ANB020 is an antibody that inhibits the activity of IL-33, a pro-inflammatory cytokine that multiple studies have indicated is a central mediator of atopic diseases, including atopic dermatitis, food allergies and asthma. IL-33 directly mediates release of disease-associated downstream cytokines, which recruit pro-inflammatory cells that mediate atopic disease. Because ANB020 inhibits IL-33 function, and acts upstream broadly across the key cell types and cytokines involved in atopy, we believe that its mechanism has advantages in the treatment of atopic diseases over competing agents that block only a subset of the downstream cytokines responsible for atopic diseases. The role of IL-33 signaling in asthma has been recently genetically validated through human studies published in the medical literature.
We have completed a Phase 1 trial of ANB020 in healthy volunteers in Australia. We believe the results of this Phase 1 trial demonstrate a favorable safety profile of ANB020, which was well-tolerated and for which no dose-limiting toxicities were observed, and favorable pharmacodynamic properties of ANB020, where a single dose was sufficient to suppress IL-33 function for approximately three months post-dosing as measured by an ex vivo pharmacodynamic assay. We presented these results at the 2017 American Academy of Dermatology Annual Meeting and the American Academy of Allergy, Asthma and Immunology 2017 Annual Meeting in March 2017.
We have subsequently completed enrollment of a Phase 2a trial where a single dose of ANB020 was administered to 12 moderate-to-severe adult atopic dermatitis patients, under an approved Clinical Trial Authorisation, or CTA, with the U.K. Medicines and Healthcare Products Regulatory Agency, or MHRA, and, announced top-line data from an interim analysis of this trial in October 2017. Top-line data indicated rapid and sustained achievement of EASI-50, which is 50% or better improvement in Eczema Area Severity Index (EASI) score relative to enrollment baseline, in 83% of patients at day 29, and reduced the 5-D pruritus score, which is a measure of itching, by 32% relative to enrollment baseline. As early as Day 15 post-ANB020 administration 75% of patients reached EASI-50 and pruritus was reduced by 28%, which was sustained until Day 57 when 75% of patients achieved EASI-50; pruritus was reduced by 22% at Day 57. No severe adverse events have been reported to date under this study. We believe these data demonstrate proof-of-concept for ANB020 in moderate-to-severe adult atopic dermatitis and provide meaningful differentiation in terms of patient convenience.
As further development in atopic dermatitis, we plan to initiate, during the first half of 2018, a Phase 2b randomized, double-blinded, placebo-controlled study in 200-300 adults patients with moderate-to-severe atopic dermatitis to evaluate multi-dose subcutaneous administration of ANB020.
We are continuing to enroll our on-going Phase 2a trial of ANB020 in the United States with 20 severe adult peanut allergy patients, where efficacy will be assessed by measuring the cumulative dose of peanut tolerated in an oral food challenge before and after a single dose of ANB020 or placebo, where we anticipate top-line data will be available during the first quarter of 2018. We are also enrolling a Phase 2a trial of ANB020 with 24 severe adult eosinophilic asthma patients, where efficacy will be assessed using improvement in Forced Expiratory Volume in One Second after administration of a single dose of ANB020 or placebo, where we anticipate top-line data during the second quarter of 2018.
Based on our analysis of publicly available data sources and interviews with physicians and key opinion leaders in the field of atopic dermatitis, we estimate approximately 1.4 million adults in the United States are affected by atopic dermatitis, of which approximately 280,000 are diagnosed with a moderate-to-severe form of this disease. Peanut allergy is the most common cause of food-induced allergy in the United States. Based on our analysis of publicly available data sources and interviews with physicians and key opinion leaders in the food allergy field, we estimate approximately 1.7 million adults are affected by peanut allergy, of which approximately 600,000 are treated by allergists and approximately 400,000 are at risk for severe reactions and therefore we believe are suitable for treatment with systemic biological therapies in the United States. We estimate, based on our analysis of publicly available data sources and interviews with physicians and key opinion leaders focused on asthma, that asthma affects approximately 19.0 million individuals, of which approximately 1.1 million have severe disease that cannot be controlled by standard-of-care therapy.
A translational research study, conducted by the laboratory of Dr. Erik Wambre at the Benaroya Research Institute in collaboration with AnaptysBio, assessed the biology of a distinct subset of T cells, called TH2A cells, which are found in elevated frequency in peanut allergic patients when compared to non-allergic individuals. TH2A cells isolated from peanut allergy patients demonstrated increased sensitivity to IL-33 signaling as a result of elevated expression of the IL-33 receptor. Data showed that, upon stimulus with IL-33, TH2A cells express significantly greater levels of effector cytokines IL-4, IL-5, and IL-13, which are believed to be associated with severe peanut allergy. The research concluded that IL-33 is a key checkpoint of allergic responses, and blocking IL-33 has the potential to reduce expression of the effector cytokines involved in severe peanut allergy. Data from this translational research study was presented at the American Academy of Allergy, Asthma and Immunology (AAAAI) 2017 Annual Meeting (click here to download).
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