Eligibility Details:  
        Inclusion Criteria:
          1. Male and female patients 18 through 65 years of age.
          2. Women of childbearing potential (WOCBP) must not be actively seeking pregnancy, and
             must use an effective form of birth control (confirmed by the Investigator). Effective
             forms of birth control include: true sexual abstinence, a vasectomized sexual partner,
             Implanon, female sterilization by tubal occlusion, any effective intrauterine device
             (IUD)/ levonorgestrel Intrauterine system (IUS), Depo-Proveraâ„¢ injections, oral
             contraceptive, and Evra Patchâ„¢ or Nuvaringâ„¢. WOCBP must agree to use effective method
             of birth control, as defined above, from enrolment, throughout the study duration and
             within 16 weeks after last dose of IP. They must demonstrate a negative serum
             pregnancy test at screening and demonstrate a negative urine pregnancy test
             immediately before each dose of study drug or placebo. Women not of childbearing
             potential are defined as women who are either permanently sterilized (hysterectomy,
             bilateral oophorectomy, or bilateral salpingectomy), or who are postmenopausal. Women
             will be considered postmenopausal if they have been amenorrheic for 12 months prior to
             the planned date of randomization without an alternative medical cause. The following
             age-specific requirements apply:
               -  Women <50 years old would be considered postmenopausal if they have been
                  amenorrheic for 12 months or more following cessation of exogenous hormonal
                  treatment and follicle stimulating hormone (FSH) levels in the postmenopausal
                  range.
               -  Women ≥50 years old would be considered postmenopausal if they have been
                  amenorrheic for 12 months or more following cessation of all exogenous hormonal
                  treatment.
          3. All male patients who are sexually active must agree to use an acceptable method of
             contraception (condom with or without spermicide, vasectomy) from the first dose of
             investigational product (IP) until 16 weeks after their last dose.
          4. General good health
          5. Moderate to severe atopic dermatitis
          6. Able to understand and give written informed consent and has signed a written informed
             consent form approved by the investigator's Research Ethics Board (REB)
        The following inclusion criteria must be met for entry into the dosing phase of the study:
          1. Positive skin-prick test to common aeroallergens (including cat, dust mite, grass,
             pollen)
          2. Positive late cutaneous response to intradermal allergen challenge
        Exclusion Criteria:
          1. History of anaphylaxis to any biologic therapy or vaccine
          2. History of clinically significant hypotensive episodes or symptoms of fainting,
             dizziness, or light headedness, as judged by the investigator
          3. Any history or symptoms of cardiovascular disease, particularly coronary artery
             disease, arrhythmias, hypertension, or congestive heart failure
          4. Any history or symptoms of significant neurologic disease, including transient
             ischemic attack (TIA), stroke, seizure disorder, or behavioral disturbances
          5. Any history or symptoms of clinically significant autoimmune disease
          6. Any history of clinically significant haematologic abnormality, including coagulopathy
             or any history of chronic treatment with anticoagulants (e.g. warfarin, etc) or
             antiplatelet agent (e.g, aspirin, etc)
          7. Clinically significant abnormalities in laboratory test results at enrolment and
             during the screening period (including complete blood count, coagulation, chemistry
             panel and urinalysis) unless judged not significant by the investigator.
          8. Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) level ≥2.5 times
             the upper limit of normal (ULN) confirmed during screening period
          9. Being pregnant or lactating or have positive serum pregnancy test at enrolment or
             positive urine pregnancy test during the study
         10. Concomitant disease or condition which could interfere with the conduct of the study,
             or for which the treatment might interfere with the conduct of the study, or which
             would, in the opinion of the investigator, pose an unacceptable risk to the patient in
             this study, including, but not limited to, cancer, alcoholism, drug dependency or
             abuse, or psychiatric disease
         11. Severe concomitant illness(es) that, in the investigator's judgment, would adversely
             affect the patient's participation in the study
         12. Presence of skin comorbidities that may interfere with study assessments
         13. History of cancer: Patients who have had basal cell carcinoma, localized squamous cell
             carcinoma of the skin, or in situ carcinoma of the cervix are eligible provided that
             the subject is in remission and curative therapy was completed at least 12 months
             prior to the date informed consent. Patients who have had other malignancies are
             eligible provided that the subject is in remission and curative therapy was completed
             at least 5 years prior to the date of informed consent.
         14. Patient who has a scheduled in-patient surgery or hospitalization during the study.
         15. History of Guillain-Barré syndrome
         16. A helminth parasitic infection diagnosed within 24 weeks prior to the date informed
             consent is obtained that has not been treated with, or has failed to respond to
             standard of care therapy
         17. Positive hepatitis B surface antigen, or hepatitis C virus antibody serology, or a
             positive medical history for hepatitis B or C. Patients with a history of hepatitis B
             vaccination without history of hepatitis B are allowed to enrol
         18. A history of known immunodeficiency disorder including a positive human
             immunodeficiency virus (HIV) test
         19. Receipt of immunoglobulin or blood products within 30 days prior to the date informed
             consent is obtained
         20. Receipt of any marketed (eg omalizumab) or investigational biologic within 4 months or
             5 half-lives prior to randomization is obtained, whichever is longer
         21. Treatment with an investigational drug within 8 weeks or within 5 half-lives (if
             known), whichever is longer, before the baseline visit
         22. Any allergen immunotherapy within 4 months prior to or throughout the study.
         23. Having used any of the following treatments within 4 weeks before the Day -2 baseline
             visit, or any condition that, in the opinion of the investigator, is likely to require
             such treatment(s) during study:
               1. Immunosuppressive/immunomodulating drugs (eg, systemic corticosteroids,
                  cyclosporine, mycophenolate-mofetil, interferon gamma (IFN-γ), Janus kinase
                  inhibitors, azathioprine, methotrexate, etc.)
               2. Phototherapy for AD
         24. Any cell-depleting agents including but not limited to rituximab: within 6 months
             before the baseline visit, or until lymphocyte count returns to normal, whichever is
             longer
         25. Initiation of treatment of AD with prescription moisturizers or moisturizers
             containing additives such as ceramide, hyaluronic acid, urea, or filaggrin degradation
             products during the screening period (patients may continue using stable doses of such
             moisturizers if initiated before the screening visit)
         26. Regular use (more than 2 visits per week) of a tanning booth/parlor within 4 weeks of
             the baseline visit
         27. Active chronic or acute infection requiring treatment with systemic antibiotics,
             antivirals, antiparasitics, antiprotozoals, or antifungals within 2 weeks before the
             baseline visit, or superficial skin infections within 1 week before the baseline
             visit. Note: patients may be re-screened after infection resolves
         28. Known or suspected history of immunosuppression, including history of invasive
             opportunistic infections (eg, histoplasmosis, listeriosis, coccidioidomycosis,
             pneumocystosis, aspergillosis) despite infection resolution: or unusually frequent,
             recurrent, or prolonged infections, per investigator judgment
         29. Planned or anticipated major surgical procedure during the patient's participation in
             this study
         30. Receipt of live attenuated vaccines 30 days prior to the date of randomization.
             Receipt of inactive/killed vaccinations (eg, inactive influenza) are allowed provided
             they are not administered within 1 week before/after any IP administration.
         31. Patient is a member of the investigational team or his/her immediate family
         32. Pregnant woman
         33. Previously received benralizumab (MEDI-563)