Canine Arthritis Therapies Face Criticism Following Reports of Severe and Potentially Lethal Adverse Reactions
Canine Arthritis Therapies Face Criticism Following Reports of Severe and Potentially Lethal Adverse Reactions
A commonly used arthritis medication for dogs, Librela, could be more hazardous than we initially perceived. This week, the Food and Drug Administration (FDA) disclosed several severe adverse effects and fatalities associated with Librela, a drug recently authorized for market release.
On Monday, the FDA's Center for Veterinary Medicine (CVM) issued a letter to veterinarians, detailing the findings from its investigation into Librela. The FDA recognized numerous serious adverse events that were linked to the drug's usage, such as seizures and muscle function loss; multiple dogs reportedly died or had to be euthanized due to these complications. The agency has proposed that the manufacturer ought to modify its label to include these potential side effects and encourages vets and the public to report any associated adverse events.
Librela's active ingredient, bedinvetmab, is a human-made antibody developed by Zoetis. In 2023, the FDA approved it to treat osteoarthritis in dogs. Delivered through monthly injections, the drug targets and suppresses a protein involved in pain regulation, called Canine Nerve Growth Factor (NGF). The drug aims to reduce NGF levels, which tend to be higher in dogs diagnosed with osteoarthritis. Librela was the first monoclonal antibody-based drug approved for use in dogs and the second drug authorized for use in pets.
At its approval, some popular side-effects connected to Librela were urinary tract infections, rash, vomiting, and weight loss. As with other approved drugs, the FDA has monitored reports of adverse events related to Librela's usage submitted by veterinarians and pet owners. However, some dog owners have reported severe—even fatal—symptoms in their pets after starting Librela use.
As of March 2024, there have been 3,674 adverse event reports linked to Librela, according to the FDA. Older dogs have been more prone to these adverse events, which resonates with the increased osteoarthritis risk associated with age. The FDA identified numerous potential serious adverse events not currently mentioned in the drug's label, such as ataxia (muscle control problems), seizures, diarrhea, and paralysis. Dogs have tragically died or been euthanized shortly after experiencing these severe adverse events.
One case file, for example, documented the development of ataxia in a 10-year-old Great Pyrenees one hour after Librela administration. With each consecutive day, the dog developed incontinence, hindlimb lameness that spread to the forelimbs, and ultimately paralysis. The dog passed away four days after taking the drug.
The FDA has underscored that the reported adverse events have not been definitively linked to Librela at this time, although no causative evidence connecting these events to Librela has been dismissed either.
Zoetis issued a statement in response to the FDA's letter. The company criticized some media outlets for allegedly sensationalizing the FDA's communication as a "warning," rather than an "informational update" for veterinarians and the general public. Zoetis also contended, based on data from the European Union, that any identified adverse events related to Librela are unlikely to be a frequent occurrence.
“We believe in Librela’s safety and efficacy and remain committed to supporting veterinarians and pet owners in providing dogs with less pain and improved mobility,” Zoetis states.
While Zoetis continues to endorse its drug, it has mentioned its intention to discuss potential labeling modifications with the FDA. The FDA encourages veterinarians and dog owners to keep reporting adverse events connected to the drug's use.
Given the concerns surrounding Librela's adverse effects, the future of arthritis treatment in animals could involve a more rigorous examination of new drugs using advanced technology and scientific methods. It's crucial for pharmaceutical companies to invest in thorough research and monitoring to ensure the safety and effectiveness of their products.
In light of the recent findings, the FDA's scrutiny of animal health medication could lead to stricter regulations and more stringent requirements for drug approval, aiming to protect pets from potential harm. This could ultimately benefit both animals and their owners, providing reassurance that approved treatments are both safe and effective.