Prevestrus vet, a dog estrus control medication, has received European marketing authorization

Vetcare Oy has received European marketing authorisation for its product Prevestrus vet, developed for the reproductive management of female dogs.

Prevestrus vet is an oral medication designed to control estrus (heat) in female dogs. Its active ingredient, finrozole, leads to a temporary reduction in estrogen production. This shortens the follicular phase, alleviates signs of heat, and reduces the risk of pregnancy when treatment is initiated during early proestrus. A single course of treatment has not shown any long-term effects on the dog’s normal reproductive physiology.

Finrozole is a non-steroidal aromatase inhibitor that decreases estrogen formation. Estrogen is produced when androgens are converted to estrogens via the aromatase enzyme. Finrozole blocks this enzyme in the ovaries and adrenal glands, preventing the rise in blood estrogen levels and reducing symptoms caused by elevated estrogen (e.g., behavioral changes during heat, vulvar swelling, and bloody discharge). Furthermore, the drop in estrogen levels appears to advance the LH peak, accelerating follicular luteinization and shortening the time from the start of heat to ovulation.

In pivotal clinical trials involving 103 healthy female dogs in early proestrus (mainly mixed breeds), 90% of dogs treated with Prevestrus vet were in diestrus by day 10±1, compared to 0% in the control group. Only 8% of treated dogs mated (compared to 96% in the control group), and pregnancy occurred in just 2% of the treated dogs, compared to 89% in the control group.

Prevestrus is administered orally at a dose of 5 mg/kg once daily for seven (7) days, starting from the onset of proestrus or first signs of heat. The tablets should be given with food. When started at the correct time, the treatment has been shown to significantly reduce the risk of pregnancy.

The product is expected to greatly improve the lives of owners of intact female dogs during their heat cycles. It is estimated that there are approximately 40 million female dogs in Europe, of which 35–45% remain unspayed. Most female dogs experience heat twice per year. Until now, there has been no safe medication on the market to relieve the symptoms of estrus and reduce the likelihood of unwanted pregnancies.

Olli Kuussaari, CEO of Vetcare Oy, comments: "At Vetcare, our research is at the forefront of veterinary science. We focus on developing safe and effective treatments for a wide range of animal health challenges. Our commitment to innovation and excellence has resulted in significant breakthroughs in veterinary medicine. The new marketing authorisation for Prevestrus marks a major milestone for us. We are proud to provide a novel option at a time when attitudes toward the routine spaying of female dogs are shifting in many European countries due to evolving guidelines."

The preliminary launch of the prescription-only product Prevestrus vet in Finland and other European markets is expected during 2026.

Read more on the European Commission's website: Union Register of medicinal products - Public health - European Commission