A Study of Lirentelimab (AK002) in Patients With Active Eosinophilic Esophagitis (KRYPTOS)

A Phase 2/3, Multicenter, Randomized, Double-Blind, Placebo-Controlled Study to Evaluate the Efficacy and Safety of Lirentelimab (AK002) in Adult and Adolescent Patients With Active Eosinophilic Esophagitis

This is a Phase 2/3, multi-center, randomized, double-blind, placebo-controlled study to assess the efficacy and safety of lirentelimab (AK002) given monthly for 6 doses in adult and adolescent patients with active eosinophilic esophagitis. Subjects who complete the randomized, double-blind, placebo-controlled treatment may have the option to receive 6 doses of open-label lirentelimab (AK002) through the OLE Period of the study.

Study Overview

• Status: Completed
• Conditions: Eosinophilic Esophagitis
• Intervention / Treatment: Other: Placebo; Drug: lirentelimab (AK002)

• Study Type: Interventional
• Enrollment (Actual): 277
• Phase: Phase 2; Phase 3

Contacts and Locations

Study Locations

• Australia
  • South Australia
    • Adelaide, South Australia, Australia, 5000
      • Allakos Investigational Site
    • Elizabeth Vale, South Australia, Australia, 5112
      • Allakos Investigational Site
  • Victoria
    • Box Hill, Victoria, Australia, 3128
      • Allakos Investigational Site
    • Prahran, Victoria, Australia, 3181
      • Allakos Investigational Site
• Netherlands
  • North Holland
    • Amsterdam, North Holland, Netherlands, 1105 AZ
      • Allakos Investigational Site
• United States
  • Alabama
    • Birmingham, Alabama, United States, 35209
      • Allakos Investigational Site
    • Huntsville, Alabama, United States, 38801
      • Allakos Investigational Site
  • Arizona
    • Gilbert, Arizona, United States, 85234
      • Allakos Investigational Site
    • Phoenix, Arizona, United States, 85016
      • Allakos Investigational Site
    • Phoenix, Arizona, United States, 85021
      • Allakos Investigational Site
    • Scottsdale, Arizona, United States, 85251
      • Allakos Investigational Site
  • Arkansas
    • Little Rock, Arkansas, United States, 72205
      • Allakos Investigational Site
  • California
    • La Jolla, California, United States, 92037
      • Allakos Investigational Site
    • Los Angeles, California, United States, 90025
      • Allakos Investigational Site
    • Oakland, California, United States, 94612
      • Allakos Investigational Site
    • Santa Monica, California, United States, 90404
      • Allakos Investigational Site
    • Tustin, California, United States, 92780
      • Allakos Investigational Site
    • Ventura, California, United States, 93003
      • Allakos Investigational Site
    • Walnut Creek, California, United States, 94598
      • Allakos Investigational Site
  • Colorado
    • Aurora, Colorado, United States, 80045
      • Allakos Investigational Site
    • Centennial, Colorado, United States, 80112
      • Allakos Investigational Site
  • Florida
    • Brandon, Florida, United States, 33511
      • Allakos Investigational Site
    • Edgewater, Florida, United States, 32132
      • Allakos Investigational Site
    • Jacksonville, Florida, United States, 32256
      • Allakos Investigational Site
    • Miami, Florida, United States, 33176
      • Allakos Investigational Site
    • Orlando, Florida, United States, 32803
      • Allakos Investigational Site
    • Orlando, Florida, United States, 32806
      • Allakos Investigational Site
    • Tampa, Florida, United States, 33603
      • Allakos Investigational Site
    • Tampa, Florida, United States, 33615
      • Allakos Investigational Site
  • Georgia
    • Atlanta, Georgia, United States, 30342
      • Allakos Investigational Site
    • Columbus, Georgia, United States, 31904
      • Allakos Investigational Site
  • Illinois
    • Chicago, Illinois, United States, 60611
      • Allakos Investigational Site
  • Indiana
    • Indianapolis, Indiana, United States, 46202
      • Allakos Investigational Site
  • Iowa
    • Iowa City, Iowa, United States, 52242
      • Allakos Investigational Site
  • Kentucky
    • Lexington, Kentucky, United States, 40503
      • Allakos Investigational Site
  • Louisiana
    • Crowley, Louisiana, United States, 70526
      • Allakos Investigational Site
  • Maryland
    • Chevy Chase, Maryland, United States, 20815
      • Allakos Investigational Site
  • Massachusetts
    • Boston, Massachusetts, United States, 02111
      • Allakos Investigational Site
    • Boston, Massachusetts, United States, 02115
      • Allakos Investigational Site
    • Boston, Massachusetts, United States, 02215
      • Allakos Investigational Site
  • Michigan
    • Ann Arbor, Michigan, United States, 48109
      • Allakos Investigational Site
    • Troy, Michigan, United States, 48098
      • Allakos Investigational Site
  • Missouri
    • Kansas City, Missouri, United States, 64108
      • Allakos Investigational Site
  • Montana
    • Kalispell, Montana, United States, 59901
      • Allakos Investigational Site
  • Nevada
    • Las Vegas, Nevada, United States, 89106
