MA of $13.11, despite being 31.75% below the 52‑week high.

Peers on Argus

Peers show mixed moves: SRPT -2.73%, IMCR -3.22%, PROK -8.95%, while MESO +1.77% and HRMY +4.08%. DYN’s pre‑news decline of 2.27% appears more stock‑specific around the offering.

Historical Context

Date	Event	Sentiment	Move	Catalyst
Nov 05	Earnings and update	Neutral	-2.9%	Quarterly results and pipeline timelines, including DELIVER and ACHIEVE updates.
Nov 03	Investor conferences	Positive	+6.8%	Multiple upcoming healthcare conference presentations and webcasts announced.
Oct 06	Clinical data update	Positive	-3.1%	One‑year Phase 1/2 ACHIEVE data showing functional improvement in DM1.
Oct 02	Board appointment	Positive	+4.1%	Appointment of experienced executive Brian Posner to the Board of Directors.
Sep 29	Regulatory designation	Positive	-5.9%	Japanese Orphan Drug designation for DYNE‑251 with potential 10‑year exclusivity.

Pattern Detected

Recent history shows occasional sell‑offs on positive clinical and regulatory milestones, and modest pressure around financing events.

Recent Company History

Over the last few months, Dyne reported Q3 2025 results with cash of $791.9M and an expected runway into Q3 2027, alongside multiple Breakthrough Therapy Designations. It has highlighted key upcoming data in DELIVER and ACHIEVE and added an experienced director as it prepares for potential launches around 2027–2028. Clinical updates for DYNE‑101 and DYNE‑251 have been generally positive, though share reactions have sometimes been negative. Today’s proposed offering follows prior 2025 financings that strengthened liquidity.

Market Pulse Summary

This announcement details a proposed underwritten public offering of $300,000,000 of Dyne’s common stock, with a 30‑day option for underwriters to purchase up to an additional $45,000,000. It follows earlier 2025 equity financings that bolstered liquidity as the company advances DYNE‑251 and DYNE‑101 toward key data and potential filings. Investors may watch for the final prospectus terms, total capital raised, and how this fits with the cash runway already disclosed in recent SEC filings.

Key Terms

underwritten public offering financial

"today announced that it has commenced an underwritten public offering of $300,000,000"

An underwritten public offering is when a company sells new shares of its stock to the public with the help of a financial firm, called an underwriter. The underwriter agrees to buy all the shares upfront, reducing the company's risk, and then sells them to investors. This process helps companies raise money quickly and confidently from a wide range of buyers.

prospectus supplement regulatory

"This offering will be made only by means of a prospectus supplement and accompanying prospectus"

A prospectus supplement is an additional document provided alongside a company's main offering details, offering updated or extra information about a specific financial product being sold. It helps investors understand the latest terms, risks, and details of the investment, similar to how an update or revision clarifies or expands on original instructions, ensuring they have current and complete information before making a decision.

registration statement regulatory

"form a part of the registration statement. A preliminary prospectus supplement"

A registration statement is a formal document that companies file with a government agency to offer new shares of stock to the public. It provides essential information about the company's finances, operations, and risks, helping investors make informed decisions. Think of it as a detailed product description that ensures transparency and trust before buying into a company.

form s-3 regulatory

"pursuant to a shelf registration statement on Form S-3 that was previously filed"

Form S-3 is a legal document companies use to register their stock sales with the government, making it easier and faster for them to raise money by selling shares to investors. It’s like having a pre-approved shopping list that lets a company quickly sell new shares when they need funds, without going through a lengthy approval process each time.

AI-generated analysis. Not financial advice.

WALTHAM, Mass., Dec. 08, 2025 (GLOBE NEWSWIRE) -- Dyne Therapeutics, Inc. (Nasdaq: DYN), a clinical-stage company focused on delivering functional improvement for people living with genetically driven neuromuscular diseases, today announced that it has commenced an underwritten public offering of $300,000,000 of shares of its common stock. Dyne also intends to grant the underwriters a 30-day option to purchase up to an additional $45,000,000 of shares of its common stock. All of the shares in the proposed offering are to be sold by Dyne.

Morgan Stanley, Jefferies, Stifel and Guggenheim Securities are acting as joint book-running managers for the offering. The proposed offering is subject to market and other conditions, and there can be no assurance as to whether or when the offering may be completed, or as to the actual size or terms of the offering.

