Virpax Pharmaceuticals has announced positive results from a human study of its Molecular Envelope Technology (MET), marking a significant advancement for the company's drug delivery platform. The Phase I SUNLIGHT trial, conducted by Nanomerics, demonstrated no moderate to severe adverse events after 28 days of administration.
The trial, which ran from December 2024 to January 2025, involved twice-daily administration of MET eye drops and OC134 eye drops to healthy volunteers. This safety data represents a crucial milestone for Virpax's development pipeline, which utilizes MET in multiple product candidates.
Key Applications of Molecular Envelope Technology
Virpax currently employs MET in two of its lead product candidates: Envelta (NES100) and NobrXiol (VRP324).
Envelta is an enkephalin-based analgesic that leverages MET to facilitate drug delivery across the blood-brain barrier. The nanotechnology approach is designed to protect and transport the active compound to the brain, where it binds to delta opioid receptors to suppress pain. Notably, Envelta has shown analgesic effects in animal models without developing opioid tolerance or reward-seeking behavior—a critical advantage in addressing the ongoing opioid crisis.
The development of Envelta continues under a cooperative research and development agreement with the National Center for Advancing Translational Sciences (NCATS), part of the National Institutes of Health. In November 2024, Virpax announced an extension of this agreement to further advance NES100 toward an Investigational New Drug (IND) application for acute and chronic non-cancer pain.
NobrXiol represents another application of MET, focusing on the delivery of cannabidiol for epilepsy management in both pediatric and adult patients. The technology enables cannabidiol nanoparticles to cross the blood-brain barrier via intranasal administration through the olfactory nerve. NobrXiol has already received pre-IND guidance from the U.S. Food and Drug Administration.
Expanding Applications for MET
Beyond its current applications, Virpax is exploring the use of MET or similar technologies to develop an intranasal mRNA COVID vaccine, as announced in early March 2025. This potential expansion demonstrates the versatility of the company's delivery platform and its applicability across multiple therapeutic areas.
"The successful completion of this human study with no moderate to severe adverse events represents a significant milestone for our MET platform," said a Virpax representative. "These results support our continued development of non-addictive pain management solutions and CNS-targeted therapies."
Broader Pipeline Progress
In parallel with the MET developments, Virpax has made progress with other pipeline candidates. The company recently completed a swine model dose-range finding study for Probudur, a long-acting liposomal bupivacaine formulation designed for injection at wound sites to provide immediate and extended pain relief.
Additionally, Virpax has strengthened its financial position through recent public offerings. In January 2025, the company closed a $6 million follow-on offering of common stock and pre-funded warrants, with Spartan Capital Securities serving as the sole placement agent. This followed a $5 million public offering that closed in November 2024.
Market Position and Strategy
Virpax Pharmaceuticals, based in Berwyn, Pennsylvania, continues to focus on developing non-addictive products for pain management, post-traumatic stress disorder, central nervous system disorders, and anti-viral barrier indications. The company's emphasis on novel drug delivery systems positions it uniquely in the pharmaceutical landscape.
The positive human safety data for MET strengthens Virpax's technological foundation as it advances multiple candidates through preclinical and early clinical development. With ongoing collaborations with government research institutions like the U.S. Army Institute of Surgical Research and NCATS, Virpax is leveraging partnerships to accelerate its development programs.
As the company progresses toward IND applications for its lead candidates, the successful demonstration of MET's safety profile in humans represents a critical de-risking event that may facilitate regulatory advancement across its pipeline.
