Dyne Therapeutics to Host Investor Conference Call and Webcast to Review Topline Results from Registrational Expansion Cohort (REC) of DELIVER Clinical Trial of Z-Rostudirsen (DYNE-251) in Duchenne Muscular Dystrophy; Tomorrow, December 8 at 8:00 a.m. ET

Rhea-AI Summary

Dyne Therapeutics (Nasdaq: DYN) will announce topline results from the Registrational Expansion Cohort (REC) of the Phase 1/2 DELIVER trial of zeleciment rostudirsen (z-rostudirsen, DYNE-251) on December 8, 2025.

The company will host an investor conference call and webcast at 8:00 a.m. ET on that day; a press release will be issued before the event. The webcast and an accompanying slide presentation will be available on Dyne’s Events & Presentations page, and a replay will be accessible for 90 days after the presentation.

News Market Reaction – DYN

+9.47%

4 alerts

+9.47% News Effect

+13.2% Peak Tracked

-16.9% Trough Tracked

+$251M Valuation Impact

$2.90B Market Cap

0.0x Rel. Volume

On the day this news was published, DYN gained 9.47%, reflecting a notable positive market reaction. Argus tracked a peak move of +13.2% during that session. Argus tracked a trough of -16.9% from its starting point during tracking. Our momentum scanner triggered 4 alerts that day, indicating moderate trading interest and price volatility. This price movement added approximately $251M to the company's valuation, bringing the market cap to $2.90B at that time.

Data tracked by StockTitan Argus on the day of publication.

Key Figures

Topline data date: December 8, 2025 Call time: 8:00 a.m. ET Webcast replay period: 90 days

3 metrics

Topline data date December 8, 2025 DELIVER REC topline results release date

Call time 8:00 a.m. ET Investor conference call and webcast start time

Webcast replay period 90 days Replay availability after the investor presentation

Market Reality Check

Price: $16.09 Vol: Volume 2,571,519 is 1.09x...

normal vol

$16.09 Last Close

Volume Volume 2,571,519 is 1.09x the 20-day average of 2,357,527, showing modestly elevated trading before the data event. normal

Technical Shares at $20.28 are trading above the 200-day MA of $13.11, reflecting a pre-existing uptrend into the REC topline.

Peers on Argus

DYN fell 2.27% while close peers were mixed: SRPT -2.73%, IMCR -3.22%, PROK -8.9...

1 Up

DYN fell 2.27% while close peers were mixed: SRPT -2.73%, IMCR -3.22%, PROK -8.95%, MESO +1.77%, HRMY +4.08%. Moves do not point to a unified sector trend.

Historical Context

5 past events · Latest: Nov 05 (Positive)

Pattern 5 events

Date	Event	Sentiment	Move	Catalyst
Nov 05	Earnings and pipeline	Positive	-2.9%	Q3 2025 results, cash runway and timelines for DYNE-251 and DYNE-101.
Nov 03	Investor conferences	Neutral	+6.8%	Announcements of multiple healthcare conference presentations and webcasts.
Oct 06	Clinical data update	Positive	-3.1%	One-year ACHIEVE Phase 1/2 data for DYNE-101 showing functional gains.
Oct 02	Board appointment	Positive	+4.1%	Appointment of experienced executive Brian Posner to the board.
Sep 29	Regulatory designation	Positive	-5.9%	Japanese Orphan Drug designation for DYNE-251 and recap of DELIVER data.

Pattern Detected

Clinically and regulatory positive news has often been followed by negative next-day moves, while management and conference updates have seen more supportive price action.

Recent Company History

Over the last few months, Dyne reported Q3 2025 results with cash of $791.9M and runway into Q3 2027, plus expectations for DELIVER REC topline in Dec 2025, yet the stock fell 2.88%. Positive ACHIEVE one-year data and Japanese Orphan Drug designation for DYNE-251 also coincided with declines of 3.14% and 5.93%. In contrast, a board appointment on Oct 2 and investor conference announcements in early November saw gains. Today’s announcement of a REC topline review call fits into this pattern of major clinical and regulatory milestones drawing focused investor attention.

Market Pulse Summary

The stock moved +9.5% in the session following this news. A strong positive reaction aligns with the...

