Regeneron AA Multicenter (Dupilumab)

INCLUSION CRITERIA:

• Male or female subjects who are at least 18 years old at the time of informedconsent.

• Subject is able to understand and voluntarily sign an informed consent documentprior to participation in any study assessments or procedures.

• Subject is able to adhere to the study visit schedule and other protocolrequirements.

• Females of childbearing potential (FCBP) must have a negative pregnancy test atScreening and Baseline. While on investigational product and for at least 28 daysafter taking the last dose of investigational product (IP), FCBP who engage inactivity in which conception is possible must use one of the approved contraceptiveoptions described below:

• Option 1: Any one of the following highly effective methods: hormonalcontraception (oral, injection, implant, transdermal patch, vaginal ring);intrauterine device (IUD); tubal ligation; or partner's vasectomy, OR;

• Option 2: Male or female condom (latex condom or non-latex condom NOT made outof natural [animal] membrane [for example, polyurethane]); PLUS one additionalbarrier method: (a) diaphragm with spermicide; (b) cervical cap withspermicide; or (c) contraceptive sponge with spermicide.

• If subject is a female of non-childbearing potential, she must have documentedhistory of infertility, be in a menopausal state for one year, or had ahysterectomy, bilateral tubal ligation, or bilateral oophorectomy.

• Subject has a history of at least 6 months of moderate to severe AA (≥ 50% scalpinvolvement) as measured using the SALT score; OR subject has ≥ 95% loss of scalphair for enrollment as AA totalis (AT) or universalis (AU) subtypes.

• Subject has a screening IgE > 200 and/or personal and/or familial history of atopy.

• Subjects must meet the following laboratory criteria:

• White blood cell count ≥ 3000/mm3 (≥ 3.0 x 109/L) and < 14,000/mm3 (≤ 14 x 109/L).

• Platelet count ≥ 100,000/μL (≥ 100 x 109/L).

• Serum creatinine ≤ 1.5 mg/dL (≤ 132.6 μmol/L).

• AST (SGOT) and ALT (SGPT) ≤ 2 x upper limit of normal (ULN). If the initialtest shows ALT or AST > 2 times the ULN, one repeat test is allowed during theScreening Phase.

• Total bilirubin ≤ 2 mg/dL (34 μmol/L). If the initial test shows totalbilirubin > 2 mg/dL (34 μmol/L), one repeat test is allowed during theScreening Phase.

• Hemoglobin ≥ 10 g/dL (≥ 6.2 mmol/L).

• Subject is judged to be in otherwise good overall health following a detailedmedical and medication history, physical examination, and laboratory testing.

EXCLUSION CRITERIA:

The presence of any of the following will exclude a subject from enrollment:

• Subject is pregnant or breastfeeding.

• Subject's cause of hair loss is indeterminable and/or they have concomitant causesof alopecia, such traction, cicatricial, pregnancy-related, drug-induced, telogeneffluvium, or advanced androgenetic alopecia (i.e. Ludwig Type III orNorwood-Hamilton Stage ≥ V).

• Subject has a history of AA with no evidence of hair regrowth for ≥ 7 years sincetheir last episode of hair loss.

• Severe, uncontrolled asthma or a history of life-threatening asthma exacerbationswhile on appropriate anti-asthmatic mediations.

• Subject has an active bacterial, viral, or helminth parasitic infections; OR ahistory of ongoing, recurrent severe infections requiring systemic antibiotics

• Subject with a known or suspected underlying immunodeficiency or immune-compromisedstate as determined by the investigator.

• Subject has a concurrent or recent history of severe, progressive, or uncontrolledrenal, hepatic, hematological, intestinal, metabolic, endocrine, pulmonary,cardiovascular, or neurological disease.

• Active hepatitis B, hepatitis C, human immunodeficiency virus (HIV), or positive HIVserology or active or untreated latent tuberculosis at the time of screening forsubjects determined by the investigators to be at high-risk for this disease.

• Subject has a suspected or active lymphoproliferative disorder or malignancy; OR ahistory of malignancy within 5 years before the Baseline assessment, except forcompletely treated in situ non-melanoma skin and cervical cancers without evidenceof metastasis.

• Subject has received a live attenuated vaccine ≤ 30 days prior to studyrandomization.

• Subject has any uncertain or clinically significant laboratory abnormalities thatmay affect interpretation of study data or endpoints.

• Subject has any other medical or psychological condition that, in the opinion of theinvestigator, may present additional unreasonable risks as a result of theirparticipation in the study and/or interfere with clinic visits and necessary studyassessments.

• History of adverse systemic or allergic reactions to any component of the studydrug.

• Severe, untreated asthma or a history of life-threatening asthma exacerbations whileon appropriate anti-asthmatic mediations.

• Use of systemic immunosuppressive medications, including, but not limited to,cyclosporine, systemic or intralesional corticosteroids, mycophenolate mofetil,azathioprine, methotrexate, tacrolimus, or ultraviolet (UV) phototherapywith/without Psoralen Ultraviolet A (PUVA) therapy within 4 weeks prior torandomization.

• Use of an oral JAK inhibitor (tofacitinib, ruxolitinib, baricitinib, orinvestigational oral JAK Inhibitors) within 12 weeks prior to the Baseline visit.

• Subject has been previously treated with dupiliumab.

• Subject has used topical corticosteroids, and/or tacrolimus, and/or pimecrolimuswithin 1 week before the Baseline visit.

• Subject currently uses or plans to use anti-retroviral therapy at any time duringthe study.