New Insights into Food Allergy Diagnosis and Therapy

Kari Nadeau, MD, PhD Director, Sean N. Parker Center for Allergy & Asthma Research at Stanford University Naddisy Family Foundation Professor of Medicine

Objectives

• Discuss new diagnostic methods for food allergy • Describe new possible experimental therapies in food allergy • Review new technologies that could aid in progress in the field of mechanistic studies • Nothing to disclose

What is food allergy?

Normal immune response is to protect the body from infection and disease Food allergy is an abnormal response to food PROTEIN IgE

Do You Have Food Allergies?

Food Allergies vs Food Intolerance

1/13 kids have food allergies In the U.S.

FOOD ALLERGY in numbers!!

•

#1 cause of anaphylaxis in the ER

•

Annual risk of a reaction is

>15%

Food allergy is an immune disease

Transit of food through the gut

Any disruption of oral immune tolerance => ALLERGY

Destruction of food proteins into components Immune tolerance to components

Critical Questions

What causes food allergy? Why is the prevalence on rise?

Exposure in utero Current Diet Gut Microbiota Detergents Hygiene

What is the route of initial exposure?

Pregnancy and Nuts

• 2000: Avoid eating peanuts, tree nuts during pregnancy American Academy of Pediatrics,

Pediatrics

, 2000 • 2008: Do not restrict maternal diet; no significant association between avoidance and protection from developing allergy Greer

et. al

.,

Pediatrics

, 2008 • 2014: Flip-flopping of recommendations for more than a decade Gupta,

JAMA Pediatrics

, 2014 • 2014: Very recent research shows decrease in the risk of developing nut allergies with peripregnancy nut intake Frazier et. al.,

JAMA Pediatrics

, 2014

VS

10 X more likely to have peanut allergy

Du Toit G, et al. JACI. 2008 Nov;122(5):984-91

Gold Standard Diagnostic: Food Challenge

How good are our Diagnostics?

Current diagnostics for food allergies

Skin Prick Test (SPT) Serum IgE titers & Component Resolved Diagnostics (CRD) Gold Standard Food Challenge Elimination diets

Variables that affect diagnostic outcomes

• Kinetics of allergic response vary among patients • Medications • Age of patient • Extract preparations • Sample collection • Health status (e.g. immune exacerbations) • Technique of skin prick test

Issues with SPT and IgE diagnostics:

• IgE levels fail to predict allergic responses – Indirect assessment – Only survey immediate and not late-phase responses • SPTs do not discriminate between a food sensitivity vs. a true allergy • Communication of IgE tests to patients can be confusing • Higher rates of false positives – Potential cross-reactivity between allergens

Caveats to current strategies for food allergy detection: SPT and IgE titers

Specific IgE Specificity: Cow’s milk 48% Hen’s egg 49% Wheat 43% Soy 38% Peanut Meta-analysis of published studies predicting accuracy of food allergy diagnostics European Food Allergy Guidelines, EAACI 2014 59%

Clinical History is part of accurate diagnosis Results of a Clinical Study of n=391 children undergoing 604 challenges

Perry, Wood, et al. JACI 2004

Component resolved diagnostics as an additional test to IgE and SPT

Caveats: standardization among reagents, cost, and interpretation

Nicolaou, et al. JACI 2011

Caveats to current strategies for food allergy detection: OFCs

• ~40% of OFC induced-anaphylaxis need epinephrine injections Noone, Ross, Sampson, Wang, et al. JACI In Practice 2015 • Generates anxiety for the patient • Variability among challenges • Requires a specialized setting with highly trained staff – Resource-intensive

There is an unmet need for better predicative diagnostics: encouraging diagnostics on the horizon

• Skin Testing with Microneedles with Peptides/Epitopes • Basophil activation test (BAT): Flow cytometric assay of peripheral blood basophils • Data mining for antibodies, T cell receptors and peptides • GWAS DNA methylation: Whole genome scan for methylated CpG motif in peripheral blood

Possible new methods to improve skin prick testing

• Skin prick testing has not advanced in about approximately 100 years • A new, quantitative skin prick test using epitopes-peptides to allergens that could possibly correlate with severity, using dissolvable microneedles.

• Quantitative blood flow imaging to measure responses Peanut microneedles Sun, Butte et al. Acta Biomaterialia 2013

DNA methylation signatures as possible biomarkers for food allergy

Genome-wide DNA Methylation Peripheral blood cells with objective OFCs N=58 food sensitized, Age 11-15 mo 50% reactive on OFC N=13 non allergic N=48 validation cohort Scored from 96 CpG sites FA status predictive with 79% accuracy even though T cell subset used

Martino, Allen, et al. JACI 2015

Basophil activation test (BAT) potentially predicts the degree of reaction severity Whole blood is sensitive to temperature fluctuations and anti-coagulant reagents (i.e. EDTA)

Santos, Lack et al. JACI 2014 Santos, Lack et al. JACI 2015

Comprehensive and Integrative Measur“Omics”: Possible diagnostic data from blood and the microbiome 14 Omics assays + Medical tests Billions of measurements

Other microbiomes: nasal, skin, tongue Chen, Nadeau, Snyder, et al. Cell 2012

Diagnosis over time in all ages: Longitudinal tracking 100 food allergic and control twins over periods of health, stress and other atopic diseases

Infection Year 1 Year 2 … Stress Diet change Nadeau and Snyder with Gupta and Wang research groups and others

Challenges to clinical trials and evaluations of therapeutic success

Oral Immunotherapy Study Design

as a possible method for allergy therapy

4-22 mo Provided by Dr. Wesley Burks of Duke University

Unmet need for comprehensive prognostics for allergy resolution

• What is allergy resolution?

