Trial Outcomes & Findings for Proof of Concept Study to Investigate Etokimab (ANB020) Activity in Adult Participants With Severe Eosinophilic Asthma (NCT NCT03469934)

This study was conducted at 6 centers in the United Kingdom (UK) and United States of America (USA).

Eligible participants were randomized in a 1:1 ratio to receive a single dose of either etokimab or placebo.

Proof of Concept Study to Investigate Etokimab (ANB020) Activity in Adult Participants With Severe Eosinophilic Asthma

An adverse event (AE) is any untoward medical occurrence in a participant or clinical investigation participant administered a pharmaceutical product and which does not necessarily have a causal relationship with this treatment. An AE was considered "serious" if there was any of the following outcomes: death, life-threatening, Inpatient hospitalization or prolongation of existing hospitalization, persistent or significant incapacity or substantial disruption of ability to conduct normal life functions, congenital anomaly/birth defect, other important medical events. Treatment-emergent adverse events (TEAEs) were defined as AEs that started or worsened in severity on or after the date and time of the study drug infusion.

Asthma exacerbation was defined as follows: 1. Use of systemic corticosteroids (or a temporary increase in a stable oral corticosteroid background dose) for at least 3 days; a single depo-injectable dose of corticosteroids was considered equivalent to a 3-day course of systemic corticosteroids. OR 2. An emergency room/urgent care visit (defined as evaluation and treatment for \<24 hours in an emergency department or urgent care center) due to asthma that required systemic corticosteroids (as per above). OR 3. An inpatient hospitalization (defined as admission to an inpatient facility and/or evaluation and treatment in a healthcare facility for ≥24 hours due to asthma).

FEV1 is the amount of air which can be forcibly exhaled from the lungs in the first second of a forced exhalation.

Measurement of FeNO was performed in accordance with the guidelines published by American Thoracic Society/European Respiratory Society (ATS/ERS).

Blood samples for ex vivo induced IFN-γ assessment were collected in a sodium heparin tube. The measurement of ex vivo induced IFN-γ was performed using validated assay method.

Cmax was obtained directly from the observed concentration versus time data.

Tmax was obtained directly from the observed concentration versus time data.

AUC0-inf was calculated by linear up/log down trapezoidal summation and extrapolated to infinity by addition of the last quantifiable concentration divided by the apparent terminal rate constant.

AUC0-last was calculated by linear up/log down trapezoidal summation.

CL was calculated as dose/ AUC0-inf.

λz was determined by linear regression of the terminal points of the log-linear concentration-time curve.

Apparent terminal half-life was determined as (natural logarithm of 2 \[ln2\] divided by λz).

Vz was estimated by dividing the systemic clearance by λz.

Volume of distribution at steady state following intravenous dosing was calculated as \[(\[AUMClast + (\[tlast\*Clast\]/λz) + Clast/λz\^2\]/ AUC(0-inf)) - TI/ 2\]\*CL, Clast is last observed (quantifiable) plasma concentration, where AUMClast is the area under the moment curve from the time of dosing to Clast, tlast is the time of Clast, and TI is infusion duration.