Analysis

The stock moved +9.5% in the session following this news. A strong positive reaction aligns with the stock’s history of sizable moves around data‑centric and conference announcements, where prior same‑tag events averaged about 17.74% in magnitude. However, earlier positive clinical and regulatory updates sometimes saw next‑day declines, underscoring the risk that enthusiasm could fade once topline REC details are fully digested. Investors monitoring sustainability would likely watch how results compare to prior DELIVER data and whether trading remains above the 200-day MA of $13.11 after initial volatility.

Key Terms

registrational expansion cohort, phase 1/2, clinical trial, webcast

4 terms

registrational expansion cohort medical

"topline clinical results from the Registrational Expansion Cohort (REC) of the Phase 1/2 DELIVER trial"

A registrational expansion cohort is a larger, focused group added to a clinical trial to gather the specific safety and effectiveness data regulators need to decide on drug approval. Think of it as a final test drive with more drivers and clearer goals so regulators can judge whether the treatment works for a defined patient group. For investors, its start, progress, or outcome can materially change a drug’s approval odds and a company’s value.

phase 1/2 medical

"from the Registrational Expansion Cohort (REC) of the Phase 1/2 DELIVER trial"

Phase 1/2 is a combined early-stage clinical trial that first tests a new drug or treatment for safety and the right dose, then quickly expands to check if it shows any signs of working in patients. For investors, results from a Phase 1/2 study offer an early read on both risk and potential reward—like a prototype test that both confirms a product won’t harm users and suggests whether it could sell—helping guide valuation and development decisions.

clinical trial medical

"DELIVER Clinical Trial of Z-Rostudirsen (DYNE-251) in Duchenne Muscular Dystrophy"

A clinical trial is a carefully controlled study in which a new medicine, medical device, or treatment is tested on people to see if it is safe and effective. For investors it matters because trial results determine whether a product can win regulatory approval and reach patients, much like a road test decides if a new car can be sold; positive or negative results can sharply change a company’s prospects and stock value.

webcast technical

"to host a webcast at 8:00 a.m. ET"

A webcast is a live or recorded online event where people watch or listen to presentations, announcements, or performances through the internet. It’s like a TV broadcast but over the internet, allowing viewers from anywhere to tune in in real time or later. Webcasts are important because they let companies share information quickly and widely with audiences around the world.

AI-generated analysis. Not financial advice.

WALTHAM, Mass., Dec. 07, 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 plans to announce topline clinical results from the Registrational Expansion Cohort (REC) of the Phase 1/2 DELIVER trial of zeleciment rostudirsen (z-rostudirsen, also known as DYNE-251) on December 8, 2025, and to host a webcast at 8:00 a.m. ET. The company intends to issue a press release prior to the start of the event.

Investor Conference Call and Webcast
The webcast will be available on the Events & Presentations page of the Investors & Media section of Dyne’s website, and a replay will be accessible for 90 days following the presentation. An accompanying slide presentation will also be available. To view the webcast and replay, please visit https://investors.dyne-tx.com/news-and-events/events-and-presentations.

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. Learn more at https://www.dyne-tx.com/ and follow us on X, LinkedIn and Facebook.

Contacts:

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

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

FAQ

When will Dyne Therapeutics (DYN) announce topline REC results from the DELIVER trial?

Dyne will announce topline REC results on December 8, 2025.

What time is the Dyne Therapeutics (DYN) investor webcast for DELIVER REC results?

The investor webcast and conference call are scheduled for 8:00 a.m. ET on December 8, 2025.

Where can investors watch the Dyne (DYN) DELIVER REC results webcast and access slides?

The webcast and slide presentation will be on Dyne’s Events & Presentations page at https://investors.dyne-tx.com/news-and-events/events-and-presentations.

Will Dyne (DYN) provide a press release before the DELIVER webcast?

Yes, the company intends to issue a press release prior to the start of the webcast.

How long will the replay of Dyne’s (DYN) DELIVER presentation be available?

A replay will be accessible for 90 days following the presentation.

What drug and trial does Dyne (DYN) plan to report REC topline results for on December 8, 2025?

Dyne plans to report REC topline results for zeleciment rostudirsen (z-rostudirsen, DYNE-251) from the Phase 1/2 DELIVER trial.