P2043 - Similar Efficacy of Lirentelimab in Patients With New vs Prior Diagnoses of Eosinophilic Gastritis and/or Duodenitis in a Randomized Trial

Kathryn Peterson, MD, MSCI¹, Robert M. Genta, MD, FACG², Marc Rothenberg, MD, PhD³, Ikuo Hirano, MD⁴, NIrmala Gonsalves, MD⁴, Joseph A. Murray, MD⁵, Amol P. Kamboj, MD⁶, Bhupinder Singh, MD⁶, Henrik Rasmussen, MD, PhD⁶, Evan S. Dellon, MD, MPH, FACG^7
1University of Utah School of Medicine, Salt Lake City, UT; ²Inform Diagnostics, Irving, TX; ³Cincinnati Children’s Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH; ⁴Northwestern University Feinberg School of Medicine, Chicago, IL; ⁵Mayo Clinic, Rochester, MN; ⁶Allakos, Inc., Redwood City, CA; ⁷University of North Carolina School of Medicine, Chapel Hill, NC

Introduction: In ENIGMA, a phase 2 study of patients with eosinophilic gastritis and/or duodenitis (EG and/or EoD), lirentelimab significantly reduced symptom scores and depleted tissue eosinophils; 13/65 (20%) patients did not have prior diagnoses of EG and/or EoD (defined as ≥30 eosinophils/high-power field [hpf] in ≥5 hpfs in gastric biopsies and/or ≥3 hpfs in duodenal biopsies, respectively). We compared symptom responses of patients with new diagnoses (de novo patients) with those of patients with prior diagnoses of EG and/or EoD to lirentelimab in ENIGMA and an open-label extension (OLE) study.

Methods: Throughout ENIGMA and the OLE study, 8 symptoms (abdominal pain, nausea, vomiting, early satiety, loss of appetite, abdominal cramping, bloating, and diarrhea) were assessed using a daily electronic patient-reported outcome questionnaire; weekly total symptom scores (TSS) were generated. At week 14 of ENIGMA, TSS were available from 10 de novo patients (5 receiving placebo, 5 receiving lirentelimab) and 29 patients with prior diagnoses of EG and/or EoD (15 receiving placebo, 14 receiving lirentelimab). As of March 2021, in the OLE study, 18 patients with prior diagnoses of EG and/or EoD and 5 de novo patients had completed ≥94 weeks of lirentelimab (3.0 mg/kg). We compared changes in mean TSS from baseline and proportions of subjects with ≥50% improvement through week 94 of the OLE study.

Results: At the primary evaluation timepoint (week 14) of the ENIGMA study, de novo patients had TSS responses to placebo and treatment that were similar to those of patients with prior diagnoses of EG and/or EoD (Figure); 4/6 (67%) de novo patients receiving lirentelimab and 9/14 (64%) patients with prior diagnoses of EG and/or EoD had a ≥50% reduction in TSS, compared to 1/5 (20%) and 2/15 (13%) of the placebo patients, respectively. At week 94 of the OLE study, de novo patients had a mean 68% reduction in TSS and patients with prior diagnoses of EG and/or EoD had a mean 83% reduction in TSS; all 5 de novo patients (100%) and 16/18 (89%) patients with prior diagnoses of EG and/or EoD had a ≥50% reduction in TSS.

Discussion: In the screening phase of ENIGMA, we evaluated patients who had a prior diagnosis of EG and/or EoD and newly diagnosed (de novo) patients. Lirentelimab significantly reduced mean TSS from baseline in patients with prior or new diagnoses of EG and/or EoD, through 94 weeks; de novo patients had TSS responses to lirentelimab similar to those of patients with prior diagnoses of EG and/or EoD.



Disclosures:


Kathryn Peterson, MD, MSCI¹, Robert M. Genta, MD, FACG², Marc Rothenberg, MD, PhD³, Ikuo Hirano, MD⁴, NIrmala Gonsalves, MD⁴, Joseph A. Murray, MD⁵, Amol P. Kamboj, MD⁶, Bhupinder Singh, MD⁶, Henrik Rasmussen, MD, PhD⁶, Evan S. Dellon, MD, MPH, FACG⁷. P2043 - Similar Efficacy of Lirentelimab in Patients With New vs Prior Diagnoses of Eosinophilic Gastritis and/or Duodenitis in a Randomized Trial, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.