March 2, 2020

The U.S. Food and Drug Administration’s Center for Veterinary Medicine today announced the approval of Simparica Trio (sarolaner, moxidectin, and pyrantel) with the following indications:

• Prevent heartworm disease caused by Dirofilaria immitis;
• Kill adult fleas, treat and prevent flea infestations;
• Treat and control tick infestations with the lone star tick, Gulf Coast tick, American dog tick, black-legged tick, and brown dog tick; and
• Treat and control roundworm and adult hookworm infections. 

Simparica Trio chewable tablets are approved as a once-a-month treatment for these indications in dogs and puppies eight weeks of age and older that weigh 2.8 pounds or more.

FDA has already approved each of the three main active ingredients for their separate indications, but FDA is approving Simparica Trio as a novel combination of these three antiparasitic drugs that combines each drug’s indications.

The three active ingredients are:

• Sarolaner was first approved by the FDA in 2016 to treat and control flea and tick infestations. 
• Moxidectin was first approved by the FDA in 1997 for the prevention of heartworm disease in dogs. 
• Pyrantel Pamoate was first approved in 1977 for the treatment and control of adult roundworms and adult hookworms in dogs. 

Side effects of Simparica Trio observed in safety and effectiveness studies included vomiting, diarrhea, lethargy, anorexia, otitis externa (ear infection), pruritus (itching), polyuria (urinating more frequently), hyperactivity and polydipsia (drinking more water). While neurological side effects were not observed in these studies, sarolaner, one of the active ingredients in Simparica Trio, is in the isoxazoline drug class. FDA considers these drugs to be safe and effective, but the agency has issued a public alert that, in some cases, isoxazoline products have been associated with neurologic adverse reactions, including muscle tremors, ataxia, and seizures in some dogs and cats.

Simparica Trio is available by prescription only. Because the product is indicated for the prevention of heartworm infection in dogs, prior to administering the product, a veterinary exam and blood test are necessary to ensure that a dog does not already have heartworm disease.

Zoetis Inc. of Kalamazoo, Michigan is the sponsor of Simparica Trio. 

For more information:

• Freedom of Information Summary - Simparica Trio 
• Fact Sheet for Pet Owners and Veterinarians about Potential Adverse Events Associated with Isoxazoline Flea and Tick Products
• Keep the Worms Out of Your Pet’s Heart! The Facts about Heartworm Disease 
• Safe Use of Flea and Tick Products in Pets