Merck Animal Health Presents New Data Highlighting Commitment to the Development and Study of Parasite Prevention and Treatment for Dogs at the 2025 World Association for the Advancement of Veterinary Parasitology Congress 

Data to showcase depth and breadth of the BRAVECTO® (fluralaner) portfolio including the injectable and oral endectocide combination formulations

RAHWAY, N.J., August 18, 2025 – Merck Animal Health, known as MSD Animal Health outside  of the United States and Canada, a division of Merck & Co., Inc., Rahway, N.J., USA (NYSE:MRK), today announced it will present multiple studies in support of the BRAVECTO® fluralaner portfolio at the 2025 World Association for the Advancement of Veterinary Parasitology Congress (WAAVP) in Curitiba, Brazil, August 17-21, 2025. Data highlight Merck Animal Health’s commitment to rapidly advance research across parasite prevention and treatment and build on its portfolio of established parasiticides.

“The new data we are presenting at WAAVP spotlight our commitment to parasitology research as we develop novel treatment approaches in our ongoing work to improve parasite prevention and treatment,” said Rafael Chiummo, Ph.D., Associate Director, Clinical Research, Latin America, Merck Animal Health. “Merck Animal Health is pioneering innovation in parasitology through research and development that benefits dogs and the people that care for them.”

BRAVECTO 365

A study titled “The Effectiveness of BRAVECTO® 365 (fluralaner 150 mg/ml suspension for injection) for the Control of Fleas on Naturally Infested Client-Owned Dogs in Brazil” evaluated the efficacy of the injectable formulation of BRAVECTO in treating naturally infested dogs with Ctenocephalides felis fleas in Brazil and found a 100% reduction in live fleas from Day 10 and that efficacy remained at or above 99.8% for 365 days for one full year. All dogs completed the trial without any treatment-related adverse events. This study demonstrated the high efficacy and safety of the injectable formulation of BRAVECTO against flea infestations on dogs over an entire year.

A study title “Long-Term Efficacy of BRAVECTO 365 (fluralaner 150 mg/ml suspension for injection) Against Rhipicephalus sanguineus (sensu lato) Ticks on Client-Owned Dogs in Brazil” assessed the effectiveness of BRAVECTO 365, administered subcutaneously at 15 mg fluralaner/kg body weight, in treating dogs naturally infested with Rhipicephalus sanguineus (commonly called Brown Dog ticks). Forty client-owned dogs with confirmed tick infestations received a single dose, and tick counts were monitored from before treatment up to 365 days post-treatment. Results demonstrated a ≥99.8% reduction in live ticks from Day 7 through Day 365.

BRAVECTO 1 MONTH TRIPLE

A study titled “Evaluation of a Chewable Tablet Containing Fluralaner + Moxidectin + Pyrantel for the Treatment of Demodectic Mange in Dogs” assessed the efficacy and safety of an oral combination tablet containing fluralaner, moxidectin, and pyrantel for treating Demodex canis mite infestations in naturally affected dogs. Twelve dogs confirmed positive for mites received two doses of the tablet 30 days apart, with mite counts monitored at multiple intervals up to 90 days. Results showed a progressive reduction in mite counts, reaching 99% by Day 33 and 100% from Day 37 onward. No treatment-related adverse effects were observed. The findings indicate that this combination tablet is both safe and highly effective for managing demodectic mange in dogs when two doses are administered at a monthly interval at the recommended dosage.

Additional data being presented from the Merck Animal Health BRAVECTO portfolio:

BRAVECTO 365:

  • Clinical Evaluation of BRAVECTO® 365 (Fluralaner 150 Mg/ml Suspension for Injection) for Treating Naturally Infested Dogs with Otodectic Mange
  • Evaluation Of BRAVECTO® 365 (Fluralaner 150 Mg/ml Suspension for Injection) for the Treatment of Demodectic Mange in Dogs
  • Efficacy Against Ticks and Fleas Artificial Infestation (One Year Long)
  • Onset of Efficacy Against Fleas and Ticks Artificial Infestation

BRAVECTO 1 MONTH TRIPLE:

  • Successful Treatment of Canine Roundworm Infections with a Single Administration of a Fluralaner, Moxidectin and Pyrantel Chewable Tablet in a Non-Terminal Study Design
  • Successful Treatment of Experimental Canine Hookworm Infections with a Single Administration of a Fluralaner, Moxidectin and Pyrantel Chewable Tablet in a Non-Terminal Study Design
  • Field Study on the Effectiveness of Fluralaner, Moxidectin, and Pyrantel in Preventing Heartworm Infection in Client-Owned Dogs

About BRAVECTO®

Since its introduction in 2014, BRAVECTO has provided longer-lasting flea and tick protection, with more than 350 million doses distributed in 100 countries over a decade. 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.

Important Safety Information

BRAVECTO QUANTUM: indicated for the treatment and prevention of flea infestations (Ctenocephalides felis) and for the treatment and control of tick infestations [Ixodes scapularis (black-legged tick), Dermacentor variabilis (American dog tick) and Rhipicephalus sanguineus (brown dog tick)] for 12 months in dogs and puppies 6 months of age and older. BRAVECTO QUANTUM is also indicated for the treatment and control of Amblyomma americanum (lone star tick) infestations for 8 months in dogs and puppies 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. Fluralaner 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. The safety of BRAVECTO QUANTUM has not been evaluated in breeding, pregnant and lactating dogs. In some cases, adverse events have been reported following use of BRAVECTO (fluralaner) Chews in breeding females. For use in dogs and puppies 6 months of age and older.

BRAVECTO 1-MONTH Chews: indicated for dogs 8 weeks of age and older. The most commonly reported adverse reactions include itching, diarrhea, vomiting, decreased appetite, elevated ALT, lethargy, and weight loss. BRAVECTO 1-MONTH is not effective against A. americanum in puppies less than 6 months of age. BRAVECTO 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 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 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 PLUS 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.

BRAVECTO has not been shown to be effective for 12-weeks’ duration in puppies or kittens less than 6 months of age. BRAVECTO Chews and Topical Solution for dogs is not effective against the lone star tick beyond 8 weeks of dosing. BRAVECTO Topical Solution for Dogs and Cats and BRAVECTO PLUS for cats are for topical use only. Avoid oral ingestion.

The safety of BRAVECTO Topical Solution for Cats and BRAVECTO PLUS has not been established in breeding, pregnant, and lactating cats.

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.

About Merck Animal Health

At Merck, known as MSD outside of the United States and Canada, we are unified around our purpose: We use the power of leading-edge science to save and improve lives around the world. For more than a century, we’ve been at the forefront of research, bringing forward medicines, vaccines and innovative health solutions for the world’s most challenging diseases. Merck Animal Health, a division of Merck & Co., Inc., Rahway, N.J., USA, is the global animal health business of Merck. Through its commitment to The Science of Healthier Animals®, Merck Animal Health offers veterinarians, farmers, producers, pet owners and governments one of the widest ranges of veterinary pharmaceuticals, vaccines and health management solutions and services as well as an extensive suite of connected technology that includes identification, traceability and monitoring products. Merck Animal Health is dedicated to preserving and improving the health, well-being and performance of animals and the people who care for them. It invests extensively in dynamic and comprehensive R&D resources and a modern, global supply chain. Merck Animal Health is present in more than 50 countries, while its products are available in some 150 markets. 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, 2024 and the company’s other filings with the Securities and Exchange Commission (SEC) available at the SEC’s Internet site (www.sec.gov).