Mepolizumab for severe eosinophilic asthma: a comparison of efficacy in children, adolescents, and adults

Background Mepolizumab is approved for severe eosinophilic asthma in adults and, in some regions, adolescents (12 – 17 years old). Efficacy results in children (6 – 11 years old) have yet to be compared to data from adults and adolescents.

Methods Asthma exacerbation incidence and asthma control questionnaire (ACQ-5) responder rates were taken from adult/adolescents in double-blind, placebo controlled studies (NCT01000506, NCT01691521, NCT02281318, NCT01691508) of mepolizumab 75 mg to 750 mg while children (40 mg SC if < 40 kg, 100 mg SC if ≥ 40 kg) were assessed in one open-label, uncontrolled study (NCT02377427). Comparisons after 12 weeks of treatment were considered post-hoc.

Results Subjects had similar mean exacerbation rates in the year prior to study: 4.0 in children and 2.8 – 3.6 in adolescents/adults. All subjects reported at least 2 exacerbations in the prior year. The incidence of exacerbations after 12 weeks of mepolizumab treatment was consistent between children and adolescents/adults (Table). The ACQ-5 responder rate (minimal clinically important reduction ≥ 0.5 points) at 12 weeks was 55% in children, 33 – 63% in adolescents, and 52 – 56% in adults.

Conclusions Mepolizumab in children with severe eosinophilic asthma results in similar efficacy (exacerbations and ACQ-5) when compared to adolescents/adults after 12 weeks.

Funding GSK

Tab. 1 Exacerbation Incidence After 12 Weeks of Treatment

	Children	Adults/Adolescents
	200 363	MEA112997	MEA115588	200 862	MEA115575
1  A range of Kaplan Meier estimates provided where > 1 mepolizumab dose studied
Placebo	Not available	39.2%	38.2%	27.9%	44.2%
Mepolizumab1	27.8%	14.9% −22.7%	19.9% −25.0%	12.2%	30.0%

Abstract previously presented at ERS 2018 (#PA5447).