      • Allakos Investigational Site
    • Reno, Nevada, United States, 89511
      • Allakos Investigational Site
  • New York
    • Great Neck, New York, United States, 11021
      • Allakos Investigational Site
    • New York, New York, United States, 10029
      • Allakos Investigational Site
  • North Carolina
    • Asheville, North Carolina, United States, 28801
      • Allakos Investigational Site
    • Chapel Hill, North Carolina, United States, 27599
      • Allakos Investigational Site
    • Charlotte, North Carolina, United States, 28210
      • Allakos Investigational Site
    • Charlotte, North Carolina, United States, 28277
      • Allakos Investigational Site
    • Durham, North Carolina, United States, 27710
      • Allakos Investigational Site
    • High Point, North Carolina, United States, 27262
      • Allakos Investigational Site
    • Rocky Mount, North Carolina, United States, 27804
      • Allakos Investigational Site
  • Ohio
    • Akron, Ohio, United States, 44302
      • Allakos Investigational Site
    • Cincinnati, Ohio, United States, 45231
      • Allakos Investigational Site
    • Cincinnati, Ohio, United States, 45229
      • Allakos Investigational Site
    • Cleveland, Ohio, United States, 44106
      • Allakos Investigational Site
    • Dayton, Ohio, United States, 45415
      • Allakos Investigational Site
    • Mentor, Ohio, United States, 44060
      • Allakos Investigational Site
  • Oklahoma
    • Oklahoma City, Oklahoma, United States, 73112
      • Allakos Investigational Site
  • Pennsylvania
    • Danville, Pennsylvania, United States, 17822
      • Allakos Investigational Site
    • Philadelphia, Pennsylvania, United States, 19104
      • Allakos Investigational Site
  • South Carolina
    • Greenville, South Carolina, United States, 29615
      • Allakos Investigational Site
  • Tennessee
    • Chattanooga, Tennessee, United States, 37421
      • Allakos Investigational Site
    • Hixson, Tennessee, United States, 37343
      • Allakos Investigational Site
    • Nashville, Tennessee, United States, 37212
      • Allakos Investigational Site
  • Texas
    • Austin, Texas, United States, 78704
      • Allakos Investigational Site
    • Garland, Texas, United States, 75044
      • Allakos Investigational Site
    • San Antonio, Texas, United States, 78229
      • Allakos Investigational Site
  • Utah
    • Ogden, Utah, United States, 84405
      • Allakos Investigational Site
    • Riverton, Utah, United States, 84065
      • Allakos Investigational Site
    • Salt Lake City, Utah, United States, 84132
      • Allakos Investigational Site
    • Sandy, Utah, United States, 84092
      • Allakos Investigational Site
  • Virginia
    • Leesburg, Virginia, United States, 20176
      • Allakos Investigational Site
  • Washington
    • Seattle, Washington, United States, 98105
      • Allakos Investigational Site
    • Seattle, Washington, United States, 98115
      • Allakos Investigational Site

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 12 years to 80 years (Child, Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Key Inclusion Criteria:

1. Male or female aged ≥12 and ≤80 years at the time of signing ICF.
2. Confirmed diagnosis of EoE and esophageal intraepithelial eosinophilic infiltration of ≥15 eosinophils/hpf in 1 hpf from a biopsy collected during the Screening EGD without any other cause for the esophageal eosinophilia.
3. History (by patient report) of an average of ≥2 episodes of dysphagia with intake of solid foods per week during the 4 weeks prior to Screening.
4. Subjects must have failed or not be adequately controlled on standard of care treatments for EoE symptoms, which could include PPI, systemic or topical corticosteroids, and/or diet, among others.
5. If on an allowed treatment for EoE, stable dose for at least 4 weeks prior to Screening and willingness to continue that dose for the study duration.
6. If patient is on pre-existing dietary restrictions, willingness to maintain dietary restrictions throughout the study, as much as possible.
7. Able and willing to comply with all study procedures.
8. Female subjects must be either post-menopausal for at least 1 year with FSH level >30 mIU/mL at Screening or surgically sterile (tubal ligation,hysterectomy, or bilateral oophorectomy) for at least 3 months, or if of childbearing potential, have a negative pregnancy test and agree to use dual methods of contraception, or abstain from sexual activity from screening until the end of the study, or for 120 days following the last dose of study drug, whichever is longer. Male subjects with female partners of childbearing potential must agree to use a highly effective method of contraception from Screening until the end of the study or for 120 days following the last dose of study drug,whichever is longer. All fertile men with female partners of childbearing potential should be instructed to contact the Investigator immediately if they suspect their partner might be pregnant at any time during study participation.

