Study to Investigate Etokimab (ANB020) Activity in Adult Participants With Peanut Allergy

Placebo-Controlled Proof of Concept Study to Investigate ANB020 Activity in Adult Patients With Peanut Allergy

The purpose of this study is to determine etokimab safety, tolerability and activity in adult participants with peanut allergy.

This is a multi-center, randomized, double-blind, placebo-controlled, proof of concept study to assess the safety and tolerability of etokimab in adult participants with peanut allergy.

Participants received a single dose of 300 milligrams (mg) etokimab administered by 1-hour intravenous (IV) infusion on Day 1.

An adverse event (AE) is any untoward medical occurrence in a patient or clinical investigation patient administered a pharmaceutical product and which does not necessarily have a causal relationship with this treatment. AEs include any clinical laboratory test results determined to be clinically significant by the investigator. AE was considered "serious" if there was any of the following outcomes: death, life-threatening AE, inpatient hospitalization or prolongation of existing hospitalization, persistent or significant incapacity or substantial disruption of the ability to conduct normal life functions, congenital anomaly/birth defect, other important medical events. Each AE was evaluated for severity (mild, moderate, or severe) and causal relationship to the study drug. AE was considered TEAE if the date of onset was during or after first dose of study treatment, or if the AE present at baseline worsened in either intensity or frequency after first dose of study treatment.

Oral food challenges were performed at Baseline and Day 14 in accordance with the Practical Allergy (PRACTALL) consensus report. Escalating doses of peanut protein (peanut flour mixed with a non-allergic food vehicle such as apple sauce) consisting of 5, 20, 50, 100, 100, 100, and 125 mg (for a cumulative maximum dose of 500 mg) were given at 20 minute intervals. If the participant developed any signs of an objective allergic reaction, the challenge was stopped. The total cumulative tolerated dose of blinded peanut reached prior to reaction was recorded.

Oral food challenges were performed at Baseline and Day 14 in accordance with the PRACTALL consensus report. During OFC the OFC Symptom Scoring Assessment Tool was used to assess participants for common symptoms that can be suspected to be an allergic reaction involving the skin, upper respiratory, lower respiratory, gastrointestinal, and cardiovascular systems. Each symptom was scored according to the following scale: Grade 0 = sign or symptom not observed; Grade 1 = mild; Grade 2 = moderate, Grade 3 = severe. The score from each symptom was averaged to calculate the overall score at Baseline and on Day 14.

The concentration of etokimab was measured using a validated assay method. The lower limit of quantification (LLOQ) was 0.400 microgram per milliliter (μg/mL).

Day 1 predose, 0.5 hours after the start of the infusion, end of infusion (EOI), 3 hours after EOI, 24, 96, 336 (Day 15), and 1056 (Day 45) hours after the start of infusion.

The concentration of etokimab was measured using a validated assay method. The lower limit of quantification (LLOQ) was 0.400 μg/mL.

Day 1 predose, 0.5 hours after the start of the infusion, EOI, 3 hours after EOI, 24, 96, 336 (Day 15), and 1056 (Day 45) hours after the start of infusion.

Area Under the Concentration-time Curve in Serum From Time Zero Extrapolated to Infinite Time (AUC0-inf) for Etokimab

Area under the concentration-time curve in serum from time zero (predose) extrapolated to infinite time, calculated by linear up/log down trapezoidal summation and extrapolated to infinity by addition of the last quantifiable concentration (Clast) divided by the apparent terminal rate constant (λz): AUC(0-last) + Clast/λz.

Day 1 predose, 0.5 hours after the start of the infusion, EOI, 3 hours after EOI, 24, 96, 336 (Day 15), and 1056 (Day 45) hours after the start of infusion.

Area Under the Concentration-time Curve in Serum From Time Zero to the Time of the Last Quantifiable Concentration (AUC0-last) for Etokimb

Area under the serum concentration-time curve from time zero to the time of the last quantifiable concentration, calculated by linear up/log down trapezoidal summation.

Day 1 predose, 0.5 hours after the start of the infusion, EOI, 3 hours after EOI, 24, 96, 336 (Day 15), and 1056 (Day 45) hours after the start of infusion.

Day 1 predose, 0.5 hours after the start of the infusion, EOI, 3 hours after EOI, 24, 96, 336 (Day 15), and 1056 (Day 45) hours after the start of infusion.

Day 1 predose, 0.5 hours after the start of the infusion, EOI, 3 hours after EOI, 24, 96, 336 (Day 15), and 1056 (Day 45) hours after the start of infusion.

Volume of distribution at steady state following intravenous dosing, calculated as mean residence time (extrapolated to infinity) multiplied by systemic clearance.

