| --- | --- | --- | |-------|-------|-------| | | | | | | | | Forward-Looking Statements This presentation contains forward-looking statements that involve substantial risks and uncertainties. All statements, other than statements of historical facts, contained in this presentation, including statements regarding Dyne's strategy, future operations, prospects and plans, objectives of management, the potential of the FORCE platform, the anticipated timelines for reporting data for the DYNE-251 and DYNE-101 tr ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2023 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from ________________ to ________________ Commission File Number: 001-39509 Dyne Therapeutics, Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 3 ...

FORCE Targets Toxic Nuclear DMPK RNA RNaseH1 Approximately 10 Normal DMPK mRNA Normal DMPK mRNA is able to leave the nucleus Toxic DMPK mRNA is unable to leave the nucleus Approximately 10 Toxic DMPK mRNA Toxic DMPK RNA sequesters MBNL and forms foci Nucleus Cell Membrane ASO ASO binds DMPK RNA RNaseH1 cleaves DMPK RNA MBNL is released to restore splicing Cytoplasm in the nucleus Endosome TfR1 FORCE 16 Robust Preclinical Data Supporting the Potential of DYNE-101 to Drive Disease Modification in the Clinic | ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2022 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO Commission File Number: 001-39509 Dyne Therapeutics, Inc. (Exact name of Registrant as specified in its Charter) (State or other jurisdiction of incorporation o ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2022 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from ________________ to ________________ | --- | --- | --- | |---------------------------------------------------------------------------|---------------------- ...

| --- | --- | --- | |-------|-------|-------| | | | | | | | | | | | | Forward-Looking Statements This presentation contains forward-looking statements that involve substantial risks and uncertainties. All statements, other than statements of historical facts, contained in this presentation, including statements regarding Dyne's strategy, future operations, prospects and plans, objectives of management, the potential of the FORCE platform, and the trial design, anticipated timelines for dosing patients, and ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2022 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from ________________ to ________________ | --- | --- | --- | |---------------------------------------------------------------------------|--------------------------- ...

Building the World's Leading Muscle Disease Company COMPANY OVERVIEW | JULY 2022 Ravi, living with DMD Forward-Looking Statements This presentation contains forward-looking statements that involve substantial risks and uncertainties. All statements, other than statements of historical facts, contained in this presentation, including statements regarding Dyne's strategy, future operations, prospects and plans, objectives of management, the potential of the FORCE platform, the anticipated timelines for submit ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2022 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 | --- | --- | --- | |-------------------------------------------------------------------------|------------------------------------------------------|-----------------------------| | | | | | ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2021 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO Commission File Number: 001-39509 Dyne Therapeutics, Inc. (Exact name of Registrant as specified in its Charter) Delaware 36-4883909 (State or other jurisdictio ...