PolarityBio Completes Pivotal Phase 3 Trial of SkinTE for Diabetic Foot Ulcers

Last week, PolarityBio announced the successful completion of its pivotal phase 3 clinical trial evaluating SkinTE, an autologous heterogeneous skin construct, for the treatment of Wagner Grade 1 diabetic foot ulcers (DFUs).¹ The COVER DFUS II randomized trial reached Last Patient Last Visit on November 12, 2025, marking a major milestone for the company’s biologic program and advancing SkinTE toward potential Biologics License Application (BLA) submission. Final trial data are expected in the first quarter of 2026.

Ashlee Fishleigh, Chief Clinical Officer of PolarityBio, said in a statement, “I want to personally thank our clinical research investigators and the dedicated research coordinators who have supported this program. Your expertise, commitment to high-quality research, and steady focus on patient safety and care have been critical in moving this work forward...To all parties involved, thank you. Your collective efforts are making a real impact and bringing us closer to delivering new and potentially life-changing therapies to the patients who need them most.”¹

SkinTE represents a first-in-class autologous multicellular therapy designed to support regenerative healing in chronic wounds. DFUs remain a substantial clinical challenge, contributing to high morbidity, health care costs, and lower-extremity amputations. Notably, no biologic has received BLA approval for a chronic wound indication since 1997, underscoring the persistent therapeutic gap and the importance of rigorous clinical development in this area.

Trial Design and Enrollment

COVER DFUS II was a multicenter, randomized, controlled, registrational trial enrolling 120 patients across diverse US clinical sites. Recruitment was completed in just 14 months—an accelerated pace compared to past DFU trials—with an average enrollment of 8.6 patients per month. Participants were randomized 1:1 to receive either SkinTE plus standard of care (SOC) or SOC alone and were followed for 24 weeks.

Eligibility criteria reflected a chronic, treatment-refractory DFU population. All participants had ulcers present for at least 4 weeks and were required to complete a 2-week run-in with optimized SOC. Only ulcers that demonstrated less than 30% size change during this run-in qualified for randomization.

The study’s primary endpoint was the incidence of complete wound closure by week 12. Secondary endpoints included time to healing, percentage area reduction, hospitalization, and clinic utilization related to the index ulcer, days of CAM boot use, and the proportion of treatment-emergent adverse events.

Investigator and Patient Perspectives

Robert Kirsner, MD, PhD, Chairman and Harvey Blank Professor of the Dr. Phillip Frost Department of Dermatology and Cutaneous Surgery at the University of Miami Miller School of Medicine, and Chair of the COVER DFUS II study, noted the importance of this clinical research. “Ideas are common, but taking those ideas and studying them to prove their validity is much less common. Patient care depends on this, and the COVER II trial is the type of work needed to help reduce the burden and impact of diabetic foot ulcers on patients and society,” he said.¹

Principal investigator Jason Hanft, DPM, FACFAS, shared similar thoughts on this milestone. “I extend sincere congratulations to PolarityBio for reaching the last patient visit in their Phase III trial for SkinTE as a diabetic foot ulcer treatment,” he added. “This marks an impressive milestone and a significant step forward in advancing care for patients with chronic wounds. I wish the company continued success as they move toward the next phase of this important work.”¹ A patient treated at his site expressed gratitude for the treatment, stating that their “extra-large wound” healed with no pain, “saving [their] foot.”¹

Regulatory Momentum

Earlier in 2025, the US Food and Drug Administration granted Breakthrough Therapy designation to SkinTE for the treatment of Wagner Grade 1 DFUs.² This status is reserved for therapies demonstrating the potential for substantial improvement over existing options for serious conditions. The designation not only acknowledges the clinical promise of SkinTE but also provides opportunities for enhanced regulatory interaction and potential acceleration of the review process.

With COVER DFUS II now complete, PolarityBio plans to analyze final data and prepare for a potential BLA submission pending trial outcomes. If successful, SkinTE could offer dermatologists and wound-care clinicians a novel autologous, regenerative option for chronic DFUs.

References

1. PolarityBio Completes Phase III Pivotal Study of SkinTE for Diabetic Foot Ulcers. News release. Globe Newswire. Published December 2, 2025. Accessed December 8, 2025. https://www.globenewswire.com/news-release/2025/12/02/3197960/0/en/PolarityBio-Completes-Phase-III-Pivotal-Study-of-SkinTE-for-Diabetic-Foot-Ulcers.html

2. PolarityBio Receives U.S. FDA Breakthrough Therapy Designation for Treatment of Wagner Grade I Diabetic Foot Ulcers (DFU). Published February 20, 2025. Accessed December 8, 2025. https://www.globenewswire.com/news-release/2025/02/20/3029651/0/en/PolarityBio-Receives-U-S-FDA-Breakthrough-Therapy-Designation-for-Treatment-of-Wagner-Grade-I-Diabetic-Foot-Ulcers-DFU.html