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'Bringing Cats And Their Allergic Owners Closer'

Published: 6/24/2019

A Feline-Friendly Breakthrough In Cat Allergen Reduction Allergies to cats are the most common animal-origin allergies in humans,1 and affect approximately 1 in 5 adults worldwide.2   

A common problem with consequences for humans and cats
Allergies can impair quality of life for allergy sufferers by interfering with daily activities and performance.3,4 They also limit the interactions between the allergic person and their cat, and allergy to cats is a commonly provided reason for relinquishment to shelters5-9 as well as a barrier to cat adoption and ownership.9-10
Fel d1, the major cat allergen
Fel d1 is the major cat allergen.4,11-13 All cats produce Fel d1 regardless of breed or physical characteristics; there are no truly allergen-free or hypoallergenic cats.11,14-19 It is produced primarily in the salivary and sebaceous glands, spread throughout the cat’s hair coat during grooming, and shed into the environment with hair and dander.11,15 Fel d1’s function for the cat is as yet unknown, but a pheromone/chemical signaling role has been proposed.11,12,20
Reducing allergen exposure is key to allergy management
Avoiding exposure to the allergen is the foundation for allergists’ recommendations to remove the cat from the home.4,17,18 Stringent environmental controls (such as excluding the cat from the bedroom; removing carpeting; and regular, thorough cleaning) can successfully reduce Fel d1 levels, possibly allowing the cat to remain in the home,4,18,21 but these measures are effort-intensive and may be difficult to maintain long-term.


A transformational approach for allergies to cats
For the first time in history, Purina scientists have demonstrated a proactive way to significantly reduce the active levels of Fel d1 by taking advantage of the antibody-allergen interaction to neutralize Fel d1 after its production by the cat, but before it is spread into the environment. Anti-Fel d1 IgY antibodies bind and neutralize Fel d1, preventing it from binding to IgE in a Fel d1-sensitized individual.
Purina’s research showed when cats were fed a diet with an egg product ingredient containing anti-Fel d1 IgY, 97% showed decreased levels of active Fel d1 on their hair and dander. (“Active” Fel d1 is Fel d1 that is capable of binding to IgE and triggering an allergic response in sensitized individuals).22 On average, there was a 47% reduction of active Fel d1 on cats’ hair after 3 weeks of feeding the diet.23 Additionally, 86% of cats had a reduction of at least 30% from baseline levels.23  
This ultimately reduces active Fel d1 levels in the environment. Cat-allergic people exposed to dander from cats fed a diet with anti-Fel d1 IgY showed significant reductions in nasal allergy symptoms and some ocular symptoms.24
The ingredient is safe for cats, based on a comprehensive safety study that fed an egg product ingredient with multiple levels of anti-Fel d1 IgY, including levels many times higher than those used in our studies.25
Change the conversation. Keep the cat.
Cat owners with allergies to cats face a difficult conversation with an allergist or veterinarian who might recommend rehoming the cat. Because of Purina’s transformational approach to managing these allergies, now they can have a different conversation — one that helps keep cats in loving homes.
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  22. Satyaraj, E., Li, Q., Sun, P. & Sherrill, S. (2019). Anti-Fel d1 immunoglobulin Y antibody-containing egg ingredient lowers allergen levels in cat saliva. Accepted for publication, Journal of Feline Medicine and Surgery.
  23. Satyaraj, E., Gardner, C., Filipi, I., Cramer, K. & Sherrill, S. (2019). Reduction of active Fel d1 from cats using an antiFel d1 egg IgY antibody. Immunity, Inflammation & Disease. Advanced online publication. doi:10.1002/iid3.244
  24. Wedner, J., Satyaraj, E., Gardner, C., Al-Hammadi, N., Sherrill, S. & Mantia, T. (2019, June) Pilot study to determine effect of feeding cat food made with egg product containing anti-Fel d1 antibodies to cats on human allergy symptoms. Presented at the annual meeting of the European Academy of Allergy and Clinical Immunology, Lisbon, Portugal.
  25. Matulka, R. A., Thompson, L. & Corley, D. (2019). Evaluation of a multi-level safety study of anti-Fel d1 IgY. Submitted, Journal of Food and Chemical Toxicology.