Viridian Therapeutics, Inc. Q3 FY2022 earnings call

• Positive clinical data for VRDN-001 20 mg per kg cohort, showing favorable performance vs TEPEZZA on endpoints like proptosis response rate, overall response, etc.
• Initiated the Phase 3 THRIVE trial in active TED, with sites active and screening patients. The trial will evaluate 8-infusion, 5-infusion, and placebo arms.
• VRDN-002 healthy volunteer study reported PK exceeding expectations with a long half-life.
• VRDN-003 is advancing quickly, with non-human primate data supporting good half-life, and expected to enter IND in Q2 2023.
• Ended Q3 with over $430 million in cash, providing runway into H2 2025.

VRDN-001: Positive results from the second proof-of-concept cohort for 20 mg per kg were shared, comparing favorably to TEPEZZA on key endpoints. The 3 mg per kg cohort for VRDN-001 is fully enrolled. The Phase 3 THRIVE trial in active TED was initiated. VRDN-002: Final data from the healthy volunteer study confirmed PK exceeded expectations with a half-life of up to 43 days, about four-fold better than TEPEZZA, VRDN-001, and others in development. VRDN-003: On track and advancing quickly with half-life extension technology similar to VRDN-002.

• Initiated the THRIVE Phase 3 trial in active TED with sites active and screening patients.
• Plan to present top-line data for VRDN-001 3 mg per kg cohort in early January 2023.
• VRDN-002 subcutaneous proof-of-concept trial in TED patients planned for H2 2023.
• VRDN-003 expected to enter IND in Q2 2023, with Phase 3 initiation planned for early 2024.

• Potential adverse events not yet fully known as trials progress.
• Regulatory risks in obtaining approvals for VRDN-001, VRDN-002, and VRDN-003.
• Competition in the TED market, though VRDN's products aim to be differentiated.

Q: Provide more color on discrepancy in percent of patients who achieve a CAS of zero or one between 10 and 20 mg per kg cohorts?

A: Baseline CAS in the 20 mg per kg cohort was slightly higher than in the 10 mg per kg cohort or TEPEZZA trials, explaining the appearance of difference, but both cohorts showed significant improvements in CAS.

Q: Touch upon variability in proptosis change with Hertel exophthalmometer?

A: Manual Hertel exophthalmometer can have variability, but MRI was used as a confirmatory measure in smaller studies, and MRI confirmed VRDN-001's efficacy.

Q: Color on hyperglycemia event in 20 mg per kg cohort?

A: A patient with known diabetes had glucose variability due to underlying disease, not drug-related.

Q: FDA Type C meeting on Phase 3 design?

A: Dosing arms include 8-infusion, 5-infusion, and placebo, discussed with FDA, and the shorter course may limit adverse events.

Q: Confidence in greater than every two weeks dosing for subcu?

A: 002 and 003 have every two-week dosing, 001 may be studied, but half-life extension supports an optimal profile for subcu products.

Q: Non-responders and baseline characteristics?

A: Results are consistent, non-responders usually show changes in CAS or diplopia, and no true non-responder population identified.