Executive Summary / Key Takeaways

• Differentiated Pipeline for a Growing Market: Viridian Therapeutics is strategically positioned to capture significant share in the multi-billion dollar Thyroid Eye Disease (TED) market with its dual-pronged approach: veligrotug (IV) offering a shorter, more convenient infusion regimen, and VRDN-003 (subcutaneous) aiming for best-in-class at-home self-administration.
• Strong Clinical and Regulatory Momentum: Veligrotug has achieved Breakthrough Therapy Designation from the FDA, with positive Phase 3 data (THRIVE and THRIVE-2) supporting a BLA submission in H2 2025 and an EMA MAA in H1 2026. VRDN-003 is also advancing rapidly, with pivotal trials commencing mid-2025 and a BLA targeted by end of 2026.
• Expanding Beyond TED with FcRn Inhibitors: The company is building a promising FcRn inhibitor portfolio (VRDN-006, VRDN-008) for a broad array of autoimmune diseases, leveraging protein engineering for improved half-life and IgG suppression, with initial data readouts expected in 2025.
• Robust Financial Position and Strategic Partnerships: With $563.4 million in cash and equivalents as of Q2 2025, Viridian has a runway into H2 2027, bolstered by a recent $70 million upfront payment from its Kissei collaboration for the Japan market, providing ample capital to execute on its ambitious clinical roadmap.
• Competitive Edge through Innovation and Convenience: Viridian's technological differentiators, including veligrotug's full IGF-1R antagonism and VRDN-003's extended half-life for at-home use, are designed to address unmet needs in the "new start market" of TED, offering superior patient convenience and potentially enhanced efficacy compared to existing therapies.

Viridian's Vision: Redefining Treatment in Rare Autoimmune Diseases

Viridian Therapeutics, Inc. (NASDAQ:VRDN) is a biopharmaceutical company dedicated to discovering, developing, and commercializing best-in-class medicines for serious and rare diseases. The company's core strategy revolves around identifying market opportunities where existing therapies leave room for improvement in efficacy, safety, or dosing convenience. This "fast-follower" approach aims to engineer superior therapeutics and rapidly advance them through development to patients.

The company's journey began as miRagen Therapeutics, Inc., transforming into Viridian Therapeutics in January 2021 following a strategic merger. This pivotal shift marked a clear focus on its current mission, quickly followed by key licensing agreements, including a collaboration with Zenas BioPharma for IGF-1R antibodies in greater China and an exclusive license with ImmunoGen (IMGN) for intellectual property rights. This foundational work laid the groundwork for Viridian's current pipeline, particularly its lead programs in Thyroid Eye Disease (TED).

The TED market is a significant opportunity, estimated to affect 190,000 moderate to severe patients in the U.S. alone, with the global market projected to grow from $2 billion (U.S. only in 2022) to over $4 billion. Management characterizes TED as a "new start market" driven by disease flares, meaning patients continuously seek new treatment options without displacing chronic therapies. This dynamic creates a fertile ground for differentiated new entrants. Beyond TED, Viridian is strategically expanding into the broader autoimmune space with its FcRn inhibitor portfolio, recognizing the substantial commercial potential in autoantibody-mediated diseases, where the first approved FcRn inhibitor already generates over $1 billion in annual sales.

Technological Edge: Engineering Best-in-Class Therapies

Viridian's investment thesis is deeply rooted in its commitment to technological differentiation, aiming to deliver superior patient outcomes and convenience. The company's pipeline is built on advanced antibody engineering, particularly for its IGF-1R and FcRn programs.

Veligrotug (VRDN-001): A Differentiated IV Approach for TED

Veligrotug is a humanized monoclonal antibody targeting the insulin-like growth factor-1 receptor (IGF-1R), a clinically and commercially validated target for TED. Viridian positions veligrotug as a full antagonist of IGF-1R, a key differentiator from the current market leader, teprotumumab, which is described as an incomplete antagonist. This mechanistic difference underpins the potential for enhanced efficacy.

Clinical data from Phase I/II trials demonstrated robust and rapid improvements in TED signs and symptoms. In active TED patients, veligrotug achieved a 75% overall response rate (defined as at least a 2mm proptosis reduction and a 2-point CAS improvement), significantly higher than teprotumumab's 44% in its Phase 2/3 trials. The proptosis responder rate was 75% (vs. 55-56% for teprotumumab), and 58% of patients achieved a Clinical Activity Score (CAS) of 0 or 1, which is 2.5 to 3 times higher than teprotumumab. Crucially, 75% of patients with baseline diplopia experienced complete resolution, more than double the rate observed with teprotumumab.

