Pacira BioSciences will present extended follow-up data from its Phase 1 clinical trial of PCRX-201 (enekinragene inzadenovec) at the American College of Rheumatology Convergence 2025 meeting, demonstrating sustained clinical benefits in knee osteoarthritis patients through three years of follow-up. The poster presentation, scheduled for October 28, will showcase data from the novel gene therapy that targets the underlying chronic inflammatory processes contributing to osteoarthritis progression.
Phase 1 Trial Results Show Durable Response
The Phase 1 study enrolled 72 patients and previously demonstrated that PCRX-201 provided sustained improvements in knee pain, stiffness, and function through two years following local administration. The therapy maintained a well-tolerated safety profile throughout the extended follow-up period. These results represent a significant milestone for gene therapy applications in osteoarthritis, a degenerative joint disease affecting nearly 15 million individuals in the United States.
Dr. Stanley Cohen, Co-Medical Director of Metroplex Clinical Research Center in Dallas, will present the findings during the poster session titled "PCRX-201 High-Capacity Adenovirus Serotype 5 Gene Therapy Demonstrates Sustained Clinical Efficacy and Safety in Patients with Knee Osteoarthritis."
Innovative High-Capacity Adenovirus Platform
PCRX-201 is built on Pacira's proprietary high-capacity adenovirus (HCAd) vector platform, acquired through the company's February 2025 purchase of GQ Bio Therapeutics GmbH. This platform addresses several key limitations that have historically prevented gene therapy utilization in common diseases like osteoarthritis.
The HCAd vector demonstrates superior efficiency in delivering genes into cells compared to adenovirus-associated virus (AAV) vectors commonly used in other gene therapies. This enhanced efficiency allows therapeutic effects to be achieved with significantly smaller doses. Additionally, the vector can accommodate up to 30,000 base pairs of DNA, enabling the delivery of multiple or larger genes compared to AAV-based systems.
The platform's design allows for local administration and potential redosing at therapeutically appropriate intervals. The combination of lower required doses and efficient cellular delivery enables the production of thousands of doses in a single manufacturing batch, creating a commercially viable cost structure for the therapy.
Regulatory Recognition and Development Pipeline
PCRX-201 has achieved significant regulatory milestones, receiving both Regenerative Medicine Advanced Therapy (RMAT) designation from the U.S. Food and Drug Administration and Advanced Therapy Medicinal Products (ATMP) designation from the European Medicines Agency. These designations mark PCRX-201 as the first gene therapy to earn such regulatory recognition specifically for knee osteoarthritis treatment.
The company is currently conducting the Phase 2 ASCEND study to further evaluate PCRX-201's therapeutic potential in knee osteoarthritis patients. Beyond this lead candidate, Pacira has identified numerous well-validated cytokines that could serve as the foundation for additional locally administered genetic therapies using the HCAd platform.
Addressing Unmet Medical Need
Osteoarthritis represents a significant unmet medical need, with the knee being one of the most commonly affected joints. The condition involves progressive "wear and tear" processes driven by chronic inflammation, leading to pain, stiffness, and functional impairment that significantly impacts patients' quality of life.
PCRX-201's approach of targeting the fundamental inflammatory processes underlying osteoarthritis progression represents a potential paradigm shift from current symptomatic treatments. The sustained clinical benefits observed in the Phase 1 trial suggest that gene therapy could provide long-lasting therapeutic effects with a single local administration, potentially transforming the treatment landscape for this prevalent condition.
