Viridian Therapeutics, Inc. announced President and Chief Executive Officer, Steve Mahoney provided key updates on the company?s anti-insulin-like growth factor 1 receptor (IGF-1R) programs in thyroid eye disease (TED) and its programs targeting FcRn. Viridian aims to build a world-class portfolio in TED with a differentiated and fast-to-market lead asset in VRDN-001, which is delivered intravenously, and a potential best-in-class asset, VRDN-003, which is designed to be self-administered subcutaneously at home as an infrequent and low-volume injection. In addition to TED, the company is also developing a novel portfolio of FcRn inhibitors with VRDN-006, an Fc fragment, and VRDN-008, which is engineered to have an extended half-life with the goal to prolong immunoglobulin G (IgG) suppression.

Thyroid Eye Disease Portfolio: VRDN-001 and VRDN-003: Intravenous VRDN-001: Viridian?s lead product candidate, VRDN-001, is a monoclonal antibody that acts as a full antagonist of IGF-1R, a clinically and commercially validated target for TED that has current US annual revenues close to $2 billion. Viridian is currently evaluating VRDN-001 in two global Phase 3 clinical trials, THRIVE and THRIVE-2, for the treatment of active and chronic TED, respectively. THRIVE and THRIVE-2 are each designed to compare a five-dose treatment arm of VRDN-001, dosed three weeks apart, to placebo.

This five-dose VRDN-001 regimen features fewer infusions and a shorter time per infusion compared to the currently marketed IGF-1R inhibitor. The company expects to report THRIVE and THRIVE-2 data in the middle of 2024 and by year end 2024, respectively. THRIVE and THRIVE-2 data will look to confirm the Phase 2 data Viridian reported throughout 2022 and 2023.

In all dose cohorts of a Phase 2 clinical trial, intravenous VRDN-001 was shown to improve the signs and symptoms of TED at six weeks in patients with active and chronic disease after two infusions. VRDN-001 was also well-tolerated. Subcutaneous VRDN-003: In December 2023, the company selected VRDN-003 as the potential best-in-class subcutaneous anti-IGF-1R program for pivotal development in TED following positive data in a Phase 1 clinical trial in healthy volunteers.

VRDN-003 has the same binding domain as its parent molecule, VRDN-001, and was engineered to have a longer half-life. VRDN-003 is designed to maintain the clinical response of VRDN-001 IV while increasing patient convenience. The Phase 1 clinical study showed VRDN-003 to have a prolonged half-life of 40-50 days, which is four to five times that of its parent molecule, VRDN-001.

Because VRDN-001 and VRDN-003 are nearly identical antibodies, the company expects VRDN-003 to have similar clinical responses at the exposure levels of VRDN-001 that led to robust clinical activity in its Phase 2 clinical study in TED. Further, pharmacokinetic modeling of VRDN-003 predicted that dosing regimens as long as every 8 weeks would achieve or exceed VRDN-001 exposure levels that were clinically meaningful. Based on these results, the company expects to initiate a global pivotal program with VRDN-003 in mid-2024, with planned trials in both active and chronic TED patients, pending alignment with regulatory authorities.

Anti-FcRn Portfolio: VRDN-006 and VRDN-008: In October 2023, consistent with Viridian?s vision to develop the next generation of best-in-class products for severe autoimmune and rare diseases, the company unveiled a portfolio of engineered FcRn inhibitors, VRDN-006 and VRDN-008. FcRn inhibitors have the potential to treat a broad array of autoimmune diseases, representing a significant commercial market opportunity. Viridian?s multi-pronged engineering approach has resulted in a portfolio of FcRn-targeting molecules that leverage the clinically and commercially validated mechanism of FcRn inhibition while potentially addressing the limitations of current agents such as incomplete IgG suppression and needed improvements in safety.

VRDN-006 is a highly-selective Fc fragment. In non-human primates, VRDN-006 showed specificity for blocking FcRn-IgG interactions while showing no decreases in albumin or increases in low-density lipoprotein (LDL) levels. VRDN-008 is a novel, first-in-class FcRn inhibitor that aims to pair IgG suppression with extended half-life technology.

VRDN-008, with its extended half-life, has the potential to more deeply and durably suppress IgG as compared to existing anti-FcRn therapies and pipeline candidates. VRDN-006 and VRDN-008 are both designed to be convenient, self-administered, subcutaneous products. Summary of Anticipated 2024 Key Program Milestones: Thyroid eye disease (TED) Portfolio: Mid-2024: THRIVE Phase 3 trial topline results in active TED for VRDN-001 IV and Initiate subcutaneous pivotal program for VRDN-003, pending regulatory alignment.

Year End 2024: THRIVE-2 Phase 3 trial topline results in chronic TED for VRDN-001 IV. Anti-FcRn Portfolio: Second half of 2024: IND submission for VRDN-006 by year end VRDN-008 NHP data.