I have discussed osteoarthritis (OA) a lot, including how common arthritis is in dogs and cats, and how it can greatly affect comfort, mobility, and quality of life. I have also previously covered Librela (bedinvetmab) for dogs and Solensia (frunevetmab) for cats, including growing concerns about possible serious side effects linked to this class of medications.
These medications work by blocking nerve growth factor (NGF), which is involved in pain signaling. Many pets have shown improvement in comfort and mobility while receiving these injections, and millions of doses have been used worldwide. However, veterinarians and researchers are continuing to investigate reports of rapid joint deterioration and unusual bone and joint changes in some patients receiving these medications.
This new article by von Pfeil et al discusses reports of “rapidly progressive osteoarthritis” (RPOA). This means the joints may break down much faster than normal arthritis would usually progress. In people, similar anti-NGF drugs were studied years ago, but they were never approved because of concerns about severe joint damage.
The authors explain that some dogs receiving Librela developed major joint problems, including:
• Severe bone changes
• Joint instability
• Bone destruction
• Fractures around joints
• Large amounts of abnormal bone formation
• Joint collapse in some cases
In some dogs, these problems happened after only one or two injections.
In others, the changes developed more slowly after many monthly injections.
The article also discusses a few cats that may have developed similar problems after receiving Solensia. One cat developed severe damage in both ankle joints only two months after treatment started. Testing did not find infection or immune disease, making the medication-related changes more concerning.
One important point from the paper is that these joint problems may happen even in joints that did not seem severely arthritic at the start. That means some joints could have “silent” or early disease that worsens quickly after treatment.
Researchers do not fully understand why this may happen. NGF does more than just control pain. It also appears to help with bone healing, cartilage health, and joint stability. Blocking NGF may interfere with the body’s ability to protect and repair joints normally.
The article emphasizes that veterinarians should carefully monitor pets receiving these medications. If a pet suddenly worsens, develops a new limp, becomes unstable, or seems painful despite treatment, a full examination and imaging should be considered.
The authors also encourage veterinarians to report suspected side effects so the profession can better understand the risks and identify which patients may be more vulnerable.
Full article here: Veterinary and Comparative Orthopaedics and Traumatology Editorial
drbrunke 
Leave a comment