POC Study to Evaluate BSI-045B in Moderate-to-severe Atopic Dermatitis

Main inclusion Criteria:

• In the opinion of the Investigator, the patient is capable of understanding andcomplying with protocol requirements.

• The patient signs and dates a written ICF prior to the initiation of any studyprocedures.

• The patient has a diagnosis of AD (according to the criteria established by Hanifinand Rajka, 1980). The diagnosis of AD must have been present for at least 1 year,and the patient's AD must have been active for at least 3 months.

• The patient is aged 18 to 65 years, inclusive at the time of consent. Patients ofany gender are eligible.

• The EASI is ≥12 at Screening and on Day 1.

• The score on the IGA is ≥3 (scale of 0 to 4) at Screening and on Day 1.

• The total body surface area (BSA) affected by AD is ≥10% as assessed by the physicalexamination at Screening and on Day -1.

• The patient has not received prior treatment with topical or systemic medications ORthe patient has active disease despite topical or systemic treatment as per theInvestigator at the time of screening.

• A male patient who is non-sterilized and sexually active with a female partner ofchildbearing potential, and female patient of childbearing potential who is sexuallyactive with a non-sterilized male partner agrees to use highly effectivecontraception from the time of signing the ICF throughout the duration of the studyand for 90 days (~5 half lives) after the last dose of study drug.

Main Exclusion Criteria:

• The patient has another dermatologic condition that might confound a diagnosis of ADor a treatment assessment.

• The patient has any clinically significant illness that may affect the safety,increase the risk for seizure or lower the seizure threshold, or potentiallyconfound the study results.

• The patient has abnormal laboratory values during the Screening Period: ALT and/orAST > 1.5 ULN, total bilirubin ≥ 1.5 mg/dL, estimated glomerular filtration rate (GFR) < 60 mL/min (based on Cockcroft-Gault calculation), hemoglobin≤ 10 g/dL,platelet count ≤ 150 ×103/µL, creatine kinase > 2.5×ULN.

• The patient has a history of anaphylaxis following biologic therapy.

• The patient has a history of allergy to corticosteroids, diphenhydramine,hydroxyzine, cetirizine, or fexofenadine.

• The patient has a history of a clinically significant infection within 4 weeks priorto Screening.

• The patient has been diagnosed with a helminthic parasitic infection within 6 monthsprior to Screening.

• The patient has a history of drug abuse (defined as any illicit drug use) or ahistory of alcohol abuse within 1 year prior to Screening or is unwilling to agreeto abstain from alcohol and drugs (including cannabinoids) throughout the study.

• The patient had a major surgical or major dental procedure within 8 weeks prior toScreening.

• The patient is pregnant or lactating or intends to become pregnant or donate ovabefore, during, or within 90 days (~ 5 half-lives) since the last dose of studydrug.

• If male, the patient intends to donate sperm during this study or within 90 days (~ 5 half-lives) since the last dose of study drug.

• The patient has a history of neurologic abnormalities including abnormalelectroencephalography, brain injury including traumatic injury, perinatalcerebropathy, postnatal brain damage, blood-brain barrier abnormality, and cavernousangioma.

• The patient has a history of cerebral arteriosclerosis.

• The patient has a history of cancer. Patients with localized basal cell carcinoma,localized squamous cell carcinoma of the skin, or carcinoma in situ of the cervixmay be included in the study if they have completed curative treatment at least 12months prior to Screening. Patients with other malignant tumors may be included ifthey have completed curative treatment at least 5 years prior to the first dose ofstudy drug.

• The patient has a positive test result for hepatitis B surface antigen (HbsAg),antihepatitis C virus (HCV), a history of active tuberculosis, a positive testresult for human immunodeficiency virus (HIV), or a known history of HIV infectionat Screening.

• The patient has poor peripheral venous access.

• The patient has donated or lost ≥ 450 mL of blood (including plasmapheresis) or hada transfusion of any blood product within 90 days prior to the first dose of studydrug.

• The patient has an abnormal ECG at Screening or on Day -1. In the case of acorrected QT interval (Fridericia) (QTcF) > 450 ms or > 470 ms (patients with bundlebranch block) or PR interval outside the range of 115 to 220 ms, assessment may berepeated once for eligibility determination at Screening and/or on Day -1.

• The patient has a supine systolic blood pressure < 90 or > 144 mm Hg or a supinediastolic blood pressure < 50 or > 94 mm Hg at Screening or on Day -1. If out ofrange, assessment may be repeated once for eligibility determination at Screeningand/or on Day -1.

• The patient has a resting heart rate < 40 or > 90 bpm (not on ECGs) and consideredclinically significant by the Investigator at Screening or on Day 1. If out ofrange, the assessment may be repeated once for eligibility determination atScreening and/or on Day -1.

• The patient plans to use any other prohibited medication or undergo any prohibitedprocedure during the study. Oral antibiotics are permitted. Bleach baths are notpermitted.

• The patient has a risk of suicide on the Patient Health Questionnaire-2 (PH 2) or inthe judgment of the Investigator, or the patient has made a suicide attempt or has ahistory of deliberate self-harm in the 6 months prior to Screening.

• The patient is compulsorily detained for a medical or psychiatric illness.

• The patient or their immediate family are personnel at the clinical site.

• The patient is unable to comply with restrictions and prohibitedactivities/treatments as listed in the study protocol.