ES Dellon et al. NEJM 2020; 383: 1624-1634. Anti–Siglec-8 Antibody for Eosinophilic Gastritis and Duodenitis
Background: AK002 (lirentelimab) is an anti-Siglec-8 antibody that depletes eosinophils and inhibits mast cells.
Methods: In this phase 2 trial, the authors randomly assigned adults (n=65) who had symptomatic eosinophilic gastritis, eosinophilic duodenitis, or both conditions in a 1:1:1 ratio to receive four monthly infusions of low-dose AK002, high-dose AK002, or placebo
Key findings:
- The mean percentage change in gastrointestinal eosinophil count was −86% in the combined AK002 group, as compared with 9% in the placebo group
- Treatment response (>30% reduction in total symptom score and >75% reduction in gastrointestinal eosinophil count) occurred in 63% of the patients who received AK002 and in 5% of the patients who received placebo
- The authors note that AK002 “also resulted in alleviation of dysphagia in patients with a history of concomitant eosinophilic esophagitis.”
- Limitations: Small study and 10% developed antibodies to drug
My take: Larger phase 3 studies with AK002 are underway (NCT04322604 & NCT04322708). AK002 looks promising for eosinophilic gastrointestinal diseases.

Related blog posts:
- Epidemiology of eosinophilic diseases
- How many eosinophils indicate eosinophilic gastroenteritis or colitis?
- Anti-TNF Therapy for Eosinophilic Gastroenteritis
- Eosinophiliic Esophagitis NEJM Review -post also includes information on eosinophilic gastritis