Miragen Therapeutics : Viridian Corporate Presentation

Viridian Therapeutics

Medicines by Design

January 2021

Cautionary Note Regarding Forward-Looking Statements

This presentation contains forward-looking statements relating to Viridian Therapeutics, Inc., including statements about our plans to obtain funding, develop and commercialize our therapeutic candidates, our planned clinical trials, the timing of and our ability to obtain and maintain regulatory approvals for our therapeutic candidates, the clinical utility of our therapeutic candidates and our intellectual property position. You can identify forward-looking statements by the use of forward-looking terminology including "believes," "expects," "may," "will," "should," "seeks," "intends," "plans," "pro forma," "estimates," or "anticipates" or the negative of these words and phrases or other variations of these words and phrases or comparable terminology. All statements other than statements of historical fact are statements that could be deemed forward-looking statements. These statements involve substantial known and unknown risks, uncertainties and other factors that may cause our actual results, levels of activity, performance or achievements to be materially different from the information expressed or implied by these forward-looking statements. These forward-looking statements should not be relied upon as predictions of future events as we cannot assure you that the events or circumstances reflected in these statements will be achieved or will occur. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements that we make due to a number of important factors, including those risks discussed in "Risk Factors" and elsewhere in our most recent Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission (SEC) on November 12, 2020 and in other filings Viridian makes with the SEC from time to time. The forward-looking statements in this presentation represent our views as of the date of this presentation. We anticipate that subsequent events and developments will cause our views to change. However, while we may elect to update these forward-looking statements at some point in the future, we have no current intention of doing so except to the extent required by applicable law. You should, therefore, not rely on these forward-looking statements as representing our views as of any date subsequent to the date of this presentation.

This presentation also contains estimates and other statistical data made by independent parties and by us relating to market size and other data about our industry. This data involves a number of assumptions and limitations, and you are cautioned not to give undue weight to such estimates. In addition, projections, assumptions and estimates of our future performance and the future performance of the markets in which we operate are necessarily subject to a high degree of uncertainty and risk.

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Expanding the Definition of Innovation in Drug Discovery

Conventional approach

Drug discovery often prioritizes differentiation more than is necessary

• Focus on the "new" (targets, modalities, platform technologies) leaves many therapeutic spaces under competitive
• Still limited treatment options for patients, many left with only one option

The Viridian approach

Compelling opportunities in under competitive markets

• Suboptimal products
• Limited patient access
• High prices

Product-focused hypotheses leveraging lower risk approaches

• Validated science
• Trusted modalities
• Proven technologies
• Valuable markets

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Viridian Therapeutics Pipeline

2021

2022

1Q

2Q

3Q

4Q

1Q

2Q

3Q

4Q

VRDN-001 (IV)

New IND 3Q21

Ph2 pilot data 1Q22

Ph2 data MY22

Thyroid Eye

VRDN-002 (SC)

IND YE21

Ph1 data 1H22

Ph2 data 1H23

Disease (TED)

VRDN-003 (SC)

IND 2022

Undisclosed

VRDN-004

IND 2022

TBD

VRDN-005

IND 2022

Note: VRDN-001, previously AVE-1642, was licensed from ImmunoGen/Sanofi *Projected timelines pending regulatory feedback

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