– Need to distinguish between desensitization versus immune tolerance • Refractory responses or persistence of disease despite therapy: ‘daily allergic symptoms to less than 300mg of allergen for at least 3 months’ • Desensitization: allergic response upon re-challenge after a period of withdrawal post OIT • Immunological ‘tolerance’: no allergic reaction upon re-challenge after a period of withdrawal post OIT • Currently there is no commercially available test to assess allergy resolution in therapy trials

Correlating oral immunotherapy (OIT) with frequency of allergen-specific B cells

Use of Controls--health and allergic- is important

Hoh, Boyd, et al. JACI 2015

Peanut OIT modifies IgE and IgG

4

responses to major peanut allergens

Vickery, Jones, Burks, et al. JACI 2013

Epigenetic studies on peanut specific Treg show FOXP3 hypomethylation in “tolerant” subjects

Syed, Lyu, Galli, Nadeau, et al. JACI 2014

Determining prognosis based on multivariate analysis of allergen-specific T cells after OIT

Glanville, Ryan, Hovde, Galli, Nadeau, et al. 2015

Determining prognosis based on multivariate analysis of allergen-specific T cells after OIT

Glanville, Ryan, Hovde, Galli, Nadeau, et al. 2015

BACKGROUND to Adding Adjunct

Why add adjunctive therapy to Food Allergen IT?

Therapy to OIT

• There is no effective, regulatory agency-approved treatment for food allergy in the US, except to avoid the offending foods and to have ready access to self-injectable epinephrine. • Recently, oral desensitization has been used to treat patients with food allergy; the process is slow and associated with frequent allergic reactions.

• Rush IT with inhalant allergens using Omalizumab (ITN, Casale, et al.) Noone, Sampson, Wood, AAAAI 2014 Begin, et al. 2014 Nadeau, et al. 2011

Phase 2 randomized controlled trial with OIT + Omalizumab for Cow's Milk Allergy • • • • N=57 milk-allergic, 7-32 yrs, randomized to receive either blinded omalizumab or a placebo for 16 months.

Doses of milk oral immunotherapy began after four months of receiving either the omalizumab or the placebo. The results showed significant differences between the omalizumab vs. placebo groups regarding the • Number of oral immunotherapy dose-related symptoms per person • Number of reactions during dosing that required treatment • Need for epinephrine. In addition, significantly fewer escalation doses were needed before reaching the maintenance dose (3.84 g) in the omalizumab group. CONCLUSION: The next step is to examine whether omalizumab improves how quickly desensitization and tolerance are achieved.

Noone, Sampson, Wood, et al.

(AAAAI) 2014 Feb-Mar

Phase 1 multi center study using anti IgE with Cow’s Milk IT

with milk oral immunotherapy Baseline visit Start omalizumab (wk 0) Desensitization (1000 mg milk powder dose, 2000 mg cumulative) Weekly up dosing and continued omalizumab Maintain daily milk dose at home Off omalizumab Maintenance dose was 2000 mg * DBPCFC of 8 g Home daily milk ≥ 8 oz

*

Result:

9 of 11 patients with milk allergy treated with omalizumab and oral milk desensitization achieved the primary objective Week 0-9 Week 9 Week 9-16, escalation phase Week 16-24 Week 24-27 Week 24-52 Nadeau KC, Schneider LC, Hoyte L, Borras I, Umetsu DT. Children’s Hospital Boston and Stanford University J Allergy Clin Immunol. 2011 Jun http://www.ncbi.nlm.nih.gov/pubmed/21546071

CLINICAL PRELIMINARY RESULTS of Phase 1 studies at a

Summary

Single Site (Stanford University)

Median Age in yrs (range) Sex (% Male) Screening DBPCFC

Median (range)

Safety data Time at which 2000mg protein was reached

Median (range)

Initial high dose milk OIT (N=11) Initial low dose milk OIT (N=10) Control (N=10, food allergen avoidance) 8 (7-18) 9 (4- 26) 7 (5-16) 45% 60% 50% 25 mg (1.6-100 mg) 32.7 mg (6-183 mg) 1.8% of the total doses resulted in allergic reactions (0.10% severe) 2% of the total doses resulted in allergic reactions (0.13% severe) 21 mg (6-183 mg) No allergic reactions to food allergens; no accidental ingestions occurred 8 weeks (7-10 weeks) 56 weeks (42-71 weeks) No control participant reached 2000 mg without a reaction

