Scientists Poured $2 Million Into a Spray That Ends Dog Allergies—So They Could Keep Their Pet

Meet the Princeton husband-and-wife scientists who sank $2 million into an anti-allergy fix just to keep their animal companion

Last Updated:March 25, 2026

Would you drop $2,000,000 to silence your pet allergies? Married researchers Dr. Evan Zhao and Dr. Siyang Han did exactly that, building a breakthrough anti-allergy spray called Pacagen. What sparked it? Their cat, MiaoMiao.

Is There a Fix for Dog Allergies?

There's no all-purpose cure for dog allergies yet, but scientists are finding fresh ways to shut allergens down before they stir up symptoms. Pacagen's spray goes after CAN F1 and CAN F2 — the main proteins behind dog allergies — stopping them from firing the immune reaction.

The Cat Behind the $2 Million Idea

Zhao and Han's beloved British Shorthair filled their home with love — and allergies. Han turned out to be allergic, with a blocked nose, itchy eyes, and asthma flares. Unable to imagine losing MiaoMiao, Zhao, drawing on his biotech background, set out to build a remedy.

“It was so effective that I could stop taking antihistamines altogether.”

Dealing With Dog Allergies? This Scientist Pair Engineered an Answer

Zhao reached for a special family of proteins he'd studied in his PhD — ones that could be shaped to hit specific allergens — and turned them into a spray.

The outcome is their cat and dog allergen-neutralizing sprays, which are simple to use, work for anyone with cat or dog allergies, and are wholly safe for people and pets alike.

The Science Behind Pacagen's Allergen-Neutralizing Proteins

“The spray holds special proteins we've named WhiskerBlock that neutralize exactly the allergen they were built for. In the cat spray, the proteins target the allergen Fel D1. In the dog spray, the (different) proteins go after the allergens CAN F1 and CAN F2,” Zhao explains. The clever design turns allergenic tetramers into harmless monomers.

100,000 People Now Use This Spray to Cancel Dog and Cat Allergens on the Spot

Just mist the area around you. It acts at once on the allergens. “It was so effective that I could stop taking antihistamines altogether,” Han says.

So far, they've sold 100,000 units. “People are amazing at sending us updates on the product,” Evan says. “Customers are amazed at how well it works.”

This article originally appeared in the award-winningModern Dogmagazine.Subscribe today!