
RAHWAY, N.J. – 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 commercial availability of CIRCUMVENT® CL vaccine, a ready-to-use vaccine formulated to protect pigs three weeks of age and older against disease caused by Porcine Circovirus (PCV) Types 2a and 2d and Lawsonia intracellularis.
CIRCUMVENT CL is designed to simplify herd health programs by delivering dual protection in a ready-to-use formulation that requires no mixing or reconstituting. This new product complements Merck Animal Health’s existing swine portfolio, including CIRCUMVENT CML, a single-dose, ready-to-use vaccine that protects against PCV Types 2a and 2d, Mycoplasma hyopneumoniae (M. hyopneumoniae) and Lawsonia intracellularis in pigs three weeks of age and older, which was introduced in 2023. CIRCUMVENT CL omits the mycoplasma component to meet the needs of herds that are now M. hyopneumoniae-negative while maintaining robust protection against PCV and Lawsonia intracellularis.
“Merck Animal Health is committed to delivering innovative, practical solutions that help veterinarians and producers protect herd health while streamlining on-farm operations,” said Brett O’Brien, V.M.D., swine technical services, Merck Animal Health. “CIRCUMVENT CL provides trusted protection against two of the most significant enteric and systemic disease agents impacting swine production in a ready-to-use formulation. By offering options such as CIRCUMVENT CML and CIRCUMVENT CL, we enable tailored vaccination strategies that simplify vaccine handling and administration.”
Key product benefits of CIRCUMVENT CL include:
- Dual protection: Effective against disease caused by Porcine Circovirus Types 2a and 2d and Lawsonia intracellularis in pigs three weeks of age or older.
- Ready-to-use: Single-bottle presentation requires no mixing or reconstituting, helping to reduce preparation time and potential handling errors.
- Flexible herd options: Designed for use in herds where M. hyopneumoniae vaccination is not required, providing a targeted solution for M .hyopneumoniae-negative operations.
- Complementary portfolio: Adds to Merck Animal Health’s CIRCUMVENT family, enabling veterinarians to choose the formulation that best fits herd health status and management goals.
CIRCUMVENT CL is available in 50- and 250-dose presentations. A 500-dose presentation will be available in Q1 2026. For more information, contact your Merck Animal Health sales or technical services representative or visit https://www.merck-animal-health usa.com/species/swine.
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.
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