Regeneron’s antibody duos significantly lowered eye itching and redness, as well as pin prick reactivity, in people with cat and birch allergies. Still, BMO Capital Markets expressed uncertainty about the assets’ “commercial potential in a highly generic market.”
Regeneron’s investigational allergen-blocking antibodies have successfully eased symptoms in two separate late-stage studies of cat and birch pollen allergies.
Writing to investors on Monday, analysts at BMO Capital Markets said Regeneron’s “antibody cocktails” resulted in “robust reductions” in various allergy symptoms, including eye itchiness and redness. BMO is “broadly impressed by the strength” of Regeneron’s findings, though the firm remains uncertain about the assets’ “commercial potential in a highly generic market.”
In the cat study, Regeneron tested a combination of two antibodies—REGN1908 and REGN1909—designed to target the most dominant cat allergen, a molecule called FeID1. Results showed that ocular itch was cut by 52% versus placebo, assessed one week after treatment.
REGN1908 and REGN1909 likewise significantly eased conjunctival redness and skin prick reactivity, with respective effect sizes of 39% and 44%. The antibody combo had stronger efficacy in study participants whose allergies were first confirmed to have been driven by FeID1, resulting in a 65% drop in ocular itching.
Similarly, Regeneron tested two other antibodies, REGN5713 and REGN5715, designed to target BetV1, the dominant allergenic birch pollen protein. Results likewise demonstrated “impressive” symptom reduction, according to BMO, with a 51% decrease in eye itching. Conjunctival redness and skin prick reactivity dropped by 46% and 44%, respectively.
In both studies, Regeneron’s antibody cocktails were safe and well-tolerated, with no dropouts linked to serious treatment-related adverse events. The pharma expects to launch additional late-stage trials later this year for birch allergy and in the first half of 2026 for cat allergy.
Despite these two late-stage wins, BMO raised questions regarding the market prospects of Regeneron’s antibodies. “Commercialization story remains uncertain,” the analysts wrote. “While we do not discount the number of sufferers of allergies, we need to hear more about a potential commercial strategy for Regeneron to penetrate this market, which is heavily dominated by generics like antihistamines.”
Elsewhere in the allergy space, ARS Pharmaceuticals in March won the FDA’s go-ahead for the nasal-spray version of its epinephrine drug neffy, indicated for type I allergic reactions, including anaphylaxis, in children. The approval opened up the use of neffy 1-mg to kids 4 years and older who weigh from 15 kg to less than 30 kg.
