What killed their pets? Owners blame meds, but vets aren’t sure

livemint.com:

Phil Jordan’s 12-year-old rescue dog Daisy struggled with a stiff right rear hip. When the new arthritis drug Librela became available, Jordan and his wife decided to try it. About two weeks after the first injection in January, however, Daisy wobbled on both hips and limped.

A week after her second dose, the dog couldn’t walk, became lethargic and lost her appetite. She gained back some mobility, but her kidney function plunged. In March, the Jordan family euthanized their dog.

“There’s a tremendous amount of guilt that we feel," said Jordan, an economist from Wrentham, Mass. Librela and a similar treatment for cats were the first antibody drugs for pets approved by the Food and Drug Administration. They promised to relieve a painful arthritis in animals and become an important new franchise for maker Zoetis, the world’s largest animal-health company by sales.

Now they are at the center of a medical mystery. Some pet owners blame the drugs for sickening their animals, some of which then died. Was it the drugs? Were they being used the wrong way? Or were other illnesses afflicting the pets at fault? Health regulators in the U.S.

and Europe—which have received thousands of reports of side effects—are conducting reviews. Some veterinarians are refining use of Librela and the cat therapy Solensia. Wall Street analysts have asked Zoetis about the pet owners’ complaints.

Zoetis says the medicines are safe, with reports of side effects representing well less than 1% of the more than 18 million shots of both drugs combined administered to date in the U.S. and abroad. Many veterinarians and pet owners have also reported success with the drugs.