FDA Approves BRAVECTO® QUANTUM (fluralaner for extended-release injectable suspension) from Merck Animal Health to Treat and Control Asian Longhorned Tick and Gulf Coast Tick for 12 Months in Dogs

Expanded label for once-yearly parasiticide treatment for dogs now includes Haemaphysalis longicornis (Asian longhorned tick) and Amblyomma maculatum (Gulf Coast tick) for 12 months

Merck Animal Health, known as MSD Animal Health outside the United States and Canada, a division of Merck & Co., Inc., Rahway, N.J., USA (NYSE:MRK), today announced the U.S. Food and Drug Administration (FDA) approved an expanded label for BRAVECTO^® QUANTUM (fluralaner for extended-release injectable suspension) in dogs. The updated indication adds treatment and control of Asian longhorned tick (H. longicornis) and Gulf Coast tick (A. maculatum) for 12 months, when administered as a single, veterinarian‑delivered injection.

BRAVECTO QUANTUM was approved in the U.S. on July 10, 2025, and continues to be indicated to kill adult fleas, for the treatment and prevention of flea infestations, and for the treatment and control of Ixodes scapularis, Dermacentor variabilis, and Rhipicephalus sanguineus infestations for 12 months and A. americanum infestations for 8 months in dogs and puppies 6 months of age and older.

"For more than a decade, BRAVECTO has set the benchmark for extended‑duration flea and tick protection, and today's label expansion reinforces our leadership in parasiticide innovation," said Meg Conlon, DVM, executive director, U.S. Companion Animal Veterinary Services, Merck Animal Health. "With BRAVECTO QUANTUM, Merck Animal Health continues to deliver the longest‑lasting protection available in a single dose – now covering an even broader range of clinically important tick species. This advancement reflects our unwavering commitment to help veterinarians protect dogs with the most comprehensive, convenient, and science‑driven solutions on the market."

Key Information:

• What's new: BRAVECTO QUANTUM is now approved to provide 12 months of treatment and control for two additional tick species – Asian longhorned tick (H. longicornis) and Gulf Coast tick (A. maculatum) – following a single injection administered by a veterinarian. This approval expands the product's already robust label, reinforcing BRAVECTO's position as the longest‑lasting flea and tick protection available for dogs in the United States.
• Complete Parasite Protection Profile: BRAVECTO QUANTUM is indicated to kill adult fleas and for treatment and prevention of flea infestations. BRAVECTO QUANTUM also provides 12 months of protection against Asian longhorned ticks, Gulf Coast ticks, black‑legged ticks, American dog ticks, and brown dog ticks, along with 8 months of protection against lone star ticks following a single veterinarian administered‑injection.
• Why this matters: The extended‑release injectable formulation offers veterinarians and pet owners a simple, once‑yearly approach that supports improved compliance and consistent, uninterrupted protection. This label update helps veterinarians address the evolving parasite landscape, as both Asian longhorned and Gulf Coast ticks continue to expand geographically and present risks to canine health.
• Where it's available: BRAVECTO QUANTUM remains available exclusively through licensed veterinarians, ensuring appropriate in‑clinic administration, guidance, and support.

The expanded indication underscores Merck Animal Health's continued leadership in delivering innovative, extended‑duration parasite protection solutions. With BRAVECTO QUANTUM, veterinarians have an unmatched, once‑yearly option that now defends dogs against an even broader range of ticks – supporting year‑round protection and helping meet the evolving needs of pets and the people who care for them. For more information, visit us.bravecto.com or follow BRAVECTO on Instagram @bravecto.us.

About BRAVECTO^®

Since its introduction in 2014, BRAVECTO has provided longer-lasting flea and tick protection, with more than 450 million doses distributed in 100 countries over eight years. BRAVECTO is available in a variety of formulations, including products for both dogs and cats.