Day 1 predose, 0.5 hours after the start of the infusion, EOI, 3 hours after EOI, 24, 96, 336 (Day 15), and 1056 (Day 45) hours after the start of infusion.

Volume of distribution is defined as the theoretical volume in which the total amount of drug would need to be uniformly distributed to produce the desired plasma concentration of a drug. Volume of distribution was estimated by dividing the systemic clearance by apparent terminal rate constant (λz).

Day 1 predose, 0.5 hours after the start of the infusion, EOI, 3 hours after EOI, 24, 96, 336 (Day 15), and 1056 (Day 45) hours after the start of infusion.

The terminal elimination rate constant (λz) is defined as the first-order rate constant describing the rate of decrease of drug concentration in the terminal phase. Apparent terminal rate constant was determined by linear regression of the terminal points of the log-linear concentration-time curve.

Day 1 predose, 0.5 hours after the start of the infusion, EOI, 3 hours after EOI, 24, 96, 336 (Day 15), and 1056 (Day 45) hours after the start of infusion.

Inclusion Criteria: Male and female participants with age > 18 years and able to give informed consent. Participants with a confirmed clinically allergic response to peanut. Positive clinical reaction during the peanut oral food challenge and no clinical reaction during the placebo challenge Positive peanut allergy skin prick test > 3 millimeters (mm) of the negative control and detectable serum peanut-specific Immunoglobulin E (IgE) levels by ImmunoCAP testing. Body mass index (BMI) of 18 to 36 kilogram per square meter (kg/m^2) inclusive) and total body weight > 50 kg (110 lb). BMI = weight (kg)/(height [m^2]). Willing and able to comply with the study protocol requirements. Have the ability to read and understand the study procedures and have the ability to communicate meaningfully with the Investigator and staff. Women of childbearing potential, must have a negative serum pregnancy test at screening and Day 1, and be surgically sterile or using an acceptable method of contraception throughout the study and for 15 weeks after the last administration of investigational product. Postmenopausal participants defined as (1) aged over 45 years with at least 1 year of amenorrhea and levels of follicle stimulating hormone over 20 international units per liter (IU/L) or (2) aged over 50 years with at least 1 year of amenorrhea. Male participants must be willing to use effective methods of contraception during the entire study period and for 15 weeks after the last administration of investigational product. Exclusion Criteria: Have concomitant dermatological or medical condition(s) which may interfere with the Investigator's ability to evaluate the participant's response to the investigational product. Have experienced severe life-threatening anaphylactic reactions to peanuts within 6 months before screening (i.e., requiring an intensive care unit [ICU] admission). Positive clinical reaction observed during the placebo oral food challenge. Participation in any interventional study for the treatment of peanut and/or food allergies in the 12 months before screening. Have received any investigational product or been part of any interventional clinical study within a period of 3 months or 5 half-lives (whichever is longer) before screening. Have received systemic corticosteroids, nonsteroidal, immunosuppressant, or immunomodulating drugs treatments within 2 weeks before screening. Use of beta blockers, angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, or calcium channel blockers within 2 weeks before screening. History of ischemic cardiovascular diseases. Use of biologics within 6 months before screening or participant is in build-up phase of allergen immunotherapy (excluding peanut) and has not reached maintenance dose. Have received antibiotic treatment within 1 week before screening. Have a history of hypersensitivity or allergic reactions following infusions of human blood or blood components. Have a history of hypersensitivity or allergic reactions a component of etokimab formulation or the inactive ingredients (excipients). If female, are pregnant or lactating, or intend to become pregnant during the study period. Current diagnosis of asthma requiring Global Initiative for Asthma Assessment (GINA) Step 4 or higher treatment or asthma partially controlled or uncontrolled according to GINA classifications in the last three months before screening. History of a life threatening asthma attack within 1 year before screening (example: requiring an intensive care unit admission, intubation with mechanical ventilation). Other significant medical conditions that in the opinion of the Principal Investigator, prevent participation in the study. History of drug, alcohol or other substance abuse, or other factors limiting the ability to cooperate and to comply with the study protocol. Have any other physical, mental, or medical conditions which, in the opinion of the Investigator, make study participation inadvisable or could confound study assessments. Receipt of a live attenuated vaccine within 4 weeks before screening. Planned surgery during the study or 30 days before screening.

Chinthrajah S, Cao S, Liu C, Lyu SC, Sindher SB, Long A, Sampath V, Petroni D, Londei M, Nadeau KC. Phase 2a randomized, placebo-controlled study of anti-IL-33 in peanut allergy. JCI Insight. 2019 Nov 14;4(22):e131347. doi: 10.1172/jci.insight.131347.