Phase 1 Rush Multi Oral Immunotherapy (Rush mOIT) for multisensitized patients Screening Baseline visit - DBPCFC* - IgE measurement - Skin Prick Test Week 0 Omalizumab Rapid Desensitization 9 10 Desensitization Dose Escalation Visits (Dose increases dependent on patient and safety parameters) 11 12 13 14 16 23 Follow-up 24 48 Day 1: individual food allergens Day 2: (optional) multiple food allergens combined Up to 5 in 1:1:1:1:1 N=35 subjects (same eligiblity criteria as mOIT study) All subjects had DBPCFCs before entering All subjects had more than one food allergy confirmed on DBPCFC PRIMARY GOAL: SAFETY Approach: Rapid Begin, et al. 2014 2nd DBPCFC: individual food allergens

Safety Results: Phase 1 Rush Multi Oral Immunotherapy for multisensitized patients 1 0 6 3 2 5 4 7 0 2 1 7 4 3 6 5 1 1 2 2 3 3 4 4 5 5 Most common symptom: HIVES, Abdominal Pain Epi Use=.02% N=35 6 7

Months into OIT

6 7

Months into OIT

8 8 9 9 10

Rush mOIT

11

mOIT

Most common symptom: HIVES, Abdominal Pain Epi Use=.03% N=50 10 11 12 12 Begin, et al. 2014

Dosing Results of rush mOIT vs mOIT in Phase 1 Studies

Time to 300, 1000 and 4000 mg doses

3 months OIT 7 months OIT 9 months OIT Prior to Desensitization Baseline 12 months OIT 16 months OIT Negative Skin Tests

Rush Multi OIT: Blood & SPT Results for Peanut Baseline vs. Post-OIT Begin, et al. AACI 2014

Data from Rush mOIT show significant improvements in Quality of Life (QoL) (less allergies and asthma) 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% 58% 42%

6 mo

Black = Unchanged QoL score 29% 71%

12 mo ****

22%

18 mo

76% 5%

24 mo Blue = Improved QoL score

92% Arasi, et al. 2014, Otani, et al. 2013

Combination Markers: Computational approach to epitope survey, T cell Receptor, B Cell Receptor, antibodies

BAT Assays Glanville, Davis,

Nature Methods

et al.

2014 BAT www.distributedbio.com/abgenesis.html

Allergy Immunology Pathology The integrative, precision medicine-based science and collaborations fostered at the Center have created transformative change in preventing and predicting allergic disorders.

GI Dermatology Bioengineering Chemical Engineering Psychology/ Nutrition Medicine: Adult Pulmonary Immunity, Transplant, Infectious diseases Genetics Health Research and Policy/Statistics/ Informatics Otolaryngology

• • • • Our newly developed diagnostic and preventative protocols offer patients hope and promise Developed the first Rapid Multi Allergen Immunotherapy protocol, making Stanford the first to treat patients with multiple food allergies. Now in active Phase 2 and, with our oversight, in other centers across the globe. 14 unique, transformative clinical trials to date, including development of a new patented dietary supplement to prevent food allergies — Start as early as 3 months of age; 1 tablespoon of powder a day; easy to use and eat Quantified the Basophil Activation Test (BAT) using small volumes of blood, potentially predicting the degree of reaction severity First to apply epigenetics to determine if a patient has lost allergies and asthma

Our Center: addressing the need for catalytic change • • • • • • Catalyzing change and making impact in the world by focusing on patients and families Serving families 24/7 Getting closer to a cure for allergies and asthma by providing state of the art treatment and research Identifying causes of allergies and asthma Discovering and applying new ways to diagnose and prognose Collaborating through research and shared data across many different departments and institutions

Next steps: overcoming barriers to facilitate collaborations

 Sample size and study design • Multi-site approach, e.g. ITN network, European networks, Australia, FARE Centers of Excellence, NIAID CoFAR, Sean N. Parker Center • Community-based participation in clinical studies and in the development of tests  Comprehensive longitudinal studies • Data sharing and bioinformatics of large data sets – Normalization of complex and divergent data – Open source, secure, democratic and transparent decision making  Incorporating cutting edge science • Nanotechnology, microfluidics, high-dimensional immunophenotyping  Transparency and education with the food allergy community • Improved communication about diagnostics and outcomes  to the public, to patients, and their families

What is the biology behind food allergy?

•

We still need to understand the molecular and cellular underpinnings at blood and tissue levels

Conclusions • • • • Preliminary data from phase 1 studies designed to test safety therefore larger, randomized controlled blinded phase 2 studies are needed OIT is experimental and should be conducted by well-trained professionals Both initial low dose and initial high dose OIT (with Omalizumab) modulate the humoral specific response Immune mechanistic studies are important to coordinate with clinical studies

With Appreciation to Baylor, Patients and Families, Clinical and Laboratory Team and Collaborators