Viridian Therapeutics Reports Third Quarter 2023 Financial Results and Provides Corporate Update - THRIVE and THRIVE-2 clinical trials are continuing to enroll active and chronic thyroid eye disease (TED) patients; expec

Viridian Therapeutics Reports Third Quarter 2023 Financial Results and Provides Corporate Update

- THRIVE and THRIVE-2 clinical trials are continuing to enroll active and chronic thyroid eye

disease (TED) patients; expected delivery of topline clinical results for both clinical trials on track for 2024 -

selection of lead subcutaneous TED program is on track for the end of 2023 -

- Advancing recently announced novel preclinical

portfolio of potentially best-in-class neonatal Fc receptor (FcRn) inhibitors with the broad potential to treat autoimmune diseases -

- Announced the appointment of Stephen Mahoney as President and Chief Executive Officer-

- Closed a private placement of approximately $185 million with new and existing investors to fund pipeline development and extend

operating cash runway into 2026 -

WALTHAM, Mass., November 13, 2023 Viridian Therapeutics, Inc. (NASDAQ: VRDN), a biotechnology

company focused on discovering and developing potential best-in-class medicines for serious and rare diseases, today announced financial results and provided a corporate

update for the third quarter ended September 30, 2023.

We are focused on driving execution of our potentially

best-in-class anti-IGF-1R therapies to reach meaningful clinical readouts in our

intravenous and subcutaneous TED franchise, said Steve Mahoney, President and CEO of Viridian Therapeutics. We recently reiterated our expectations for our timelines and unveiled our novel anti-FcRn portfolio for autoimmune diseases with

our first investigational new drug (IND) submission for this program planned by year end 2024. Finally, our recent closing of a private placement for approximately $185 million enables our allocation of capital to the most value-creating

results for patients and shareholders.

Thyroid eye disease (TED)

Viridian s lead product candidate,

VRDN-001, is a monoclonal antibody that acts as a full antagonist of insulin-like growth factor-1 receptor (IGF-1R), a clinically

and commercially validated target for TED that has a current US annual market opportunity of approximately $2 billion. Intravenous VRDN-001 is being evaluated in two Phase 3 clinical trials, THRIVE and THRIVE-2, for the treatment of active and chronic TED, respectively.

Subcutaneous TED Programs: VRDN-001, VRDN-002, and VRDN-003

Subcutaneous VRDN-001 is the same monoclonal antibody as the

intravenous program formulated for subcutaneous delivery. VRDN-002 constitutes a different novel monoclonal antibody targeting IGF-1R and is engineered to have an

extended half-life to allow for less frequent dosing. VRDN-003 combines the same binding domain from VRDN-001 with the same engineered extended half-life of VRDN-002. The company is conducting Phase 1 clinical trials in healthy volunteers with subcutaneous VRDN-001, VRDN-002, and VRDN-003 to evaluate each program s pharmacokinetics and safety.

Next Generation FcRn Portfolio: VRDN-006 and VRDN-008

Viridian is developing a portfolio of engineered FcRn inhibitors. FcRn inhibition has the potential to treat a broad array of autoimmune diseases,

representing a significant commercial opportunity. VRDN-006 is a highly selective Fc fragment. VRDN-008 is a novel, first-in-class FcRn inhibitor that aims to pair immunoglobulin G (IgG) suppression with extended half-life technology.

Corporate Highlights

not be hosting a conference call to discuss its third quarter financial results.

About Viridian Therapeutics

Viridian is a biopharmaceutical company focused on engineering and developing potential

best-in-class medicines for patients with serious and rare diseases. Viridian s expertise in antibody discovery and engineering enables it to develop differentiated

therapeutic candidates for previously validated drug targets in commercially established disease areas.

Viridian is advancing multiple candidates in the

clinic for the treatment of patients with thyroid eye disease (TED). The company is conducting two global Phase 3 clinical trials (THRIVE and THRIVE-2) to evaluate the safety and efficacy of VRDN-001 in patients with active and chronic TED.

Simultaneously, the company is developing its subcutaneous program strategy with the goal of providing a

potentially more conveniently administered therapy to patients with TED. In addition to its TED portfolio, Viridian is advancing a novel portfolio of neonatal Fc receptor (FcRn) inhibitors, VRDN-006 and VRDN-008, which has the potential to be developed in multiple autoimmune diseases. Viridian is also developing additional preclinical assets in autoimmune and rare diseases.

Viridian is based in Waltham, Massachusetts. For more information, please visit www.viridiantherapeutics.com. Follow Viridian on LinkedIn and

Forward-Looking Statements

release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These statements may be identified by the use of words such as, but not limited to, anticipate, believe,

continue, could, estimate, expect, intend, may, might, plan, potential, predict, project, should,

target, will, or would or other similar terms or expressions that concern our expectations, plans and intentions. Forward-looking statements include, without limitation, statements regarding our expectations,

strategies, plans and intentions. Forward-looking statements are neither historical facts nor assurances of future performance. Instead, they are based on our current beliefs, expectations, and assumptions. New risks and uncertainties may emerge

from time to time, and it is not possible to predict all risks and uncertainties. No representations or warranties (expressed or implied) are made about the accuracy of any such forward-looking statements. Such forward-looking statements are subject

to a number of material risks and uncertainties including but not limited to: the potential efficacy and safety of VRDN-001, VRDN-002, and

VRDN-003 for the treatment of Thyroid Eye Disease (TED); the potential for VRDN-006 and VRDN-008; the relationship between the

results from the positive data from the ongoing Phase 1/2 clinical trial of VRDN-001 in patients with chronic TED and the results of ongoing or future clinical trials; the timing, progress and plans for our

ongoing or future research, pre-clinical and clinical development programs; trial protocols for ongoing clinical trials; expectations regarding the timing for IND filings; expectations regarding the timing for

enrollment and data; uncertainty and potential delays related to clinical drug development; the duration and impact of regulatory delays in our clinical programs; the timing of and our ability to obtain and maintain regulatory approvals for our

therapeutic candidates, including VRDN-001, VRDN-002, and VRDN-003; manufacturing risks; our plan regarding selection of a lead

SC program candidate; competition from other therapies or products; estimates of market size; other matters that could affect the sufficiency of existing cash, cash equivalents and short-term investments to fund operations; our financial position

and its projected cash runway; our future operating results and financial performance; the clinical

utility of our therapeutic candidates and our intellectual property position; the timing of pre-clinical and clinical trial activities and reporting results from same, including those risks set forth under the caption Risk Factors in our Quarterly Report on Form

10-Q filed with the Securities and Exchange Commission (SEC) on November 13, 2023 and other subsequent disclosure documents filed with the SEC. Any forward-looking statement speaks only as of the date on

which it was made. Neither the Company, nor its affiliates, advisors, or representatives, undertake any obligation to publicly update or revise any forward-looking statement, whether as a result of new information, future events or otherwise, except

as required by law. These forward-looking statements should not be relied upon as representing the Company s views as of any date subsequent to the date hereof.

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

(amounts in thousands, except share and per share data)

Viridian Therapeutics, Inc.

Selected Financial Information

Condensed Condolidated Balance Sheets

(amounts in thousands)

Louisa Stone, 617-272-4604

Manager, Investor Relations