Beyond efficacy, veligrotug is engineered for patient convenience. Its proposed 5-dose, 12-week regimen is 43% shorter than teprotumumab's 8-dose, 21-week course, and infusions are designed to take 30 minutes compared to 60-90 minutes for the competitor. Long-term durability data from the THRIVE trial further supports this, showing that 70% of proptosis responders at week 15 maintained their response at week 52, suggesting a shorter treatment course can provide durable efficacy.

VRDN-003: The Future of Subcutaneous TED Treatment

VRDN-003 represents Viridian's next-generation IGF-1R monoclonal antibody, sharing the same binding domains as veligrotug but incorporating half-life extension technology. This engineering aims to translate veligrotug's efficacy into a highly convenient, self-administered subcutaneous format.

The key technological advantage of VRDN-003 is its prolonged half-life of 40 to 50 days in healthy volunteers, which is four to five times longer than that of veligrotug and teprotumumab. This extended half-life enables less frequent, low-volume subcutaneous injections, with the potential for at-home self-administration via an auto-injector. This shift in administration could be a "game changer" for TED patients, significantly reducing the burden of frequent clinic visits. The company's pharmacokinetic modeling predicts that VRDN-003, administered every four or eight weeks, could achieve or exceed the robust clinical activity seen with veligrotug in its Phase 2 trials.

FcRn Inhibitor Portfolio: Expanding Autoimmune Horizons

Viridian is also leveraging its protein engineering expertise to develop a portfolio of anti-neonatal Fc receptor (FcRn) inhibitors, VRDN-006 and VRDN-008, for a broad range of autoantibody-mediated autoimmune diseases. This strategy aims to build upon the clinically and commercially validated mechanism of FcRn inhibition while addressing limitations of current agents.

• VRDN-006 is a highly selective Fc fragment designed for convenient subcutaneous and self-administered options. In non-human primate (NHP) studies, it demonstrated comparable potency and IgG reductions to efgartigimod (the current standard of care in FcRn inhibition) while notably sparing albumin or LDL levels, which are potential side effects of some full-length anti-FcRn monoclonal antibodies.
• VRDN-008 is a half-life extended bispecific FcRn inhibitor. In NHP studies, VRDN-008 showed three times the half-life of efgartigimod, leading to 20% deeper peak IgG reductions and a more sustained effect, with IgG levels returning to baseline 35 days after dosing, more than twice as long as efgartigimod (14 days). This deeper and more durable IgG suppression could offer a best-in-class option for patients requiring prolonged disease control.

These technological advancements are crucial for Viridian's competitive moat, enabling it to offer differentiated products that could command premium pricing, achieve higher market penetration, and ultimately drive superior financial performance and long-term growth.

Competitive Arena: Outmaneuvering Established Giants

The biotechnology landscape, particularly in rare diseases, is intensely competitive, with Viridian facing both established pharmaceutical giants and nimble biotech innovators. In the Thyroid Eye Disease (TED) market, the primary competitor is Amgen Inc. (AMGN), which markets Tepezza (teprotumumab). Tepezza generated approximately $1.8 billion in U.S. sales in 2023, demonstrating the significant market opportunity.

Viridian's strategy is to be a "fast-follower" with differentiated, best-in-class products. For veligrotug (IV), the competitive edge lies in its shorter 5-dose regimen and 30-minute infusion time, offering a clear convenience advantage over Tepezza's 8-dose, 60-90 minute regimen. Furthermore, veligrotug's full IGF-1R antagonism versus teprotumumab's incomplete antagonism presents a potential efficacy differentiator. While direct, head-to-head financial comparisons are challenging given Viridian's clinical stage, the qualitative benefits of reduced treatment burden and potentially superior clinical outcomes are critical for market adoption. Amgen, with its vast resources and established commercial infrastructure, benefits from first-mover advantage and broad market access. However, management notes that "integration isn't easy" for large acquisitions like Amgen's of Horizon, potentially creating opportunities for agile entrants like Viridian.

For the subcutaneous (subcu) TED market, VRDN-003 aims to be a first-in-class self-administered option. Management highlights that "a later entrant subcu therapy can convert meaningful portions of an existing IV market" and "grow the overall market size." This is particularly relevant in the "new start market" of TED, where patients are continuously seeking treatment for flares. VRDN-003's 40-50 day half-life (4-5x that of veligrotug/Tepezza) is a significant technological advantage, enabling less frequent dosing and at-home administration, a convenience factor that could drive rapid market conversion and expansion.