The flea lifecycle can last as long as 12 weeks, and monthly treatments may leave gaps in protection. Providing pets with continuous flea and tick protection is essential – whether the pet goes outside or not. Contrary to popular belief among pet owners, fleas and ticks are not only active in the spring and summer months and are a year-round risk. Fleas and ticks can easily latch onto dogs and cats and can spread serious diseases. Fleas are the most common external parasite found on pets. BRAVECTO products are available through licensed veterinarians.

About Merck Animal Health

Merck Animal Health, a division of Merck & Co., Inc., Rahway, N.J., USA, is a global animal health business committed to The Science of Healthier Animals™. For more than 130 years, we have pioneered groundbreaking science. Today, we are driven by continuous innovation to develop breakthrough medicines, vaccines and technology. Rooted in direct experience on the farm and in the clinic, we work hand in hand with our customers every step of the way. Our singular focus is to empower those who care for animals, helping them manage their vital responsibility with confidence. Because when it comes to animal health, no one sees it like we do. For more information, visit www.merck-animal-health.com and connect with us on LinkedIn, Facebook, X (formerly Twitter) and Instagram.

Forward-Looking Statement of Merck & Co., Inc., Rahway, N.J., USA

This news release of Merck & Co., Inc., Rahway, N.J., USA (the "company") includes "forward-looking statements" within the meaning of the safe harbor provisions of the U.S. Private Securities Litigation Reform Act of 1995. These statements are based upon the current beliefs and expectations of the company's management and are subject to significant risks and uncertainties. There can be no guarantees with respect to pipeline candidates that the candidates will receive the necessary regulatory approvals or that they will prove to be commercially successful. If underlying assumptions prove inaccurate or risks or uncertainties materialize, actual results may differ materially from those set forth in the forward-looking statements.

Risks and uncertainties include but are not limited to, general industry conditions and competition; general economic factors, including interest rate and currency exchange rate fluctuations; the impact of pharmaceutical industry regulation and health care legislation in the United States and internationally; global trends toward health care cost containment; technological advances, new products and patents attained by competitors; challenges inherent in new product development, including obtaining regulatory approval; the company's ability to accurately predict future market conditions; manufacturing difficulties or delays; financial instability of international economies and sovereign risk; dependence on the effectiveness of the company's patents and other protections for innovative products; and the exposure to litigation, including patent litigation, and/or regulatory actions.

The company undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events or otherwise. Additional factors that could cause results to differ materially from those described in the forward-looking statements can be found in the company's Annual Report on Form 10-K for the year ended December 31, 2025 and the company's other filings with the Securities and Exchange Commission (SEC) available at the SEC's Internet site (www.sec.gov).

FAQ:

• What changed with today's approval?
  • The BRAVECTO QUANTUM label now includes treatment and control of H. longicornis (Asian longhorned tick) and A. maculatum (Gulf Coast tick) for 12 months following a single injection administered by a veterinarian, in addition to existing indications (fleas and other listed tick species) and the 8‑month indication for A. americanum (lone star tick).
• Why focus on Asian longhorned and Gulf Coast ticks?
  • These ticks are clinically relevant and expanding in geographic range. Adding them strengthens year‑round, single‑dose tick control options for more dogs across more U.S. regions.
• How is BRAVECTO QUANTUM administered?
  • BRAVECTO QUANTUM is administered via a single subcutaneous injection delivered by a licensed veterinarian.
• Is this the same BRAVECTO formulation that was introduced in 2025?
  • Yes. BRAVECTO QUANTUM remains the once‑yearly fluralaner extended‑release injectable. Today's update expands the label's tick species coverage.
• Is BRAVECTO QUANTUM safe?
  • BRAVECTO QUANTUM has undergone extensive safety testing. In fact, safety was demonstrated when dosed at 5 times the recommended dose every 4 months for a total of 6 doses. In a U.S. field study with client owned dogs, 0.9% (2 out of 225 dogs) experienced seizures. This rate is consistent with estimates reported in the general dog population. BRAVECTO QUANTUM (fluralaner) is a member of the isoxazoline class, which has been associated with neurologic adverse reactions, including tremors, ataxia, and seizures. Use with caution in dogs with a history of seizures or neurologic disorders.
• Where can veterinarians find full prescribing information?
  • Please see the Prescribing Information (PI) here and consult Merck Animal Health for training and ordering support.
• Can cats receive BRAVECTO QUANTUM?
  • No. BRAVECTO QUANTUM is approved only for dogs and puppies 6 months of age and older and must be administered by a licensed veterinarian. It is not approved for use in cats. For cats, Merck Animal Health offers BRAVECTO^® Plus, a topical formulation that provides broad‑spectrum, extended‑duration protection against fleas, ticks, and internal parasites.

