Polyrizon Ltd. (PLRZ) shares exploded 139.77% to $17 in after-hours trading on Wednesday, a dramatic move for the Israel-based biotechnology company that closed regular trading at $7.09, down 3.27%.
So what sparked the rally? Two things, actually, and both matter for a small biotech trying to make its mark in the naloxone space.
Better Adhesion, Better Results
First, Polyrizon announced preclinical test data showing its proprietary naloxone hydrogel adheres to nasal tissue longer than an approved intranasal naloxone spray already on the market. That's important because the longer a medication stays where it's supposed to be, the better it can do its job.
The company used an ex-vivo rabbit nasal mucosa model for the testing. Researchers applied each formulation to mucosal tissue and washed it with Simulated Nasal Electrolyte Solution over a 30-minute period to see what stuck around.
Compared with the commercial product, Polyrizon's Trap and Target hydrogel showed higher fluorescence marker values, with differences reaching statistical significance (p < 0.0001, two-way ANOVA). In plain English, the results weren't just better—they were significantly better in a way that matters scientifically.
What Management Is Saying
Tomer Izraeli, CEO of Polyrizon, said, "The ability to significantly outperform an existing marketed product in mucoadhesion is an important milestone as we continue advancing our Naloxone program."
Fair enough. Beating an existing commercial product in preclinical tests is exactly the kind of thing that gets investors excited about a small biotech's prospects.
Manufacturing Gets Real
The second announcement matters too, even if it's less flashy. Polyrizon reached a major manufacturing upscaling milestone for its nasal-spray platform, moving from small-batch laboratory production to larger-scale controlled manufacturing to validate key parameters of its PL-14, a proprietary bio-adhesive formulation.
That's the kind of behind-the-scenes progress that doesn't make headlines but tells you whether a company can actually produce what it's developing. Going from lab scale to manufacturing scale is where a lot of biotechs stumble.
The Bigger Picture
Context matters here. PLRZ is down 99.74% year-to-date, though it has rebounded 45.88% over the past six months. The company has a market capitalization of $7.39 million, which means it's a small player making big claims.
This after-hours surge could change that calculus, but it's worth remembering that preclinical data and manufacturing milestones are early-stage wins. There's still a long road ahead before any of this translates into revenue or wider adoption.