GreenLight Biosciences Launches Norroa: First RNA-Based Treatment for Varroa Mites

GreenLight Biosciences has announced the EPA registration of Norroa™, the world’s first RNA-based treatment designed to combat varroa mites—the leading threat to honey bee colonies. At a time when U.S. beekeepers face unprecedented colony losses, Norroa represents a breakthrough, providing an environmentally conscious, scientifically advanced solution to protect pollinators critical to agriculture.

A Crisis for Bees and Agriculture

Between June 2024 and March 2025, U.S. commercial beekeepers lost 1.7 million colonies, averaging a 62% loss rate, according to the Honey Bee Health Coalition. Existing miticides have lost effectiveness as varroa mites develop resistance, intensifying virus transmission within hives. USDA researchers and entomologists warn that without new tools, losses could reach 70% in 2025, threatening pollination services essential for over 100 crops worth $20 billion annually.

Operational Details: How Norroa Works

Norroa’s active ingredient, vadescana, utilizes RNA interference (RNAi), a natural biological process that precisely targets varroa mites, preventing their reproduction. Key features include:

Extended protection: up to 18 weeks of mite control.
Safety: proven safe for honey bees, brood, queens, humans, and the wider environment.
Ease of use: can be applied at any safe hive-opening temperature.
Environmental sustainability: breaks down quickly in nature without harming biodiversity.

The product is classified under IRAC Group 35, providing beekeepers with a brand-new mode of action.

Economic Impact: Supporting Beekeepers and Food Security

By maintaining low mite levels for longer periods, Norroa helps colonies survive winter and boosts overall hive health, ensuring reliable pollination for crops. Beekeepers report that the tool is not only effective but also practical, reducing reliance on outdated chemical treatments. With distribution through Mann Lake Ltd., Norroa is set to reach commercial beekeepers nationwide.

Strategic Significance: A Breakthrough in Agricultural RNA Technology

This milestone marks GreenLight’s second major EPA approval after Calantha™ in 2023, reinforcing its leadership in RNA-based agricultural innovation. With a pipeline of insecticides, fungicides, and herbicides, GreenLight aims to make farming more resilient and sustainable. Norroa’s launch represents a pivotal moment for pollinator protection and agricultural stability.