IMPORTANT SAFETY INFORMATION:

BRAVECTO (fluralaner) Chews for Dogs: The most commonly reported adverse reactions include vomiting, lethargy, diarrhea, anorexia and pruritus. In some cases, adverse events have been reported following use in breeding females. BRAVECTO Chews has not been shown to be effective for 12-weeks' duration in puppies less than 6 months of age. BRAVECTO Chews is not effective against lone star ticks beyond 8 weeks of dosing. Indicated for dogs 6 months of age and older. BRAVECTO 1-MONTH (fluralaner) Chews: The most commonly reported adverse reactions include itching, diarrhea, vomiting, decreased appetite, elevated ALT, lethargy, and weight loss. Not effective against lone star ticks in puppies less than 6 months of age. Indicated for dogs 8 weeks of age and older. BRAVECTO (fluralaner topical solution) for Dogs: The most commonly reported adverse reactions include vomiting, hair loss, diarrhea, lethargy, decreased appetite, and moist dermatitis/rash. BRAVECTO Topical Solution for Dogs has not been shown to be effective for 12-weeks' duration in puppies less than 6 months of age. BRAVECTO Topical Solution for Dogs is not effective against lone star ticks beyond 8 weeks of dosing. For topical use only. Avoid oral ingestion. Indicated for dogs 6 months of age and older. BRAVECTO QUANTUM (fluralaner for extended-release injectable suspension) for Dogs: The most commonly reported adverse reactions in a US field study included lethargy, decreased appetite, vomiting, diarrhea, elevated liver enzymes and pruritus. BRAVECTO QUANTUM is not effective against lone star ticks beyond 8 months of dosing. Indicated for dogs 6 months of age and older.

BRAVECTO (fluralaner topical solution) for Cats: The most commonly reported adverse reactions include vomiting, itching, diarrhea, hair loss, decreased appetite, lethargy, and scabs/ulcerated lesions. BRAVECTO Topical Solution for Cats is not effective against American dog ticks beyond 8 weeks of dosing. BRAVECTO Topical Solution for Cats has not been shown to be effective for 12-weeks' duration in kittens less than 6 months of age. The safety of BRAVECTO Topical Solution for Cats have not been established in breeding, pregnant and lactating cats. For topical use only. Avoid oral ingestion. Indicated for cats 6 months of age and older. BRAVECTO PLUS (fluralaner and moxidectin topical solution) for Cats: The most commonly reported adverse reactions include vomiting, hair loss, itching, diarrhea, lethargy, dry skin, elevated ALT, and hypersalivation. BRAVECTO PLUS has not been shown to be effective for 2 months in kittens less than 6 months of age. Use with caution in cats that are heartworm positive. The effectiveness of BRAVECTO PLUS to prevent heartworm disease after bathing or water immersion has not been evaluated. The safety of BRAVECTO PLUS have not been established in breeding, pregnant and lactating cats. Indicated for cats 6 months of age and older.

All BRAVECTO products contain fluralaner, which is a member of the isoxazoline class. This class has been associated with neurologic adverse reactions including tremors, ataxia, and seizures. Seizures have been reported in dogs receiving isoxazoline class drugs, even in dogs without a history of seizures. Use with caution in dogs with a history of seizures or neurologic disorders. Neurologic adverse reactions have been reported in cats receiving isoxazoline class drugs, even in cats without a history of neurologic disorders. Use with caution in cats with a history of neurologic disorders.

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