FDA expands Bravecto Quantum label for two tick species in dogs

Merck Animal Health has won an FDA label expansion for Bravecto Quantum, adding 12-month treatment and control claims in dogs for two more tick species: Asian longhorned tick and Gulf Coast tick. The company announced the update on March 18, 2026, positioning it as an expansion of the once-yearly parasiticide’s reach at a time when veterinarians are seeing more concern about invasive and regionally shifting tick threats. (merck-animal-health-usa.com)

The move builds on Bravecto Quantum’s original FDA approval on July 10, 2025, when the agency cleared it as the first FDA-approved drug to protect dogs against fleas and ticks for 8 to 12 months. FDA said then that the product must be prescribed by a licensed veterinarian because professional expertise is needed to administer the injection, monitor for adverse reactions, advise pet parents about breeding-animal use, and determine whether the dog should follow an 8-month or 12-month treatment interval based on likely tick exposure. (fda.gov)

That dosing nuance is central to the story. According to the FDA freedom of information summary and Merck’s prescribing information, Bravecto Quantum is labeled for 12 months against fleas, black-legged tick, American dog tick, and brown dog tick, while dogs with potential exposure to lone star tick should receive it every 8 months. The new approval adds Asian longhorned tick and Gulf Coast tick to the 12-month side of the label. The product is indicated for dogs and puppies 6 months of age and older. Prescribing information also lists post-approval adverse events reported in foreign markets, including gastrointestinal signs, injection-site reactions, hypersensitivity and anaphylaxis, immune-mediated disorders, pruritus, dermatitis, and neurologic reactions such as seizures, ataxia, and tremors. (merck-animal-health-usa.com)

There’s also broader parasite-control context behind the label expansion. Merck had already secured U.S. approval in 2023 for Bravecto chews to treat Asian longhorned tick infestations for 12 weeks, suggesting the company has been working to extend fluralaner’s claims as this invasive species becomes more relevant in practice. CDC says Asian longhorned tick had been found in 20 states as of April 12, 2024, and USDA says the species has been collected across much of the eastern half of the country. CDC also notes Gulf Coast tick is found primarily in the Southeast, with focal populations in the Northeast, Midwest, and Southwest. (dvm360.com)

Industry reaction has been mixed, and not because of the new tick claims themselves. In a March 5, 2026 decision, BBB National Programs’ National Advertising Division said Merck had support for describing Bravecto Quantum as a safe, effective way to protect dogs year-round, but recommended the company discontinue or modify claims that could imply every dog gets a full year of tick protection from one dose. NAD said those messages needed to make clear that dogs exposed to lone star ticks require an 8-month dosing interval. Merck has appealed parts of that decision. That matters because the product’s convenience is a major selling point, but the real-world message to pet parents has to stay aligned with species-specific labeling. (bbbprograms.org)

Why it matters: For veterinarians, this is less about a brand headline than about another tool for tailoring parasite prevention to geography, compliance, and risk. A clinic in an area where Asian longhorned tick or Gulf Coast tick is emerging may see value in a veterinary-administered injectable that reduces missed doses and extends protection. At the same time, practices will need careful protocols for regional risk assessment, informed consent, and reminder systems, especially in lone star tick territory where “once yearly” is not the right message for every patient. FDA’s requirement that the product be veterinarian-prescribed and administered reinforces that this is a professional judgment product, not a simple convenience swap. (fda.gov)

Another practical implication is communication. Pet parents may hear “12 months” and assume that applies universally, but the label does not support that interpretation across all tick species. The recent NAD challenge shows how easily marketing shorthand can outpace label nuance. For hospitals, the safest approach is likely to frame Bravecto Quantum around species-specific tick coverage, local epidemiology, and the value of in-clinic administration for adherence, rather than around a blanket annual claim. That’s especially relevant as invasive ticks continue to expand and as vector control decisions become more localized. (bbbprograms.org)

What to watch: The next questions are whether Merck pursues additional label expansions, how the company revises marketing while its appeal proceeds, and whether uptake accelerates in regions where Asian longhorned tick and Gulf Coast tick are becoming more clinically relevant. (merck-animal-health-usa.com)