Aimmune Therapeutics Receives FDA Breakthrough Therapy Designation for AR101

BRISBANE, Calif.--Aimmune Therapeutics, Inc., a privately held biopharmaceutical company developing desensitization treatments for food allergies, announced today that the U.S. Food and Drug Administration (FDA) has granted Breakthrough Therapy Designation status to AR101, the company's lead investigational product, for oral immunotherapy of peanut-allergic children and adolescents 4-17 years of age.

Breakthrough Therapy Designation, an FDA program intended to facilitate and expedite development and review of new drugs and biologics for the treatment of a serious or life-threatening condition, requires preliminary clinical evidence that the drug may demonstrate substantial improvement over available therapies on one or more clinically significant endpoints. Under the program, the FDA will work closely with Aimmune Therapeutics on the subsequent development of AR101, including providing guidance on generating evidence needed to support approval of the drug in an efficient manner. AR101 also received FDA Fast Track Designation in September 2014, prior to Phase 2 clinical data.

"We are very grateful for the FDA's recognition of the large impact AR101 could have in reducing the incidence of life-threatening allergic reactions in people with peanut allergies," said Stephen Dilly, M.B.B.S., Ph.D., Chief Executive Officer of Aimmune Therapeutics. "Currently, there are no approved medical therapies to treat the more than two million children and adolescents in the United States and Europe with peanut allergy who are vulnerable to reactions from accidental exposures. We are eager to continue working closely with the FDA and to receive its guidance to help make AR101 available to patients as soon as possible."

Aimmune Therapeutics recently announced positive results of ARC001, its randomized, double-blind, placebo-controlled Phase 2 study of AR101 for desensitization treatment of peanut allergy. At the conclusion of the study, 100% of patients who completed the active treatment regimen (n=23) tolerated exposure to a cumulative amount of at least 443 mg of peanut protein, and 78% of those patients tolerated exposure to a cumulative amount of 1,043 mg of peanut protein. Dr. Wesley Burks presented the study results at the European Academy of Allergy and Clinical Immunology (EAACI) Congress 2015 in a late-breaking oral abstract session.

ARC001 treated 55 patients, with 29 in the active group (which had six early discontinuations due to gastrointestinal side effects and compliance issues) and 26 in the placebo group. Of the 55 patients, 54 were within a 4-17 age range. Aimmune Therapeutics plans to initiate a Phase 3 confirmatory registration trial of AR101 for the desensitization treatment of peanut allergy in children and adults.

About AR101 and CODIT™

Aimmune Therapeutics is developing AR101 as a potential desensitization therapy for patients with peanut allergy to provide them with protection from peanut allergens at a level believed to substantially exceed the amount typically encountered in an accidental exposure. AR101 is a complex mixture of naturally occurring proteins and pharmaceutical-grade inactive ingredients designed to enable the convenient dosing of consistent amounts of peanut protein with well-defined concentrations of peanut allergens. Patients ingest AR101 mixed with a common, age-appropriate food.

AR101 is part of Aimmune Therapeutics' approach to treating food allergies using its characterized oral desensitization immunotherapy, or CODIT™, system. The CODIT system leverages extensive independent scientific research on oral immunotherapy, or OIT, demonstrating that food allergy patients can be desensitized to exposure to food allergens by being administered well-defined, gradually increasing doses of the allergen over a period of months. Aimmune Therapeutics' CODIT system is designed to precisely control the amount of allergen administered and follow a systematic dosing regimen that begins with very low doses of the allergen. Once a patient attains desensitization to a clinically meaningful level of food allergen, the patient continues to take a daily maintenance dose of the CODIT system product in order to maintain such desensitization.

About Food Allergies

Food allergies are a significant and growing health problem in the United States, Europe and throughout the developed world. It is estimated that more than 30 million people in the United States and Europe have a food allergy, and more than five million people in the United States and Europe have peanut allergy, including more than two million children. The prevalence of peanut allergy in children in the United States is estimated to have increased at a constant annual growth rate of approximately 10% between 1997 and 2008, and experts believe it has continued to rise since 2008. For people living with food allergies, certain foods can cause severe allergic reactions, including potentially life-threatening anaphylaxis. There are no currently approved medical therapies to cure food allergies or prevent their effects. Currently, many food-allergic patients manage their condition by strict allergen avoidance and carrying epinephrine auto-injectors for use in case of accidental exposure. Thus, in addition to the unmet medical need, food allergies can impose a significant quality of life burden. For more information, please seewww.foodallergy.org and www.niaid.nih.gov/topics/foodallergy.

About Aimmune Therapeutics

Aimmune Therapeutics, Inc., founded in 2011 as Allergen Research Corporation (ARC), is a clinical-stage biopharmaceutical company developing treatments for peanut and other food allergies. Aimmune Therapeutics' characterized oral desensitization immunotherapy (CODIT™) system, an approach to oral immunotherapy (OIT), combines proprietary product candidates with gradual, controlled up-dosing protocols to obtain meaningful desensitization to food allergens. Aimmune Therapeutics recently completed a Phase 2 study of its lead product, AR101, a highly characterized, complex mixture of naturally occurring proteins and pharmaceutical-grade inactive ingredients for the treatment of peanut allergy, one of the most common food allergies. For more information, please see www.aimmune.com.