An R&D collaboration between Dublin, Ireland-based Nexvet Biopharma, a veterinary biologics developer, and Japanese animal health company Zenoaqa claims to have found   fully caninized monoclonal antibodies (mAbs) that bind and potently inhibit the immuno-oncology target programmed cell death protein 1 (PD-1) in dogs.

The US Department of Agriculture Center for Veterinary Biologics has confirmed jurisdiction over the regulatory path for the program that allows conditional licensure, the market entry of a product on a comparatively rapid basis, under certain conditions, after a demonstration of purity, safety and a reasonable expectation of efficacy.

In the next step, the anti-PD-1 program will conduct further safety, pharmacokinetic and immunogenicity studies looking at candidate suitability and the design of any further studies required for regulatory approval.

Nexvet and Zenoaq are focused on PETizing mAbs identified by the latter company to create candidates in immuno-oncology and allergy/inflammation for companion animals.The two companies will share the development costs of their collaboration. Zenoaq will retain European and Asian marketing rights to any resulting products, with Nexvet retaining rights to the rest of the world, including North America.

Cancer therapeutics is an area where veterinary medicine has not benefited from the many major advances in human biologics development, the collaboration partners said, adding that cancer leads to significant morbidity and mortality in pet dogs, and the incidence will only increase as dogs live longer.

“Given the wealth of data generated in humans supporting the attractive safety profile and efficacy of PD-1 inhibitors against a variety of tumor types, we are excited to be advancing an anti-PD-1 antibody program for dogs with Zenoaq,” said Nexvet CEO Mark Heffernan.

As blocking the interactions of PD-1 and PD-L1 has resulted in approved therapies for humans with attractive safety profiles that demonstrate efficacy against multiple tumor types, the partners say they believe the clinical successes seen in human disease can be replicated in canine disease to produce effective therapies for multiple tumor types in dogs.

Successful cancer immunotherapies would be a new paradigm in veterinary oncology where current standards of care, including surgery, chemotherapy and radiotherapy, have exhibited significant treatment limitations, the companies noted.

Experts point out that dogs are susceptible to many of the same types of cancers that afflict people. Epidemiological studies are said to have shown that cancer is the leading cause of death in dogs over 10 years of age, with 50% of older dogs developing cancer and one in four dogs eventually dying from it.