Company-reported prevalence

Zeleciment rostudirsen

Overview

Field	Value
Drug	Zeleciment rostudirsen (z-rostudirsen and DYNE-251)
Indication	Duchenne muscular dystrophy
Disease	Duchenne muscular dystrophy (DMD); DMD amenable to exon 51 skipping
Company	Dyne Therapeutics, Inc. (worldwide rights; no licensee or co-development partner identified)
Documents searched	Website pipeline page and DMD page (accessed October 2026); press releases, May 20, 2026, May 26, 2026, July 20, 2026, and July 29, 2026; Form 10-K for 2025 (March 2, 2026); Form 10-K for 2024 (February 27, 2025); corporate presentation, July 2026; J.P. Morgan Healthcare Conference presentations, January 2024, January 2025, and January 2026; DELIVER clinical update presentation, September 2024; DELIVER topline results presentation, December 8, 2025
Data as of	October 14, 2026
Prepared by	AI research agent (Claude); not yet reviewed by a person

Company statements of prevalence

United States

Number affected: Dyne Therapeutics website, October 2026

“DMD affects ~12,000 people in the U.S.” (opens the source at this quote in a new tab)

Cited source: None stated in the document.

Dyne Therapeutics (2026) website, pipeline page, quoted passage highlighted — Captured from the passage on the page (opens in a new tab)

Number affected: Dyne Therapeutics Form 10-K for 2025, March 2026

“approximately 12,000 patients in the United States” (opens the source at this quote in a new tab)

Cited source: None stated in the document.

Dyne Therapeutics (2026) Form 10-K for 2025, quoted passage highlighted — Captured from page 11 of 385 (opens in a new tab)

Number affected: Dyne Therapeutics corporate presentation, July 2026

“~12,000 US DMD population” (opens the source at this quote in a new tab)

Cited source: None stated in the document.

Dyne Therapeutics (2026) corporate presentation, July 2026, quoted passage highlighted — Captured from page 30 of 60 (opens in a new tab)

Number affected: Dyne Therapeutics press release, July 2026

“affecting approximately 12,000 individuals in the U.S.” (opens the source at this quote in a new tab)

Cited source: None stated in the document.

Dyne Therapeutics (2026) press release, July 20, 2026, quoted passage highlighted — Captured from the passage on the page (opens in a new tab)

Eligible population: Dyne Therapeutics corporate presentation, July 2026

“~1,600 US Exon 51 skip amenable DMD” (opens the source at this quote in a new tab)

Cited source: None stated in the document.

Prevalence (share of exon 51 skip amenable patients treated with a disease-modifying therapy): Dyne Therapeutics corporate presentation, July 2026

“>50%” (opens the source at this quote in a new tab)
“Exon 51 skip amenable patients have been treated with a disease modifying therapy” (opens the source at this quote in a new tab)

Cited source: 2.2 Dyne Therapeutics 2026

Number affected: Dyne Therapeutics Form 10-K for 2024, February 2025

“approximately 12,000 to 15,000 patients in the United States” (opens the source at this quote in a new tab)

Cited source: None stated in the document.

Dyne Therapeutics (2025) Form 10-K for 2024, quoted passage highlighted — Captured from page 15 of 189 (opens in a new tab)

Number affected: Dyne Therapeutics J.P. Morgan Healthcare Conference presentation, January 2025

“~12,000 - 15,000 (US)” (opens the source at this quote in a new tab)

Cited source: None stated in the document.

Dyne Therapeutics (2025) J.P. Morgan Healthcare Conference presentation, January 2025, quoted passage highlighted — Captured from page 18 of 26 (opens in a new tab)

Europe

Number affected (Europe): Dyne Therapeutics website, October 2026

“~16,000 in the EU.” (opens the source at this quote in a new tab)

Cited source: None stated in the document.

Number affected (Europe): Dyne Therapeutics Form 10-K for 2025, March 2026

“approximately 16,000 patients in Europe, have DMD.” (opens the source at this quote in a new tab)

Cited source: None stated in the document.

Number affected (Europe): Dyne Therapeutics corporate presentation, July 2026

“~16,000 (EU)” (opens the source at this quote in a new tab)

Cited source: None stated in the document.

Number affected (Europe): Dyne Therapeutics press release, July 2026

“and 16,000 in the EU.” (opens the source at this quote in a new tab)

Cited source: None stated in the document.

Number affected (Europe): Dyne Therapeutics Form 10-K for 2024, February 2025

“approximately 25,000 patients in Europe, have DMD.” (opens the source at this quote in a new tab)

Cited source: None stated in the document.

Number affected (Europe): Dyne Therapeutics J.P. Morgan Healthcare Conference presentation, January 2025

“~ 25,000 (Europe)” (opens the source at this quote in a new tab)

Cited source: None stated in the document.

Global

No evidence found.

Other countries and regions

No evidence found.

Geography not stated

Birth prevalence: Dyne Therapeutics Form 10-K for 2025, March 2026

“We estimate that DMD occurs in approximately one in every 3,500 to 5,000 live male births” (opens the source at this quote in a new tab)

Cited source: None stated in the document.

Prevalence (share of DMD amenable to exon 51 skipping): Dyne Therapeutics corporate presentation, July 2026

“~ 13% is exon 51 skip amenable” (opens the source at this quote in a new tab)

Cited source: 2.1 Aartsma-Rus 2009

Prevalence (share of DMD amenable to exon skipping): Dyne Therapeutics Form 10-K for 2025, March 2026

“Approximately 80% of patients with DMD have DMD mutations amenable to exon skipping in the nucleus.” (opens the source at this quote in a new tab)

Cited source: None stated in the document.

Sources the company cites

Aartsma-Rus 2009

Reference as the company lists it

“Aartsma-Rus et al. Hum Mutat. 2009;30:293-299” (opens the source at this quote in a new tab)

Passage carrying the figure

“Exon 51 skipping, which is being tested in clinical trials, would be applicable to the largest group (13%) of all DMD patients.” (opens the source at this quote in a new tab)

Aartsma-Rus 2009, quoted passage highlighted — Captured from the passage on the page (opens in a new tab)

Dyne therapeutics 2026

Reference as the company lists it

“Based on analysis of claims data.” (opens the source at this quote in a new tab)

Passage carrying the figure

Not quoted: The footnote names no published document; the company's analysis of claims data is not public.

Zeleciment rostudirsen (z-rostudirsen)