11 June 2012


Merck Animal Health Announces ACTIVYL® AND ACTIVYL® TICK PLUS
First Flea Products to Use Bioactivation

SUMMIT, N.J., June 11, 2012 – Merck Animal Health, a leading provider of innovative animal health products and services, today announced the U.S. launch of Activyl® and Activyl® Tick Plus. Activyl treats and prevents flea infestations in dogs and cats; Activyl Tick Plus, exclusively for dogs, controls both fleas and ticks. Activyl and Activyl Tick Plus will be available only through licensed veterinarians.

Activyl is the first flea control product to utilize metabolic activation, or bioactivation of the active ingredient, to kill fleas. It is a topical, once-a-month ectoparasiticide containing indoxacarb, a compound never before used in animal health, with no known resistance in fleas. Following application, indoxacarb enters the flea by contact or ingestion and is converted by enzymes in the flea to an active highly insecticidal metabolite. Fleas stop feeding, become paralyzed and die within hours.

Activyl not only kills adult fleas, but also disrupts the flea’s life cycle by inhibiting the development of flea larvae in the pet’s surroundings. This aids in the environmental control of flea infestation and helps prevent re-infestation for up to a full month. Activyl is able to control developing stages of the flea in the environment, so there is no need for additional insect growth regulators. Activyl may also be used as part of a treatment strategy for flea allergy dermatitis.

"This is a significant addition to our methods of controlling fleas among dogs and cats. The new molecule present in Activyl will help veterinarians and pet owners manage this chronic problem," said Kathleen Heaney, D.V.M., marketing liaison manager for Merck Animal Health.

In laboratory studies, Activyl was shown to start killing fleas within hours of application and to keep killing newly arriving fleas within 8-12 hours for a full four weeks.1 In field studies, Activyl outperformed fipronil-containing products, making more dogs and cats flea free.2,3

Dispensed in easy to use, single-application pipettes, Activyl is fragrance-free, dries quickly and remains effective following shampooing, swimming and exposure to sunlight. Five pipette sizes are available for small to extra-large dogs and two sizes are available for cats, small and large.

Activyl Tick Plus is exclusively for dogs and combines the effective flea control of Activyl with long-lasting protection against ticks. In addition to indoxacarb, Activyl Tick Plus contains permethrin, an acaricide with proven efficacy against ticks, which provides the added benefit, of repellent activity, to keep ticks off dogs in the first place. Studies have shown Activyl Tick Plus to be more than 96 percent effective against four tick species known to carry such diseases as Rocky Mountain spotted fever, ehrlichiosis and Lyme disease.4

Once applied, Activyl Tick Plus continues to kill fleas and repel and kill ticks for up to four weeks and remains effective following swimming and exposure to rain or sunlight. The product is also dispensed in easy to use, single application pipettes in a variety of sizes. It is approved for use in in puppies as young as eight weeks of age, weighing more than four pounds.

Through the Merck Track & Trace System, the veterinary exclusivity of Activyl and Activyl Tick Plus is enforced and ensured, protecting veterinarians’ practices and preserving their role as the pet health experts.

About Merck Animal Health
Today's Merck is a global healthcare leader working to help the world be well. Merck Animal Health, known as MSD Animal Health outside the United States and Canada, is the global animal health business unit of Merck. Merck Animal Health offers veterinarians, farmers, pet owners and governments one of the widest ranges of veterinary pharmaceuticals, vaccines and health management solutions and services. Merck Animal Health is dedicated to preserving and improving the health, well-being and performance of animals. 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.

Important safety information about Activyl and Activyl Tick Plus
Activyl Tick Plus must not be used on cats.


  1. Merck Animal Health-data on file – N09-055-01.
  2. Flochay-Sigognault A, et al. Field efficacy of a spot-on formulation of indoxacarb for flea control in dogs and cats. Poster presented at: 23rd International Congress of the World Association for the Advancement of Veterinary Parasitology (WAAVP), 21-25 August 2011, Buenos Aires, Argentina.
  3. Merck Animal Health – data on file-FID 906.
  4. Merck Animal Health – data on file: NO8-212-01, E08-124-01, N09-005-01, N08-202-01.

Legal Notes
MERCK and MSD are trademarks of Merck, Sharpe & Dohme Corp., a subsidiary of Merck & Co., Inc., Whitehouse Station NJ, USA.

ACTIVYL® and ACTIVYL® TICK PLUS are trademarks of Intervet International B.V. or affiliated companies or licensors and are protected by copyrights, trademark and other intellectual property laws. Copyright © 2012 Intervet International B.V., a subsidiary of Merck & Co., Inc., Summit, NJ, USA. All rights reserved. This press release contains information on veterinary products based on international registration dossiers and may refer to products that are either not available in your country or are marketed under a different trade name. In addition, the approved indications as well as safety and efficacy data for a specific product may be different depending on local regulations and approvals. For more information, read the product labeling that applies to your country or contact your local Merck Animal Health/MSD Animal Health representative.