Anti-Nerve Growth Factor Antibody Improves Mobility in Cats with Degenerative Joint Disease

An antibody against nerve growth factor improved activity levels and pain scores in cats with degenerative joint disease in a pilot study recently published in the Journal of Veterinary Internal Medicine. The effect appeared to last about 6 weeks.

Nexvet Biopharma developed a felinized anti—nerve growth factor monoclonal antibody, NV-02 (frunevetmab), as a subcutaneous injectable to control osteoarthritis pain in cats. Nerve growth factor regulates the survival of neurons during development and activates pain pathways at inflammation sites in the adult. Previous studies have shown that anti—nerve growth factor antibody alleviates chronic pain in rodents, humans, and dogs.

The study included 34 pet cats with degenerative joint disease. Owners completed subjective client-specific outcome measure instruments and feline musculoskeletal pain indexes at the beginning of the study. Cats underwent physical examinations, radiography, and blood and urine tests. For the first 2 weeks, cats wore collar-mounted accelerometers to measure their baseline activity levels.

On day 14, each cat received a single subcutaneous injection of 0.4 mg/kg NV-02, 0.8 mg/kg NV-02, or sterile saline. Over the next 11 weeks, the investigators collected accelerometer data and the owners completed additional outcome measure assessments and pain indexes. At the end of the study, investigators repeated the physical examinations and laboratory tests. Clients completed final assessments of their cats and indicated whether they thought their cats had received NV-02 or placebo.

Activity levels measured by accelerometry were significantly higher 2 to 6 weeks after injection in cats receiving NV-02 than in cats receiving placebo. The differences between the 2 doses of NV-02 were not significant. The increase in activity during the first 3 weeks after NV-02 injection was similar to or higher than that measured after daily meloxicam treatment in an earlier study, write the authors.

Owner-assessed outcome scores significantly improved for all cats in the study, including those receiving placebo, at nearly every time point. Scores were significantly higher 3 weeks after injection (but not at other time points) in cats receiving NV-02 than in those receiving placebo. Most owners (83%) of cats receiving NV-02 correctly guessed that their cats had received treatment; only 45% correctly guessed that their cats had received placebo.

By the end of the study, mean total protein and serum globulin concentrations were significantly higher in cats receiving NV-02 than in those receiving placebo. The investigators found no association between adverse events (which were mild in 6 cats and serious in 1) and NV-02 administration.

The authors concluded that the results indicated a positive treatment effect despite the large placebo response. “We believe that the potential impact in veterinary medicine of an injection lasting approximately 6 weeks for the control of long-term pain in the cat is very positive and clinically relevant,” they write.

Nexvet Biopharma supported the study. The lead author received funding from the National Institutes of Health. One of the authors is a paid consultant for Nexvet, and another is a Nexvet employee.

Dr. Laurie Anne Walden received her doctorate in veterinary medicine from North Carolina State University. After an internship in small animal medicine and surgery at Auburn University, she returned to North Carolina, where she has been in small animal primary care practice for over 20 years. Dr. Walden is also a board-certified editor in the life sciences and owner of Walden Medical Writing, LLC.