A Study to Evaluate the Safety, Tolerability, and Clinical Benefit of AK002 in Adult Patients with Mast Cell Gastritis and/or Gastroenteritis


About this study

The purpose of this study is to evaluate the safety and tolerability of AK002 in patients with mast cell gastritis and/or gastroenteritis, examine changes in number of mast cells/HPF in gastric and duodenal biopsies, examine any change in gastrointestinal symptom score as estimated by a daily patient-reported outcome (PRO) questionnaire and look for any changes in absolute peripheral blood eosinophil counts.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria:

  • Male or female aged ≥18 and ≤80 years at the time of signing ICF.
  • Failed the screening process for Study AK002-003 due to not meeting the eligibility criterion of eosinophilia of the gastric mucosa (defined as ≥30 eosinophils/HPF in 5 HPFs) or duodenal mucosa (≥30 eosinophils/HPF in 3 HPFs) from the EGD performed during the AK002-003 screening period.
  • Average weekly score of ≥3 (on a scale from 0–10) recorded for abdominal pain, diarrhea, or nausea on the PRO questionnaire during at least 2 out of 3 weeks of PRO collection. A minimum of 4 questionnaires must be completed each qualifying week.
  • Have ≥30 mast cells/HPF in at least 3 HPFs in the duodenal and/or gastric mucosa from the EGD performed during the AK002-003 screening period.
  • Subjects must have failed or not be adequately controlled on standard of care treatments for EG or EGE symptoms (which could include PPIs, systemic or topical corticosteroids, and/or diet, among others).
  • If on other treatments for EG, EGE, or EoE at enrollment, stable dose for at least 5 half-lives prior to screening and willingness to continue on that dose for the duration of the study.
  • If patient is on pre-existing dietary restrictions, willingness to maintain dietary restrictions throughout the study, as much as possible.
  • Able and willing to comply with all study procedures.
  • Female subjects must be either post-menopausal for at least 1 year with FSH level >40 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 participati

Exclusion Criteria:

  • Known hypersensitivity to any constituent of the study drug.
  • Diagnosis of celiac disease or H. pylori infection as determined by screening EGD or a history of celiac disease diagnosed by prior EGD.
  • Presence of abnormal laboratory values considered by the Investigator to be clinically significant.
  • Grade 2 or higher lymphopenia (<0.8 × 109/L lymphocytes).
  • Any disease, condition (medical or surgical), or cardiac abnormality, which, in the opinion of the Investigator, would place the subject at increased risk.
  • History of malignancy; except carcinoma in situ in the cervix, 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 as cured by the Investigator.
  • Treatment with chemotherapy or radiotherapy in the preceding 6 months.
  • Treatment for a clinically significant helminthic parasitic infection within 6 months of screening and/or a positive helminthic test at screening.
  • Use of any medications that may interfere with the study such as immunosuppressive or immuno-modulatory drugs (including azathioprine, 6-mercaptopurine, methotrexate, cyclosporine, tacrolimus, anti-TNF, anti-IL-5, anti-IL-5 receptor, dupilumab, anti-IgE antibodies, omalizumab) or systemic corticosteroids with a daily dose >10 mg of prednisone or equivalent, during 5 half-lives prior to screening or during the screening period, except for omalizumab taken in asthma and/or urticaria patients, where their asthma and/or urticaria cannot be controlled on other medications. In such cases, the dose of omalizumab should remain stable during screening and throughout the study.
  • Vaccination with live attenuated vaccines within 30 days prior to initiation of treatment in the study, during the treatment period, or vaccination expected within 5 half-lives of the study drug administration.
  • Known history of alcohol, drug, or other substance abuse or dependence.

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status

Rochester, Minn.

Mayo Clinic principal investigator

Joseph Murray, M.D.

Closed for enrollment

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