The proposed offering is being made pursuant to a shelf registration statement on Form S-3 that was previously filed with the Securities and Exchange Commission (“SEC”) on March 5, 2024 and became automatically effective upon filing. This offering will be made only by means of a prospectus supplement and accompanying prospectus that form a part of the registration statement. A preliminary prospectus supplement relating to and describing the terms of the offering is expected to be filed with the SEC and, if and when filed, copies of the preliminary prospectus supplement relating to the offering may be obtained for free by visiting the SEC’s website at www.sec.gov. Copies of the preliminary prospectus supplement and the accompanying prospectus may also be obtained by contacting: Morgan Stanley & Co. LLC, Attention: Prospectus Department, 180 Varick Street, 2nd Floor, New York, NY 10014, or by email at prospectus@morganstanley.com; Jefferies LLC, Attention: Equity Syndicate Prospectus Department, 520 Madison Avenue, New York, NY 10022, by telephone at (877) 821-7388, or by email at Prospectus_Department@Jefferies.com; Stifel, Nicolaus & Company, Incorporated, Attention: Prospectus Department, One Montgomery Street, Suite 3700, San Francisco, CA 94104, by telephone at (415) 364-2720 or by email at syndprospectus@stifel.com; or Guggenheim Securities, LLC, Attention: Equity Syndicate Department, 330 Madison Avenue, 8th Floor, New York, NY 10017, by telephone at (212) 518-9544, or by email at GSEquityProspectusDelivery@guggenheimpartners.com. The final terms of the offering will be disclosed in a final prospectus supplement to be filed with the SEC.

This press release shall not constitute an offer to sell, or a solicitation of an offer to buy these securities, nor shall there be any sale of these securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction.

About Dyne Therapeutics

Dyne Therapeutics is focused on delivering functional improvement for people living with genetically driven neuromuscular diseases. We are developing therapeutics that target muscle and the central nervous system (CNS) to address the root cause of disease. The company is advancing clinical programs for myotonic dystrophy type 1 (DM1) and Duchenne muscular dystrophy (DMD), and preclinical programs for facioscapulohumeral muscular dystrophy (FSHD) and Pompe disease. At Dyne, we are on a mission to deliver functional improvement for individuals, families and communities.

Forward-Looking Statements  

This press release contains forward-looking statements that involve substantial risks and uncertainties. All statements, other than statements of historical facts, contained in this press release, including statements relating to the proposed underwritten public offering, the anticipated terms of the proposed offering, market and other conditions relating to the offering, constitute forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “might,” “objective,” “ongoing,” “plan,” “predict,” “project,” “potential,” “should,” or “would,” or the negative of these terms, or other comparable terminology are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Dyne may not actually achieve the plans, intentions or expectations disclosed in these forward-looking statements, and you should not place undue reliance on these forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in these forward-looking statements as a result of various important factors, including: the uncertainties related to market conditions and the completion of the public offering on the anticipated terms or at all and other factors discussed in the “Risk Factors” section of the preliminary prospectus supplement to be filed with the SEC, as well as the risks and uncertainties identified in Dyne’s filings with the SEC, including Dyne’s most recent Form 10-Q and in subsequent filings Dyne may make with the SEC. In addition, the forward-looking statements included in this press release represent Dyne’s views as of the date of this press release. Dyne anticipates that subsequent events and developments will cause its views to change. However, while Dyne may elect to update these forward-looking statements at some point in the future, it specifically disclaims any obligation to do so. These forward-looking statements should not be relied upon as representing Dyne’s views as of any date subsequent to the date of this press release.

Contacts:

Investors

Mia Tobias
ir@dyne-tx.com
781-317-0353

Media

Stacy Nartker
snartker@dyne-tx.com
781-317-1938

FAQ

What size offering did Dyne Therapeutics (DYN) announce on Dec 8, 2025?

Dyne announced an underwritten offering of $300,000,000 of common stock with a 30-day option for up to an additional $45,000,000.

Who are the joint book-running managers for Dyne's (DYN) Dec 2025 offering?

Morgan Stanley, Jefferies, Stifel and Guggenheim Securities are acting as joint book-running managers.

Is Dyne's (DYN) Dec 8, 2025 offering being sold by insiders or the company?

All of the shares in the proposed offering are to be sold by Dyne (the company), not third parties.

What registration allows Dyne (DYN) to conduct the Dec 2025 offering?

The offering is being made under a shelf registration on Form S-3 that was filed on March 5, 2024 and became automatically effective.

Where can investors find Dyne's (DYN) preliminary prospectus supplement for the offering?

A preliminary prospectus supplement is expected to be filed with the SEC and can be obtained for free via www.sec.gov when filed.