SAN ANTONIO — A novel therapeutic agent helped reduce eosinophil counts and improve symptoms in patients with eosinophilic gastritis and eosinophilic gastroenteritis, according to study results presented at the American College of Gastroenterology Annual Meeting.
The drug, AK002 (Allakos), is an anti-siglec-8 antibody that depletes eosinophils and inhibits mast cell activity.
“This mechanism of action suggests it could be an effective treatment for [eosinophilic gastrointestinal disorders],” Evan S. Dellon, MD, MPH, FACG, director of the Center for Esophageal Diseases and Swallowing at the University of North Carolina School of Medicine, said in his presentation. “The aim of this phase 2 study was to determine the safety and efficacy of AK002 for treatment of eosinophilic gastritis and eosinophilic gastroenteritis.”
The study, known as the ENIGMA trial, comprised 59 patients with biopsy-confirmed eosinophilic gastritis (EG) or eosinophilic gastroenteritis (EGE) with moderate to severe symptoms. Researchers randomly assigned patients to receive low-dose or high-dose AK002 or placebo.
The primary endpoint of the study was mean percent change in GI tissue eosinophil count from baseline. Investigators also assessed the proportion of patients with both a greater than 75% decrease in tissue eosinophils and a greater than 30% improvement in total symptom score, as well as mean percent change in total symptom score from baseline.
Patients in both AK002 groups had an overall mean reduction in eosinophils from baseline of 95% compared with just 10% in the placebo group (P < .0001).
Compared with placebo, patients who received the drug also saw better improvement in symptom scores (P = .0012) and more were treatment responders (69% vs. 5%; P = .0008).
Researchers found that treatment emergent adverse events were similar between the two groups, and the most common adverse events in the treatment group were mild-to-moderate infusion-related reactions at the first infusion only.
Dellon said AK002 demonstrated significant histologic and symptomatic improvement in patients with EG and EGE.
“These results build on the clinical activity of AK002 observed in other atopic and mast cell disorders ... and indicate that further development of AK002 for EG and EGE is appropriate,” Dellon said. – by Alex Young
Dellon ES, et al. Abstract 36. Presented at: American College of Gastroenterology Annual Meeting; Oct. 25-30, 2019; San Antonio.
Disclosures: Dellon reports serving on the advisory board for and receiving grant/research support from Allakos.