Izenivetmab is available for veterinary use in the EU

• Izenivetmab has received regulatory approvals in the European Union, the United Kingdom and Canada. This is the first treatment for chronic pain associated with osteoarthritis in dogs to be administered quarterly. Therapy offers three months of osteoarthritis pain relief for dogs with a single injection.
• Izenivetmab was well-tolerated at clinical and high doses with no significant adverse effects. Treatment-emergent immunogenicity was rare and had no impact on safety or clinical signs.

Canine osteoarthritis (OA) remains one of the most common chronic conditions seen in general small-animal practice. Epidemiological data indicate that up to 40% of dogs may have radiographic OA. The disease’s impact extending well beyond joint pathology to affect mobility, sleep quality, behaviour and social interaction. This degenerative joint disease is a significant factor in euthanasia decisions in dogs. Because OA is progressive and incurable, management strategies have historically centred on multimodal pain control. NSAIDs dominated this therapeutics for decades before the arrival of monoclonal antibody.

Izenivetmab structure and mechanism of action

Izenivetmab (Lenivia) is a monoclonal antibody targeted Nerve Growth Factor (NGF). This biologic drug was designed for veterinary use by Zoetis. Izenivetmab binds to a different site on the NGF molecule than the anti-NGF antibodies already commercialised for dogs, a structural distinction the company links to its extended three-month dosing interval.

NGF is a critical mediator of nociception, is an analgesic therapeutic target. It has been established to play a role in sensitizing peripheral pain receptors and amplifying pain signals in joint disease. By binding NGF and neutralising its downstream signalling, izenivetmab is designed to interrupt this pain pathway at its source. Instead of acting through the prostaglandin-mediated mechanisms used by traditional NSAIDs such as carprofen or mavacoxib.

Izenivetmab therapy is administered subcutaneously every three months, making it the longest-lasting anti-NGF treatment option Zoetis has launched for the treatment of OA in dogs. It is the first treatment specifically designed to extend dosing beyond the monthly interval used by the previous-generation drug, bedinvetmab.

Clinical trial results

Summary of pivotal nine-month European field trials demonstrating treatment success in 37.3% of dogs at Day 90 (compared to 22.6% for placebo) with clinical onset observable as early as Day 7 post-injection. It reviews controlled Beagle safety trials confirming tolerability at extreme dose multiples (up to 120× monthly) without safety impacts, immunotoxic disruptions, or joint-related progressive lesions. Neutralizing antibodies were detected in 8 of the 10 treated ADA-positive dogs. Immunogenicity was observed in 3.46% of dogs (compared to 2.83% for placebo).

Safety and efficacy of izenivetmab were assessed in the same European study. Dogs receiving the therapy showed a sustained reduction in pain and improved mobility, with treatment effects observed as early as day seven following the first injection.

Because clinical trials of other anti-NGF monoclonal antibodies in humans (such as tanezumab) have historically been associated with a joint-related adverse event known as Rapidly Progressive Osteoarthritis (RPOA), joint safety was a critical focus of the target animal safety program. To investigate this theoretical risk, researchers incorporated detailed pre- and post-study radiographic, ex vivo Faxitron, and expanded microscopic analyses of major joints. Pathologists sectioned weight-bearing surfaces (such as femoral condyles and tibial plateaus) and graded them using the standardized Osteoarthritis Research Society International (OARSI) scheme. No evidence of joint-related risk, progressive cartilage lesions, or RPOA-like pathology was identified in any of the izenivetmab-treated groups.

Prepared by:

Jakub Knurek

Marketing Specialist

j.knurek@mabion.eu

Jakub Knurek

Marketing Specialist

Jakub Knurek is a marketing and business development expert specializing in CDMO operations with scientific and biopharmaceutical background. During the COVID-19 pandemic, he contributed to the development of the Novavax protein vaccine. As a side project, he runs his own pharma company.

As the author of numerous articles, he is recognized as an important voice of the younger generation of scientists. He is a member of Mabion’s representation at industry trade shows, including Central European BioForum 2026, Eurobiotech Congress 2026, BIO International Convention 2025 in Boston, 2nd Global Biologics India 2025 in Hydrabad, CPHI 2024 in Milan, CPHI 2023 in Barcelona, Life Sciences Baltics 2023 in Vilnius.

He actively participates in academic, business and industry discussions, such as the “Building the Future Pharma Workforce” panel at CPHI Milan 2024 or “Biotech in Translation: How to Tell the Story of Innovation” at Central European BioForum 2026.

Sources and further reading

1. Werts A, Saad K, Hummel B, Mangus L, Green E, Guillot M, Carlson C, Bedard A, Boyce R, Knauer CS, Roode S, Cole P. Laboratory safety evaluations of izenivetmab, a caninized anti-nerve growth factor monoclonal antibody, for three-month alleviation of osteoarthritic pain in dogs. Vet J. 2026; 317: 106635.
2. Fu Y, Guo Z, Wang H. Therapeutic Monoclonal Antibodies as Advanced Therapies for Companion Animals: Species Adaptation, Fc Biology, Clinical Translation, and Future Platforms. Vet. Sci. 2026; 13(8): 778.
3. Wang J, Zhou X, Elazab ST, Huang J, Hsu WH. Current Review of Monoclonal Antibody Therapeutics in Small Animal Medicine. Animals (Basel). 2025; 15(4): 472.