First-of-its-kind next-generation rabies vaccines provide veterinarians with an innovative, non-adjuvanted option delivering three-year protection for dogs and cats

RAHWAY, N.J., November 2, 2026 - 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 the U.S. availability of NOBIVAC NXT^®1-Rabies and NOBIVAC NXT^® 3-Rabies, next-generation rabies vaccines effective for vaccination of healthy cats and dogs 12 weeks of age or older against rabies. NOBIVAC NXT 3-Rabies is designed to help protect cats and dogs against rabies and offers the convenience of a three-year duration of immunity after a repeat dose.

The U.S. introduction of NOBIVAC NXT Rabies marks an important milestone in expanding access to Merck Animal Health's innovative NOBIVAC NXT platform for companion animal veterinarians. Rabies remains one of the most serious infectious diseases affecting both animals and humans and is almost always fatal once clinical signs appear.

"NOBIVAC NXT represents the next generation of vaccine innovation from Merck Animal Health, combining advanced technology with our unwavering commitment to preventive care," said Meg Conlon, DVM, executive director, U.S. companion animal veterinary services, Merck Animal Health. "Vaccination remains one of the most important steps pet owners can take to protect the health of their dogs and cats. With NOBIVAC NXT Rabies, veterinarians now have an innovative option designed to provide trusted rabies protection while supporting a positive vaccination experience for pets, veterinary teams and pet owners alike. As expectations for companion animal care continue to evolve, we are proud to bring this advancement to veterinary practices across the United States."

Built on Merck Animal Health's NOBIVAC NXT platform, the vaccines reflect the company's ongoing commitment to developing innovative solutions that help veterinarians protect pets, support preventive healthcare and strengthen the human-animal bond.

Key Information
Why NOBIVAC NXT^® Rabies is needed: Rabies remains one of the deadliest infectious diseases affecting animals and humans worldwide. While highly preventable through routine vaccination, the disease continues to pose a significant public health risk and is almost always fatal once clinical signs appear. Vaccination of dogs and cats is a critical component of rabies prevention and plays an important role in protecting both animal and human health.

What makes NOBIVAC NXT Rabies different: NOBIVAC NXT^® 1-Rabies and NOBIVAC NXT^® 3-Rabies are built on Merck Animal Health's next-generation vaccine platform and provide one- or three-year rabies protection for cats and dogs. The vaccines are non-adjuvanted, preservative-free, antibiotic-free and thimerosal-free and are designed to provide veterinarians with an innovative option for rabies prevention while maintaining the trusted protection associated with the NOBIVAC portfolio. Delivered in a low-volume 0.5 mL dose, NOBIVAC NXT Rabies was developed with both protection and the vaccination experience in mind, supporting comfort and ease of administration for veterinary teams and patients.

Why vaccination matters: Routine vaccination plays a critical role in protecting pets, supporting public health and helping pet owners avoid the devastating consequences of rabies infection. By working closely with their veterinarian and maintaining recommended vaccination schedules, pet owners can help ensure their dogs and cats remain protected throughout their lives.

Merck Animal Health's commitment to rabies prevention: As the maker of NOBIVAC vaccines, Merck Animal Health has a long-standing commitment to advancing rabies prevention through scientific innovation, veterinary education and partnerships focused on reducing the burden of rabies worldwide and improving the health and well-being of animals.

"Vaccination remains a cornerstone of rabies prevention, but advances in vaccine technology also create opportunities to improve the vaccination experience," said Laura Greene, DVM, DACVIM, internal veterinary medicine specialist, Merck Animal Health. "NOBIVAC NXT Rabies builds on that approach, offering veterinarians a rabies vaccine developed on a platform designed with both protection and the vaccination experience in mind, including a low-volume 0.5 mL dose that supports comfort and convenience during routine preventive care."

Commitment to Rabies Prevention

Commitment to Rabies Prevention
For decades, Merck Animal Health has supported efforts to advance rabies awareness, prevention and education around the world. Through scientific innovation and collaboration with veterinarians, public health professionals and animal health organizations, the company remains committed to helping reduce the impact of rabies and supporting healthier futures for pets and the people who care for them.

Beyond its commitment to vaccine innovation, Merck Animal Health continues to support rabies prevention initiatives and collaborations aimed at expanding awareness, advancing education and increasing access to vaccination in communities around the world. For more information about NOBIVAC^® vaccines, visit www.nobivac.com.

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.

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