Key Exclusion Criteria:

1. Concomitant EG, EoD, or eosinophilic colitis (EC).
2. EG and/or EoD (≥30 eosinophils/hpf in 5 hpf in the stomach and/or ≥30 eosinophils/hpf in 3 hpf in the duodenum) as determined by central histology assessment of biopsies collected during the Screening EGD.
3. Causes of esophageal eosinophilia other than EoE or one the following: hypereosinophilic syndrome, eosinophilic granulomatosis with polyangiitis, or peripheral blood absolute eosinophil count of >1500 eosinophils/μL.
4. History of inflammatory bowel disease, celiac disease, achalasia, and/or esophageal surgery.
5. Any esophageal stricture unable to be passed with a standard diagnostic 9 mm to 10 mm upper endoscope or any critical esophageal stricture that requires dilation during screening.
6. History of bleeding disorders or esophageal varices.
7. History of malignancy; except carcinoma in situ, early stage prostate cancer, or non-melanoma skin cancers. However, cancers that have been in remission for more than 5 years and are considered cured, can be enrolled (with the exception of breast cancer). All history of malignancy (including diagnosis, dates, and compliance with cancer screening recommendations) must be documented and certified by the Investigator, along with the statement that in their clinical judgment the tissue eosinophilia is attributable to EGID, rather than recurrence of malignancy.
8. Active Helicobacter pylori infection (as determined by central histology staining of the biopsy collected during the Screening EGD), unless treated and confirmed to be negative prior to randomization and symptoms remain consistent.
9. Positive Ova and Parasite (O&P) test at Screening, seropositive for Strongyloides stercoralis at Screening, and/or treatment for a clinically significant helminthic parasitic infection within 6 months of Screening.
10. Seropositive for HIV or hepatitis at Screening, except for vaccinated patients or patients with a history of hepatitis that has since resolved.
11. Prior exposure to AK002 or hypersensitivity to any constituent of AK002.
12. Change in dose of inhaled corticosteroids, nasal corticosteroids, PPI, and/or diet therapy within 4 weeks prior to Screening.
13. Use of oral corticosteroids (swallowed topical or systemic corticosteroids) within 8 weeks prior to Screening.
14. Use of any biologics or medications that may interfere with the study, such as immunosuppressive or immunomodulatory drugs including azathioprine, JAK inhibitors, 6-mercaptopurine, methotrexate, cyclosporine, tacrolimus, anti-TNF, anti-IL-4 receptor, e.g., dupilumab), anti-IL-5 (e.g., mepolizumab), anti-IL-5 receptor (e.g., benralizumab), anti-IL-13 (e.g., lebrikizumab), anti-IgE (e.g., omalizumab), within 12 weeks prior to Screening.
15. Participation in a concurrent interventional study with the last intervention occurring within 30 days prior to administration of study drug or 90 days or 5 half-lives, whichever is longer, for biologic products.
16. Vaccination with live attenuated vaccines ≤30 days prior to initiation of treatment in the study, during the treatment period, or vaccination expected ≤5 half-lives (≤4 months) following study drug administration.
17. Treatment with chemotherapy or radiotherapy in the preceding 6 months.
18. Presence of abnormal laboratory values considered by the Investigator to be clinically significant.
19. Any disease, condition (medical or surgical), or cardiac abnormality, which in the opinion of the Investigator, would place the subject at increased risk.
20. Known history of alcohol, drug, or other substance abuse or dependence.
21. Women who are pregnant, breastfeeding, or planning to become pregnant while participating in the study.
22. Any other reason that in the opinion of the Investigator or Medical Monitor makes the patient unsuitable for enrollment.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Placebo; Subjects in this arm will receive 6 monthly doses of placebo.	Other: Placebo; Placebo
Experimental: 1 mg/kg of lirentelimab (AK002); Subjects in this arm will receive 6 monthly doses of lirentelimab (AK002) (1mg/kg).	Drug: lirentelimab (AK002); Lirentelimab (AK002) is a humanized non-fucosylated immunoglobulin G1 (IgG1) monoclonal antibody directed against Siglec-8.
Experimental: 3 mg/kg of lirentelimab (AK002); Subjects in this arm will receive 6 monthly doses of lirentelimab (AK002): A first dose of 1 mg/kg, followed by 5 monthly doses of 3 mg/kg.	Drug: lirentelimab (AK002); Lirentelimab (AK002) is a humanized non-fucosylated immunoglobulin G1 (IgG1) monoclonal antibody directed against Siglec-8.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of Subjects Who Achieve a Peak Esophageal Intraepithelial Count of ≤6 Eosinophils/Hpf at Week 24	Esophageal intraepithelial eosinophil count obtained by esophageal endoscopy with biopsies.	At Week 24
Change in Dysphagia Symptom Questionnaire (DSQ) Score From Baseline to Weeks 23-24.	The DSQ is used to measure the frequency and intensity of dysphagia. DSQ scores can range from 0 to 84, with a lower score indicating less-frequent or less-severe dysphagia.	Baseline to Weeks 23-24