In the FcRn inhibitor space, Viridian competes with companies like Argenx (ARGX) (efgartigimod/Vyvgart), UCB S.A. (UCB), Johnson & Johnson (JNJ), and Immunovant, Inc. (IMVT). The FcRn market is substantial, with efgartigimod already annualizing over $1 billion in sales for myasthenia gravis, a market projected to exceed $4 billion annually by 2028. Viridian's VRDN-006, as an Fc fragment, aims to replicate efgartigimod's efficacy while potentially improving tolerability by sparing albumin/LDL. VRDN-008, with its three times longer half-life and 20% deeper peak IgG reductions compared to efgartigimod in NHP studies, is designed to offer a best-in-class profile for durable IgG suppression. This focus on enhanced convenience and deeper, more sustained therapeutic effect provides a strong competitive position against existing and emerging FcRn therapies.

While larger competitors like Amgen, Novartis (NVS), Roche (RHHBY), and Regeneron (REGN) possess significantly greater financial, R&D, and commercialization resources, Viridian's focused innovation and patient-centric product design offer a distinct competitive advantage in specific niches. The company's reliance on third-party manufacturers, such as WuXi Biologics (WXXWY), introduces geopolitical risks, including potential impacts from the proposed BIOSECURE Act, which could necessitate costly and time-consuming transitions to alternative suppliers. However, strategic collaborations, such as the recent agreement with Kissei Pharmaceutical for the Japan market, demonstrate Viridian's ability to leverage partnerships to expand its global footprint and de-risk commercialization efforts.

Financial Health and Operational Momentum

Viridian Therapeutics is in a significant investment phase, as reflected in its recent financial performance. For the six months ended June 30, 2025, the company reported minimal collaboration revenue of $147 thousand, consistent with its pre-commercial stage. This revenue primarily stems from its agreement with Zenas BioPharma.

Operating expenses have seen substantial increases, driven by aggressive clinical development. Research and development (R&D) expenses for the six months ended June 30, 2025, surged to $163.46 million, a significant increase from $97.14 million in the prior year period. This rise was primarily attributable to a $41.16 million increase in clinical trial costs and a $6.4 million increase in chemistry, manufacturing, and controls (CMC) costs for the ongoing global Phase 3 trials of veligrotug and VRDN-003. The FcRn inhibitor portfolio also contributed to this increase, with a $10.4 million rise in CMC costs for IND-enabling activities, a $4.5 million increase in clinical study costs for VRDN-006, and $5.5 million in milestone, license, and option fees paid to Paragon for VRDN-008 and VRDN-006.

General and administrative (G&A) expenses also increased to $37.32 million for the six months ended June 30, 2025, up from $31.09 million in the prior year. This was mainly due to a $4.4 million increase in personnel-related costs to support organizational growth, a $3.3 million increase in market research and related costs for veligrotug's potential commercialization, and a $2.5 million increase in legal, accounting, and other professional service fees.

The company reported a net loss of $187.65 million for the first six months of 2025, compared to $113.54 million in the same period of 2024. Operating cash flow for the six months ended June 30, 2025, was a use of $168.03 million, reflecting the intensive R&D investment. Despite these losses, Viridian maintains a robust liquidity position, with $563.4 million in cash, cash equivalents, and short-term investments as of June 30, 2025. This capital is projected to fund operations into the second half of 2027, providing a substantial runway for its clinical programs. The company's financial strength was further enhanced by a $70 million upfront payment from the Kissei collaboration in July 2025, with potential for up to $315 million in additional milestone payments and tiered royalties. The interest-only period for its Hercules Loan and Security Agreement was also extended to April 1, 2026, following positive Phase 3 data, further easing near-term debt obligations.

Outlook and Catalysts: The Road Ahead

Viridian Therapeutics is poised for a series of significant catalysts that could fundamentally reshape its market position and valuation. The company's outlook is characterized by aggressive clinical execution and strategic commercial preparations.

For the veligrotug intravenous (IV) program, a Biologics License Application (BLA) submission to the U.S. FDA is anticipated in the second half of 2025, followed by a Marketing Authorization Application (MAA) to the European Medicines Agency (EMA) in the first half of 2026. This accelerated timeline is supported by the recent Breakthrough Therapy Designation granted by the FDA in May 2025, underscoring the potential for veligrotug to offer substantial improvement over existing TED therapies. The positive topline data from the Phase 3 THRIVE study (active TED) in September 2024 and THRIVE-2 study (chronic TED) in December 2024, along with positive long-term durability data from THRIVE in May 2025, provide a strong clinical foundation for these regulatory filings. The STRIVE safety study, which completed enrollment with 231 patients, is expected to provide the necessary safety database without impacting the BLA timeline.

