FDA expands Bravecto Quantum label for two additional dog ticks

Merck Animal Health has secured an FDA label expansion for Bravecto Quantum, adding 12-month treatment and control claims in dogs for the Asian longhorned tick and the Gulf Coast tick. The company announced the update on March 18, 2026, positioning the expanded indication as a broader use case for its veterinarian-administered, extended-release fluralaner injection. (merck-animal-health.com)

The move builds on Bravecto Quantum’s original U.S. approval on July 10, 2025. At that time, the FDA described it as the first approved long-acting flea and tick treatment for dogs, with protection lasting 8 to 12 months depending on the tick species involved. The original label covered killing adult fleas and preventing flea infestations, plus control of black-legged ticks (Ixodes scapularis), American dog ticks (Dermacentor variabilis), and brown dog ticks (Rhipicephalus sanguineus) for 12 months, and lone star ticks (Amblyomma americanum) for 8 months, in dogs 6 months of age and older. FDA also stressed that the product must be prescribed by a licensed veterinarian because administration is professional-only, adverse reactions may need in-clinic management, and veterinarians must help determine the correct redosing interval based on likely tick exposure. (fda.gov, pharmashots.com)

With this latest update, the label now includes 12-month claims for Haemaphysalis longicornis and Amblyomma maculatum, in addition to previously listed 12-month coverage for black-legged, American dog, and brown dog ticks, plus 8-month coverage for lone star ticks. That distinction remains important. Merck’s own announcement says the product “continues to be indicated” for lone star ticks for 8 months, not 12, meaning the expanded approval broadens species coverage but does not eliminate the need for region-specific parasite risk assessment. The company and trade coverage have also framed the injectable as a once-yearly dosing option that could support better compliance and more continuous protection for dogs that might otherwise miss monthly preventives. (merck-animal-health.com, pharmashots.com)

The product’s safety profile remains part of the clinical conversation. FDA’s 2025 approval notice for Bravecto Quantum reiterated the class warning associated with isoxazolines, noting reported neurologic adverse reactions such as tremors, ataxia, and seizures in some dogs and cats. In the FDA freedom of information summary for Bravecto Quantum, adverse reactions included injection-site lumps or swelling, and at least one treated dog in field data experienced seizures. That does not make the product unusual for its class, but it reinforces why case selection and pet parent counseling matter. (fda.gov)

Industry context also matters here. Earlier in March 2026, BBB National Programs’ National Advertising Division reviewed Bravecto Quantum marketing after a challenge from Elanco Animal Health, a competing parasite-prevention manufacturer. NAD said Merck had a reasonable basis for the claim that Bravecto Quantum is “a safe, effective way to protect dogs year-round,” because that statement does not itself communicate a dosing frequency. But it recommended that Merck discontinue or modify other claims that more directly implied one injection provides 12 months of protection against all tick species, including phrases such as “1 quick injection. 1 full year of flea and tick protection for dogs,” “365 days of protection, all in one dose,” “year-long protection,” and “kills fleas and ticks for a full year,” unless the messaging clearly and conspicuously disclosed the 8-month lone star tick interval. Merck said it would take NAD’s recommendations for some claims under consideration while respectfully appealing part of the decision. That challenge doesn’t change the FDA-approved label, but it does underscore a practical issue for clinics: “year-round” messaging may be directionally true for some parasite risks while still being incomplete for certain tick species and geographies. (bbbprograms.org, todaysveterinarybusiness.com)

Why it matters: For veterinary professionals, the label expansion is most relevant in the context of compliance, geography, and protocol design. A single in-clinic injection can help close adherence gaps that often come with monthly preventives, particularly for pet parents who miss doses or prefer veterinarian-administered protection. At the same time, practices will still need to match recommendations to local tick ecology. Inference: the added claims for Asian longhorned and Gulf Coast ticks may increase Bravecto Quantum’s appeal in areas where those species are emerging or already established, but they don’t remove the need for individualized redosing decisions because lone star tick exposure still changes the interval. (merck-animal-health.com)

The expanded label may also sharpen competitive positioning in the canine parasiticide market. FDA’s recent approvals list shows other products are also adding claims tied to newer or spreading tick threats, including a one-month longhorned tick indication for another fluralaner product. That suggests manufacturers are responding to a changing parasite map, not just launching routine line extensions. For clinics, the practical takeaway is that parasite prevention conversations are getting more species-specific, and product selection increasingly hinges on local epidemiology as much as convenience. (fda.gov)

What to watch: Watch for FDA posting the supplemental approval details in its animal drug records, for Merck’s appeal outcome in the advertising dispute, and for whether veterinary groups and practices update parasite prevention protocols as Asian longhorned tick risk and other tick-borne disease concerns continue to shift regionally. Also watch whether Merck’s future promotional language leans more heavily on compliance and veterinarian-administered convenience rather than broad one-dose, one-year tick messaging. (merck-animal-health.com, todaysveterinarybusiness.com)