Inclusion Criteria:  Provided written informed consent. Male or female aged ≥18 and ≤80 years at the time of signing the informed consent form. Chronic AD (according to the American Academy of Dermatology Consensus Criteria) (Eichenfield, 2014) that has been present for at least 3 years before the screening visit. Documented recent history of inadequate response to treatment with topical medications such as topical corticosteroids, calcineurin inhibitors, or crisaborole for at least 4 weeks in the 6 months prior to screening, or subjects for whom these topical treatments are otherwise medically inadvisable (e.g., because of side effects or safety risks). EASI score of ≥16 at screening and at baseline. Involvement of at least 10% or more of BSA at screening and at baseline. An IGA score of 3 or above on a scale from 0-4 at screening and at baseline. The subject should have applied a stable dose of non-medicated, non-prescription, topical emollient at least twice daily for 7 consecutive days immediately before the baseline visit. Willing to apply a stable dose of non-medicated, non-prescription, topical emollient, as recommended by the Investigator at least twice daily, if not already on an emollient at the time of screening. Commitment to remain on the same dose(s) of AD medication(s), including topical emollients for the entire duration of study participation unless dose modification is due to unforeseen medical necessity. Willing and able to comply with the study procedures and visit schedule including follow-up visits. Negative screening ova and parasite test. Female subjects must be either postmenopausal 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 (e.g., missed or late menstrual period) at any time during study participation.  Exclusion Criteria:  Known hypersensitivity to any constituent of the study drug. Current use of biologics for any indication. Any exposure to dupilumab for any condition during the subject's lifetime. Anticipated use of topical or oral corticosteroids, calcineurin inhibitors, or crisaborole starting at the screening visit and during the entire course of the study. Treatment with any immunosuppressive or immunomodulatory drugs that may interfere with the study interpretation within 12 weeks prior to the screening visit. Treatment with chemotherapy or radiotherapy in the preceding 6 months. Presence of skin comorbidities/concomitant conditions that may interfere with study assessments or interpretation of study results. Any disease or condition (medical or surgical) that 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. Any disease, condition (medical or surgical), or cardiac abnormality that in the opinion of the Investigator would place the subject at increased risk. A helminth parasitic infection diagnosed within 6 months prior to the date informed consent is obtained that has not been treated with or has failed to respond to standard-of-care therapy. Evidence of active hepatitis B or C at screening based on serology. Evidence of active HIV infection at screening based on serology. Women who are pregnant, breastfeeding, or planning to become pregnant while participating in the study. Presence of an abnormal screening laboratory value considered to be clinically significant by the Investigator. Known or suspected history of alcohol, drug, or other substance abuse or dependence that, in the opinion of the Investigator, may interfere with study participation or assessments. Prior exposure to lirentelimab or known hypersensitivity to any constituent of the study drug. Participation in a concurrent interventional study with the last intervention occurring within 30 days prior to study drug administration (or 90 days or 5 half-lives, whichever is longer, for biologic products). Any other reason that in the opinion of the Investigator or the Medical Monitor makes the subject unsuitable for enrollment. 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 (4 months) of study drug administration.  This exclusion criterion does not apply to all types and formulations of vaccines (including live attenuated vaccines) currently authorized by FDA or other regulatory authority for the prevention of COVID-19, which may be administered before, during, or after the study.  The vaccine should not be administered within 7 days before and within 7 days after the administration of lirentelimab so that any side effects caused by either of the 2 medications can be more easily determined.