Why DYN Shares Are Down 10% After-Hours? Day After An FDA Win, Another Announcement Rocks Stock

Dyne Therapeutics announced plans to raise $300 million through a public stock offering on Tuesday.

• The announcement comes a day after the company announced that the U.S. Food and Drug Administration has accepted its application seeking approval for its experimental therapy z-rostudirsen. 
• Net proceeds will support ongoing clinical development and regulatory work for z-rostudirsen and z-basivarsen, among other needs. 
• As of March 31, Dyne held $972.2 million in cash, cash equivalents, and marketable securities.

Shares of Dyne Therapeutics (DYN) fell around 10% in after-hours trading on Tuesday after the company announced plans to raise $300 million through a public stock offering.

The announcement comes a day after the company announced that the U.S. Food and Drug Administration has accepted its application seeking approval for its experimental therapy z-rostudirsen in the treatment of Duchenne muscular dystrophy.

Capital Raise

Dyne said it has started an underwritten public offering of $300 million in common stock. The company also granted underwriters a 30-day option to buy up to an additional $45 million in shares. All shares will be sold by Dyne. The offering is subject to market conditions and has not yet been priced.

On Monday, the FDA accepted the company’s Biologics License Application for z-rostudirsen, its experimental treatment for Duchenne muscular dystrophy patients. The agency granted the application Priority Review and set a target decision date of January 21, 2027. Dyne has said it expects a potential U.S. launch in early 2027 if approved.

The company also recently started two global late-stage trials, the FORZETTO study for z-rostudirsen in May and the HARMONIA study for z-basivarsen in myotonic dystrophy type 1 in March. The company also has four preclinical candidates in its pipeline and early programs in facioscapulohumeral muscular dystrophy (FSHD) and Pompe disease.

Cash Position And Use of Proceeds

As of March 31, Dyne held $972.2 million in cash, cash equivalents, and marketable securities. Combined with the new offering and a $50 million debt draw completed in June, the company expects the proceeds to fund operations into the second quarter of 2028.

Net proceeds will support ongoing clinical development and regulatory work for z-rostudirsen and z-basivarsen, manufacturing scale-up, and commercial infrastructure ahead of a potential launch.

How Did DYN Retail Traders React?

On Stocktwits, retail sentiment around DYN stayed within ‘bullish’ levels, accompanied by ‘high’ levels of chatter.

A Stocktwits user sounded concerns about the company’s market capitalization, highlighting that it has no approved therapies.

DYN stock has gained 22% year-to-date. 

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