Dyne Therapeutics Inc at Morgan Stanley Global Healthcare Conference Transcript

The following is excerpted from the question-and-answer section of the transcript.

Question: Michael Ulz - Morgan Stanley - Analyst : So a lot to look forward to and maybe we could just start with the platform because that's sort of the base and what's driving all your discoveries here. So maybe talk a little bit about FORCE platform and why it's well set?

Question: Michael Ulz - Morgan Stanley - Analyst : Maybe we can switch into sort of your -- one of your programs DNY 101 (sic) [DYNE-101] for DM1. And maybe to start there, just talk a little bit about why target DM1, what sort of makes it an attractive market opportunity?

Question: Michael Ulz - Morgan Stanley - Analyst : Got you. That's a nice sort of segue into sort of what you're seeing in the clinic now from the ACHIEVE study. You've given us a couple of updates. So maybe just what are the key takeaways or what have you learned so far from that study?

Question: Michael Ulz - Morgan Stanley - Analyst : Maybe talk about sort of the registrational cohort and you've made some fine-tuning on the strategy there. So maybe walk us through that a little bit.

Question: Michael Ulz - Morgan Stanley - Analyst : Makes sense. And you spoke to the FDA and then you filed the protocol amendment? Have you gotten feedback or acceptance from the FDA there? Are there any next steps around that at all? Or is that all done?

Question: Michael Ulz - Morgan Stanley - Analyst : And maybe just back to the registrational cohort. You have data mid mid-next year and for approval? Is it just hitting the primary endpoint on vHOT? Or are these other endpoints important to you to sort of build the story or how do you think about that?

Question: Michael Ulz - Morgan Stanley - Analyst : Got you. And I guess one question we get sometimes from investors is your competitors using vHOT as a primary endpoint as well. They have more patients than you do in your sort of registrational cohort. And so is there any risk around that or not, I guess? REFINITIV STREETEVENTS | www.refinitiv.com | Contact Us consent of Refinitiv. 'Refinitiv' and the Refinitiv logo are registered trademarks of Refinitiv and its affiliated companies. SEPTEMBER 08, 2025 / 1:15PM, DYN.OQ - Dyne Therapeutics Inc at Morgan Stanley Global Healthcare Conference

Question: Michael Ulz - Morgan Stanley - Analyst : Maybe talk a little bit about how enrollment is going in the expansion cohort versus your expectations?

Question: Michael Ulz - Morgan Stanley - Analyst : You just mentioned the confirmatory study to start in the first quarter of next year. Maybe just talk a little bit about sort of your thoughts on the study design and kind of what that could look like in terms of endpoints, et cetera.

Question: Michael Ulz - Morgan Stanley - Analyst : In terms of timing of the endpoints, is 12 months a reasonable expectation? Or is it -- could it be 6 months?

Question: Michael Ulz - Morgan Stanley - Analyst : That makes sense. And maybe a couple of questions just on the competitor front. Obviously, there's one competitor out there, they're in Phase III and points of differentiation. You've mentioned some already like splicing, anything else come in mind?

Question: Michael Ulz - Morgan Stanley - Analyst : Makes sense. And another question we get is just implications of having sort of an accelerated approval when a competitor may have sort of a full approval at the same time and how you think about that?

Question: Michael Ulz - Morgan Stanley - Analyst : Makes sense. REFINITIV STREETEVENTS | www.refinitiv.com | Contact Us consent of Refinitiv. 'Refinitiv' and the Refinitiv logo are registered trademarks of Refinitiv and its affiliated companies. SEPTEMBER 08, 2025 / 1:15PM, DYN.OQ - Dyne Therapeutics Inc at Morgan Stanley Global Healthcare Conference

Question: Michael Ulz - Morgan Stanley - Analyst : I guess just for the last question on DM1 program as you progress to sort of starting the Phase III 1Q of next year and data 2Q? Or are there any other sort of updates we should be paying attention to from now until mid next year.

Question: Michael Ulz - Morgan Stanley - Analyst : Yes.

Question: Michael Ulz - Morgan Stanley - Analyst : You guys will be busy for sure,

Question: Michael Ulz - Morgan Stanley - Analyst : Maybe we can dig into just sort of the DMD program and 251 and maybe just start, let's talk about sort of unmet need and sort of market opportunity there. REFINITIV STREETEVENTS | www.refinitiv.com | Contact Us consent of Refinitiv. 'Refinitiv' and the Refinitiv logo are registered trademarks of Refinitiv and its affiliated companies. SEPTEMBER 08, 2025 / 1:15PM, DYN.OQ - Dyne Therapeutics Inc at Morgan Stanley Global Healthcare Conference

Question: Michael Ulz - Morgan Stanley - Analyst : Yeah, maybe just talk a little bit about you expect to provide the sort of registrational cohort data by the end of this year and kind of what's the focus there? And what's your level of confidence?

Question: Michael Ulz - Morgan Stanley - Analyst : You mentioned sort of continued confidence in the accelerated path. Just curious if you've had any interactions with the FDA just given sort of the new leadership and just any issues there? REFINITIV STREETEVENTS | www.refinitiv.com | Contact Us consent of Refinitiv. 'Refinitiv' and the Refinitiv logo are registered trademarks of Refinitiv and its affiliated companies. SEPTEMBER 08, 2025 / 1:15PM, DYN.OQ - Dyne Therapeutics Inc at Morgan Stanley Global Healthcare Conference

Question: Michael Ulz - Morgan Stanley - Analyst : Makes sense. Since you could be in a position to maybe launch this maybe end of next year, maybe talk a little bit about sort of plans there, where you're at and sort of preparing ahead of that?

Question: Michael Ulz - Morgan Stanley - Analyst : Are there other Exon 51 skippers in development you are aware?

Question: Michael Ulz - Morgan Stanley - Analyst : And just given the platform and your -- the data you're seeing in Exon 51. How are you thinking about other potential Exon skippers and thoughts about moving those forward in time lines maybe?

Question: Michael Ulz - Morgan Stanley - Analyst : Maybe just talk a little bit about just the commercial opportunity there, but also sort of leveraging that for DM1. Are there synergies there that could sort of be helpful?

Question: Michael Ulz - Morgan Stanley - Analyst : It Makes sense. And we got two minutes left. So maybe just last question, just FSHD and just remind us where you are with that program and next steps.

Question: Michael Ulz - Morgan Stanley - Analyst : Okay. Great. We're just about out of time. So a lot to look forward to. Appreciate your time, John and Erick, and thanks so much. REFINITIV STREETEVENTS | www.refinitiv.com | Contact Us consent of Refinitiv. 'Refinitiv' and the Refinitiv logo are registered trademarks of Refinitiv and its affiliated companies. SEPTEMBER 08, 2025 / 1:15PM, DYN.OQ - Dyne Therapeutics Inc at Morgan Stanley Global Healthcare Conference