A Calgary-based company, Solvet, has received emergency use authorization from the U.S. Food and Drug Administration (FDA) to market its equine ivermectin product in the United States. This approval allows Solvet to combat screwworm, a parasitic threat. The liquid ivermectin, unlike traditional paste forms, is an aqueous-based solution that is more concentrated and easier to administer, according to Lionel Gibbs, the CEO of Solvet.
Founded in 2009 by two former University of Calgary professors, Solvet has evolved into one of Canada’s leading veterinary pharmaceutical companies. Ivermectin, a well-known anti-parasitic drug, is commonly used to combat various parasites, including screwworm, a type of fly indigenous to certain regions of North America. Female screwworm flies lay eggs on open wounds of animals such as horses, cattle, and occasionally humans. The larvae that hatch penetrate the host’s tissue, causing severe pain, secondary infections, and potential fatality.
Screwworm infestations have historically resulted in significant economic losses for ranchers in the United States and Mexico until a successful eradication effort using the sterile insect technique. This approach capitalizes on the fact that female screwworm flies only mate once and store sperm for egg fertilization. By releasing sterilized male flies in vast numbers, subsequent fly generations are eliminated. The technique was highly successful, with screwworms being eradicated north of the Panama Canal by 2006.
However, in recent years, screwworm has reappeared in Central America, Mexico, and southern parts of the United States, causing concern among authorities. In response to the screwworm larvae discovery on a calf in Texas in June 2026, the Canadian Food Inspection Agency (CFIA) suspended animal imports from the state.
While efforts to produce sterile males have resumed in the U.S., it will take time to reach levels required for fly eradication. In the interim, the FDA sought assistance from pharmaceutical companies to address the screwworm risk. Following a thorough evaluation of Solvet’s facilities, manufacturing processes, and ivermectin liquid data, emergency authorization was granted for the specific use against screwworm in the U.S.
The authorization permits the short-term prevention of screwworm in horses using the liquid ivermectin within 24 hours of birth or during initial wound care. Veterinarian John Gilleard, specializing in parasitology, supports the authorization as a means to safeguard animals in regions like Texas where screwworm poses a considerable threat. The focus is on protecting animals at risk rather than controlling outbreaks.
Considering the low risk of screwworm in Canada due to the climate, the CFIA continues to monitor the situation closely in collaboration with U.S. animal health authorities. Solvet sees this authorization as an opportunity to enhance animal welfare and expand its presence in the U.S., potentially benefiting Alberta’s economy through increased research funding and market opportunities.