Norroa: a revolutionary solution for beekeepers

In a major step forward for apiculture, GreenLight Biosciences has announced the U.S. Environmental Protection Agency’s (EPA) registration of Norroa, the first-ever RNA-based treatment specifically designed to tackle Varroa mites, one of the biggest threats to honey bee populations and, by extension, global agriculture.

Norroa contains vadescana, a powerful active ingredient that uses RNA interference (RNAi), a natural process that targets the mites' reproductive system, effectively stopping their breeding cycle. The treatment’s formulation belongs to IRAC Group 35, providing a completely new mode of action for varroa control, ensuring effective mite management without harming bees. Importantly, vadescana breaks down quickly in the environment, aligning with sustainable agricultural practices.

The registration comes at a crucial time. Recent reports show alarming honey bee colony losses, with 1.7 million colonies lost between June 2024 and March 2025. Commercial beekeepers are facing average losses of 62%, partly due to the development of mite resistance to traditional chemical treatments. This, in turn, leads to higher viral loads in colonies, causing further damage to the hives.

Mark Singleton, chief commercial officer at GreenLight, said, “Norroa represents a breakthrough in honey bee protection from varroa mites, offering beekeepers an effective and easy-to-use tool that keeps mite populations down for up to 18 weeks.” He also stressed that Norroa is safe for bees, workers, and queens, with no negative effects on brood development. With few options left, beekeepers now have a much-needed alternative to chemical treatments.

The field trials speak volumes. Conducted across multiple U.S. regions, they showed Norroa effectively controls varroa mites for up to 18 weeks, improving overall colony health. By reducing mite pressure, this solution can contribute to higher colony survival rates during winter, a critical factor for maintaining healthy pollinator populations.

In the fight against varroa, Norroa™ offers a sustainable, precise solution for beekeepers, helping protect the bees that are vital to pollination and essential to the U.S. agricultural industry, valued at an estimated US$20bn annually.