One shot may provide months of protection

Medial scientists may have come up with the answer for one of romance’s biggest conundrums: Fluffy, or the boyfriend who is allergic to cat dander?

Eight days following a single dose of the experimental agent REGN1908-1909 – an anti-feline dander 1 agent – early asthmatic response was reduced by 64% compared to individuals given a placebo, and the effect was maintained for as long as four months, reported Frederic de Blay, MD, professor of pulmonology at University Hospital of Strasbourg, France.

The proof-of-concept study, performed in a controlled environment, attempted to see if one dose of REGN1908-1909 would benefit mildly asthmatic patients who were allergic to cats but did not live with a cat when they were challenged with cat allergen. The measure of success was time to early asthmatic response as measured by lung function (FEVB1). The challenges were placebo controlled, de Blay and colleagues reported at the virtual meeting of the American Academy of Allergy, Asthma & and Immunology.

Regarding that primary endpoint, the researchers reported that “Single-dose REGN1908-1909 600 mg subcutaneously results in rapid and durable effect versus placebo.” The early asthmatic response occurred in about 52 minutes among participants in the study who were given placebo injections, but the median time to an early asthmatic response had not occurred within four hours (P=0.0083) among the individuals who were given the active therapy, Dr. de Blay reports.

Skin tests showed decreased response to cat allergen at 4 months, Dr. de Blay reports.

“The results are promising for this novel treatment designed to target the underlying cause of cat allergies and provide patients with passive immunity,” said Jennifer Maloney, MD, Executive Director of Strategic Program Direction at Regeneron. “Using an environment exposure unit, you can simulate significant cat exposure. What we need to do in future studies is actually test the drugs more in a real-life situation where people are living with the cat.”

In commenting on the study, Punita Ponda, MD, assistant chief, allergy and immunology, Northwell Health; Assistant Professor, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Great Neck, New York; and investigator working on other immunology/allergy trials at Regeneron. “The study is well designed and provides convincing data that REGN1908-1909 could be clinically beneficial in the treatment of cat triggered asthma.

“It would be beneficial for the cat lover who has asthma, which may be difficult to control, but avoiding cats is not an option,” she says. “The patient, of course, would benefit, but their loved ones who may be the reason the cat is in the house, will of course be cheering on the progress on this treatment. I guess, then, this would be great for all cat lovers. The doctors who take care of patients with asthma triggered by cat are also going to be watching for progress of this treatment.”

About 43% of all households in the United States have pet cats, according to the American Pet Products Association’s 2019-202 National Pet Owners Survey. “Cat allergen is very hearty and is considered a ubiquitous allergen indoors,” says Dr. Ponda. “The allergen seems to stay around sometimes for many weeks or months after a cat has gone from an indoor environment. Thus, for patients with asthma, who are cat allergic and have cat exposure, this can be particularly potent. We have allergy shots that can help the patient become less sensitive or not sensitive to cat, but if this new product works, it can be another option.

“More needs to be studied before we are fully convinced, though,” she adds. “Questions remain if this treatment will need to be repeated every few months to sustain response, since cat is not a seasonal allergen but present all year in the house. We also need to find out more about the response to real life cat exposure when it is beyond the 8-day mark after the shot. Thus, details will need to be worked out, but this is a very promising start to a possible new treatment option for cat allergy.”

For the study, Dr. de Blay and colleagues screened 130 mildly asthmatic individuals who complained of cat allergy, and found that 90 of them exhibited allergic reactions to cat allergen. They further determined in the screening part of the study that 56 participants had a early asthmatic response — within two hours — to cat allergen and were randomly assigned to receive REGN1908-1909 and one-shot of placebo.

The mean age of the 27 people who received the active agent was 28.4 years; the mean age of the placebo group was 30.2 years. About 37.5% of the group were men. About 96% of the participants were non-Hispanic or Latino.

  1. For people with mild asthma who are allergic to cat allergen, the new agent may be helpful in allowing these people to live with their cat.
  2. Be aware this was an early phase, laboratory-controlled study, presented at a meeting. Further study and peer-review are necessary to adequately interpret these findings.

Edward Susman, Contributing Writer, BreakingMED™

De Blay has disclosed relationships with ALK-Abelló, Novartis, Boehringer, Stallergenes, Meda Pharma, AstraZeneca, GlaxoSmithKline, Regeneron and MSD.

Ponda disclosed that she is an investigator at Regeneron, working on other immunology/allergy trials, but not cat allergy.