Sanofi and leading science-based biopharmaceutical company, Regeneron Pharmaceuticals, Inc. announced that pooled data from two phase 1b trials with dupilumab (REGN668/SAR231893), an investigational, high-affinity,  subcutaneously administered, fully-human antibody targeting the alpha subunit of the interleukin 4 receptor (IL-4R alpha), were presented at the 71st  Annual Meeting of the American Academy of  Dermatology (AAD) in Miami.

The primary objective of the phase 1b studies was to assess the safety profile of dupilumab. Other exploratory endpoints included pharmacokinetic, biomarker, and efficacy parameters. The efficacy data showed that treatment with four weekly subcutaneous injections of dupilumab at either 150 milligrams (mg) or 300mg per week, significantly improved the signs and symptoms of patients with moderate-to-severe atopic dermatitis (AD) whose disease was not adequately controlled with topical medications. Specifically, patients treated with dupilumab had significant improvements in body surface area (BSA) score, Investigator Global Assessment (IGA) score, and Eczema Area

Severity Index (EASI) from baseline to week 4  compared to placebo (p<0.05 vs. placebo for all measures and doses). The significant improvements in BSA, IGA, and EASI scores were maintained at week 8 in the 300mg dose group (p<0.05 vs. placebo). A responder analysis demonstrated that at week 4, 54.5% of patients treated with the 150mg dose and 71.4% of patients treated with the 300mg dose achieved a reduction in EASI score of 50% or greater compared to 18.8% with placebo (p<0.05). The most common adverse events (AEs) were nasopharyngitis (19.6% vs. 12.5% for placebo) and headache (11.8% vs. 6.3% for placebo).

“Despite existing therapies, a significant proportion of patients with moderate-to-severe atopic dermatitis continue to suffer from inflamed skin and intractable itch, which significantly impacts their quality of life,”  said Dr. Eric Simpson, Associate Professor, Director of Clinical Studies, Oregon Health and Science University, Portland, Oregon, USA, and Principal Investigator of the study. “The early phase results with this biologic therapy, which has a novel mechanism of action, are encouraging to those of us who treat these patients and warrant further clinical investigation.”

“Through blockade of the IL-4alpha receptor, dupilumab modulates signaling of both the IL-4 and IL-13 pathway, which have been implicated in the pathophysiology of allergic disease,” said George D Yancopoulos, M.D., Ph.D., Chief Scientific Officer of Regeneron and President of Regeneron Laboratories.  “We look forward to presenting additional data from a 12-week, Phase 2a trial in atopic dermatitis, as well as starting a larger Phase 2b trial with dupilumab in patients with atopic dermatitis, later this year.”

Presented in a late-breaking clinical trials session at the AAD meeting, the phase 1b trials included 67 patients randomized to three different doses of dupilumab (75mg, n=8; 150mg, n=22; 300mg, n=21) and placebo (n=16). The primary objective of the phase 1b studies was to assess the safety profile of dupilumab. Other endpoints included pharmacokinetic, biomarker, and efficacy    2/3 parameters. Following the 4-week treatment period, patients in the studies were followed for an additional 4 weeks for a total of 8 weeks.  

Atopic dermatitis and some types of asthma are characterized by the induction of a specific type of an immune response that is driven by a subset of immune cells called Type 2 helper T cells, or Th2 cells. IL-4 and IL-13 are key cytokines that are required for the initiation and maintenance of this Th2 immune response. Both IL-4 and IL-13 signaling occurs through two different IL-4 receptors (Type I and II), which both contain a common IL-4R alpha subunit.

Dupilumab is a fully human monoclonal antibody directed against IL-4Ralpha and is administered via subcutaneous injection. By blocking IL-4R alpha dupilumab modulates signaling of both IL-4 and  IL-13, drivers of a Th2 immune response. Dupilumab was created using Regeneron’s pioneering VelocImmune technology and is being co-developed with Sanofi. Dupilumab is currently being studied in both atopic dermatitis and asthma as a subcutaneous injection.
Atopic dermatitis (AD) is a chronic, immune-mediated, inflammation of the skin that is characterized by poorly defined erythema (redness) with edema (swelling), weeping in the acute stage, and skin thickening (lichenification) in the chronic stage. Chronic and/or relapsing lesions, along with pruritus (itching) and scratching are the hallmarks of the disease. The prevalence of AD is estimated to be between 1% and 3% of adults. For many patients, topical therapies are not effective for keeping the disease under control and the only approved systemic therapies to treat AD are prednisone and cyclosporine (in Europe). Moderate-to-severe atopic dermatitis can negatively impact patients’ lives and is associated with a high burden to society both in terms of direct costs of medical care and prescription drugs, as well as loss of productivity.