The VRDN-003 subcutaneous (subcu) program is also advancing rapidly. Following a positive Type C meeting with the FDA, pivotal clinical trials for VRDN-003 are on track to initiate in mid-2025. Topline data from the Phase 3 REVEAL-1 (active TED) and REVEAL-2 (chronic TED) studies are anticipated in the first half of 2026, with a BLA submission for VRDN-003 for TED targeted by the end of 2026. A critical operational detail is the plan to initiate an auto-injector study for VRDN-003 in 2025, which is essential for enabling at-home self-administration upon approval.

In its FcRn inhibitor portfolio, Viridian expects proof-of-concept IgG reduction data for VRDN-6.00 in healthy volunteers in the third quarter of 2025. This will be a key indicator of its potential as a convenient subcutaneous option. Furthermore, an Investigational New Drug (IND) Application for VRDN-8.00, the half-life extended bispecific FcRn inhibitor, is anticipated by the end of 2025, building on promising non-human primate data shared in the second half of 2024.

These upcoming milestones, coupled with the strategic collaboration with Kissei Pharmaceutical for the Japan market, highlight Viridian's aggressive execution and clear roadmap towards commercialization across multiple programs and geographies.

Risks on the Horizon

Despite the promising outlook, Viridian Therapeutics faces several inherent risks common to the biotechnology sector. A significant concern is the reliance on third-party manufacturing, particularly with Chinese contract development and manufacturing organizations (CDMOs) like WuXi Biologics. Increased governmental scrutiny in the U.S. on Chinese life sciences companies, exemplified by the proposed BIOSECURE Act, could force Viridian to seek alternative manufacturers. Such a transition could lead to substantial delays, increased costs, and potential supply disruptions, materially impacting clinical trials and commercialization efforts.

The development of combination products like VRDN-3.00, VRDN-6.00, and VRDN-8.00 (integrating a drug with a device) introduces additional complexities in manufacturing and regulatory review, potentially causing delays. Furthermore, while preliminary clinical data has been positive, the interpretation and final verification of clinical trial results remain a risk. Differences between preliminary and final data, or varying interpretations by regulatory authorities, could lead to additional study requirements, increased costs, or delays in approval.

Competitive pressures in both the TED and FcRn markets are substantial. While Viridian aims for differentiation, established players like Amgen (Tepezza) have significant market presence, resources, and commercial infrastructure. Other companies are also developing competing therapies, and their success could impact Viridian's market share and pricing power. The regulatory approval process is inherently lengthy and unpredictable, with the FDA and other agencies having broad discretion. Potential changes in FDA operations or workforce under the current presidential administration could also lead to delays in review and approval timelines.

Finally, broader macroeconomic conditions, including inflation, rising interest rates, and geopolitical instability, could increase operating costs, affect capital availability, and disrupt global supply chains, impacting Viridian's financial condition and operational execution. The increasing adoption of AI technologies also introduces new risks related to intellectual property, data security, and evolving regulatory frameworks, which could lead to unforeseen compliance costs or operational challenges.

Conclusion

Viridian Therapeutics is at a pivotal juncture, poised to redefine the treatment landscape for Thyroid Eye Disease and expand into other significant autoimmune indications. The company's core investment thesis is built on its ability to engineer and rapidly advance differentiated, best-in-class biologics that offer superior efficacy, safety, and, critically, enhanced patient convenience. The dual strategy in TED, with veligrotug (IV) providing a shorter, more efficient infusion regimen and VRDN-003 (subcu) targeting at-home self-administration, directly addresses key unmet needs in a growing "new start market."

With veligrotug's Breakthrough Therapy Designation and positive Phase 3 data paving the way for BLA and MAA submissions in 2025 and 2026, and VRDN-003's advanced half-life technology entering pivotal trials, Viridian demonstrates strong operational momentum. The burgeoning FcRn inhibitor pipeline further underscores the company's long-term growth potential. Supported by a robust cash position and strategic partnerships, Viridian is well-capitalized to execute its ambitious roadmap. While competitive pressures and regulatory complexities remain, the company's technological leadership and patient-centric approach position it strongly to capture significant market share and deliver substantial value to investors as it brings these innovative therapies to patients worldwide.