A Study of Enfortumab Vedotin in People With Adenoid Cystic Carcinoma

Inclusion Criteria: * Patients must have pathologically or cytologically confirmed adenoid cystic carcinoma. Cancers arising from non-salivary gland primary sites are allowed. * Patients must have recurrent and/or metastatic disease not amenable to other curative intent therapy. * At least 4 weeks must have elapsed since the end of prior systemic treatment and/or 2 weeks since completion of radiotherapy with resolution of all treatment related toxicity to NCI CTCAE Version 5.0 grade \<1 (or tolerable grade 2) or back to baseline (except for alopecia, lymphopenia, or hypothyroidism) prior to starting study drug treatment. * Patients must have RECIST V1.1 measurable disease, defined as at least one nonnodal lesion measuring ≥ 20 mm with conventional techniques or as ≥10mm with CT scan, MRI, or calipers by clinical exam in the longest dimension AND/OR a nodal lesion measuring ≥ 15 mm in the shortest dimension. Tumors in previously irradiated fields may be considered measurable if there is evidence of tumor progression after radiation treatment. * Patients must have documentation of a new or progressive lesion on radiologic imaging study performed within 6 months prior to study enrollment (progression of disease over any interval is allowed) and/or new/worsening disease related symptoms within 6 months prior to study enrollment. Note: This assessment will be performed by the treating investigator and evidence of progression by RECIST criteria is not required. * Age ≥ 18 years of…