A potential first-in-class gene therapy blocking interleukin 1 (IL-1), GNSC-001 is designed to offer long-term, sustained IL-1 inhibition following a single injection into affected joint

IL-1 is a key mediator involved in pathogenesis of OA

Genascence Corporation (“Genascence”), a clinical-stage biotechnology company revolutionizing the treatment of prevalent musculoskeletal diseases with gene therapy, today announced that the U.S. Food and Drug Administration (FDA) has granted the Regenerative Medicine Advanced Therapy (RMAT) designation to GNSC-001, a potential first-in-class gene therapy blocking interleukin 1 (IL-1) for the treatment of knee osteoarthritis (OA).

GNSC-001 is a genetic medicine – a recombinant adeno-associated viral vector expressing an optimized human interleukin-1 receptor antagonist (IL-1Ra), a naturally occurring protein that blocks IL-1 signaling. IL-1 is considered one of the key mediators involved in the pathogenesis of OA, causing inflammation, joint pain, and cartilage destruction. GNSC-001 is designed to offer long-term, sustained inhibition of IL-1 following a single intra-articular injection into the affected joint.

“GNSC-001 is the first IL-1 inhibitor for OA that has been shown to generate IL-1Ra expression levels that maintain therapeutic thresholds long-term following a single administration to inhibit pathogenic IL-1. The FDA RMAT designation for GNSC-001 underscores the strength of the clinical data to date, recognizing its potential to transform the treatment paradigm for OA,” said Thomas Chalberg, Ph.D., founder and CEO of Genascence. “With the RMAT designation for GNSC-001, we look forward to working closely with the FDA as we seek to accelerate late-stage clinical development of GNSC-001 so we can bring a new treatment option to people suffering from this incapacitating, disabling disease.”

To date, GNSC-001 has been studied in two human clinical trials. The first-in-human Phase 1 study (NCT02790723) was a single-center, open-label, dose-escalation design in nine participants with knee OA. The DONATELLO Phase 1b clinical trial (NCT05835895) is a double-blind, placebo-controlled dose-ranging study designed to evaluate the safety, tolerability, and pharmacodynamics of a single intra-articular injection of GNSC-001 in patients with OA of the knee that enrolled 67 participants at 10 centers across the U.S.

The RMAT designation is a special FDA program aimed at speeding up the development and review of promising cell and gene therapies under the 21^st Century Cures Act. The FDA grants RMAT designation to drug candidates that show potential to treat, modify, reverse, or cure serious or life-threatening diseases and address unmet medical needs. The FDA’s RMAT designation offers sponsor companies all the benefits of the fast track and breakthrough therapy designation programs. In addition, RMAT designation provides accelerated development and review pathways for regenerative medicine products, including early and intensive FDA guidance, potential eligibility for accelerated approval and priority review, and the possibility of rolling review.

The U.S. Food and Drug Administration (FDA) granted GNSC-001 Fast Track designation in the fourth quarter of 2024. Earlier this year, Genascence completed a successful meeting with the FDA on the design of the Phase 2b/3 clinical trial of GNSC-001 focused on clinical efficacy and plans to initiate the Phase 2b/3 study in 2026. The DONATELLO clinical trial was supported by a $12 million award from the California Institute for Regenerative Medicine (CLIN2-14265).

About Osteoarthritis (OA) of the Knee

Osteoarthritis (OA) is a progressive joint disease that is a leading cause of disability. It is characterized by destruction of cartilage and structural changes in bone within the joint, which contribute to pain and loss of joint function. Osteoarthritis affects more than 30 million Americans and is increasing as a result of the aging population and increasing prevalence of obesity. Osteoarthritis represents a major economic burden, owing to direct medical costs and loss of productivity. Each year, millions of patients are treated for knee OA with NSAIDs, opioids, and steroid injections into the knee to manage their knee pain. There are no currently available therapies known to alter or slow down OA progression.

About Genascence Corporation

Genascence, a clinical-stage biotechnology company revolutionizing the treatment of prevalent musculoskeletal diseases with gene therapy, is developing life-changing treatments for highly prevalent conditions affecting millions of people. The company was founded in 2017 with technology licensed from three leading U.S. research institutions: Mayo Clinic, University of Florida, and NYU Langone Health. Headquartered in Palo Alto, California, Genascence’s founders and leadership team have deep experience in the design, development, and manufacturing of successful gene therapies and biological medicines. For more information, please visit www.genascence.com.

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