Half of all respiratory illness in cats can be attributed to feline rhinotracheitis, caused by the feline herpes virus (FHV). This upper respiratory or pulmonary infection, sometimes called feline influenza now has a serious foe: Polypreny Immunostimulant (PI). Taken by mouth, this drug can fight the blindness or even death that comes with cat rhinotracheitis.
Off label, it can also fight the dry form of feline infectious peritonitis (FIP). That’s where the big news is this story lies. No drug before PI offered even a glimpse of hope for cats diagnosed with FIP.
The USDA has issued a conditional license to Sass & Sass Inc. to distribute PI. PI is a plant-based immunostimulant that guides the immune system into the direction of cell mediated immunity. Cell mediated immunity is necessary for control of viral diseases in cats.
As he was studying the drug for its intended purpose to control symptoms of rhinotracheitis, Dr. Al Legendre, Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, began to study the same drug’s use in cats with FIP.
It turned out that PI unfortunately has no impact on the fatal course of wet (or effusive) FIP, but it seems to help prolong life and quality of life among at least some cats with the dry (non-effusive) form of FIP.
Sass & Sass and the Winn Feline Foundation Bria Fund (to support FIP research) quickly funded further studies.
In the first study, 58 cats with dry FIP received PI. Some cats died very soon or even before receiving their first treatment. Twenty two percent of the cats in the study were alive for least 165 days. Now, cats with dry FIP often wax and wane for several months (although six months is more than typical for most FIP diagnosed cats), however, Legendre noted their quality of life seemed “quite good” until near the end when the cats suddenly crashed.
No one suggests PI is a miracle drug for FIP, but it helps. Legendre says, “It appears that polyprenyl immunostimulant improves the survival times in cats with dry form FIP. It appears to improve well being of the cats and improves appetite. This is not the final answer to treatment of FIP but perhaps a step in the right direction. An antiviral treatment in conjunction with PI should improve clinical outcome.”
Dr. Tayna Kuritz, chief operating officer of Oak Ridge, TN-based Sass & Sass, which developed and manufactures PI adds, “We are committed to supporting FIP research, including by Dr. Legendre and through Bria Fund at Winn Feline Foundation. This disease [FIP] poses a major challenge; it is the most devastating of all feline diseases and is also found in ferrets. We need to develop a cure for it, and feline health research is critically and chronically underfunded.”
PI’s label will offer details on use for cats with rhinotracheitis. Veterinarians can now prescribe PI off-label as a treatment for cats with dry FIP. Veterinarians can contact Legendre for details on use for cats with dry FIP. Learn more about the drug through Sass & Sass.