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percent Change in Peak Esophageal Intraepithelial Eosinophil Count From Baseline to Week 24	Esophageal intraepithelial eosinophil count obtained by esophageal endoscopy with biopsies. A greater esophageal intraepithelial eosinophil count from baseline indicates worsening disease.	Baseline to Week 24
Subjects Achieving Peak Esophageal Intraepithelial Eosinophil Count of ≤1 Eosinophil/Hpf at Week 24	Esophageal intraepithelial eosinophil count obtained by esophageal endoscopy with biopsies.	At Week 24
Subjects Achieving Peak Esophageal Intraepithelial Eosinophil Count of <15 Eosinophils/Hpf at Week 24	Esophageal intraepithelial eosinophil count obtained by esophageal endoscopy with biopsies.	At Week 24
Number of Treatment Responders	Treatment responders defined by >30% improvement in symptoms (DSQ) at Weeks 23-24 and peak intraepithelial eosinophilic count of ≤6 cells/hpf at Week 24	At Weeks 23-24 and Week 24, Respectively
Subjects Who Achieve >50% Reduction in DSQ Score From Baseline to Weeks 23-24	The DSQ is used to measure the frequency and intensity of dysphagia. DSQ scores can range from 0 to 84, with a lower score indicating less-frequent or less-severe dysphagia.	Weeks 23-24
Percent Change in DSQ Score From Baseline to Weeks 23-24	The DSQ is used to measure the frequency and intensity of dysphagia. DSQ scores can range from 0 to 84, with a lower score indicating less-frequent or less-severe dysphagia.	Baseline to Weeks 23-24
Change in Biweekly Mean DSQ Over Time Using MMRM	The DSQ is used to measure the frequency and intensity of dysphagia. DSQ scores can range from 0 to 84, with a lower score indicating less-frequent or less-severe dysphagia.	Baseline to Weeks 23-24
Change in EoE Reference Score for Endoscopic Abnormalities (EREFS) From Baseline to Week 24	EoE esophageal characteristics analyzed based on the EoE-EREFS, a scoring system for inflammatory and remodeling features of disease. The overall total score ranges from 0 to 18 with higher number indicating worse disease.	Baseline to Week 24

Collaborators and Investigators

• Sponsor: Allakos Inc.
• Investigators: Study Director: Craig Paterson, MD, Allakos Inc.

Study record dates

Study Major Dates

• Study Start (Actual): July 6, 2020
• Primary Completion (Actual): June 4, 2021
• Study Completion (Actual): January 18, 2022

Study Registration Dates

• First Submitted: March 24, 2020
• First Submitted That Met QC Criteria: March 24, 2020
• First Posted (Actual): March 26, 2020

Study Record Updates

• Last Update Posted (Estimated): January 1, 2024
• Last Update Submitted That Met QC Criteria: December 13, 2023
• Last Verified: December 1, 2023

More Information

Terms related to this study

• Keywords: Eosinophil; Esophagitis; EoE
• Additional Relevant MeSH Terms: Digestive System Diseases; Immune System Diseases; Hypersensitivity, Immediate; Hematologic Diseases; Gastrointestinal Diseases; Gastroenteritis; Hypersensitivity; Esophageal Diseases; Leukocyte Disorders; Eosinophilia; Eosinophilic Esophagitis; Esophagitis
• Other Study ID Numbers: AK002-014

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No